CONSERVATION BIOLOGY

The Science of Conservation Planning
Reed Noss

Basic Modeling Approaches to Species Viability
Michael Gilpin

Applying the Science of Conservation Planning to the
Biological Element of the Sonoran Desert Conservation Plan
Bill Shaw

 

INTRODUCTORY REMARKS

If you would all take your seats we will get started and have the close of the session at approximately 12:00 o'clock. Again, I would like to welcome everyone to this session. This session is on Conservation Biology. I'm Chuck Huckelberry, County Administrator and I welcome you on behalf of Pima County. We think today's session will be extremely interesting and what I'd like to do is introduce the Chair of the Board of Supervisors. Sharon.

 

SHARON BRONSON

I want to welcome you all, I'm Sharon Bronson and as Chuck indicated, I am Chair of the Pima County Board of Supervisors and I want to welcome you all once again to this fourth session of the steering committee. I think you are going to find this session one of the most exciting. We have some terrific speakers, very, very knowledgeable -- just tops in their fields and one of those presenters today is someone I am going to introduce now, someone who probably does not know it but he is somewhat responsible for my being up on the eleventh floor of the County Administration Building and he is Dr. William Shaw. I first got involved in environmental politics, if you will, because of that map that Dr. Shaw put together. How many years ago?

Dr. Shaw:Fifteen.

Fifteen years ago of critical sensitive habitat here in Pima County. Dr. Shaw is Professor and Chair of Wildlife and Fisheries Science in the School of Renewable Natural Resources at the U of A. He has been there since 1974, he has a degree from UC Berkeley and Utah State as well as the University of Michigan in Natural Resources. As I said, he has combined biology with urbanization, with things that deal with both people and animals not only in Pima County but throughout the world and he has just finished hosting, I think in May of this year, was that the first wildlife symposium on urban wildlife?

Dr. Shaw:Fourth.

Fourth wildlife symposium here in Tucson, Arizona and that was a very, very interesting symposium so without further ado, let me introduce to you Dr. Shaw who will tell you a little about what's going to go on today and introduce our presenters. Dr. Shaw.

 

DR. BILL SHAW:

Thank you Sharon, it is a real pleasure to be here today and see so many people interested in wildlife conservation in Tucson in the surrounding areas. As you know, the Sonoran Desert Conservation Plan includes a number of working groups, one of which is the Science and Technical Advisory Team which I have the honor of chairing and it includes representatives from Science and Natural Resource agencies throughout the Tucson area. As a group, we felt it was very important early on in this process to ensure that we have the best outside expertise that we could concerning the process of developing Comprehensive and a Multi-Species Habitat Conservation Plan for this community.

With the help of the County, we have been probably far more successful than we ever imagined we could be in that regard and I am really pleased today to introduce two speakers that are by any definition preeminent in the field of Conservation Biology. If you were to ask anyone to list a handful of names that have been prominent in efforts to integrate conservation into human activities from a scientific perspective, these two individuals would invariably come up so our first speaker is Reed Noss.

Reed is the President and Chief Scientist for Conservation Science Incorporated, he is also the Science Editor for a new magazine that is attempting to integrate Conservation Biology and Science Advocacy called Wild Earth. He is the President of the Society for Conservation Biology, he has a long history of involvement in Conservation Biology issues and I know on his bio here he also has some skills that could be quite handy in this field as well. He has a black belt in karate which was another reason we wanted him here for today's meeting. I could go on and on, he is the recipient of a Pew Fellowship in the Edward LaRoe Memorial Award which is the highest award of the Society for Conservation Biology gives. I won't go any farther than that because I think we are all more interested in hearing what he has to say. Reed.

 

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THE SCIENCE OF CONSERVATION PLANNING: REED NOSS

It's great to be back in Tucson. I was here just last spring for a symposium and I thought it was a great meeting. Like most biologists, I am going to show slides so we will get into that here in just a moment. Bill mentioned my martial arts experience. There is actually a lot of similarity between martial arts and Conservation Biology. You have to learn to roll with the punches over the years. They are both somewhat combative disciplines in some ways. I am going to talk a little bit today about the history of Conservation Planning. Julia Fonseca, who invited me, suggested in particular that I kind of lead you through how we got to where we are today with these regional scale, ecosystem level Habitat Conservation Plans and other similar types of projects. So if I could have the slides, we will get right into that. I guess I have the changer here....okay. Now these are either left slides or right slides. (Right slides). Okay.

Conservation as we know it on this continent began with not the protection of the ecosystems but with the protection of particular favored species from over-harvest. So for example, the first law that we know of on this continent for wildlife management was an ordinance passed in 1639 in the Colony of Rhode Island establishing a closed season on white-tailed deer. Other colonies followed suit over the next few decades. These first laws had to do with protecting particular favored species from over-harvest.

It was recognized without some kind of regulation, these species might be driven to extinction and, in fact, many colonies in the states did lose their deer populations, wild turkey and other game species for awhile.

Now it is ironic that a lot of these early measures to protect certain species were accompanied soon thereafter by measures to eradicate other species. For example, Massachusetts late in the 1600's established a closed season on deer and at the same time established a bounty on wolves. So we had some definite favoritism shown right from the beginning about which species were kind of important.

Now the effort to protect land in North America came somewhat later. This is fairly obvious why we concentrated first on species--- because land seemed inexhaustible. Here we were in a continent that was fairly lightly populated by Native Americans, maybe at the most ten million people on the continent at the time Europeans first arrived, and their impacts were relatively benign. So we had what a lot of people saw as wilderness, although we do know that in some regions the Native Americans had tremendous influence on the landscape.

In other regions it was probably very, very minor. But when we first started setting aside land--- which we did in a big way when we established Yellowstone National Park in 1872--- biology and other scientific considerations really did not enter into it. We were interested in protecting for all time, the wonders of nature. The Yellowstone National Park Act of 1872 ushered in an era that historian Alfred Runts has called monumentalism. We wanted to protect these monuments, these scenic wonders.

I am glad we did. But obviously, from a biological standpoint, we found that they were not enough. When then did science first become involved in conservation planning? This is really the theme of today's session--- biological science and its contribution to conservation. Well there were some scientists involved in some of the early national park designations, but I think that science became involved in a big way in 1917 when the Ecological Society of America was founded. One of the first actions of this professional society of ecologists was to establish a Committee for the Preservation of Natural Conditions. They established this committee in response to a request from the National Research Council to compile a list and map of all the preserved and preservable areas on the continent that still remained in relatively natural condition, so that was in 1917.

This committee was chaired by a prominent ecologist, Victor Shelford, and operated for nearly 30 years. It had probably a relatively minor influence at the time on what lands were acquired for national parks, wilderness and other areas, but in the long run, its impact turned out to be quite substantial. This group of ecologists then was concerned with representation of all of our major ecosystem types in North America in some kind of system of protected areas.

That was their main theme and they were not just thinking about little postage stamps or pieces that you stick on a shelf and look at later on. They were interested in maintaining entire ecosystems. This was really an ambitious kind of effort at the time. They emphasized, for example, large carnivores and the role that they play in ecosystems and sought to maintain areas large enough that could support populations of these species over the long term. So again, this was a very forward thinking group for back in the teens and the 1920's here on this continent.

The great conservationist, Aldo Leopold, was also a member of these committees. As I mentioned, this committee of Victor Shelford's operated for about 30 years until 1946, when the Board of the Ecological Society of America determined that this kind of applied conservation work was a little bit too radical. It was too much advocacy. They voted to disband Shelford's Committee. Undeterred, Shelford immediately established a separate organization which he called the Ecologist's Union, which in 1950 was renamed the Nature Conservancy. Today, the Nature Conservancy is, of course, the major land protection organization working on this continent.

The Nature Conservancy, though, shifted quite a bit from this early emphasis of Shelford's Committee on large areas and complete ecosystems. They turned to a more practical way to protect things. During the 1970's in particular, while Bob Jenkins at that time was Vice President of the Nature Conservancy for Science, the Conservancy established the Natural Heritage Programs. Most states now have active Natural Heritage Programs incorporated into their state agencies. As many of you know, these programs keep track of what are called the elements of diversity, which are primarily rare species, rare plant communities, and where they are distributed across the landscape. Again, for practical reasons though, they tended to focus on relatively small areas and on rare plants because it is easier to track these occurrences of rare plants than, say, grizzly bears across the area of a state.

The modern science of Conservation Biology as we know it developed during the 1970's largely in response to the increasing awareness of an extinction crisis; that we are losing species at a faster rate than would go extinct naturally. Now, biologists had ve been aware of course that of human-caused extinctions for some time. Consider the last Passenger Pigeon, which was once the most abundant bird it is thought in the entire world, billions of these birds. The last Passenger Pigeon died in 1914 in the Cincinnati Zoo. Still at that time, extinction was not a major concern of most scientists or conservationists.

It was not until the 1960's that scientists and some conservationists began to become aware that the rate of extinctions was really increasing pretty dramatically over time. This graph is from an article in the 1960's by a German author, showing the increase in the extinctions of birds and mammals, (the mammals in white bars, birds in blue bars) in relation to the human population from 1615 to 1950. This provided a pretty compelling argument, and there were other demonstrations of this that the increasing impact of humans on the earth was having an effect that most of us would not consider desirable.

It was this kind of awareness that is responsible for the emergence of Conservation Biology as we know it. Early Conservation Biology, in say the 1970's and 1980's, was concerned largely with incorporating lessons from Island biogeographic theory into conservation planning. Island biogeographic theory begins with the an observation that goes way back-- that bigger areas have more species. This is known as the species- area relationship, and is one of the best documented laws of nature in biology.

We know that as the area increases, the number of species increases. There is probably a number of factors that contribute to this, we know there is a number of factors. Probably the biggest one is that larger areas have more habitats, and with more habitats, you have more species. The first person, (at least in writing) to acknowledge this species/area relationship was Johann Forrester, who was Captain Cook's naturalist on Cook's second voyage around the world. In the 1790's he wrote that, "As the perimeter of an island increases, so does its number of species," and this has been formalized in these kinds of relationships.

Well, Island biogeographic theory provided a general explanation for the species/area relationship. It suggested that the number of species on any island or island-like habitat, for example, any isolated piece of habitat whether it is naturally isolated or isolated by human activities, that number of species represents a balance between the number of species that immigrate or colonize that habitat and the rate of extinction of populations or on that piece of habitat and so, try to make sense of this.

Those two curves that are coming down from the upper left represent colonization rates and they are showing the relationship where the number of colonization is higher for islands with nearby islands. This means islands that are near to a source of species, like a nature continent. The curve is lower for those that are further away. Extinction, on the other hand, is higher; more extinctions on small islands because population size will be smaller. The curve is lower for large islands. Where that colonization curve and extinction curve intersect, would the number of species you would expect to find. So for example, here is the highest number of species that would be where the near and large island curves intersect. The smallest number of species would be found on those islands that are far from a source of colonists and they are very small.

Well, this was a very interesting theory, it was put out in the 1960's, but it has not, unfortunately, held up too well to scrutiny. When you really look at it, there have been very few cases where an equilibrium number of species determined by these two factors has been borne out. However, what this theory did was get biologists and conservationists interested in the effects of habitat size and habitat isolation on species diversity, and these are tremendously important features. Some of the early detractors of this theory of Island biogeographic theory pointed out that it does not necessarily apply to all species. On the other hand, at the same time, there was evidence accumulating that, in general, in this top graph is the percent of the fauna extinct for birds on the California Channel Islands in relation to population size and you can see that the larger population sizes, the extinction rate, the percent of the birds that have gone extinct is much lower. As you go down in population size, with smaller populations, you have more extinctions, and so this can be related to island area. There are birds on Northern European Islands, the larger islands have lower extinction rates than the smaller islands up here.

Other kinds of evidence was accumulating on continents to support this kind of theory about extinction rates being higher on small islands. A number of studies beginning in the 1950's proceeding mostly through the 1980's, but they are still going on, have shown that many species of birds are only found on larger pieces of habitat, and they are missing in what might seem to be appropriate habitat when those pieces of habitat are too small.

This is one example of the kind of relationships that were shown for birds and this is mostly from the eastern deciduous forests where a lot of these studies were done but these are all common birds of the eastern deciduous forests. These are area forests, these are in hectares and hectares are two and a half acres, going from .03 hectares to 3,200 hectares. This is the probability of finding a breeding pair of one of these bird species on a block of habitat of these various sizes and you can see the probability eases measurably as you sample larger blocks of forest. Again, these are all birds that you would expect to find in these forests but they are not found. Drawing on these kinds of studies, a biologist named Jared Diamond, in 1975, proposed the rules for design of nature reserves. What he was suggesting here is that large reserves, one large reserve is better than several small reserves of for the same total area. Reserves that are close together are better than those far apart. Reserves in a compact pattern are better than those strung out, reserves connected by corridors are preferable to those that are disconnected, and relatively round or otherwise compact reserves are better than long narrow ones that have a lot of edge, have a lot of habitat edge.

Now again, these rules were built from experience, largely on birds, mammals, and a few other kinds of organisms. Dan Simberloff, an ecologist in Florida and several others, immediately pointed out that there were many species that these rules did not apply to. Many plants, many insects, and even some kinds of birds did better in different kinds of configurations than those suggested as better by Diamond in some cases. However, this was answered by Jared Diamond and some of the other defenders of these rules, by the observation that the kind of species these people were thinking about (that did better, in say, in small reserves versus large reserves) species that really are not threatened by human activities. There are species that do great in developed landscapes, whereas the species we need to be most concerned about tend to be those that require large, unfragmented, connected habitat.

Okay, back to the practical side of things. This was all going on mostly in the scientific journals, from Shelford's work beginning in 1917 all the way up to Diamond's applications of Island biogeographic theory. This was not really hitting the street much in conservation. During this time, conservation was pretty much proceeding within the same kind of monumentalism direction that it always had been, but with more of a recreational spin on it. Most of the wilderness areas for example, that were established first in the 1960's when the Wilderness Act was passed in 1964 but also through the 1970's and 1980's, even up into the 1990's, are high elevation, isolated pieces of habitat. They are not the areas that are representative of the broader landscape, but they tend to be those areas that are actually poorest in species number, with few species. Generally as you go uphill the number of species declines. So in practice, the kind of areas we are setting aside for conservation are set aside for recreational and scenic reasons, not for biological reasons and they did not make a lot of sense biologically....with some exceptions.

Also during this period in the late 1960's we had an Endangered Species Act. First one version in 1966 and another in 1969 and now the version we have today more or less was passed in 1973 with amendments since then. The Endangered Species Program in the United States started right out focusing on those species that are extremely rare, which makes sense because they are the closest to extinction. An example is the California Condor, which went extinct in the wild, with the last few individuals put into a captive breeding program to try to raise them in a more sheltered environment so we could return them to the wild. It began to eat up a fair amount of money; we have spent over a million dollars annually on the California Condor Program, with still no assurance that we are ever going to see condors back in the wild as a viable population.

We now do have condors in Arizona as you know, and in Southern California. Whether they are really going to be able to last is still an open question. Now of course I hope they do, and I personally think the money was well spent. But when we have endangered species lists numbering literally in the thousands now, obviously we cannot do this kind of intensive effort for all species.

Furthermore, as it became very evident during the Northern Spotted Owl conflict in the Pacific Northwest, sometimes you do have conflicting societal goals. The goal of protecting species and nature on one hand, the goal of providing for a viable economy on the other.

Now it turned out this was really kind of a false choice. Even though the issue was framed by the press as owls versus jobs, it turns out that the Pacific Northwest has the lowest unemployment rates now in the country and a blooming economy, and all that has happened since we started protecting forests for the Northern Spotted Owl. So that owls versus jobs dichotomy was really not accurate. But nevertheless, it did alert people to the fact that there are tradeoffs in conservation, sometimes tradeoffs that could amount of multimillion dollar economic decisions.

Recognizing that we do not have enough money and enough willpower to protect every species one by one as it becomes endangered, people began to think that maybe we ought to be more proactive. Maybe we ought to go beyond endangered species and start thinking about protecting habitats and multiple populations of many species before they get to the brink, when they need something as intensive as an Endangered Species Act kind of approach.

This does not necessarily suggest that we forget about Endangered Species, rather it suggests that we augment Endangered Species Act kind of projects with a more proactive kind of conservation planning. That kind of brings us to where we are today. In fact, what we are trying to do with Habitat Conservation Planning and other ecosystem level conservation acts is really spelled right out as one of the major goals, the first stated goal of the Endangered Species Act-- to provide a means whereby the ecosystems upon which Endangered Species and Threatened Species depend may be conserved.

Many people kind of forget that this is, in fact, the first stated goal of the Endangered Species Act, even though we have tended to focus in practice on individual species when they are at the brink. It is noteworthy though that this is the only time that the word "Ecosystem" appears in the U.S. Endangered Species Act, in the goal statement of the preamble, and so no direction was ever given by Congress to the agencies on how they might actually implement this broad goal.

One way it might be implemented, of course, is through Habitat Conservation Planning. Over the last two or three decades that Conservation Biology has started to make real contributions to conservation on this continent, we have seen a multitude of different approaches suggested. Most of them I think though fall into three major groups. The first approach , what I might call special element mapping, is kind of the approach that the Nature Conservancy pioneered---mapping locations of rare species, rare plant communities, and other special habitats. Another approach is representation--- and again, this is what Victor Shelford's Committee of the Ecological Society tried to do long ago; to get a network of areas representing all of the major ecosystem types in North America established. We see this being followed today with the Gap Analysis Program, sponsored by the U.S. Department of the Interior.

The third major approach is Focal Species Analysis. This is where we look at the needs of particular species. What I do is go through each of these and offer some examples to show you how they might be applied, but I want to emphasize is that these three tracks or streams have usually been applied separately, in isolation from one another. That makes a big difference, because one comes to different conclusions and different sets of priorities, depending on which of these tracts tracks that you follow. Someone interested in rare plants or rare reptiles or whatever we might name, we will come to a very different list of conservation priorities than someone who is using an GAP analysis approach or someone who is looking at a population viability of say Sonoran Bighorns or Sonoran Pronghorns or Desert Bighorn Sheep. Very different kinds of priorities will merge from these three tracts tracks.

Now I am going to provide examples in large part from a study that some colleagues and I have recently completed for a region on of Northern California and Southwestern Oregon where we have tried to combine these three tracts tracks of conservation planning into one comprehensive approach. Now I would like you to be thinking about how you might apply these kinds of approaches here in the Sonoran Desert. I would not be so presumptuous to talk to you about what should be done here in the Sonoran Desert, not being native to this area and not having conducted any research in this area myself. But I think you will find some parallels between what we have done and what other people have done in some other areas with what might be done here.

First, special element mapping: here we looked for those special things in the landscape. We looked for what some biologists have called hot spots, places of concentrated conservation value. This is in line with the generalization that biodiversity, however we measure it, is not distributed randomly or uniformly across the landscape; rather it is concentrated in particular areas. These areas have been called hot spots. So for example, here in the Amazon Basin, biologists familiar with a lot of different kinds of plants and animals got together and they mapped out areas that contained high numbers of species that were found nowhere else (these are endemic species). The red areas are areas where the most endemic ranges overlapped, okay? So it makes sense that we would focus on these areas. There is one problem with this approach, you might be able to recognize right off. We have not really surveyed the entire Amazon Basin, have we? It is a big area. These hot spots tend to correspond with the locations of biological field stations in or other areas that have been surveyed. So there are some problems with this approach, and that is why we need to complement it with other approaches, as mentioned.

In the Klamath/Siskiyou Region in Northwestern California/Southwestern Oregon we have a large number of endemic plants in particular. There are 280 plant taxa at the subspecies level that are found nowhere else in the world. For the temperate zone, this is a very, very high level of endemism. So what we did is plotted out the locations of these endemic and other rare species based on Heritage Program records across the study area, and weighted those records depending on the level of imperilment, with those that are considered by the Nature Conservancy to be globally and critically imperiled weighted higher than those that are only imperiled at a state level and are more common globally.

A close up is shown here, we did this within a one kilometer by one kilometer grid and so the darker colors have more of these rare species including the endemics concentrated. As you can see here, this is shown in relation to some of the existing protected areas. We found that many of these rare species hot spots at this scale fall outside of existing protected areas. In fact, about 82% of them fall outside of the strictest category of protected areas. This tells us that we have not done too good a job in this region protecting rare species. However, because of the problem I mentioned earlier. not all possible locations of these rare species have been found because of incomplete survey; we might want to protect those habitats we know are associated with high numbers of rare species. In this region, they tend to be the serpentine habitats. The Klamath/Siskiyou Region has one of the highest concentrations in the world of a particular kind of rock, altermasic ultramaphic rock such as , serpentinite and (?) that tend to be associated with large numbers of rare species, and that is because they contain what are toxic levels to many species of certain minerals such as magnesium and nickel among others and they contain very low levels of calcium and some of the other essential nutrients. So only a very specialized species are able to persist here, in areas where they receive less competition from the dominant species. We mapped out for the area in the Klamath/Siskiyou Serpentine Habitats as valuable in their own right even if we have not found any rare species there yet.

For aquatic species this kind of mapping approach does not work too well because these species are distributed as stream organisms in a linear fashion. In this case, Salmon are connected to the ocean so you have to look at it real differently. You have to look at watersheds. It turns out in our region there are a number of species and runs of Salmon and Steelhead Trout that are imperiled to one degree or another. So we mapped out the watersheds where they occur and located those as shown in the dark blue. They have the highest number of these very endangered stocks. Here, we weighted those stocks and runs of Salmon depending on how critically imperiled they were and mapped out those watersheds.

Also it is good to look at, in this approach, rare habitat types or ecosystems. Such things as Oak Savannahs, for example, are endangered in this ecoregion. They have declined significantly since European settlement, but old growth forests of all types have shown major declines. So this maps shows the old growth forests presently existing in the region; according to the best available data.

As I mentioned, this special elements approach tends to focus on the very rare things. It does not necessarily assure that all species and habitats will be represented. The representation approach tries to assess how well species groups or particular habitat types are represented within existing protected areas. The Idaho Gap Analysis, for example, determined that alpine and sub-alpine communities are pretty well protected by wilderness, national parks and reserves, but if we go downhill just a little bit to the montane forests, there are some classes of montane forests like the Orange Cedar and Hemlock, the Olive, and the Ponderosa Pine Forests that are not very well protected and are being logged very heavily. This immediately tells us those are the areas where we might want to concentrate some future conservation activities of one sort or another.

In the Klamath/Siskiyou we actually combined a kind of vegetation Gap Analysis which is this here, which the federal program uses with a physical habitat and classification based on temperature, precipitation and soil sloe properties. Because the vegetation maps produced by the Gap Program are based on the dominant overstory vegetation, they do not tell you much about those taxa that are more closely tied to the substrate and, perhaps in many cases, very much affected by the variation in precipitation and other variables across the gradient over in which these vegetation types are distributed. So here is our physical habitat classification; a lot of work went into this-- it was a Master's Project and took about three years. These are the vegetation maps from the Federal Gap Analysis Program and when we combined them, we came up with 215 habitat types defined by this combination of vegetation and habitat gradients, which I will not show because it is a really scrambled. What I will show is this map that shows present condition. The white areas have less than 10% of those habitats found in that area which are not within protected areas currently. Going all the way up to the black where 50-100% of those kinds of habitat are currently found within reserves. This again shows us where some of the priorities are in terms of representation. Many kinds of habitats, especially low elevation areas with good soils, are unrepresented in protected areas.

Both of those two approaches I just briefly reviewed, special elements and representation, tell us a lot about the locations in the landscape where we might want to concentrate our conservation activities. They do not necessarily tell us about the configuration, the design, necessary to maintain species and ecological processes over a long period of time.

Here we have had to look in much greater detail at the needs of some particular species. We call these focal species. We could spend have an entire day or more spent just talking about focal species, so I am going to have to be very quick. A very interesting paper published in 1997 in Conservation Biology by Robert Lambeck of Australia defined four categories of focal species; these are species that are tied to certain characteristics of the landscape that you have to maintain. For example, area limited species are dependent on a particular area of habitat; you have to have a large enough block of habitat to maintain their populations. They are very sensitive to reductions in that amount of habitat available. Dispersal limited species are those that are very restricted in their mobility, they have a hard time getting across the landscape or else they might encounter mortality, say being struck by vehicles when they try to move across the landscape.

Resource limited species are dependent on particular habitat structures or resources that are at least sometimes, in critically short supply. An example would be secondary cavity nesters such as your Cactus Ferruginous Pygmy Owl which do not construct their own cavities so they depend on cavities constructed by other birds. They also would include bats and fruit eating animals in this regions. Hummingbirds are also dependent upon particular resources that are, in some years, in very short supply.

Process limited species are sensitive to timing, intensity or frequency of some natural process such as disturbance regime like fire or flooding. If you try to determine the species that fall in these categories and try to select those species in each category that are the most sensitive, those combined might tell you suggest a way to keep all fauna in the landscape.

There are some other kinds of species that I think we also need to look at. Keystone species, for example. Probably some of you have heard of this term. These are basically species that have a very large impact on the overall diversity of the community, as such that if their populations are maintained, they help create conditions that provide for many other species. Cavity excavating birds, woodpeckers for example, are an example of one of these Keystone species. We might also include large carnivores that are as Keystone species because they regulate the populations and distributions of their prey, which in turn affect vegetation and the habitat for many other species. Therefore, identifying these Keystone species which have a disproportionately large effect on the community is important.

Now I mentioned that when I talk about special elements and this concept of endemic species, and species with very narrow distributions, most of them could probably be picked up by the special elements mapping kind of approach. Also, we need to consider some very rare species individually because their requirements are so narrow, and so restricted that we need consider them individually or that we are going to lose them soon unless we give them special attention. Then there are always special cases; for example a genetically unique population of a given species, or a species that is very popular with the public.

We are developing empirical models of habitat quality for focal species , which we then validate. In the case of the Pacific fisher, we validated models by going out and setting out sooted track plates. In this case, our preferred model was validated at a level of about 80%, which is very good. We were able to predict where the high quality habitat was for the Pacific Fisher in the Klamath/Siskiyou region. We found, as often is the case, that it was not very well represented in existing reserves. That is not a real good slide but the major point stands.

There is also talk of reintroducing some of the species that have been eliminated from the Klamath-Siskiyou region, such as the Gray Wolf. We are in the midst of a study there to look at habitat suitability for Gray Wolves across an expanded study region ranging from Sonoma County up to North Central Oregon and across the Sierra's, and where we are looking for those areas that offer in this slide, the greatest security to wolves, and those are the areas defined by green. These are areas with low road density, low human population density, and far from existing human settlements. We are also looking at prey populations and so on and we are identifying particular corridors that might link together our region with some other regions. This is the kind of thing you can do knowing something about the habitat requirements of these animals. Then you can go out and verify it really works by setting up survey stations. Now for the wolf, we are validating these models actually up in the Rocky Mountains where there are existing wolf populations and assuming that they will transfer pretty well to the other study region.

These three approaches: special element mapping, representation, and focal species analysis ideally should be integrated when you get down to the stage of actually protecting certain areas of the landscape. We put together a proposed reserve design for the Klamath/Siskiyou Region based on a combination of these three approaches. In proposed GAP ones, this simply means the highest category of protection according to the Federal Gap Analysis Program capped to the moderate protection under those same criteria so this is what we are more or less suggesting.

Now finally, I wanted to address some issues about how we decide how much area is needed and in what kind of configuration. I am just going to basically review some of the empirical generalizations or principles of Conservation Biology. Generally, you cannot answer this question in an abstract way. These generalizations take us only so far. You have to do the necessary research. Every region is going to differ. Furthermore,protection does not necessarily mean hands off, in fact, it usually means restorative management, active management of various kinds to maintaining those necessary habitat conditions. Some of the principles of Conservation Biology and I mentioned earlier,--- the reserve design rules that Jared Diamond and others had proposed. Some of those have withstood the test of time while others have not.

What I am going to go through now are the empirical generalizations that have pretty much withstood the test of time. One is that it is good to keep species well distributed across their native range; do not let them shrink down to just a portion of their range. There are many reasons for this, some are genetic. Those populations that are towards the edge of the range may be genetically distinct. Also, we cannot ever count on the rest of the range being protected. The pygmy owl is an example of that. Certainly there are more pygmy owls-- we do not know how many and we cannot be assured they are going to persist there. It is possible that there are some unique adaptations of the Pygmy Owls in this area, on the edge of their range.

Probably the best accepted generalization, after the species area relationship which it corresponds to, is that large areas of habitat are better than small blocks because large blocks are going to have larger populations of your species of concern. We know through a number of studies that small populations are subject to a lot of different threats. Mike Gilpin is going to be talking more about this in his lecture so I am not going to cover this in any detail.

There is some data very similar to what I showed you earlier. In this case, the grassland bird is showing how the probability of protecting and finding those species increases as the size of the habitat increases.

Another related principle is that blocks of habitat close together are better than blocks far apart. The idea here is that if you have them close enough together they function as one single unit for the species concerned.

What we mean by close together has to be spelled out, because for some organisms, these two patches of forest are close together. Birds can easily fly over the highway. However, if you are a lungless salamander or , if you are a small forest rodent, those two patches of forest might as well be a thousand miles apart--- they are not going to cross it.

Another related idea is habitat in contiguous blocks is better than fragmented habitat. A lot of studies showing that fragmentation as shown here leads to impoverishment of the habitat. Where exactly the threshold is when a landscape becomes too fragmented is still something that remains to be worked out in many individual cases.

For example, is this too much fragmentation here? Or do we have to wait until they get down to here? That is something that has to be studied uniquely in every case.

Interconnected blocks of habitat are better than isolated blocks. There is a lot of discussion in Conservation Biology about corridors. Conservationists often include corridors in their designs, but it is possible that poorly designed corridor, for instance a very narrow one as shown here, could do more harm than good because it will favor species that thrive in disturbed habitats at the expense of those that are more sensitive to human disturbance.

What we are concerned about is not a corridor per se, but rather functional connectivity of the populations. This has to be defined pretty much species by species. Connectivity might be supplied by a corridor, or in some cases, it can be supplied in other ways. A recent review by Paul Byer Beier and myself of the corridor literature found that most of the properly designed studies of corridors found that they do, in fact, provide functional connectivity in to one degree or another. We have one of the fathers of metapopulation biology in the audience, Mike Gilpin, (and he even has "Metapop" for his license plate), so I will let him tell you more about this but this is one of the arguments for why we need connectivity--- to allow organisms to recolonize areas where we had populations go extinct. Mike will tell you more about that. I going to skip over these in the interest of time. Basically, we know enough now about connectivity in most cases to make a good start for maintaining a connected landscape. The details in many cases do need to be worked out through further research.

Another observation is that for species sensitive to human activities, blocks of habitat that are roadless or otherwise relatively inaccessible are preferred to those with a lot of access. There are many reasons for this; for example, roads are sources of mortality for a number of organisms, such as wolves in the Rocky Mountains. Y ou might expect the Canadian Rockies to be a pretty secure place for wolves. In fact, highway mortality is the largest known source of mortality for wolves in the Canadian Rockies, and it is even worse in the national parks because there are more vehicles traveling through them. Snakes are also very vulnerable to road kills.

Roads also provide access to poachers and collectors, and not just the wolves are threatened by this, but snakes for the pet trade, orchids and cacti for the horticultural trade and so on. That kind of poaching is enhanced by roads and other access.

Now I have been talking mostly about species specific rules, the last few were built from observations of species and how they respond to landscape configuration. We are beginning to see that maintaining viable ecosystems, however we might choose to define them, is in many cases going to be more efficient, economical and perhaps notably more effective in than a species by species approach. We need so in my view, to find a way to reconcile our rich knowledge based on observations of focal species with the knowledge that we have to start managing for entire ecosystems.

I am going to skip over a couple of these because I am about out of time. Some zoning rules. I am going to leave you with one point:

Again, how much is enough? That question not only applies to how much of the land you need to have in a conservation system, it also applies to how much research, how much study is necessary before you finalize the Conservation Plan. One rule that our Scientific Review Panel from the Coastal Scrub Plan, which included myself and Mike Gilpin, agreed on is that data collection is going to take awhile but in the meantime, the less data or the more uncertainly you will have, the more conservative your plan has to be. The margin for error is reduced, so it is in everybody's best interest to get a lot of information. At some point you have to act, but in the absence of complete information you have to err on the side of protecting more than enough rather than protecting too little if you want to meet the biological goals of your plan. With that I will close. Thank you.

I have a brief advertisement. I brought along three copies of my book on Science and Conservation Planning, I sold one already and I am selling them for a discount price of $20.00 so if you would like one I have two.

QUESTIONS AND ANSWERS:

Dr. William Shaw: We are going to take a few minutes for questions now and then we will take a break. We are going to set up some additional chairs for those of you that ran out of space. There will be additional time at the end of the whole session to have questions as well.

Question:Do we have some kind of interim guidelines during the phase of research and data collection before the final plan is approved?

Answer:In the example of the Southern California Sage Scrub, what we did is come up with some interim guidelines and they were to lose not more than 5% of the Coastal Sage Scrub habitat during the planning process. But it was not just a simplified 5% cap, what we produced is a decision tree where you go through and you compare pieces of habitat in terms of their known biological values, their size, their isolation and other factors to channel development away from those patches that are likely to have more biological value and channel development into those areas that are very small, very isolated, that are degraded by other activities so that we kind of maintain our options during that interim period. That is a very difficult thing to do. I think our approach worked pretty well in the case of the Coastal Sage Scrub, I have heard of some abuses where our decision tree was not really followed but I think in most cases, the jurisdictions show goodwill and try to follow the interim guidelines.

Question:How long was that period?

Answer:Well, it kind of lingered on. Mike, you might know more than I do how long that research period lasted.

About five years.

We originally were hoping it would be two three years but it turned out to be about five years.

Question:How does sustainable cattle ranching conform to the presentation today about a landscape management through biodiversity?

Answer:I think it is a landscape specific kind of issue and I would not pretend to be familiar enough with your local situation to give you a definitive answer to that. The kind of approach that I worked on elsewhere has established different zones basically where those areas of highest biological value are usually recommended for the strictest protection which in the case of a desert or grassland ecosystem would usually be, not always, no grazing by domestic livestock. For other zones where grazing by livestock, where sustainable forestry where a number of other extractive kinds of uses would be perfectly appropriate so you really have to look at the site and you have to look at how the livestock are being grazed. We know some examples, and this is sometimes a misused notion, but where livestock can be a management tool. Examples include areas that were adapted to grazing by native large herbivores, those native large herbivores were extirpated, you cannot get them back at least in the short term and so livestock, if managed correctly can fulfill those roles. However, we know of many other cases where livestock are definitely causing problems so it really has to be, I am sorry to have to put it off on you, but it has to be a case specific kind of issue. In a particular area, particular grazing regime, is it or is it not compatible? We have to ask that question case by case.

Q:Why should we try to preserve the status quo when nature always changes?

A:That is one that we hear often, it is one that is often brought up and it has never had a completely satisfactory answer, but it really has to do with rate and scale. The rate of which we are losing species worldwide today has exceeded all rates we know of for the last sixty-five to six-seven million years.

Q:What is that based on?

A:It is based on pretty damn hard data. We have good fossil data of the cretaceous extinction of man, for example, and we have some pretty good extrapolations on current rates of species loss. We know that it surpasses anything we've seen since civilization, since the agricultural revolution or the industrial revolution. We have hundreds of species documented that have gone extinct, even on this continent and they seem to be going extinct of course, more rapidly in the highly species rich tropics. S so it is something that 99.99% of biologists would agree that we are in another mass extinction event and the question is whether we are going to allow that to happen, whether that is something we are going to live with. In the past, recovery did occur, recovering species numbers (, you can never get those same species back given current technology) but recovery of species numbers did occur after these great mass extinctions of the past, but they took between ten and twenty million years. so Ddo we want to wait ten or twenty million years for our descendants to have a complete bountiful world again? and I think Mmy personal philosophical response is that I think we have a need for a stewardship ethic, we have an obligation to try to maintain species that we see here today that would be around without our harmful activities. There are some species that are on the way out naturally but that rate might be one or two per year compared to what is now on the order of 20,000 or 30,000 species per year ,so it is just a difference in the scale.

BREAK

Dr. Shaw:We will take a brief break now. Please plan to be back in your seats by twenty minutes after and if any of you did not get the handouts, there are some additional copies in the back of the room.

RECONVENE

The session reconvened at 10:20 a.m.

INTRODUCTION: DR. SHAW

I would like to introduce Michael Gilpin. He will present a heavy-duty quantitative analysis into the topic you see on the board which is Population Viability Analysis which is an extremely important aspect of Conservation Biology in evaluating conservation strategies. He is widely published on this topic and on the topic of metapopulations which I am sure he is going to talk about today and he is a preeminent authority on these issues and we are really fortunate to have him here today.

BASIC MODELING APPROACHES TO SPECIES VIABILITY: MICHAEL GILPIN

So I asked what is boot camp and Maeveen said, "Well you know, they don't exactly have the same background you normally speak to, " and I said, "Well at least they know calculus or at least they remember calculus." So Maeveen said, "Well, see try to keep this lecture to sound (intelligible to someone) like a real estate developer, a lawyer or a (?). I was on the recovery team for the Desert Tortoise and they said I was gambling and Maeveen said, "Yes, gambling." So I am going to give you a lecture on species viability analysis and I am going to try to do it metaphorically and graphically without any calculus. You have the Sonoran Pronghorn, Pygmy Owls and there are going to have to be some PVA's done in this process of planning for Pima County and the purpose of the lecture I am giving you today is to give you some real gut feeling for the power and especially for the limitations of PVA because PVA is not magic, it is part of the process but you guys have to be somewhat skeptical about the answers that PVA gives you. I am going to appeal to your intuition, I am assuming all of you have gone to Vegas and lost in some sense, you lost as much money as you wanted to play with or you have lost all of your money so the metaphor of gamblers or a player playing a game and losing money is what we use for the viability of small populations.

How long will a player play the tables before that player goes extinct? What is the best strategy? If a player is losing money, is there a way to change the strategy whereby to prove the odds of survival so these are some of the things I am going to point out how the mathematical analysis pertains to these things and link them up with small population biology. Now, like any computer geek pretending to be a biologist, my approach is through a website and you have access to this website, there will be a link from the Pima County Conservation Plan webpage and there is an address floating around here. This is actually coming locally off my MacIntosh so PVA introduction, we are going to think about gamblers, we are going to think about, you know, you go to Vegas there are games you can play, how long you expect to last, how many free drinks are you going to get while you play, da da da.

Now, as I said you do have access to this so even though I go over these facts you can log onto the web and as long as you are using any 4.0 level browser, you can manipulate these things.

So here is the game of craps and it is not the whole game of craps only the pass field. The way the pass works is that when the table is in the odd condition, the next throw of the dice is going to be the coming out throw. If you throw a two, a three or a twelve, it is craps and you lose your money immediately. If you throw a seven or an eleven you win immediately. If you throw one of these numbers, four, five, six, eight, nine, ten that number becomes the point , there is an ivory disk here the croupier will turn this over the on condition and place it on where the point is and then the betting proceeds. You keep throwing the dice. If you make your point you win, if you throw a seven first and call seven out then you lose your money so all bets, all pass bets are resolved with this mechanism and you can play the game by pressing this button, throw dice.

The first time you throw, ah! Bad number! Throw a three it is craps, we are a loser and our money would start at ten and so it now at nine. We will play again, throw the dice again and we get a six so this disk is now over the six and the on position now the win-loss is resolved either by throwing a six or by throwing a seven. You keep throwing, we throw a seven and we immediately lose. In two steps, the steps are here, we have gone from ten dollars to eight dollars. Now what this program does is it allows us to speed up the investigation of playing craps and there is a button here that says "play until broke." So I played until broke and it took me 2,300 steps before I went broke with ten dollars. You can get a lot of free drinks with that.

So we reset, 900 is real good too. Reset, play until broke at 300, that is still good. Fifty-two, yeah. Now the fastest you can go broke would be ten steps, you would lose every time. So now we do this and we get a sense that there is a lot of variability of a small amount of money persisting at the crap table. It can fifty steps or it can be 2,000 steps. Which is it? We cannot put a real answer on that until we do lots and lots of these things and come up with a probability distribution. Now I am only going to do 100, the computer can do 10,000 but it takes a few seconds to do this so here is the kind of mathematical analysis one can do on the game of craps. We have now started with ten dollars each time, we just keep on playing and playing and playing. A couple of times out of 100 trials will go at least 5,000 steps before we go broke.

Most of the extinctions are early on and that is what these numbers are, each of these is a division of 100 steps. The mean time to extinction is 743 steps, however, most of the trials go extinct before the mean and this is very typical of PVA work on small populations. The expectations are that most populations is 80-90% of the cases will have gone extinct before we move onto extinction, we get a lot of the mathematics we currently have predicts mean time to extinction so you have to understand that if you are gambling on this thing, maybe half of the cases will have gone extinct in the first 200 steps. In fact, maybe 10% of them will have gone extinct in the first 50 steps and some of the rules are not rules but guidance that comes out of PVA analysis is that you want about 95% probability persistence per 100 steps or 100 years in the case of species. To get 95% you are not going to get that starting with ten dollars so you need a bigger population of money to have any chance whatsoever of getting 95% probability of persistence for 100 times that.

Now let's check to see if this a robust answer so we can do this a couple of more times. And it looks like it is a pretty robust pattern. One hundred trials is roughly enough, 600 to 800 is the mean and this distribution does not change too much, of course it is a little bit ragged out here because these are just small sample points but the general curve is the exponential decline. See, I truncate the thing and here is actually the ones that go even longer.

This is what analysis can do to the stochastic and stochastic is a word meaning involving chance and all things in nature involve chance so this is what mathematical analysis can do for a stochastic process which we understand perfectly and this is the point. We understand and can program the rules of this process perfectly. Chance comes in through the throw of the die, this chance comes in through weather events, disturbances, outbreaks of insects, all these things were chances. .It has a skew out to my right on the board. Given that we understand this perfectly, we can start to ask some questions about strategy and about change of rules.

Now I am just starting a baud experiment that we might do is that we might say, "Well, I have a carload of graduate students and we are going off to do field work and they are whining that they want to play craps with ten dollars," so what advice did I give to my graduate students? Shall I say, "Let us all be chummy and play the same bet at the same table? Or should we all play different tables? Now if we all played the same table and we all followed exactly the same distribution we would all go extinct at the same time which may have some advantage. But if you had the excuse to play different tables, the probability that at least one of them persists is much higher so this is a hedge your bet type of approach where you spread your risk over different environments, the important fee here is that the roll of the dice is different at each of the tables. See if it were the same type of dice on the video display monitors or something like that at all the tables it would go back to being, "everyone goes extinct at the same time."

This turns out to be a very key thing in population viability analysis, are your patches seeing the same environment or are they seeing different environments? If they are seeing the same environments, it would be refining some of the rules that Reed was telling you about but the rule is, if the environment is the same everywhere, aggregate everything into a single pass. But if each pass has a different environment and a different set of prey/predator then it is better to spread your risk over multiple patches. This is a case by case analysis because each species perceives the environment in different ways.

Now, see one of the things we can do is start with more money. If I start with more money, the distribution time would lengthen out so you are always better off when you have a larger population or stop when you have a small population, that is why you are going to pay attention to those populations that are currently much reduced, those are the ones that have much higher probability of extinction.

Now what is going on here is that Las Vegas is not a charity, every gamble you play it has a negative growth on your money. So every one of these things will always go extinct. If there was the possibility of a single trial in my run not going extinct, my computer would still be running so every one of these things managed to reach extinction after some numbered steps and that is because the expectation is for each dollar you bet at craps, you expect to get 98.7 cents back. That is the mean. So the mean rate of growth is very important and now many of the species we deal with Conservation Biology, the condor is a perfect example, you can look at the graph of the condor and it is going down, down, down, down and they were long lived animals and they had to be five-years-old before they could reproduce and they were eating coyote poisoned bait, they were getting electrocuted. It is a given that they had to live forty-five years to start to have chance to have a chance of replacing themselves, they were not making it to forty-five years and here is a case of the population going down, down, down, down so if you cannot reverse that, it is hopeless. But even populations that have a positive rate of growth can go extinct and I have a demonstration here on the next screen.

Due to a ceiling, they can only get so high and once they get that high, they start bumping into ceilings and cannot escape and you still have all the land and forces acting on them so they can have a run of bad luck and go extinct from that point.

Now what I have done here, there is some text you can read if you go to the website and so see as your bootcamp assignment, I want you to do some sort of structural analysis on the game of craps and some betting analyses and e-mail your results to Maeveen.

See, this is the normal game of craps and I want you to consider three different things, each of which has an analog in the real world of biology. See the game I have been modeling is where you bet one dollar at a time. Suppose as you get ahead, you feel excited each time you win, you have more than ten dollars you bet two dollars and when you have more than twenty dollars you bet three dollars so you scale your bet up as you have more and more money. What impact would this have on tying to extinction? Now I am not going to tell you the answer, you have to go to the website to do this, but this is more truly the way biological populations work because as the numbers get higher the total rote is higher so a condor population of 60 is going to betting more offspring population than a condor population of ten.

Another thing is, suppose our gambler is playing here and suppose every time she gets to twenty dollars, her husband comes by and asks her for money to play his games. She will never get beyond twenty dollars, what does this do to her probability of extinction? Again, this is analogous to a pairing population, a small patch that never get beyond some total density. Suppose that she is playing and her husband periodically comes by every 100 trials to ask for a few of the ten dollars and if she does, he gives her a dollar so this would be like migration into a patch. What does this do to extinction? So these things are all perfectly defined problems on which we can do mathematical analysis. Hopefully this is the gut feeling that the bet is going to be used as the basis for what I am going to talk about next which is the real world. In the real world we do not know the rules, we have to guess at the rules. Someone said do a PVA on the Pygmy Owl, I would not have a clue on how to do a PVA of the Pygmy Owl, you have to spend a lot of time learning about the Pygmy Owl and sometimes, if there is not the knowledge available today, it takes years to get the knowledge. See, the knowledge being what underwrites see the rules which is what you would go into this kind of simulation model.

Given that you do not know the rules, there are two approaches. The literature obscures the difference between these approaches so there is all sorts of stupid argumentation about PVA in the literature now.

There are two branches of PVA, one of which is a time series approach and this is exactly like chart or technical analysis in playing the stock market. You simply have a gray out of the price of the stock and that is the only thing you know, you do not know anything about what Greenspan said, you do not know anything about the economy, you are watching the value of the price of the stock and you are trying to project that value dramatically forward in time to tell you whether it is a winning or losing stock, this is a timer series approach or what you can call a "statistical approach so you have some information and you want to draw a line through it and say it is going up or down.

The other approach is to do the science and learn the rules. I am going to quickly talk about both of these approaches and show you what their limitations and relative considered advantages are. All these things are the sort of games I have my students play them.

So here is a game where a population is declining, let's think of the grizzly bear. The truth is, the population is declining but we have to make an argument to the National Park Service or to the public at large that the grizzly bear is declining. The problem is, you cannot census the grizzly bear. If we could actually get the true numbers of grizzly bears you see yesterday, today and tomorrow we could draw a valid line through these census but even with something as big as a grizzly bear, we would have a tremendous uncertainty as to how many grizzly bears each year. See if they were all wearing radio collars that would be great, but even spending two million dollars a year it is hard to get a perfect census so what we deal with is a sample.

There are some who think that you can actually fly over and do aerial surveys on things that are out in the middle of plains and short vegetation, you can photograph them and get pretty good numbers but most things we work with, we have to sample. So here is a game that we play where we are going to take samples at two points in time and we are going to project what the population is doing. The population is really declining along the black line. See I have a 10% sampling deficiency here so this means that suppose we had Yellowstone. Suppose I go into 10% of Yellowstone and spot every grizzly bear that is there and I multiply that number times ten, that is how I estimate the total sightings in Yellowstone but the grizzly bear moves around and sometimes this area would have more dense sightings. So I have a 10% sampling deficiency, yet I have taken samples two years apart to do a trial. My real numbers are here and here, through the sampling process I get estimates of grizzly bears below and above here so after one year, I say the grizzly bear is increasing at 47% per year. But that is what I get from my sampling. I do ten trials, numbers all over the place, do 100 trials and this is not good enough.

The colors are not coming in, I can see it on my screen. See when we go back to one number you can imagine a line going between these two numbers. Now suppose I increase my sampling efficiency to 50% so I am getting a much tighter answer and one of the important things is the true growth of the population was minus 3% per year and when I sample with 50% efficiency over a five year period my sample estimates cluster around the actual estimate and it is only in the small percent, 12% of the cases am I falsely estimating the positively growing population.

Okay, this is real important. There are two things that I did to get better answers. I spent a lot more money to sample more thoroughly and I took a lot more time to do the sampling. Both of these cost you money. See the developers always scream, they say we have loans on these big plans they are developing and you know, can't you see they are paying the bank ten to twelve percent interest per year while you guys wait for this to come true but these are actual limitations. You could say, "Well go out and sample better," but some things there are reasons you cannot sample better. If you go out and sample too thorough you disturb the environment too much. These are the kinds of limitations you get when you play the project the time series game of PVA.

Now I have another game here, it is sort of the same game where you have a sampling efficiency, sampling efficiency and number of time steps over which you sample and these are in what are called text fields so you can change these numbers. See, this game works by selecting a growth rate. Now I have selected plus or minus 3% and what I am going to get here is with my sampling efficiency, see of 10%, there is an underlying trend line which is up or down at 3%, these are my sample points of one, two, three, four, five, six. I am going to hit one of thee buttons to guess whether this is a growing or shrinking population. Now this looks easy so I am going to guess that it is growing and in fact it is growing, I go to the next one and that one looks like it is growing. This one is going down. So these are my samples which look like they were going up and in fact, the first sample was way below and this sample is a little bit above so what a six year series and what the truth was, it is going down.

Again, if I stretch out this period or increase the efficiency of sampling so I am going to increase the sampling here to 90% and start a new trial. You see here there is very little error, the population is almost certainly increasing, there is very little sampling error about these points and when I guess I am almost certainly going to be right.

This is a very common way of doing PVA, see it has the statistical limitations that I just told you about. More importantly, there is no model here, there is no understanding the mechanism. From this you do not go to a recovery plan, from this you do not go to an HCP, this only is raising the red flag, this is going up or down. You do not understand the population so I never do these things, a lot of people still do these, but I tend to go towards the mechanistic model which is actually even harder but at least if you try and develop a mechanistic model you have some understanding which allows you to do what we put in a report, what if we shoot the predators, they are eating these guys. What if we put up better feed boxes, a lot of what if things that could be put into the model and you can run the simulation. Again, I am not saying these things are perfect but at least they are a tool that allows you to come to a consensus as to what might be a good strategy for dealing with this particular case.

This is slightly complicated, but look at the red line here. The red line is the plot of the number of animals you expect in the next time period given the number of animals you have today. So here is the animals you have today, here is the animals you have tomorrow and in this range between this point and this point, you expect to get more animals tomorrow. See, if you have these few animals today, this point is preparing capacity, this is a 45 degree line. If you have this number of animals today, you get the same number of animals tomorrow, the population is at steady stake, it is at equilibrium. If you are above this point, the animals you expect tomorrow are fewer than the animals you have today because there is not enough food for these animals. Their population is going to crash so this is the famous logistic growth model, this is what is used for harvest modeling. People try and harvest animals at half their pairing capacity because that is the point where they have the maximum resilience, the hunting pressure and things like that.

What I am doing here is doing a logistic growth model with pairing capacity and I am varying the growth rate so the growth rate here is one which means that it is 100% growth rate. See a growth rate of zero means the population would not change at all so I am giving you the population positive growth rate and I am changing the environment. I note everything with the exception of I do not know what the environment is going to be from year to year. This almost exactly now I guess to the craps model. Some years we are going to get bad rain, some years we are going to get good rain so the environmental variance, this is a variance measure on the growth rate. See, this also can be changed, the higher this is the more variable the weather is so you drag the mouse over these bars, let's get the environmental stochasticity low. See, as we get this low there is very little disturbance from year to year, the estimates cluster around the pairing capacity and that is what this histogram is. The probability of distribution for observing animals is the capacity plus or minus 5% with low environmental stochasticity. Now this is very important, the only thing I am going to change next is the variability in the environment, I still have a population with positive growth and a positive pairing capacity but now I am getting worse ups and downs and if I have dramatic fluctuations, then I get two or three bad ones in a row the population really gets driven down. Changing this, see I am actually going to drop the growth just a touch and see what happens. So changing environmental stochasticity to higher variance and what you are seeing here is a spread in the probability of distribution in animals and note that the mean of this distribution is moving to lower population sizes relative to pairing capacity. This is a strange mathematical result that very few people understand but it is easy enough to see here.

So we start to stack up the population at low densities and some of the chance occurrences drive the population extinct so out of 300 trials we are getting 20 times this before the population goes extinct. Understanding the degree of environmental stochasticity is equivalent to understanding the dice that gets rolled in the craps. The species varies for the same species in different environments, but this is a key thing. Environmental stochasticity is all the key in doing population viability analysis, understanding where it comes from, how it impacts, what you might do to mitigate it, etc. I do not have time to get more deeply into this, I am going to now going to talk about metapopulations.

I have done a lot of work on metapopulations so now imagine the following. We have a (?) here, we have it in this color which is almost impossible to see it. I have six patches, six habitat patches of different sizes and different adjacencies, different distances between them. I can keep track of distances. Now, the data that went into parameterizing this model come from South Pacific birds. Jerry Diamond and I did about a ten year series of work where I took all the information he gathered from birds and fit models of area dependent extinction and distance dependent dispersal. These things are of the character birds which might be of the character butterflies but is not at all necessarily the character of small mammals on patches of the forest floor, but it is plausible.

The point of this model if you could do relative investigations, see it would take a lot of information to quantify this absolutely but in the relative sense you can change the configuration of the patches and see what it does to the persistence time of the metapopulation. When I hit simulate, you see the patches wink on and off, see the big one winks off fewer than the small ones, the small ones this small one for example winks a lot. This graph plots the number of patches occupied, this graph which moves down the page is patch zero, patch one, patch two, patch three, patch four and patch five. The black bar represents occupancy, this point represents an extinction event and so this patch during this period of time is extinct, it is recolonized and it goes extinct and this looks like something which is not too viable. You see, most of the runs for 400 time steps are ending up with all the patches extinct. So then we can do some things, we can say "Well, what if we move this patch over here?" So now we have better connectivity and see, nothing else has changed but we do have better connectivity Persisted, persisted, extinct. See moving this patch over here, when it was sort of isolated out here it would usually go extinct and stay instinct and did not help the system. Moving it into here it first of all had a higher probability persisting. Secondly, it served as a source patch for these four adjacent patches so when this one would go extinct there would be an extra probability that conditional upon this patch being occupied you could get a dispersal colonization event that went from this one to that one.

So metapopulations are very much dependent on size and location of patches and the rules that Reed was discussing earlier are based on models like this, but this is a single species model this is not a model that is talking about biodiversity of the Amazonian Rain Forest, this is a model that you would apply to one species at a time which allows you to do this analysis. This type of model allows you opportunities to add patches so I add a patch over here and they can move it in, I can make it bigger, get this one closer. Notice now that these black bars are more continuous so this is a tool which allows single species reserve design.

Q:Can you change the shape of that?

A.No, this is sort of a toy model that is used for student demonstrations, boot camp stuff, but the real world stuff I have done, I have ragged edges.

In fact, a lot of the work has now gone to actually subdivide each of the patches, but the rules still remain the same about dispersal over bad habitat.

I am going to finish off with a real world example. Again, I do not have time to do this fully but this is actually one of the things written up in Quammen's book, Song of the Dodo, in fact this graph is almost exactly in Quammen's book except it was a true basic program at that point, now it is a wonderful job applet. So in 1987, I gave a talk at the 1985 meeting that Soulé held that led to the 1986 book on population viability analysis which was a term that was coming into vogue and the Fish and Wildlife representative, Jim Johnson from the Albuquerque, New Mexico office said, "That is what we need, we want you to analyze the Concho River Watersnake, we have a jeopardy case, Section 7 consultation with the Bureau of Reclamation, they want to build a dam on the Concho and Colorado Rivers in the middle of Texas," San Angelo, Texas, is off here on the map and so the proposal from the politicians of the corp was to put a dam about here to create a reservoir of about this size and the biologists were saying, "Well this is bad." Because here you have a snake species and imagine this is a river, the Colorado River and this is the Concho River. So you have a snake species that used to be in about 2,000 miles of habitat in all sorts of streams that went up here but due to all of these small dams and we had a rancher question here earlier, this is one of these cases where building teeny little dams interrupted the dispersal of this snake and this is a metapopulation snake so the interrupted dispersal fragmented the species and the species went from 2,000 kilometers down to about 500 kilometers in 1987 and now there was going to be a major dispersal barrier put in here to try to trisect the current population. The biologist said, "Fish and Wildlife should be in jeopardy and you should stop the building of the dam," so they hired Soulé and me to do a PVA of this thing, we had a month to do it. We had pretty good data including a bunch of videotape in a helicopter flying over these rivers looking at the habitat which immediately made me nauseous and took three days off of my time. But surveys were done, they had a lot of graduate students out here, they have done genetics, they divided the river up into these patches because these snakes only persists in ripple habitat, it does not like smooth flowing stretches of the river. These rivers are like the ones you have around here, they are dry for one-half the year, but when they are flowing in the late summer the snake can only feed on ripple habitat where the water is going over the rocks. The snake will perch on branches over the river and strike out a little fish from these branches because that is the only way they can feed. The size of these cells is proportional to the amount of good habitat in a five kilometer strip, 500 kilometers divided up into five kilometer stretches, there are 100 patches here.

This snapshot is the occupancy in black of those patches in 1987, they had a 1983 survey where different patches were occupied so there had been extinction recolonization events between 1983 and 1987 over a short period of time so this looked like a metapopulation. It also had zero genetic heterozygosity which is consistent with being a metapopulation, but I do not have time to make that argument.

Now, we are making something that is much more realistic, it actually fits the geometry of the landscape, it has the adjacency of patches. See, the colonization is basically only 61 or 62 patches, up or down stream. You do not have snakes swimming one-hundred miles, they just cannot make it, they get predated on as they go through the clear flowing areas. To go a mile, it is pretty good in a lot of ways it is as good as it can be at that time. I am going to tell you about one huge error, but we can run the model.

This is sort of the same thing, the patches are blinking this is 300 years into the future so the answer for this is that the current configuration of the snake is viable. It almost never goes extinct in the simulation runs. Sure, it has lost a lot of range but the species was not listed at this point in time, it was listed within one year of our work, another one to be listed. Currently the analysis would not underscore a support listing because the best model is not predicting extinction. It has never gone extinct in 300 years, but the issue is jeopardy.

We can add the dam. Adding the dam permanently extinguishes all of these patches or so we believed. So now you run it and it does worse. So this line is the number of extinct patches and typically what happens in these runs is all of this system will go extinct and all of this system will go extinct. After trisection you now have two unviable metapopulations but you still have one viable metapopulation. The answer out of this model is the jeopardy opinion is not warranted because again, you are going to get further reduction in range but if you are basing jeopardy on viability, the thing is not unviable. Well then Soulé and I did not like this answer but there it was. Soulé said, "Yeah, but what happens if there is an interstate highway, or what happens if an oil tanker drops off the interstate highway and sends a bunch of nasty pesticide down this river, there is no refugia and it will all go extinct so that is a catastrophe and the Army Corp of Engineers nodded and said, "Well we will hire some graduate students to move snakes." They did go ahead with the listing and there has been further work. I was just on the phone one month talking to some of the Fish and Wildlife people in the Albuquerque office and they want to do another PVA and they said that in fact, what we were told is that the reservoir would be bad habitat because the snakes would get predated on by bigger things. The graduate students working out here now are finding snakes all along the edge of the lake where the branches come over the lake and they are striking down. The dam could still cause problems getting over the edge of the dam but at least this connection is higher. Maybe this is going to be something where further information is going to lead to a change in the predictions of the model that the trisection is not as bad here in the dam per se and retrospectively was not as bad as it was first prospectively to be.

I am going to stop here, I did not mean to take as much time as I have so these are PVA's starting from the gambling intuition, leading to some toy models and coming up to a real world case that had real implications. I mean this particular case where a lot of people were not put out of work, but this kind of modeling had the input numbers been different it could have denied San Angelo their bass fishing lake. Thank you.

We are a little bit late but I can take a couple of questions.

Q:In a couple of instances you have pointed out the importance of sampling efficiency in predicting species persistence. In your models you have shown that you can have sampling efficiency going all the way up to one. In the real world the examples are going to be biological that indicate you cannot do this, what are some of the ceilings we can expect?

A:Oh, that is a good point. That is not my area of expertise because I am the guy that takes the data the field people gather. See, it always a question of time and money, I mean to thoroughly sample Yellowstone is a lot of time and money but then as you have point out, there is sometimes just impediments to perfect sampling. In your sampling here you are disturbing the population over there, you have to let it settle down before you can go over there. There is just a variety of things since it changes from species to species. Birds can be fairly easily sampled because sometimes you can go out on territorial calling. You have a tape recorder, you play this thing and the bird comes in and displays and then you can check off the presence of the bird. Other things are pretty cryptic and hard to find, I do not know at all about the Pygmy Owl. I mean the Sonoran Pronghorn would be probably be easy to sample.

Q:Coming from San Diego, maybe you can tell us how their regional habitat conservation plan models might fit.

A:Zero. Well now that is untrue, but around 1993 the political will changed from more from doing single species analysis to doing multi-species analysis so now you have to do 100 PVA's and you want the answer sooner. There are other techniques that are coming to be used instead of real thorough PVA's so PVA';s seem at a bit of a decline because of all the demands for data and things like that, but for particular umbrella species the PVA can be very important. The Desert Tortoise, the PVA was the thing that was underlying the research design. There are other considerations that come into play. You see, the PVA 's can be more or less good, but you are probably still going to do a PVA, it is just a matter of whether it ends up being graphical on a computer or being an opinion of an expert or something like that. PVA to me is a big umbrella term that simply means "Population By Ability," species analysis. It is like financial analysis where you can go in, someone can look at your stock and real estate holdings, nod and say, "That's good," or someone can charge you $10,000.00 and give a very detailed analysis of what stocks you own and so on. So, there is a lot of variation here. My bet is always to go with good mechanistic models.

Q:Can you develop techniques for using these models?

A:Excellent question. See I am not developing this but I am now more and more incorporated into technical teams that do this. Fifteen years ago they maybe hired someone like me and said, "Run with it." Now, there is always a technical team and there is a lot of feedback correction and there is also lots of cognizance from the experts that there is uncertainty about these things. The uncertainty has to be put into these models. Now I have mechanisms that I did not explain in this short talk. That is what the craps homework exercise are about so you should never just look at one of these computer graphics and see what it is feeding you. Change the assumptions a little bit, sometimes you find that changing this assumption does nothing but changing this assumption, this other one over here the answers are dramatically different. This then informs you that the most important data you are going to need pertains to this presumption and that is where you should spend your money, or that is where you should factor in the uncertainty. You should always have a very thorough understanding of the uncertainty of these models and that was one of the points of my talk, I was trying to get across that there are some limitations of these things. This is not physics, this is something much less than physics and see the public in particular should be aware of the limitations of these things. I hate it when some academic comes in and says, "This is the answer, everyone shut up." That does not work, I mean I used to do that but not anymore.

Q:In your study, have you also been involved in with the genetics?

A:Yes.

Q:For instance, have you got these animals spread out in small pods?

A:Very much so.

Q:We have heard several comments this morning where the speaker said something about the predicament of the Oregon loggers would be in a sense extinct if they protected the Spotted Owl. The affect on the loggers was not as they had predicted. I have a question here about ranching and conservation. Are similar kinds of models being done that would look at the impact on the environmental objectivity?

A:See, I am working on the team now. We have been meeting with people in Tucson for the last couple of decades. We are doing things that are rather distant from PVA. PVA presents a parameter and they are more of a landscape approach, very, very much like what Reed is doing. We are actually using a final computer optimization model to consider all the PVA land uses, the costs and things and then come up with a conservation landscape. We are doing it one species at a time, we are going to superimpose multiple species and try to get efficient solutions but the answer is the world is moving in this direction. My expertise still lies at the level of single species and that is a full time job sir, for several people.

Q:[inaudible]

A:You have read Limits to Growth I take it back in 1972. That is how I got into Conservation Biology, I was worried about the human species. There were these books written in the early 1970's called Limits to Growth and if you remember those things, they all went crash! They went crash because of nuclear war, because of overpopulation, accumulation, pollution, loss of Ag land and all sorts of things. I was pretty unhappy with managed future when I was twenty-five and living in 1972. Technology was the answer that everyone mentioned at those points, I was going to save everything. That's nonsense, but if you look at what is going on with technology and productivity in Ag land and things like that it looks like we are here to stay.

If you really want to get your homework in early, you can work on it tonight.

Michael Gilpin:If you didn't get enough of that, the website is posted here.

http://insci14.ucsd.edu/~bi178s/PVA/

Thank you.

APPLYING THE SCIENCE OF CONSERVATION PLANNING TO THE BIOLOGICAL ELEMENT OF THE SONORAN DESERT CONSERVATION PLAN: BILL SHAW

What I would like to do briefly now is tell you a little bit about what the Science and Technical Advisory Team has been doing in the last six months or so and hopefully talk a little bit about how we are attempting to incorporate some of these types of techniques and this type of knowledge into the situation that we have here in Pima County. So we can just begin with the slides.

As I think most of you know, one element of the Sonoran Desert Conservation Plan involves the biological aspects of it. The Science and Technical Advisory Team for the Sonoran Conservation Desert Plan is charged with overseeing this process and ensuring that we have appropriate integration of conservation into Tucson's Comprehensive Planning. As you all know, Tucson is a city that is blessed with a very unique environment, unique biota, still a fair amount of habitat that is still available and most of us are here because we appreciate the beauty and diversity of the plants and the animals that depend upon these plants.

It is also an area that has a thriving economy and a growing economy and so we are rapidly usurping this habitat for human uses. The question we are faced with is whether the Sonoran Desert Conservation Plan is, how can we take a comprehensive look at the entire Pima County region and direct this growth in a way that will ensure that in the future we will have some opportunities to enjoy the biota and beauty of the Sonoran Desert?

Now, most people here probably share some frustration with the rate at which growth is occurring in Tucson and the places that have been lost in recent years as a consequence of this growth, but it comes as a surprise to a lot of people that Tucson is actually viewed as one of the leaders in the interest to integrate conservation into development. If you go into the scientific literature, one of the first places you will see any reference to urban biological communities is a classic piece by a preeminent ornithologist Emlin who spent a sabbatical out in Tucson in the 1960's I believe it was and wrote an article dealing how different urban landscapes affect the types of birds that are able to exist.

We go way back long before many people, especially professional biologists who were not talking much about urban wildlife issues. I have kind of a strong history, although we have not necessarily impacted the pattern of growth as much as possible. Back in the mid-80's the identification of critical habitats more recently a series of studies in Saguaro Monument addressing the affects of urban growth on the wildlife of the monument. More recently than that, a systematic inventory of land covers within Tucson in which we actually looked at the types of vegetation associated with different zoning types that put us into a position of being able to answer some questions like, when we make decisions as a community, what will its effects be on the natural vegetation and the wildlife that are associated with it?

And we can go back and say, "On average for example, the major rivers of about 405 of the vegetation that is native vegetative cover and so on and we can do this for the various land cover types. We actually have a wealth of information as Sharon mentioned, we have even attracted people most recently. We had several hundred people from around the world participating in an Urban Wildlife Conference so it got lots of information, continuing studies but what we have not had is coordination of this. We had individual projects, development projects that have been impacted substantially but we still continue to grow in a piecemeal way without any comprehensive vision of how we want to grow as a community and what areas are most appropriate for development, what areas are most appropriate to meet some kind of objective of preserving biodiversity within the context of urban growth and development throughout Pima County.

We continue to have this lack of comprehensive vision, a kind of frustrated vision in which we desperately needed a symbol of wisdom, someone with wide open eyes but a hard nose to take the leadership and of course, that came in the form of the Cactus Ferruginous Pygmy Owl in March of 1997 which all of a sudden instead of being just local politics, this became more of a national issue because of course, Endangered Species address a national heritage, the concern of everyone for preservation of biodiversity. As a result of this, there has been the formation of this coalition that you are representing here and all the exciting things that are happening right now in relation to the Sonoran Desert Conservation Plan.

I would like to tell you a little bit about what the Science and Technical Advisory Team has been doing. We convened a group of nine scientists beginning last March and have been working with the help of Pima County staff in doing a lot of preparatory steps to put us in a position where we can begin to implement some of the science that you heard about today in the development of the biological element for the Sonoran Desert Conservation Plan.

We began by defining a mission, exactly what it is we hope to accomplish out of this which is to ensure the long term survivability of all of the indigenous species in the region. This is just some quick bullets on some of the things that we have accomplished so far. We began by talking to experts in individual groups of wildlife to get a list of which species are most vulnerable, which species are in some degree of jeopardy and in some cases, which species are the source of problems such as invasive exotic species. We have gone through several renditions of a report, a list of species of concern to make sure that out of this process we have at least on the table, a list of all the possible species that we ought to be concerned about as we go through this planning process.

It is a very dynamic list, we organized and reorganized it repeatedly with the help of Julia Fonseca and Pima County staff, we provided and developed a brief environmental history of the area with the hope that when we bring in some outside consultants to help us with this process we can get them right to work with a good understanding of this region without having to gather a whole lot of basic information so we have been trying to pull together a whole bunch of different types of information and get us in the position where we can write an intelligent scope of work that will lead to a contract for environmental consultants to come in and assist us with the natural development of the biological element for the Sonoran Desert Conservation Plan.

Three basic steps which I think as we go through this, you will see some parallels of the things we have heard earlier, particularly what Dr. Noss was describing. We did not pull together all the basic information that we need to identify which habitats are most important and then develop a biological element for the Sonoran Desert Conservation Plan.

What you will see up here is kind of a different but very similar organization of which we are trying to approach this from several different levels of analysis. It is not simply a matter of developing a plan for the Cactus Ferruginous Pygmy Owl, we want to develop a comprehensive plan for Pima County and provide biological input into that plan. In addition to the threat of endangered species that are in some ways have initiated this process because of the economic impact of these issues, we are going to make sure we look at other vulnerable species that are not today, threatened or endangered, so we can ensure that they never reach that status in species with special social significance and then at the community level, we want to simultaneously be looking at which biological communities are most important. And then come back and address the question of whether some socially significant species or species that may not be endangered or come up but are dependent on large areas and what can we do to make sure that whatever system we develop will provide the continued existence of areas of species that require large areas.

We are pulling together the information on various species, various communities such as Honeybee Canyon here that have special significance, virtually any riparian environmental course. The Sonoran Desert has very high importance, even within the Urban Design Departments. As I mentioned, the large area dependent species such as mountain lions or mule deer, we want to make sure that we address the metapopulation issues that Mike Gilpin just described in whatever pattern of habitats that we do leave as the plan is developed.

What always happens in this process is when you start asking questions: which species should we worry about? We could draw a curve of them, the more times you ask, the bigger the list gets, it goes on and on so one of the most challenging things we have to do is boil this list down because we simply do not have the resources or knowledge to address all of these species and we are still in that process and still have a long way to go. We have focused on species that were identified as being biologically vulnerable and that still leaves us with an unmanageable list, 74 is far too many. Our next steps would be to continue to see if we can narrow this down to a number of species that is more manageable. By focusing on key species that we know that if we provide a plan for conservation on these individual species, umbrella species or keystone species that it will also serve for protection for many, many other species that are vulnerable.

Pima County is a huge, huge area. We really cannot expect to go out and gather detailed information about the entire area so we are going to need to focus on key areas that we know are of special significance if we are going to accomplish our mission of preserving the biodiversity of this region.

Just to show you some of the conversations we have had, one of the big issues of Pima County is the impact of invasive species that are not native to this area on native species. We are not going to develop a conservation plan for these but we felt it was important to provide as a foundation, to list these species and discuss them a little bit and address their significance as well on any effort we have to restore and conserve species in Pima County.

Gradually as we begin to develop this information, our challenge will be to integrate the critical habitat information, with information about the protective status of lands, regional contacts and basic fees, etc. in order to produce the biological element for the Sonoran Desert Conservation Plan which again is one of the unique things I think about Tucson's effort. We are focusing on the big picture, the Sonoran Desert Conservation Plan. One aspect of that will be the possibility of Section 10 permits to address the native species issues. We want to keep our main focus on the big picture in how we can integrate conservation in Tucson as a community. Endangered species will be one aspect of that.

I think there are some very special opportunities at this particular time that we have not had in this community in the past. Those of you who have been around for awhile have seen many efforts to get some comprehensive planning that end up sitting on the shelf. We do have this Pygmy Owl situation that has become a very effective motivator and has created a strong coalition. The realization that we do need to address some sort of comprehensive planning for this community so we are not continually fighting on a case by case situation which is really in no one's interest.

We have extraordinary backing from the Interior Department which is going to help us do this as you probably heard. The Interior Department has identified Tucson as kind of an example, it hopes to see a good example for many communities in terms of how we address these issues. There are some new aspects of state law that may make acquisitions of some of the state trust land and issues like that more feasible. That plus the fact that we have a robust economy at this time, all of these things kind of come together and create a very special opportunity that we have not seen in the past 20 years, to do some meaningful planning.

We also have some real challenges. We have rapid growth and demand for this growth to continue, we have a huge area that we are trying to address. Someone pointed out to me yesterday the size of Pima County is the size if you take Rhode Island, add another Rhode Island, add Connecticut and add Vermont, that is about the size of the area we are planning for. It is a huge, huge area which again, points to the critical importance of our focusing our efforts on those aspects of conservation planning that are most important because there is no way we can do it all in an area like this.

We do have relative to many communities a lot of biological information but certainly not enough to achieve the comfortable limits that we would like and we have this tradition within Tucson of watering down and shelving any Comprehensive Planning effort before it ever amounts to too much. We have to overcome all of these issues but I think when you look around and you see the people that show up for meetings like this, the amount of effort that is going on in this community and public attention to this whole Sonoran Desert Conservation Plan.
I think we have an opportunity now that we have not had in the past 25 years to develop some comprehensive planning so that we can continue to enjoy the environmental amenities that make it so nice to live in Tucson which include not only the common species that we live with on a day to day basis but some of the rare species that most of us are not lucky enough to see but we still care about preserving and the vehicle we are using is the visionary proposal for the Sonoran Desert Conservation Plan. That is what the Science and Technical Advisory Team is attempting to do, we do have some additional time. If you have any questions for Dr. Noss or Dr. Gilpin or any of us, we would be more than happy to answer them.

QUESTIONS AND ANSWERS

Q:We have been sitting here for several months, learning a lot and you folks have been working but I am not sure I quite understand how the two processes are supposed to come together and what input we can expect.

A:This is a Maeveen question I think.

Maeveen Behan:I think the question was -- and I am not going to take a lot of time today because we will have that discussion in the near future -- the question was, at what point do the lines cross between the public process and the technical process? They cross at meetings like this where you are introduced to the work of the technical side and they will cross more directly after you graduate from boot camp and go in to a more refined kind of land panel format. Carolyn Campbell had a good suggestion that the Board might choose to implement which is to have people with expertise in certain topics that are on the steering committee be able to produce white papers and watch the whole process. And so we will move into sort of a land panel formation, and the technical people will be protected I guess from the politics, if that is your question. I think we have heard that from every corner of the public that they want to make sure that the science remains protected and so we do want to do that, and as much as we can, have the science team report out to you and give you information, educate you in a broad sense and then go to each land panel, to each community and give that information to as many people as possible as we go forward. That is, I guess, the general sense of where the lines cross. All the technical teams, science, cultural, historic, ranch and implementation will start working with consultants as soon as we get our planning money and so right now this is all free work from the expert committees, and they have done a really great job. Usually this what with most communities would call down time, waiting for what we hope is a federal appropriation for planning. During this time, our expert teams have generated a tremendous amount of information, and that effort shaves millions off the price and years off the time of conservation planning. You will hear more from the technical teams, more from the consultants they ultimately link up with -- this is a continuing education process. Ultimately your goal and your charge is to take the work of the experts and give advice to the elected officials about what type of preserve alternative you would like to see -- and you need to know a lot to do that.

Q:To what extent will the Science and Technology input shed light on specific local issues like wildcat developments?

A:I would like to think that we will provide the community with an ability to make more intelligent decisions or understand more intelligently what the impacts of that kind of public policy issue or subdivision can occur totally unregulated. I would hope that our information would strengthen public and policy controls. Those are the types of variables that are being plugged into the models that we taught about today, or among the variables.

Dr. Shaw:The question was, with the variables in Pima County how much of the land can be subdivided and developed without much regulation such as referred to as wildcat process?

Once the biological element has developed and goals in terms of species and communities occurs [inaudible] socioeconomic analysis of what goes on in the land so for example, we are fortunate by having large protected areas in the forest areas of the forest service in areas like this that are going to address many of our biodiversity issues already. We probably will not need a new preserve to reserve mixed comment for environments because most of those occur where there is considerable protective status already so that will help us focus things but what the community has to do, of course, is prioritize which areas are worthy of protection and to do that, they will need to know the some of the socioeconomic issues like which lands are subject to have unregulated growth which would make them [inaudible] so that is definitely part of the modeling that we are talking about doing as part of the process.

Q:While this process is developed, is the Science and Technical Advisory Committee looking at those issues?

A:Well, I think our strategy I guess is to get as high profile as we can to what we are doing on the science side, the issue of whether there will be more oriented periods of time when nothing much occurs is one that [inaudible] biology, we hope to find ammunition and assistance. I do not see as our task, that level of policy recognition.

One comment, when the gnatcatcher was listed in California that triggered a lot of this in Southern California, it was listed as threatened and the Fish and Wildlife Service anticipated what the problems might be and concomitant was the listing that they published some special rules that provided for this interim take. Unfortunately, the Pygmy Owl was listed as endangered and with endangered species, you do not have as much flexibility but my feeling is that the Fish and Wildlife Service understands the need for interim provisions and there might be a way to negotiate with them, but this is only speaking as an outsider.

Q:Dr. Noss, you mentioned corridors in passing, I wonder if you could elaborate on what experience have been in other places of wildlife corridors? What could that look like?

A:Wildlife corridors that have been studied most in urban environments and found to be effective are essentially ways to bypass barriers. There are underpasses on highways, they are in fact preparing some cover to dispersing moving animals. Wider overpasses across or underneath highways, providing riparian cover. [inaudible] they might be concerned with different types of habitats that species are vulnerable to isolation might require some contiguous form of corridor for their needs. I would emphasize that corridors have to be designed relative to the particular type of species [inaudible] subarea of your County. You cannot design a corridor automatically and expect that every species is going to be able to use it, you have to know something about the history of those organisms and what might actually serve as a barrier to them in order to get around.

Q:In reference to the food plan, if the food is not around for them and health is not maintained among the animals, the population is not going to be there. If we could provide better food for these animals, would we really be helping the animals and building the population so that we do not have some of these endangering issues? Has anybody looked at the food side of it? See what their diets are and if we could provide food for them, perhaps that could increase their population which would be better for everybody.

A:Its food, its cavities in the case of cavity nesting, it depends on what the limiting factor is but as a general rule of thumb, the best strategy of providing habitat requirements of individual indigenous species is to provide natural vegetation that has allowed those species evolve for millions and millions of years. That is the kind of foundation you need in your conservation plan, to provide the natural community plants that supplies the food covering all the other needs for a species. There are a few special cases when you manipulate environments to a high degree in order to pump up the population [inaudible] like the Pygmy Owl, the issue is almost certainly not a matter of limitation of food, it is solely a limitation of habitat availability.

Q:[question inaudible]

A:Only indirectly, in the sense that because we have converted their primary habitat with riparian corridors in areas in this region to other human uses, you take away the vegetation you destroy the habitat and not just food but all the other things. Food is not the issue with the Pygmy Owl.

Q:[question inaudible]

A:Well basically you have to go out and survey and this is one of these areas where genetic sampling can frequently indicate where there is low dispersal because over time, genetic differentiation will build up in these local populations whereas if it is not a metapopulation but only superficially appears to be patchy with lots of frequent movement between them, you will find genetic homogeneity. So the short answer is sometimes genetics which is a relatively rapid and inexpensive approach to doing the analysis. [first part inaudible] animals to see how they move over their lifetime but genetics [inaudible].

Q:[inaudible]

A:Well, remember it is in the species side. See, we cannot just look at a landscape and know what the species is going to do on it, we have to measure them over their lifetime which is a difficult thing but if you measure genetics and find that fairly close to the adjacent populations have substantial gene frequency differences, the assumption is that you do not have a lot of movement between these things and it is a presumption that it is a metapopulation.

Q:[inaudible]

A:The question was, in the past from other studies, how many other corridors work for the animals? Well this again, we have had relatively few studies of wildlife corridors and that is part of the problem but studies, for example, in Southern California by Dr. Paul Byer, he was hooked on the mountain lion and he found that certain culverts under a highway make a barrier to some species and certain culverts, they just would not go through. Some animals would not cross a narrow culvert but a wider underpass, whether it was a large area available with more cover, more vegetation available for the animal then they were more frequently used. A lot of it is consideration has to do with security, providing security to the animals.

Q:Do we have an opportunity in this situation that perhaps have some influence on the Endangered Species Act?

A:I guess the best answer to that is what we are doing here is what many, many communities are struggling with, it is learning to live with and utilize and make an effective Endangered Species Act for each of these give us a little bit of knowledge of how we might make that act work better in our society so it would be just one more piece in that direction.

Q:What is the relationship between our local Science Technical Advisory Team and the Fish and Wildlife Service ?

A:I would have to say it is somewhat intimate and from the beginning, Babbitt's Office assigned one individual here to work with us throughout it and at most of our meetings, we have had several people from the Fish and Wildlife Service local offices, they have been a resource for advice and consulting so from the very beginning they have been heavily involved and indeed, we have their one person from the Fish and Wildlife Service, Doug Duncan who is on our side on the Technical Advisory Team.

Q:What do you see from your role on the Science and Technical Committee as the major policy judgements that the steering committee will ultimately have to provide recommendations for the Board of Supervisors?

A:Well, I think our task is to provide this steering committee with vision of what we see as the most appropriate strategy for conservation, integrating conservation and all the other things that are being considered as part of this big comprehensive plan. I guess what I would anticipate is, like the way it is going to work, the biologist, we do like to gamble, we do like to win. We would like to make some recommendations that the whole world might not really be able to live with in our community. The steering committee has got to have representation from all interests and you are going to have to make recommendations and integrate them with science, ranching culture and concerns for all other issues that are part of this. My guess is that our recommendation is going to be very strong for biological concerns and your task is to make judgements on tradeoffs to make biological adjustments with other parts of the comprehensive planning.

Maeveen:One piece of information that might help -- if you look at the education series outline, I hope you will show up for one session in particular -- the all day education session at the university. We will work in smaller groups, and you will see an interweaving of each of these strands -- fiscal, cultural historic, ranching, conservation biology -- and you will see at that session, how do you draft a species conservation plan. The other overlay that you will receive at that time is what we have been working on this week with Mike Gilpin and three other scientists from the University of California. We are working to create a decision model that shows the tradeoffs involved in your decision to promote a certain preserve alternative. We will talk about that too in October. You have to preregister for that session.

Audience:November.

Maeveen:You are right, November 6th at the university and I really encourage you not to miss that session.

Q:[inaudible] have you done studies on other animals or birds to indicate their dominant within the urban area?

A:The answer to the last part is yes. And to the first part, I can assure you the coyotes will be back, populations are cyclic in coyote populations but they are naturally cyclic and you may not have seen any in your neighborhood for the last few years but go a few miles away and I think you will find different perspectives. There are plenty of coyotes. There are a whole bunch of species that have been studied. Javelina, mule deer, we have studies going on with roadrunners, bats, Desert Tortoise and lots and lots of individual pieces but as I said before, what we have lacked is being to pull all of these together in a comprehensive conservation plan.

Q:Is the Board going to be dealing with their own guidelines soon?

A:Chuck Huckelberry: Probably the answer will come from seeing what comes out of the recovery plans for the Pygmy Owl and my guess is that when we see the specifics in that recovery plan it will then be required to take before the Board, specific actions regarding an interim plan, but until we have those specifics there is not much we can do. We can do interim plans for every element, I think we can do an interim plan for ranch conservation, etc., we just have not gotten that far so I think the first interim type planning process will probably lead to discussions with regard to regulation or what we may need to do with land use will come from the recovery plan for the Pygmy Owl.

Dr. Shaw:Why don't we give a hand to the guests that came from out of town. Thank you.