Paleozoology in the Service of Conservation Biology
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Evolutionary Anthropology 15:11–19 (2006) ARTICLES Paleozoology in the Service of Conservation Biology R. LEE LYMAN Paleozoological data reveal past conditions created by anthropogenic and nat- grapple with the fact that ecosystems ural processes. These conditions can serve as benchmarks of ecological proper- and landscapes are not static for natu- ties and processes desired by conservation biologists. Paleozoological data pro- ral and anthropogenic reasons.16 Their vide empirical evidence analogous to experimental results of anthropogenic and desire to manage a minimally anthro- environmental causes. They can be used to determine whether a taxon is native or pogenically influenced ecosystem intro- exotic to an area, distinguish invasive from recolonizing taxa, choose a manage- duces the difficulty of identifying the ment action likely to produce a desired result, test benchmarks based on historic boundary between natural and unnatu- data, reveal unanticipated effects of conservation efforts, and identify causes of ral.17–19 But nonanthropogenically in- ecological conditions. It is time to use paleoecological knowledge in the service of fluenced ecosystems are not always modern conservation biology. desired. For example, some anthropo- genically introduced exotic taxa such as game birds in the western United States Conservation biologists, restoration compositions of biological communi- are economically beneficial and ecolog- ecologists, and wildlife managers of- ties occupying tens to hundreds of ically benign. ten select an ecological benchmark,1,2 hectares, as well as to ecosystems con- The paleozoological record pro- ecological baseline,3 or historical sisting of organisms, geology, fire re- vides unprecedented data that reflect landscape4,5 that they seek to recreate gimes, and so on, as well as ecological the long-term operation of many eco- or maintain in an area. A benchmark and evolutionary processes.6–8 Typi- logical and anthropogenic processes is a goal toward which conservation cally, a benchmark is established by and may provide guidance to distin- activities are aimed; it is an ecological reference to the early historic period guishing effects of the two.20–23 My condition or process that is desired. because written records are available specific goal here is to show that pa- Benchmarks vary in scale from a par- and also because anthropogenic, par- leozoological data are a significant ticular gene pool or range of pheno- ticularly industrial-era influences, are source of information on bench- types to the presence or absence of a usually undesirable. Conservation bi- marks. I focus on mammals, but any species in an area of a few hectares to ologists realize that any chosen taxon of plant or animal can provide benchmark is a moving target given data concerning a benchmark. My the vagaries of both particularistic general goal is to encourage paleo- contingencies and evolutionary histo- ecologists to consider how their re- ries.9 They worry about long-term cli- search might be of value to conserva- R. Lee Lyman became interested in the matic change and anthropogenic vari- tionists and to publish their research utility of paleozoological data to conser- vation biology in the middle 1980s, when ables and their influence on plant and in journals such as Biological Conser- he was studying the morphometry of the animal taxa and ecosystems.10,11 vation, Conservation Biology, Bio- prehistoric sea otter (Enhydra lutris)inthe Conservation biologists find multidis- Science, Ecological Restoration, and eastern Pacific Ocean. That interest ex- panded with his examination, in the late ciplinary research necessary to contend Environmental Management to inform 1980s, of the controversy regarding the with ecological, biological, and land- conservation biologists of the value of exotic or native status of mountain goats 12–14 (Oreamnos americanus) in Olympic Na- scape degradation. The Long Term paleoecological data. tional Park. Together with Ken Cannon, Ecological Research (LTER) Network Paleoecologists publish in these Lyman recently edited the volume Zooar- established by the United States Na- venues, but they seldom identify the chaeology and Conservation Biology. tional Science Foundation monitors, exact management implications of over long periods, how and why ecosys- their observations.24–30 Perhaps this is Key words: ecosystems, conservation biology, tems and ecological variables and pro- because they believe it would be “dan- paleoecology, paleozoology cesses interact and operate.15 LTER gerous” to offer suggestions outside recognizes that research must exceed a their field of expertise.31 I believe, © 2006 Wiley-Liss, Inc. season or two, a year or two, or a even however, that we must make explicit DOI 10.1002/evan.20083 Published online in Wiley InterScience decade or two if we are to understand suggestions because conservationists (www.interscience.wiley.com). ecosystems. Conservation biologists do not always perceive the value of 12 Lyman ARTICLES an ecological benchmark is a moving target. EXOTIC TAXA AND NATIVE TAXA One conservation activity is to translocate animals from one popula- tion to another to regulate the size of the donor population to enhance or reestablish another population, or both. Translocation requires that we know the benchmark of local indige- nous taxa.42 Paleozoological data as- Figure 1. A model of how the environmental tolerances of a species influence its abun- sist with the determination of whether dance on the landscape. Any environmental variable such as number of frost-free days, annual precipitation, or temperature range can be plotted on the x axis. a taxon is native or exotic to a loca- tion. Definitions of exotic taxa vary.43 For purposes of this paper, exotic, alien, nonindigenous taxa are those paleoecological data. As more papers such terms as natural, native, pristine, that did not previously exist in an with such suggestions are published, and the like be explicitly defined. In area.44 Efforts in many national parks members of the conservation profes- the United States, the terms usually are devoted to eradicating established sions will realize that the long-term are defined as “pre-Columbian or im- exotic taxa and ensuring that no new 37,38 data provided by paleoecology is wor- mediately post-Columbian.” It is exotic taxa become established.45–47 thy of serious consideration. Then re- often implied that “Columbian era” Plans to reintroduce the North search as well as job opportunities for signifies nonanthropogenic, which ig- American wapiti (Cervus elaphus)to paleoecologists may increase and a nores the 12,000-plus years that the state of Missouri have been dis- new vault of funding may open. American Indians have been in North cussed for two decades. The historic Conservation biologists often mud- America and presumes that Native record indicates that this large ungu- dle along with imperfect knowledge, Americans had minimal influence on late was present in the state in the not knowing the exact consequences pre-Columbian ecosystems. Paleoeco- nineteenth century, but does not indi- 32 of their activities. To not act because logical data indicate that people cate all locations where wapiti were of imperfect knowledge represents the throughout the world had all sorts of found and not found. The paleozoo- 33 “paralysis of analysis.” Not only do ecological influences.39 Terms that logical record indicates that wapiti paleoecological data represent knowl- imply nonanthropogenically influ- were only present in the state when edge, they underscore the moving-tar- enced ecosystems and landscapes climates were cooler than at present get nature of benchmarks, and high- should be avoided.34 and that they occupied the topograph- light the fact that ecological stasis is The second point is that every taxon ically rugged and timbered Ozark Pla- unattainable. They also may suggest has been and continues to be shaped teau of the south-central portion of which of several benchmarks is the by natural selection to live within a the state.48 The state Fish and Wildlife most feasible to attain or maintain. A certain range of temperature and pre- Department plans to release wapiti in chosen benchmark will depend on so- cipitation, vegetation, geology and to- areas with open forest and prairie cial, political, economic, and ecologi- pography, predation, and other envi- habitats and little topographic relief. 34 cal variables. To convince anyone of ronmental variables (Fig. 1). If one of The transplant effort has been de- the “applied” value of paleoecological those variables changes, the taxon layed, but if the state plan is followed data, examples must be identified. has three options: to become locally will the wapiti survive where there is Here I describe several examples in extirpated, migrate to an area where no evidence that they are native? which paleozoological data have been the environmental variable has not Banff National Park straddles the brought to bear on particular conser- changed, or adapt to the new environ- crest of Canada’s Rocky Mountains. vation, management, and restoration ment.40 The third alternative can take Biologists are contemplating releas- issues. Before doing that, however, I at least two forms that are not neces- ing bison (Bison bison) into this rug- must address two background issues. sarily exclusive. The organism can ged wilderness area. Zooarcheological adapt by decreasing in abundance, al- data indicate that bison were present tering its morphometry, or a combi- there during the last 10,000 years and BACKGROUND nation of the two.41 A species may dis- that individuals were adult males; no Many federal agencies such as the appear from an area and reappear at a cow-calf herds are represented.49 United States National Park Service later date; its abundance may increase There is no evidence of differential are charged with managing “natural” or decrease only to decrease or in- preservation of male remains, so or “pristine” landscapes and bio- crease at a later date; or individuals should bison in the park be managed tas.35,36 This charge demands that may shrink or grow larger.