On March 21, 1998, approximately 300 scientists and students gathered at the Milwaukee Public Museum for two days of scientific presentations and intense discussion on amphibian declines and malformities. Never before had so many persons come together to address amphibian conservation in the Midwestern United States (Minnesota, Wisconsin, Michigan, Illinois, Indiana, Ohio, Iowa, and Missouri)

Casper, Gary S.

English

University of Northern Iowa

The Journal of the Iowa Academy of Science: JIASVolume 107 | Number 3-4 Article 42000Introduction: A Perspective on MidwestAmphibian DeclinesGary S. CasperMilwaukee Public MuseumCopyright © Copyright 2000 by the Iowa Academy of Science, Inc.Follow this and additional works at: http://scholarworks.uni.edu/jiasPart of the Anthropology Commons, Life Sciences Commons, Physical Sciences andMathematics Commons, and the Science and Mathematics Education CommonsThis General Interest Article is brought to you for free and open access by UNI ScholarWorks. It has been accepted for inclusion in The Journal of theIowa Academy of Science: JIAS by an authorized editor of UNI ScholarWorks. For more information, please contact scholarworks@uni.edu.Recommended CitationCasper, Gary S. (2000) "Introduction: A Perspective on Midwest Amphibian Declines," The Journal of the Iowa Academy of Science:JIAS: Vol. 107: No. 3-4 , Article 4.Available at: http://scholarworks.uni.edu/jias/vol107/iss3/4Jour. Iowa Acad. Sci. 107(3):59--60, 2000 Introduction: A Perspective on Midwest Amphibian Declines GARY S. CASPER Associate Coordinator, United States Declining Amphibian Populations Task Force, Milwaukee Public Museum, 800 West Wells Street, Milwaukee, Wisconsin 53233, USA. Email: gsc@mpm.edu On March 21, 1998, approximately 300 scientists and students gathered at the Milwaukee Public Museum for two days of scientific presentations and intense discussion on amphibian declines and mal-formities. Never before had so many persons come together to ad-dress amphibian conservation in the Midwestern United States (Min-nesota, Wisconsin, Michigan, Illinois, Indiana, Ohio, Iowa, and Mis-souri). Amphibians have had a long history in the Midwest, and the modern species assemblage dates back 10-18,000 years ago, when much of the region was buried under massive sheets of ice. The very crust of the earth is, to this day, rebounding from the compression caused by the weight of these ice sheets. As the glaciers receded, the region underwent drastic ecological change. Climatic warming, ris-ing carbon dioxide levels, and melting glaciers (with the formation of many meltwater lakes and rivers) made for a very different envi-ronment and climate than we see today. Winds blowing off the gla-ciers are thought to have kept adjacent regions constantly misted and cool, factors that favor most temperate amphibians. Over hun-dreds of years, lands liberated from the ice underwent changes from tundra-like conditions, to spruce forests, to mixed conifer-hardwood forests. Some regions then became grassland or savanna, other regions remained forested. During this period of successive ecological change, amphibians marched steadily northward with the receding ice front. Periods of glacial advance and retreat, coupled with climate fluctuations, often isolated or divided populations, and new species evolved (witness the Ambystoma laterale-jeffersonianum complex). As climate change continued, some species once widespread in cool, moist, glacier-influenced forests, became isolated in pockets of moist-er habitat, resulting in scattered populations of "glacial relics" (i.e. Hemidactylium scutatum). Then European settlement began. About a century ago almost all forests were rapidly clearcut, then burned. Over the next few decades, most savanna and prairie regions were converted to agriculture, and 50-90% of wetlands were drained (with considerable geographic var-iation in losses). The impact on amphibians must have been pro-found. Perhaps entire species were lost. Soil moisture, soil pH, cover object availability, and light intensity all significantly affect sala-mander distribution (Wyman 1988a; Wyman 1988b, Frisbie and Wyman 1992, Sugalski and Claussen 1997, Grover 1998). Studies suggest that salamander populations may require 30 to 60 years to recover from clearcutting (Pough et al. 1987, deMaynadier and Hunter 1995). Since this initial abuse, second-growth forests have returned, but few wetlands have been effectively restored, and agri-culture has intensified. After a brief period of environmental concern in the 1970s, recent political trends have been to reverse and weaken environmental protection overall; as rapid development and road building continues unabated, giant corporate agribusinesses replace family farms, and hundreds of synthetic chemicals now permeate air, water, and soil throughout the region. Recent trends in forestry (con-tinued clearcutting and short stand rotation), and aquaculture (con-version of wetlands to fish farms and winter drawdowns), have also been harsh on amphibians. A recent research emphasis on landscape analyses and meta-population dynamics (see Ball, Knutson et al., this proceedings) has revealed the problems many amphibians face as landscape fragmentation proceeds, the most significant being isola-tion of small populations, which may not remain viable. This prob-lem will be compounded as global warming proceeds, and amphib-ians are unable to migrate across barriers, losing migration corridors. Midwest amphibian declines were first noted in the 1960s, when the Blanchard's cricket frog (Acris crepitans blanchardi) began to dis-appear from the north. In the 1970s, northern leopard frog (Rana pipiens) populations crashed. Currently, approximately 16 amphibian species are listed as threatened or endangered in the Midwest region, mostly because of habitat losses. In the mid-1980s Wisconsin began the nation's first frog and toad survey, and research into amphibian conservation began to increase. Then in 1995, Minnesota school children discovered grossly mal-formed frogs. Pictures of these monstrous anurans captured the pub-lic eye, and sparked a rapid media, political, and research response. An excellent summary of this investigation (still ongoing) can be had in William Souder's recent book A Plague of Frogs: The Ho"ifying True Story (Hyperion Press, 2000), and several papers herein continue the saga. Largely lacking in this debate has been an acknowledgment that malformed wildlife in the Midwest is nothing new, with syn-thetic chemicals implicated for past outbreaks of bird and fish mal-formities, and fish contamination and cancer rates remaining unac-ceptably high. As of this writing, the causative agent in Midwestern frog malformities has not been determined. However, at least three things have now been shown to be capable of causing these mal-formities: chemical contaminants, parasite infestations, and UV-B light. Interplay of these and other factors is also suspected in both malformity and decline issues (see Britson and Threlkeld, Jofre et al., this proceedings). The Midwest Declining Amphibians Conference was a joint meet-ing of the Great Lakes and Central Division Working Groups, of the United States Declining Amphibian Populations Task Force, which organizations are chaired by myself, Christopher A. Phillips, and Michael ]. Lannoo, respectively. While the focus of the conference was on Midwestern amphibian decline issues, interest grew beyond this geographic constraint, with attendees coming from as far away as Maryland, California and Guatemala. The conference became somewhat dominated by the malformed frog issue, then a hot topic in the press, but still considered a minor issue in amphibian decline by most scientists. Consequently, the new research being presented by scientists investigating potential causes of frog malformities at-tracted national attention, resulting in coverage by NBC Nightly 60 JOUR. IOWA ACAD. SCI. 107(2000) News (Chicago), ABC (New York), Wisconsin Public Radio (WUWM), Outdoor Wisconsin, Minnesota Public Radio, the Min-neapolis Star Tribune, the Milwaukee Journal Sentinel, and the Washington Post (among others). Participating agencies included seven state Natural Resources Departments, the United States En-vironmental Protection Agency, the Minnesota Pollution Control Agency, the Illinois Natural History Survey, the U.S. Geological Sur-vey, many universities and colleges, the Nature Conservancy, the National Wildlife Health Center, the United States Fish and Wildlife Service, the Pacific Northwest National Laboratory, the Patuxent Wildlife Research Center, the National Institute of Environmental Health Sciences, and the Northern Prairie Wildlife Research Center. This proceedings was conceived shortly after the conference, as a means of uniting papers on a common theme into one publication. The manuscripts were prepared and finalized in 1998 and 1999. Some authors could not meet publication deadlines, and others chose to publish elsewhere. Of the 45 papers presented at the conference, 25 are published here. They fall into two general areas: malformity investigations, and decline and natural history investigations. The content and length of papers is variable, with some contributions being extended abstracts. However, an important body of work is collected here, well representing the spirit of the conference. There remains much work to be done if we wish to reverse amphibian declines in the Midwest. Continuing natural history and monitoring studies are paramount to this goal. Basic distribution, habitat, de-mographic, and reproductive data are still lacking for many species (Redmer, Mauger et al., this proceedings). However, the major rea-sons for amphibian declines are well known (habitat loss and deg-radation). They are simply not being effectively addressed in the political arena. Relatively minor changes in forestry, fishery, agricul-tural, and development practices could have large impacts on re-versing amphibian declines (see Merovich and Howard, Mierzwa, Nyberg and Lerner, this proceedings). Reaching these communities is challenging, however, and the development of effective manage-ment practices and communication and implementation of these strategies remains the most important issue in amphibian conserva-tion in the Midwest (and perhaps everywhere). It is important that such strategies be based on sound science, towards which I believe this proceedings contributes. Abstracts from the conference are available online at www.mpm.edu/collect/vertzo/herp/Daptf/MWabst.html. Papers pre-sented at the conference, but not included here, were: Effects of methoprene and UV light on survival and development of Rana pipiens (G.T. Ankley, J.E. Tietge, D.L. Defoe, K.M. Jensen, G.W. Holcombe, E.J. Durhan, S.A. Diamond, and P.K. Schoff); Field and laboratory evidence for the role of retinoids in producing frog mal-formities (B. Blumberg, D.M. Gardiner, D. Hoppe and R.M. Evans); Iowa's declining amphibians (J.L. Christiansen and C. Van Gorp); Examination of a long-term monitoring technique and the effects of fire management on the herpetofauna of Chilton Creek Preserve, Shannon and Carter counties, Missouri (B.M. Churchwell and K.S. Mierzwa); Deformed frogs: developmental and molecular mecha-nisms (D.M. Gardiner and D. Hoppe); Wisconsin's amphibian mal-formations: 1960-1997 (H. Gilbertson, R. DuBois and R. Hay); The North American Amphibian Monitoring Program (J. Griffin); Blan-chard's cricket frog (Acris crepitans blanchardi) in Wisconsin: A van-ishing species (R. Hay); A methodology to assess exposure to organ-ophosphate insecticides in amphibian species (R. Hirsch and S. Tem-ple); Exposure of northern leopard frogs in the Green Bay ecosystem to polychlorinated hydrocarbons as measured by direct chemistry and hepatic P450 activity (Y. Huang, W.H. Karasov, K.A. Patnode and C.R. Jefcoate); Amphibian malformities in Missouri (T.R. Johnson); Ephemeral Pools in Missouri: Their Value, Status, and Restoration (T.R. Johnson); Predicting amphibian occurrence using landscape-level attributes (M.B. Kolozsvary and R. K Swihart); Recent surveys of Blanchard's cricket frogs (Acris crepitans blanchardi) in southern Michigan (Y.M. Lee); Minnesota frog and toad survey: changes and status (J.J. Moriarty); The Wisconsin Frog and Toad Survey: update and 1984-97 trends (M.J. Mossman, L. Hartman,]. Sauer, R. Hay, and B. Dhuey); Differential distribution of terrestrial salamanders in southern Indiana forests (N. Murphy); Gonadal intersex in cricket frogs (Acris crepitans): a retrospective study before, during, and after the era of organochlorine insecticide use (A.L. Reeder, A. Pessier, L. Brown, R. Warner, M.B. Wheeler, and V.R. Beasley); Forest succes-sion and the distributional dynamics of an amphibian assemblage (D.K. Skelly, E.E. Werner, and S.A. Cortwright); and Photo-en-hanced toxicity of a carbamate insecticide on early life stage am-phibians (A. Zaga, E.E. Little, C.F. Rabeni and M.R. Ellersieck). ACKNOWLEDGMENTS I wish to thank the conference organizers for their hard work, the Iowa Academy of Sciences for their role as publisher, and the Zoo-logical Society of Milwaukee County and the Milwaukee Public Mu-seum for funding contributions. The difficulties of meeting deadlines with so many authors (and a change of publisher late in the process) were profound, and I thank the authors and my co-editors for their patience and commitment to this project. LITERATURE CITED deMAYNADIER, P.G. and M.L. HUNTER, JR. 1995. The relationship between forest management and amphibian ecology: a review of the North American literature. Environmental Review 3:230-261. FRISBIE, M.P. and R.L. WYMAN. 1992. The effect of soil chemistry on sodium balance in the red-backed salamander: a comparison of two forest types. Journal of Herpetology 26(4):434-442. GROVER, M.C. 1998. Influence of cover and moisture on abundance of the terrestrial salamanders Plethodon cinereus and Plethodon glutinosus. Journal of Herpetology 32(4):489-497. POUGH, H.F., E.M. SMITH, D.H. RHODES and A. COLLAZO. 1987. The abundance of salamanders in forest stands with different histories of disturbance. Forest Ecology and Management 20: 1-9. SUGALSKI, M.T. and D.L. CLAUSSEN. 1997. Preference for soil moisture, soil pH, and light intensity by the salamander, Plethodon cinereus. Jour-nal of Herpetology 31(2):245-250. WYMAN, R.L. l 988a. Soil acidity and moisture and the distribution of amphibians in five forests of southcentral New York. Copeia 1988(2): 394-399. WYMAN, R.L. l 988b. Salamanders, soil acidification and forest ecology. Newsletter of the Edmund Niles Huyck Preserve, Inc. Winter 1987-1988. Rensselaerville, New York. 

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