Vanishing Amphibians: From The National Museum of Natural History October 25 to December 7, 2003 Lora Robins Gallery of Design from Nature, University of Richmond Museums Vanishing Amphibians, an exhibition that addresses amphibians’ biological mysteries and the reasons for their recent disappearances, will be on view at the Lora Robins Gallery of Design from Nature, University of Richmond Museums, from October 25 to December 7, 2003. The exhibition, organized by the Smithsonian’s National Museum of Natural History and the Smithsonian Institution Traveling Exhibition Service (SITES), examines amphibian biology, worldwide declines of amphibian populations, and the international effort to better understand the extent and causes of these losses.
In the mid-1980s, scientists identified nearly a dozen populations of amphibian species that were in serious decline or had disappeared altogether. As Vanishing Amphibians explains, reasons for these disappearances have ranged from habitat loss, to contamination of breeding sites by agricultural chemicals, to the thinning of the ozone layer. Intriguingly, while one amphibian species may dwindle to the point of extinction, another living in the same environment might retain a viable population. Because of amphibians’ unique physiology, life cycle, and behavior patterns, individual species may respond differently to changes in the environment. This fact makes amphibians excellent barometers of an ecosystem’s health and stresses. Dozens of species of frogs, salamanders, and caecilians (little-known legless amphibians) have already succumbed or are at risk of extinction due to environmental changes worldwide. Vanishing Amphibians highlights case studies like that of Costa Rica’s Golden Toad (Bufo periglenes). Under normal circumstances, the Golden Toad would spend its time hidden below ground in the Costa Rica cloud forest, and then, during breeding season, hundreds of brilliant orange males would emerge to woo dappled females at temporary pools. In 1989, however, a single surviving male searched for a mate — and found none. Biologists now suspect that a combination of extremely low rainfall and pesticides carried by the wind may have caused the toad’s demise. The exhibition notes that even pristine areas such as Yosemite National Park are experiencing falling amphibian populations. Scientists found that three species previously common to the region had completely disappeared. In the absence of obvious problems such as habitat destruction or pollution, scientists have begun examining the possibilities of more subtle threats such as acid rain, climatic shifts, and increased levels of ultraviolet light due to the depletion of the ozone layer. Amphibian species are more vulnerable now than at any other point in their history. As a result, their plight has generated unprecedented levels of scientific research. The Internet and the Declining Amphibian Populations Task Force (DAPTF) of the World Conservation Union have become important vehicles for more than 1,200 scientists and volunteers in over 90 countries to monitor their local species and share their findings quickly with colleagues around the world. “While anecdotal evidence was sufficient to raise concern about the loss of amphibian populations, it was clear from the outset that a systematic and coordinated effort to assess the status of amphibian populations worldwide was necessary,” states Dr. W. Ronald Heyer, Curator of Amphibians and Reptiles, National Museum of Natural History. “Such baseline data are absolutely critical to identifying the causes of population declines.” As curator of Vanishing Amphibians, Heyer communicates key themes through the exhibition’s maps, vibrant photographs, and graphics. A lifelike model of Eleutherodactylus karlschmidti (Web-footed coqui) is accompanied by its call in the first of the exhibition’s two audio components. The second component features the individual calls of three common North American frogs, and then a chorus of the three frogs. By listening to and identifying the frogs by their calls, visitors gain insight into one technique scientists use to assess frog populations. Some exhibition components help visitors to learn about the physiology of amphibians, explore the threats to these delicate creatures, examine the effects of amphibian disappearances on local environments, and discuss what scientists and others are doing to address the problem. Engaging case studies illustrate how the unique characteristics that make amphibians so fascinating also make them vulnerable to changes in their surroundings — the very feature that puts amphibians at the center of today’s environmental discourse.