Amphibian Decline and Conservation in Central America
Central America hosts a diverse, unique, and imperiled amphibian fauna, and for decades Central America been a major epicenter of research into amphibian decline and conservation. In this critical and quantitative review, we synthesize current knowledge regarding amphibian decline and conservation in the seven countries that constitute Central America. There are 495 currently recognized amphibian species known from the region, distributed among the three extant orders, 16 families, and 69 genera—though description of new species continues to occur at a rapid pace. Central America's amphibian fauna is unique: 251 species are restricted to the region, and amphibian diversity varies among the major biogeographic provinces and climatic zones found in Central America. We use data generated by the International Union for the Conservation of Nature (IUCN) to evaluate trends in extinction risk among Central American amphibians. As of 2014, there are 207 amphibian species considered threatened by the IUCN, and threat status varies according to taxonomic groupings, biogeographical association, elevation, and life history variables. Major threats to Central American amphibians include both conventional threats (habitat modification, habitat fragmentation, overharvesting, and invasive species) as well as emerging threats that operate on large spatial scales (pollution, emerging infectious diseases, UV-B radiation, and climate change). We conducted a quantitative literature review to document conservation research and to show trends in research activity. While the number of published studies on amphibian conservation increases each year, there are pronounced biogeographic biases in the distribution of published research, and most research is conducted by scientists at institutions outside of Central America with limited involvement of host-nation biologists in amphibian research. We synthesize empirical studies of conservation impacts to amphibians in Central America from habitat modification and fragmentation, overharvesting, invasive species, pollution, UV-B radiation, chytridiomycosis and other amphibian pathogens, climate change, and synergistic interactions among these threats. Much research in the past decade has focused on chytridiomycosis and the amphibian chytrid fungus (Batrachochytrium dendrobatidis), with far fewer studies on habitat modification, other amphibian pathogens, or climate change impacts to amphibians. We describe ongoing conservation actions for amphibians in the region, including monitoring, protected areas, captive assurance programs, protection of relict populations, reintroductions, and development of in-country capacity for research and conservation programs. We conclude with a list of priorities in research and conservation action for amphibians in the region.
Political entities and physiographic provinces of Central America.
Amphibian species richness patterns of amphibians in Central America. Greatest species richness occurs in mid-elevation forests of lower Central America.
Elevational distributions and threat status of Central American amphibians. The greatest proportion of threatened species occurs at high-elevation sites.
Threat status (number of species listed as Critically Endangered, Endangered, or Vulnerable by the IUCN) of Central American amphibians. Data are derived from the Global Amphibian Assessment. Numbers identifying decline locations are as listed in Table 5.
Threat status is highly correlated with range size for amphibians in Central America.
Life history characteristics and threat status of Central American amphibians. Species that associate with more than one habitat may be included in more than one category
Trends in amphibian research in Central America. In both figures, gray bars indicated all studies, and the subset of each bar in black indicates the number of studies containing at least one author at an affiliation from the country of origin. A) includes all studies of amphibian biology in Central America; and B) includes only studies with direct conservation application. The vast majority of work conducted in Central America–for amphibians as a whole and for conservation studies in particular–has occurred in Costa Rica and Panama. A small proportion of research in Central America is conducted by in-country researchers.
Research activity in conservation by study topic. Studies may belong to more than one category.
Specific threats to the amphibians of Central America from IUCN data. Habitat loss threatens the greatest proportion of species, but species threatened by global warming, pathogens, or natural disasters are most likely to be at risk of extinction.
Recent trends in loss of forest cover, 1990-2010. Data in this figure are derived from FAO (2010).
Contributor Notes
Associate Editor: C. Beachy.