Puerto Rican Crested Toad Species Survival Plan
To breed and reintroduce Puerto Rican crested toads into their former range in Puerto Rico
The Puerto Rican crested toad, Bufo (Peltophryne) lemur, was formerly common on Puerto Rico and Virgin Gorda. The major causes for the toad decline include the introduction of species such as the marine toad, mongoose and rats, as well as habitat loss. The species is listed as Threatened by the United States Fish and Wildlife Service (USFWS). In 2004, the International Union for the Conservation of Nature and Natural Resources (IUCN) classified the Puerto Rican crested toad as Critically Endangered because
- of a population decline in the past ten years estimated to be over 80% as recorded from direct observation;
- its extent of occurrence is less than 100 km²;
- its area of occupancy is less than 10 km²;
- its population size is estimated to be less than 250 mature individuals;
- there is continuing decline in the number of mature individuals; and
- all individuals are in a single subpopulation.
The crested toad is the only toad native to Puerto Rico and it occurs in semi-arid to arid habitats where it lives in karst limestone formations. The toad population once existed as two distinct populations; one in the north and the other in the south. Significant differences in the mitochondrial DNA suggests that the two populations have been separated for over 1 million years. Unfortunately, the northern toads have not been seen in the wild since 1988 and are considered extinct. The only known wild population is the southern form, which occurs in Guanica National Forest.
A Species Survival Plan (SSP) for the Puerto Rican crested toad was developed by the American Zoo and Aquarium Association (AZA) in 1984. A major component of the program is reintroduction. Approximately 1,300 toadlets were released in Cambalache National Forest, in northern Puerto Rico, between 1982 and 1985. Between 1987 and 2005 more than 90,000 southern tadpoles were released in Guanica National Forest. Over the last 18 years tadpoles have been released rather than toadlets because it is believed that the tadpoles imprint on their natal pond habitat. Breeding is coordinated between 20+ zoos to occur within the same time period. Tadpoles are then collectively shipped to Puerto Rico for release. The release site at Guanica is a man-made pond that is geographically isolated from the wild population. For the first time since the reintroduction efforts began, ex situ bred tadpoles returned as adults in 2003 and 2005 to lay eggs. SSP members have helped construct several small ponds as new release sites. In addition, two large ponds (4,000 and 10,000 square feet) were constructed in historical toad habitat. These large wetlands will hopefully house satellite populations of toads in the future.
In addition to the reintroduction efforts, a high priority for the SSP has been the establishment of island-wide public education and outreach programs. A diversity of educational materials have been produced and distributed in Puerto Rico including: posters, bumper stickers, decals, activity books, life-size models of the toad, natural history booklets, and interpretive signs for the pond at Guanica National Forest. The Juan Rivero Zoo and Guanica National Forest now use a large costume character of the crested toad in outreach education programs. An exhibit, featuring zoo-raised toads, was constructed at the Juan Rivero Zoo in an effort to reach a larger audience. Biologists from the Juan Rivero Zoo were hosted by several AZA institutions for husbandry training prior to receiving toads. Additional capacity building activities by the SSP have included helping to remodel and produce new interpretives for the Juan Rivero Zoo Serpentarium and the organization/implementation of husbandry and nutrition workshops for Juan Rivero Zoo staff.
WAZA Conservation Project 06002 is implemented by The Audubon Zoo, Maryland Zoo in Baltimore, Buffalo Zoological Gardens, Central Florida Zoological Park, Central Park Zoo, Chester Zoo , Cincinnati Zoo and Botanical Garden, Cleveland Metroparks Zoo, Columbus Zoo , Dallas Zoo, Detroit Zoo, Disney's Animal Kingdom, Fort Worth Zoo, Granby Zoo, Juan Rivero Zoo, Louisville Zoological Gardens, Lowry Park Zoo, Miami MetroZoo, Milwaukee County Zoological Gardens, North Carolina Zoo, Oklahoma City Zoo, Omaha's Henry Doorly Zoo, Saint Louis Zoo, Santa Barbara Zoological Gardens, Sedgwick County Zoo, Toledo Zoo, Toronto Zoo and The Vancouver Aquarium Marine Science Center, in cooperation with Puerto Rican Department of Natural Resources, The United States Fish and Wildlife Service, University of Puerto Rico, Ciudadanos del Karso, and Inciativa Herpetologica, Inc. The SSP is supported by the American Zoo and Aquarium Association (AZA).
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