The Puerto Rican crested toad is the only native toad of Puerto Rico. It was listed as threatened by the United States Fish and Wildlife Service in 1987 (USFWS, 1992) and Critically Endangered by the International Union for Conservation of Nature and Natural Resources (IUCN, 2004). One of the main factors leading to the decline of crested toads in Puerto Rico is habitat alteration. Many of the temporary breeding ponds in the north have been drained for agricultural and urban development as well as mosquito control. In Guánica National Forest, the practice of draining the last remaining breeding pond for easier access to the beach was stopped after the toads were rediscovered in the area in 1984. Another suspected major contributor to the decline of the toad is the introduction of the giant marine toad, R. marina. The crested toad is a much smaller species and must compete with the marine toad for egg laying sites, food and shelter. Predation of juvenile crested toads by marine toads has also been observed. Other known predators include feral dogs, cats, mongoose, anoles, ground lizards, crabs and herons (USFWS, 1992 and Canals, 2005). The last remaining population at Guánica is highly vulnerable to environmental catastrophe. Hurricanes, tidal waves, floods, prolonged drought, increased salinity levels and rising sea level could wipe out the entire population or reduce it to unsustainable numbers.
Population estimates (accumulated for the past 30 years during breeding events) fluctuate between 300 to 3,000 individuals for the remaining wild population of toads in Tamarindo, Guánica. There are no population estimates for crested toads living in Cienega and Ventana, and the six reintroduction sites across the island. Increased monitoring and research is needed for evaluation of all areas.
Historical Timeline of Events for the Puerto Rican crested toad:
The crested toad was first described in 1868 (Cope, 1868), has only been reported from 19 sites in Puerto Rico and was believed extinct by the mid 1960’s (Garcia-Diaz, 1967). The timeline below depicts major events regarding the rediscovery of the toad and significant recovery efforts that follow.
1967: crested toad rediscovered in Isabella- northern part of the island
1974: northern population found in Quebradillas (Estremera, 1990)
1980: partnerships developed and crested toads reproduce in captivity
1982: first reintroduction in north occurs- Quebradillas
1984: southern population discovered in Guánica Commonwealth Forest (Moreno, 1985); PRCT listed as endangered by PRDNER; AZA PRCT SSP formed
1987: federally listed as threatened by USFWS
1992: last of the northern toads observed in Quebradillas (Ross, 2007); reduced to single population in Guánica; first reintroduction in the south occurs- Manglillo Grande
2006: primary reintroduction site established in north- El Tallonal, Arecibo
2008: discovery of a second population of PRCT in south- Ventana; reintroductions begin in second southern site- Gabia, Coamo
2010: population of crested toads rediscovered in Cienaga, Yauco- south
2012: reintroductions occur at three new sites: Rio Encantado, Cailes and La Esperanza, Manati in north; Los Conventos, Guayanilla in south
One of the primary goals identified for the conservation of this species is to foster island-wide awareness for this rare endemic toad. Puerto Ricans are very fond of their beloved coquí (Eleutherodactylus coqui), and sounds and images of the frog can be heard and found everywhere. Unfortunately, most Puerto Ricans have never heard of the crested toad, nor are they aware of its plight. Historically, the original common name for P. lemur was “sapo concho,” but the name soon became synonymous for the more commonly seen R. marina, making conservation efforts difficult. As a result in 2003, the recovery working group changed the common name for P. lemur to “sapo concho Puertorriqueño” and the name for R. marina to “sapo común” to differentiate between the two species.