Archive: Detroit Zoological Society Takes Big Leap to Save Critically Endangered Toad

More than 11,000 zoo-born Puerto Rican crested tadpoles released into the wild

June 12, 2018

ROYAL OAK, Mich., 

Thousands of Puerto Rican crested toad tadpoles – 11,226 to be exact – left Detroit for Puerto Rico on June 6, where they will be released in the El Tallonal biological reserve as part of a federal program to restore this critically endangered amphibian. These tadpoles join the more than 52,000 Detroit Zoo-born tadpoles released in Puerto Rico over the past decade. Fifteen of the tadpoles remain at the Detroit Zoo’s National Amphibian Conservation Center for future breeding.

“With nearly half of the world’s known 7,878 amphibian species threatened with extinction due to habitat loss, climate change, pollution, infectious diseases and other factors, bolstering the population of these toads in their natural environment is extremely gratifying and a real win for conservation,” said Dr. Ruth Marcec, director of the National Amphibian Conservation Center.

Detroit Zoological Society (DZS) amphibian staff spent more than 12 hours counting and packing the tadpoles into Styrofoam-protected shipping boxes for their journey. Heavy-duty fish shipping bags were used, doubled up and filled with oxygen to keep the tadpoles healthy and safe en route. Approximately 24 hours later, the tadpoles were release in their new home – a pond located in a well-protected forest in Puerto Rico.

“As the tadpoles develop and grow, they will add to the wild population and, one day, hopefully, produce many more thousands of tadpoles,” said Dr. Marcec.

Puerto Rican crested toads reach maturity at approximately one and a half years of age. The population in Puerto Rico is monitored to determine if released animals are surviving and breeding. The breeding program has shown to successfully boost the wild population.

The Puerto Rican crested toad (Peltophryne lemur) has greenish-brown pebbled skin and marbled golden eyes. It grows 3-4 inches long and has the ability to nearly flatten its body completely to fit into tiny crevices. These toads can be challenging to spot in their habitat at the Detroit Zoo, but visitors can often see their large eyeballs and pointy, hooked noses peering out from under their naturalistic limestone structures.

The National Amphibian Conservation Center opened at the Detroit Zoo in 2000 and was distinguished as the first major facility dedicated entirely to conserving and exhibiting amphibians. Dubbed “Disneyland for toads” by The Wall Street Journal, it houses a spectacular diversity of frogs, toads, salamanders, newts and caecilians. The award-winning, state-of-the-art facility is world renowned for amphibian conservation, care, exhibition and research.