Animal Conservation: Detroit Zoo Sent 11,000 Toads to Puerto Rico to Grow Native Population

Puerto Rican crested toad, Peltophryne lemur U.S. Fish and Wildlife Service

Detroit Zoo officials announced on Tuesday that they are sending 11,226 tadpoles to Puerto Rico as part of a program aimed at protecting the natural population of a local toad species. The Puerto Rican crested toad is critically endangered, the zoo said in a news release, and the tadpoles will head to the El Tallonal reserve as part of a federal program.

The tadpoles will be joining the 52,000 already sent by the Detroit Zoo in the last decade to Puerto Rico. Just 15 will be kept in Michigan to continue breeding.

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"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 Ruth Marcec, director of the National Amphibian Conservation Center.

Amphibian staff from Detroit Zoological Society took 12 hours to count all of the tadpoles before they were packed into heavy duty fish shipping bags filled with oxygen and put into styrofoam-protected shipping containers. It only took around 24 hours before the tadpoles were once again free in their new Puerto Rican pond home.

"As the tadpoles develop and grow, they will add to the wild population and, one day, hopefully, produce many more thousands of tadpoles," explained Marcec.

According to the zoo, the breeding program "has shown to successfully boost the wild population." The tadpoles will be monitored to make sure they are breeding and surviving.

The toad is also known as the Lowland Caribbean Toad, according to the IUCN Red List, which noted that the toad is classified as critically endangered due to population decline in the last decade "estimated to be over 80 percent."

The zoo describes the toad as having "greenish-brown pebbled skin and marbled golden eyes." It also has the ability to flatten its body, which grows to around 3-4 inches long, to fit into tiny spaces.