More than 11,000 tadpoles born in the Detroit Zoo have been released in Puerto Rico in an effort to restore an endangered toad to the Caribbean island.
The Detroit Zoological Society says the Puerto Rican crested tadpoles left the Detroit area Wednesday and were released 24 hours later in a forest pond.
The zoological society says more than 52,000 other Detroit zoo-born tadpoles have been shipped to Puerto Rico over the past decade. They are monitored to determine if the toads are surviving and breeding.
The toads thrived on Puerto Rico until sugar growers introduced a foreign toad they hoped would eat pests that feed on sugar cane. The introduced toad ate the native toad's young and took over its habitat. Human development eliminated much of the native toad's range.