By Alexandre Meneghini
ZAPATA SWAMP NATIONAL PARK, Cuba (Reuters) - Ten baby crocodiles transferred from Sweden have reached a Cuban hatchery to strengthen the species and extend the blood lines of a pair of Cuban crocodiles former President Fidel Castro gave to a Soviet cosmonaut in the 1970s.
The hatchlings, a gift from a Swedish zoo in April, were delivered to the Zapata Swamp National Park's hatchery on Thursday after a 40-day quarantine in Havana. Scientists hope to boost a species thinned by loss of habitat and interbreeding with the American crocodile.
"They can be a new source of genotype to help preserve the species," said Etian Perez, a biologist at the Zapata Swamp hatchery, where 4,000 to 5,000 Cuban crocodiles are nurtured.
Each year the hatchery releases as many animals as scientists believe are ready for the wild, where they can grow to 2.5 to 2.8 meters long, about 8 to 9 feet.
Another 6,000 to 8,000 are in the wild, Perez said, numbers that Cuban officials are trying to keep from dwindling.
The newly arrived 21-month-old siblings, each about a meter (3 feet) long, could be held for a year or more before release, Perez said.
They were born to a pair of Cuban crocodiles Castro gave cosmonaut Vladimir Shatalov, who had nowhere to keep them and placed them in a Moscow zoo. The zoo transferred them in 1981 to Stockholm's Skansen zoo, where they have been breeding ever since.
Cuban crocodiles are restricted to the national park on Cuba's southern coast and the Isle of Youth further south. They are virtually no threat to humans, said Perez.
"To the contrary," he said, "humans are a threat to them."
(Reporting by Alexandre Meneghini and Daniel Trotta; Editing by Dan Grebler)