The first of the European mink raised in captivity at Tallinn Zoo have been released into the wild on the island of Saaremaa.
The 10 animals are wearing transmitters so scientists can track them.
The European mink is critically endangered in the wild.
Some of the species brought to Saaremaa in the past, such as wild pigs and deer, have started becoming a nuisance. But Tiit Maran, a Tallinn zoo official who runs the mink program, says that if the mink survive, they should not be a nuisance to humans.
Maran said Saaremaa farmers may be worried about the introduction of mink alongside the marten. "But compared to what Saaremaa's large marten population does, the problem is negligible," Maran said. It should also not pose a threat to crayfish populations, he said.
Hiiumaa has a similar experience of trying to maintain dwindling populations of European mink and a local resident interviewed by ETV, Gennadi Kotsur, said there was no problem. Complaints from farmers over damage have turned out to be caused by martens, not mink.
Maran says that populating the two islands will give a possibility for long-term preservation. "And if all goes according to the worst-case scenario as it seems right now, at some point there might be only two islands in the world where the animals survive," Maran said.