Many plants and animals have been introduced to Newfoundland, either by chance or deliberately. Moose, snowshoe hare, American red squirrel, eastern chipmunk, and masked shrew, and others, were brought to the island through specific wildlife mandates. Moose were introduced in 1904 and are now the dominant ungulate on the island. An unusual experiment conducted in 1964 involved relocating a small herd of bison onto Brunette Island in Fortune Bay. The last of these animals is thought to have died by 1994. Rats and mice were unintentionally introduced while mink escaped from fur farms. Coyotes are a very recent addition to the fauna of Newfoundland. How coyotes got onto the island is still debated by wildlife officials, but it is probable that they crossed the ice from Cape Breton Island in the 1980s. Newfoundland has no native amphibians, but frogs were introduced onto the island in the 1860s and toads almost a century later.