Hybridization threatens Arctic species

LOS ANGELES – As the world heats up and polar ice melts, different types of bears, whales and seals could meet and mate – but these unions may be far from happy, researchers said Wednesday. In fact, interspecies sex brought on by the melting Arctic ice could lead to the extinction of many endangered Arctic animals, the scientists said in an article published in the journal Nature.

At least 22 species are at risk of hybridizing in 34 different combinations, according to a team led by Brendan Kelly, an Alaska-based evolutionary biologist with the National Oceanic and Atmospheric Administration. The pairings include polar bears and grizzlies; narwhals and beluga whales; and various assortments of seals.

Since hybrid offspring – or their offspring, in turn – are often infertile, maladapted or sickly, much of the genetic biodiversity of the Arctic could be lost, the scientists warned.

Kelly said the report “is sort of a call to arms to encourage our colleagues around the Arctic to recognize this may be going on.”

Although Arctic species rarely interbreed, many are capable of doing so. In 2006, a bear with a patchy white-and-brown coat was shot in the Canadian Arctic. Scientists suspected – and DNA-typing later confirmed – that the animal was polar bear-grizzly bear hybrid.