A group of scientists aboard the NOAA research vessel Oscar Dyson in the North Pacific spotted a rare white killer whale in the Aleutian Islands on February 23, among a pod of normally colored whales.

At the moment of their discovery, the scientists were about two miles off Kanaga Volcano, part of Alaska's Aleutian Islands, where the research ship was conducting an acoustic survey of pollock near Steller sea lion haulout sites.  

The nearly mythic creature was initially noticed by Holly Fearnbach, a research biologist with the National Marine Mammal Laboratory in Seattle who also photographed the seemingly albino whale.

"I had heard about this whale, but we had never been able to find it," said Fearnbach. "It was quite neat to find it."

According to John Durban, a research biologist at National Oceanic and Atmospheric Administration's Alaska Fisheries Science Center in Seattle, the whale, which has a white saddle area while other parts of its body have pigmentation, is probably not a true albino.

Experts say the white coloration could be the result of Chediak-Higashi Syndrome, an inherited condition of the immune and nervous system.

A similarly looking whale was spotted years ago in the Aleutians, much less scientifically documented.  However, such whales have eluded researchers since. White orcas have previously been reported in the Aleutians, the Bering Sea and the Russian coast.

"Despite the typical stormy weather that makes research operations very difficult in the winter, the scientific team on Oscar Dyson has been pulling in a huge amount of planned research data," said Doug DeMaster, director of the Alaska Fisheries Science Center. "Extraordinary sightings like this white whale are icing on the cake."

Killer whales, also known as orcas, are common to that part of the world. They are familiar to people because they have been kept in public aquariums, where they can live for decades.

The scientists are currently trying to identify if the whale, which appears to be a healthy, adult male about 25 to 30 feet long and weighing upward of 10,000 pounds, has been spotted before.