White
Killer Whale Spotted—Only One in the World?
Scientists were studying acoustic and
social interactions among whales and dolphins off the North Pacific's Commander
Islands (map) when the team noticed a six-foot-tall (nearly two-meter-tall)
white dorsal fin jutting above the waves—hence the whale's new name: Iceberg.
"The reaction from the team for the
encounter, which happened on an ordinary day for spotting and photographing the
whales, was one of surprise and elation," researcher Erich Hoyt said via
email. Though he wasn't aboard the boat, Hoyt co-directs the Far East Russia
Orca Project (FEROP), which had organized the expedition.
Though Iceberg's moniker is new, he may be
the same killer whale scientists spotted in 2000 and 2008 in Alaska's Aleutian
Islands (map), Holly Fearnbach, a research biologist at the University of
Aberdeen in the U.K., said by email.
For one thing, Iceberg and the previously
seen whales look very similar, Fearnbach said.
Furthermore, each of the three white whale
sightings were among about a dozen family members, all bearing the typical
black-and-white pattern, Fearnbach said.
And it wouldn't be odd for Iceberg to have
made the Russia-to-Alaska crossing. Fish-eating North Pacific killer whales
have been observed migrating more than 1,240 miles (2,000 kilometers). Their
mammal-eating cousins cover smaller ranges.
The whale seen in 2000 and 2008 was darker
and more mottled than Iceberg, FEROP's Hoyt noted, though the coloring can
change seasonally due to algae on the skin, "which would tend to make a
white animal look darker."
Overall, Aberdeen's Fearnbach said,
"it is highly possible they are the same whales—but we cannot be certain
until a match is confirmed" by closely analyzing photographs of the three
sightings.
White Whale a Mystery
The 22-foot-long (7-meter-long) Iceberg is
probably not a true albino, since he has color on his saddle—the area behind
his dorsal fin—FEROP's Hoyt said.
"Iceberg may or may not be an albino.
We really don't know," said Hoyt, also a senior research fellow at the
Whale and Dolphin Conservation Society.
One way to find out would be to see if
Iceberg's eyes are pink and unpigmented—a sure sign of albinism, Hoyt said.
(See pictures of albino animals.)
Scientists have observed other killer
whales with a condition called Chediak-Higashi syndrome, a rare disease of the
immune and nervous system that affects coloration, Fearnbach said.
But most animals affected with Chediak-Higashi
don't survive to adulthood, meaning it's unlikely Iceberg—a mature male of at
least 16 years—has the disease. The male seen in 2000 and 2008, if different
from Iceberg, also didn't have the disease.
"I do not know a lot about other
genetic conditions that may cause such light pigmentation, but hopefully he
will be seen again and we can collect a genetic sample," Fearnbach said.
By: Jennifer Jude Ann
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