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Rare White Killer Whale Sighted by NOAA Scientists Aboard NOAA Ship OSCAR DYSON
The primary purpose of the cruise was to determine pollock distributions near Steller sea lion haul-outs. Winter is a critical time for survival of the sea lions, and pollock is one of their primary food sources. This cruise was led by Chief Scientist Libby Logerwell, of the Alaska Fisheries Science Center Fisheries Interaction Team (FIT) in Seattle, Washington. This is a difficult season to survey the central and western Aleutian Islands due to the typically stormy weather experienced on the Bering Sea. Logerwell wanted to make the most of it stating, “Our [NOAA] labs in Seattle don’t have much data from the Central Aleutian Islands for the winter season, so this was an excellent opportunity to take along scientists from other groups to gather as much information about this environment as possible.” With a few empty bunks on board, Logerwell invited several other groups to participate in this cruise including a bird observer from the US Fish & Wildlife Service (USFWS) and a mammal observer from NOAA’s National Marine Mammal Laboratory (NMML).
During the cruise, oceanographic sampling was conducted to characterize the physical environment for pollock. Pacific cod were collected to study reproductive biology, and several organs from pollock, Pacific ocean perch and cod were collected for other projects to study back in Seattle. There were several killer whale sightings during the trip. Holly Fearnbach, a doctoral student and research biologist at NMML, is researching the influence of environmental variability on social structure and demography of fish-eating killer whales in Alaska. “There is an abundance of data for killer whales around the Aleutian Islands,” Fearnbach reported, “but not during the winter months”. Fearnbach wanted to see if there were changes in group structure--if there were areas with more or less female, male, older or younger individuals in the group, or if the sizes of the groups were varied. Under the authorization of Fearnbach’s NOAA research permit, the OSCAR DYSON was able approach the whales sighted during the survey to obtain photographs for identification.
On February 23, 2008, a third pod of killer whales was spotted approximately two miles off of the Kanaga Volcano. This group, however, had an unusual member. Unlike its dark black companions, there was one whale that did not look like the others--it was white! This made for an extremely exciting encounter for the crew and scientists on board the OSCAR DYSON, as well as for other NOAA scientists studying orcas in Alaska. “With hundreds of killer whales documented around the Aleutian islands, it is equivalent to finding a needle in a haystack,” Fearnbach stated. This whale’s prominence makes it a possible indicator for studying movements of killer whales. A white killer whale has been sighted previously in the Aleutian Islands, as well as in the Bering Sea and off the Russian Coast. Fearnbach plans to examine the photos of that whale as well as the one she observed on this cruise to determine if this is the same whale.
A condition known as Chediak-Higashi Syndrome could be a cause for the difference in pigmentation of this whale. Inherited from the parents, the rare Chediak-Higashi Syndrome is a disease of the immune and nervous system. One of the most distinct ways to tell if an animal is a true albino is to see if it has a pink eye. No one was able to obtain a picture of the eye of this individual, so the photographs will have to be compared to the other white whale sightings in the area to determine if it is a match--and a true albino. Tamara Mills, USFWS, thought the cruise was excellent. “With limited survey efforts in the area during the winter, I had no expectations of what I would see out there, and was surprised to encounter juvenile short-tailed albatross, laysan albatross and peregine falcons.” In a partnership with NOAA, the USFWS provides seabird observers for as many ships as possible that cruise the Bering Sea to obtain their data throughout the year. Also encountered on the cruise were Dall’s porpoise, Steller sea lions and sperm whales. There were 5 total killer whale sightings, with 4 of them being of the fish-eating or resident variety. The NOAA Ship OSCAR DYSON and its crew have conducted humpback whale, right whale, and ice seal surveys in the Bering Sea for the NMML. There is an ice seal cruise scheduled with NMML for later this season. Story submitted by Colleen Peters
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With icy decks and a windy forecast, the 
