Killer whales linger in Alaska river, and scientists wonder why
Why have three killer whales spent three weeks in an Alaska river? And is the fresh water harming them?
Those questions have marine mammal scientists scratching their heads.
The whales have been spotted in the Nushagak River, not far from the village of Dillingham, about 330 miles southwest of Anchorage.
Their arrival was no cause for concern. Dillingham residents say whales are regular visitors in the fall.
But usually the killer whales, also known as orcas, stay downriver toward the ocean. And they have never been known to stay this long.
Then there's the spotty orange gunk visible on their backs and dorsal fins.
In an interview with The Times, biologist Barbara Mahoney of the National Oceanic and Atmospheric Administration said it looked as if the orcas had an infection that could be related to stress brought on by the animals being out of their normal habitat. It could be a fungus that only grows in fresh water, she said, or it might be there because the animals are moving more slowly.
"Nobody knows exactly what causes it," Mahoney said. "But that orange color has been witnessed before in other whales that wound up in fresh water."
In a statement, NOAA's National Marine Fisheries Service said it had just been alerted to the whale situation, and as of Thursday evening had no plans to intervene.
The agency is consulting with orca experts to decide what to do.
If the whales don't leave of their own accord in a few weeks, NOAA will most likely intervene, Mahoney said.
"We are monitoring the situation with the expectation that if things don't happen fairly soon we will have to have some type of response," she said. "By the end of October, things start freezing up around here."
-- Deborah Netburn
Photo: The killer whales in the Nushagak River, taken on Tuesday. Scientists may be able to use pictures like these to help identify the pods the whales belong to. Credit: John Sharp