Researchers look for clues in death of fin whale near Anchorage

Scientists are hoping to find out whether a beached fin whale in Southcentral Alaska has any connection to a mysterious die-off of large whales that began last year.

The 62-foot male fin whale was first reported stranded in upper Knik Arm on June 20, wrote NOAA spokesperson Julie Speegle.

The following morning, a team from the Joint Base Elmendorf-Richardson traveled to the whale, discovering it "alive but in poor condition," Speegle wrote. They stayed with the whale until the late evening.

"When they left, the tide was coming up, the whale was moving, and there was hope that it might become dislodged and swim away overnight," Speegle wrote.

On June 22, the whale was no longer in the same spot but was found dead in a different area of upper Knik Arm later that day.

The National Oceanic and Atmospheric Administration and a veterinarian from the Alaska SeaLife Center flew to the site the next day, collecting samples and attaching a buoy to the whale. The vet returned again on June 25, to collect more samples.

Speegle says while it's "fairly unusual" to see a fin whale in Knik Arm, it's not unusual for whales to become stranded in Southcentral Alaska.

This year, though, there's a heightened interest from scientists, who are examining results collected from whale carcasses to see whether they are related to an increase in whale deaths that started last year.

Whales began dying in greater numbers in the western region of the Gulf of Alaska in May 2015. Last August, NOAA declared the event an "unusual mortality event."

The cause of the deaths is unknown, Speegle wrote.

An unusual mortality event is defined as an unexpected, significant die-off of a marine mammal population. Sixty-two of these events have occurred in the U.S. since 1991; for about half of them, the cause of death has not been determined.

As for the beached fin whale, Speegle was not sure whether there are plans to dispose of the carcass. "In most cases, it is left for nature to take its course," she wrote.

A humpback whale was found dead in Hope on Monday, KTUU reported. In a separate incident, a humpback whale that had been tracked for 44 years was also reported dead this week in Southeast Alaska.

[Related: Mysterious deaths of Gulf of Alaska whales trigger stepped-up investigation.]