JUNEAU — Aug. 21, 2015 — Federal investigators are trying to determine why at least 30 large whales have died in Alaska since May, according to cnn.com.

The National Oceanic and Atmospheric Administration (NOAA) called the occurrence “the first ‘unusual mortality event’” ever declared for the animals in Alaska, noted the article. A bird species, common murres, have also experienced widespread deaths.

Unusual whale deaths have also been reported in British Columbia, Canada, stated the article. Most years see less than 15 large whales stranded.

NOAA suspects that biotoxins like algae could be the culprit, reported the article. Samples are being collected to test for such contaminants, but the results could take months or years.

“Biotoxins will be one of the top priorities, but not the only priority that we’ll be looking at to rule in or rule out whether it’s playing a role in this death investigation and these mortalities, both in Canada and the U.S.,” said NOAA Fisheries scientist Teri Rowles in the article.

A large algal bloom currently stretches from central California to Washington, shared the article, and it could have impacts on Alaskan waters.

NOAA has recorded 61 unusual mortality events since 1991, noted the article. Algal bloom biotoxins account for most of the recent occurrences.

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