Bloomin’ Awful

Thanks to climate change, these toxic algae keep spreading.

February 18, 2016

Photo: NOAABears feeding on a fin whale carcass in Larson Bay, Alaska

The Pacific saw the biggest toxic algal bloom on record last year, from the Aleutian Islands to the Bering Sea. And it was a nightmare for life in the Pacific, closing fisheries, sending countless sea lions to rehab, and killing at least 30 whales (here, a group of grizzlies feasted on the carcass of a fin whale in Larson Bay, Alaska, last summer). In 2016, the damage continues: Last month, thousands of birds mysteriously washed up on the shores of Prince William Sound. 

Researchers know that the algal sludge contains heavy doses of domoic acid and saxitoxin, neurotoxins that are deadly to marine mammals in high doses. Now, a new study from the National Oceanic and Atmospheric Administration finds that the bloom of algae is headed as far north as the Beaufort and Chukchi Seas, its growth spurred by warming ocean temperatures, melting sea ice, and sunlight.

“The environment is changing very rapidly in Alaska,” says Kathi Lefebvre, a NOAA Fisheries research scientist. “These ecosystems have developed over millions of years, so the chances they’re going to be changed for the better overall are slim.” 

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