humpback

Toxic algae and West Coast marine life

June 5, 2025 By EarthWise Leave a Comment

Over the first several months of this year, hundreds of sea lions, dolphins, and seabirds have fallen ill or died after eating sardines or anchovies that had been feeding on an algal bloom along the California coast since winter. The biotoxin in the algae accumulates in the feeder fish.

Two cases of whales dying from the biotoxin have been confirmed by two nonprofit organizations tasked with testing dead mammals. These were a humpback that washed ashore in Huntington Beach in January and a minke whale found dead in Long Beach in April.

This is the fourth year a row that California has experienced major algal blooms. Warmer waters are causing blooms to be bigger and more damaging than they have been before. They enter into new areas and contaminate the food web for longer. The warmer waters accelerate algae growth that is further fueled by nutrients that rise to the surface from deeper colder waters driven by winds that blow parallel to the coast. This year’s algae event started earlier than usual and is lasting longer than normal.

More than a dozen animal rescue and rehabilitation groups that form NOAA’s West Coast Marine Mammal Stranding Network are providing resources to try to respond to the situation. At the Marine Mammal Care Center in Los Angeles, more than 80 sea lions and seals were being treated for domoic acid poisoning, the result of ingesting algae neurotoxin. Since February, it has cared for more than 300 poisoned animals.

Marine mammals are sentinel species for humans who also consume seafood. The West Coast ocean ecosystem is currently filled with toxins.

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California Toxic Algal Bloom Blamed for Months-long Marine Life Poisoning

Photo, posted March 26, 2025, courtesy of Marnee Jill via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Return Of The Blue Whales | Earth Wise

December 21, 2020 By EarthWise Leave a Comment

An international research team has revealed that critically endangered Antarctic blue whales have returned to the sub-Antarctic island of South Georgia, 50 years after whaling just about wiped them out. Other recent research has found that humpback whales are also returning to the region.

Blue whales were commonplace off South Georgia before 20th century industrial whaling taking place between 1904 and 1971 killed over 42,000 of them there. Most of that number were killed before the mid-1930s. As a result, blue whales essentially vanished from the region. Whale survey ships sighted only a single blue whale between 1998 and 2018.

But things have changed in recent years. A survey this past February resulted in 58 blue whale sightings and numerous acoustic detections. Although commercial whaling was banned in the area in the 1960s, it has taken a long time for the whales to make a comeback.

Researchers are not sure why blue whales have taken so long to return to the area. It may be that so many were killed over the years that the remaining population had little or no cultural memory of South Georgia Island as a foraging ground, and that it is only now being rediscovered.

In total, 41 individual blue whales have been photo-identified from South Georgia over the past 10 years, although none of those matched the 517 whales in the current Antarctic blue whale photographic catalogue. Dedicated whale surveys are difficult in a region known for its harsh weather and inaccessibility but are crucial to the future management of South Georgia’s seas. In any case, researchers see the recent sightings as a very positive step forward for conservation of the Antarctic blue whale.

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Blue whales return to South Georgia after near extinction

Photo, posted September 7, 2007, courtesy of the NOAA Office of National Marine Sanctuaries via Flickr. Photo credit: NOAA.

Earth Wise is a production of WAMC Northeast Public Radio.

Whales In The Big Apple

July 12, 2017 By EarthWise

For the first time in a century, humpback whales have returned to the waters of New York harbor. These are not rare sightings, either. The whales are showing up in enough numbers that a company is taking tourists out into the harbor to see whales with a backdrop of Manhattan skyscrapers.