As oceanic temperatures continue to climb, harmful algal blooms have become an increasingly worrisome threat on the seabed floor of the Alaskan Arctic Ocean.
According to NOAA, a Global Ocean Monitoring and Observing-funded project conducted by the Woods Hole Oceanographic Institution (WHOI) found that warming waters are “causing algal blooms to occur more frequently in the Arctic Sea.”
The majority of these species are harmless, excluding the two found in the Alaskan sea: Alexandrium catenella, which can cause paralytic shellfish poisoning (PSP), and Pseudo-nitzschia, which can cause amnesic shellfish poisoning (ASP). Researchers have also detected high concentrations of dormant A. Catenella in the Chukchi Sea. As sea temperatures rise, the dormant algae bloom “has the potential to trigger recurrent blooms.”
According to the Alaska Beacon, 132 incidents of PSP and five fatalities were reported in Alaska between 1993 and 2021. PSP has also been reported as a contributor to mass bird fatality events. Alaska has since developed a coalition to oversee the growth and spread of harmful algae blooms, called the Alaska Harmful Algal Bloom Network. The organization is based in Homer, Alaska, U.S.A., and partners with the Kachemak Bay National Estuarine Research Reserve and Seldovia Village Tribe. Risks for growing levels of harmful algal blooms are being monitored in Kachemak Bay and Kotzebue, Alaska, as well as in the Northern Bering Sea, where a massive algal bloom was discovered in the Bering Strait in 2022.
“This was one of the largest and most toxic Alexandrium blooms ever observed in the United States and the world,” WHOI Senior Scientist Don Anderson told the Nome Nugget in 2023. “It did turn out to be largely composed of the most potent toxins that that organism can produce. That’s sort of a worst-case scenario. That bloom – and it could well be a very different case next year or the year after that – was nearly as toxic as it could be.”
The Alaska Department of Environmental Conservation (DEC) research published in 2024 found that livers of tomcod fish caught by students studying the blooms found “detectable levels of Alexandrium-produced sacitoxin and related gonyautoxin” that leads to PSP, according to the Anchorage Daily News.
