Summary
POTENTIAL Harmful Algal Bloom Event in Kachemak Bay Homer, Alaska, 7/22/2025
POTENTIAL Harmful Algal Bloom Event in Kachemak Bay
Homer, Alaska, 7/22/2025
The Kachemak Bay National Estuarine Research Reserve (KBNERR) monitors phytoplankton (aka microalgae) on a weekly basis in Kachemak Bay from May-Oct. A network of volunteers and partners send water samples to us to analyze and identify the phytoplankton. We publish our findings in a weekly report. Some algal blooms have the potential to create toxins that are harmful to shellfish, birds, marine mammals, and/or human health. If we detect a bloom, it is highlighted in our weekly report. The KBNERR is NOT a regulatory agency. Alaska is a “Harvest at your own risk” state when it comes to shellfish.
Sign up to receive Phytoplankton Weekly Reports by email, and learn more: https://kachemakbayreserve.org/science/monitoring/#algal-blooms
Current Situation
Phytoplankton blooms in the summer are common, and most of them do not produce toxins. Pseudo-nitzschia (a chain-forming diatom) has been detected at bloom levels in Kachemak Bay since July 4th, 2025, and this diatom has the potential to produce the toxin, Domoic Acid (DA). Domoic Acid is associated with Amnesic Shellfish Poisoning. Learn more about harmful algal blooms in Alaska and this specific kind of shellfish poisoning here. We do not yet know if the current bloom event has produced the DA toxin. KBNERR regularly sees Pseudo-nitzschia blooms in Kachemak Bay, and KBNERR has not detected the DA toxin associated with these blooms in the past. Mussel samples have been collected and sent to AK Department of Environmental Conservation for testing, and results will be shared when available. We are working with the Alaska Harmful Algal Bloom (AHAB) Network partners, state, federal agencies, and Tribes, to coordinate communication and monitor the situation. We don’t anticipate having DA toxin testing results until the end of the week. We will keep the public informed as we learn more.
There have been some recently observed bird deaths and marine mammal strandings in Kachemak Bay, and we do not know if they are related to each other or to this bloom event. Sampling and coordination with federal, state, and Tribal partners is underway. Please use the following hotlines if you notice anything unusual:
Human health concerns, If you are experiencing symptoms of shellfish poisoning call 911 or your local health care provider immediately. Alaska Health Care Providers who suspect or diagnose a disease that represents a public health emergency should immediately call 1-907-269-8000 during business hours or 1-800-478-0084 after hours.
Birds – US Fish & Wildlife Service is leading this effort. For your safety, do not handle any sick birds or birds that are found dead. If you observe dead seabirds or encounter a sick or dead wild bird and the cause is not immediately apparent please call the Alaska Sick or Dead Bird Hotline at (866)-527-3358. Instructions on how to report: www.fws.gov/alaska-bird-sick-abandoned-injured-dead
Marine Mammals – NOAA Fisheries Alaska Statewide 24-Hour Stranding Hotline. For injured/stranded whales, seals, sea lions, porpoises, and dolphins. Phone: (877) 925-7773 or (877) 9-AKR-PRD. Or the AK SeaLife Center: 888-774-7325
For questions and concerns about Harmful Algal Blooms, email Rosie Masui, KBNERR’s AHAB Engagement Lead: rmmasui@alaska.edu
*For information on regulations associated with the subsistence harvest of shellfish in Cook Inlet please contact the Alaska Department of Fish and Game office in Homer at 907-235-8191.
*The state of Alaska’s stance for wild shellfish is “harvest and eat at your own risk.”
*KBNERR is not a regulatory agency
*All commercially harvested shellfish are strictly tested for PST and regulated by the DEC and considered safe for consumption. 877-233-3663 https://dec.alaska.gov/eh/fss/shellfish/recreational-harvesting/