NCCOS Assists Response to Multispecies Mortality Event in St. George Island, Alaska

A rapid, multi-agency response is underway on St. George Island, Alaska, to investigate a multispecies mortality event linked to a harmful algal bloom, with concerns that paralytic shellfish poison (PSP) toxins may be affecting local wildlife and human health.

AI Comment from GPT 5:

This post describes a rapid, multi-agency response to a multispecies mortality event on St. George Island following detection of an Alexandrium bloom in the southeastern Bering Sea, with NCCOS HAB Event Response funds supporting sampling to determine whether paralytic shellfish toxins are implicated. The effort aims to quickly assess risks to wildlife, human health, and subsistence resources, with further food web sampling planned if PST exposure is confirmed.

Recent LEO posts help frame the context and urgency. Testing on St. Paul in August 2024 documented widespread saxitoxin exposure in northern fur seals and benthic fishes during a die-off, linking HAB toxins to marine mammal and fish mortality in the same region (Harmful Algal Blooms Linked to Deaths of Northern Fur Seals in the Southeast Bering Sea). HAB activity has been building across multiple years: a large, highly toxic 2022 bloom posed risks across the food web and prompted advisories and targeted testing despite few reported human illnesses (2022 Bering Sea algal bloom was one of the largest, most toxic ever observed nationwide); in 2023, elevated Alexandrium catenella levels in Bering Strait waters triggered warnings for subsistence seafood and underscored the need for ongoing monitoring as risks were evaluated (Harmful algae bloom detected in Bering Strait waters). Researchers have also noted that HABs are becoming more common and locally seeded in northern waters as cysts establish and grow in warming bottom waters, increasing the potential for ecosystem and human health impacts (Latest research from Woods Hole finds HABs growing locally in Northern waters; How will the Bering Strait respond to harmful algal blooms?). Earlier observations of low but notable toxin levels and high cyst concentrations in sediments foreshadowed today’s conditions by pointing to enhanced transport and local seeding in the northern Bering and Chukchi Seas (Low Levels of Algal Toxins in Northern Bering Sea of Interest to Scientists and Residents). Together, these related posts illuminate why rapid testing around St. George is critical now and provide precedent for tracing PST movement through the food web during mortality events.