Low-cost monitoring of HAB toxins in Kachemak Bay
Harmful algal blooms (HABs) happen every year in Alaska and are increasing in frequency, likely due to rising ocean temperatures and other factors. HAB algae contain potent neurotoxins that accumulate in filter-feeding shellfish like clams, oysters, and mussels and cause paralytic shellfish poisoning. They can also accumulate in the marine food web, leading to poisoning in fish, sea birds, and marine mammals. Many Alaskan communities rely on the ocean for food security, so fully understanding the extent and impact of HAB events is of paramount importance.
A few years ago, scientists from the Woods Hole Oceanographic Institution discovered a massive toxic algae cyst bed in the Arctic, nearly the size of California lurking in the Chukchi and Beaufort Seas. These cysts are a long-dormant seed-like stage of the algae that produce potent neurotoxins present in HABs. As the ocean warms, germination in these cyst beds may increase, leading to even larger bloom events in the Arctic. Since the discovery, there has been an increased focus on HABs.
Despite the growing concern, Alaska does not have a statewide regulatory agency that monitors HABs. This is somewhat due to the complexities and cost of monitoring and testing for HABs across Alaska’s remote and varied ecosystems. Also, regulatory guidance is often geared toward the Lower 48 states. Consumers often either take a risk or have to seek out testing food to make sure it is safe to eat; “[in many areas] it’s harvest at your own risk,” according to Alexandra Ravelo, a post-doctoral researcher at the International Arctic Research Center. Ravelo is a co-principal investigator, alongside Rosie Masui of the University of Alaska Anchorage, on a University of Alaska Faculty Initiative Fund award led by Lauren Sutton, research coordinator at the Kachemak Bay National Estuarine Research Reserve, to pilot a low-cost method for monitoring harmful algal bloom (HAB) toxins in Kachemak Bay.
Some communities in Alaska build their own testing facilities or rely on local agencies and practices, according to Ravelo, but others have to send tissue samples out to distant testing centers. For example, if you are in Southeast Alaska, you can submit clam or mussel samples to the Southeast Alaska Tribal Ocean Research. However, if you are in Anchorage, you must send them to the, which is expensive and time-consuming. Alaskan Indigenous communities have also long relied on traditional knowledge systems for monitoring HABs.
For this project, the researchers partnered with the University of Alaska Anchorage’s Kachemak Bay National Estuarine Research Reserve to place inexpensive devices in Kachemak Bay to collect dissolved toxins for testing. Solid Phase Adsorption Toxin Tracking (SPATT) are circular devices made of an embroidery mesh with a tablespoon of adsorbent resin that captures and accumulates dissolved toxins from the water column. They are relatively inexpensive and easy to maintain.
Throughout the summer, the team will collect the samples and analyze them using an Enzyme-Linked Immunosorbent Assay, or ELISA, to determine total toxin levels. ELISA is a rapid, cost-effective biochemical test used by water utilities and environmental agencies to detect and quantify specific algal toxins in water and biological samples. This “very simple piece of information can help us understand the bigger picture of how toxins fluctuate in Katchemak Bay,” said Ravelo. It will also confirm the viability of using these simple measurement devices to enable more affordable localized testing.
Alaska’s communities and ecosystems are diverse, so multiple practical tools are needed rather than having a one-size-fits-all system. Ravelo and her group hope that SPATTs could become part of the “toolbox” for regional monitoring of toxins across the state alongside the methods already in use.
Additional References
Anderson, D. M., Fachon, E., Pickart, R. S., Lin, P., Fischer, A. D., Richlen, M. L., Uva, V., Brosnahan, M. L., McRaven, L., Bahr, F., Lefebvre, K., Grebmeier, J. M., Danielson, S. L., Lyu, Y., & Fukai, Y. (2021). Evidence for massive and recurrent toxic blooms of Alexandrium catenella in the Alaskan Arctic. Proceedings of the National Academy of Sciences, 118(41).
University of Alaska Fairbanks. (2026). 2026 FIF Awardees | Academics, Students & Research. Alaska.edu.