Hooking Nome students on HAB research

Ice fishing is not the most common method of data collection. But for students at Nome-Beltz High School, a couple of afternoons in December spent jigging for tomcod was a gateway into some important lessons about the science behind Harmful Algal Blooms (HABs), algal toxins and maritime subsistence. 

“After the 2022 unprecedented HAB in the region, the kids now have a potential forever problem,” said Alaska Sea Grant marine advisory agent Gay Sheffield. “This is their world now, so we need to teach them. They should at least be cognizant of the words, the terms and the potential threat.” 

Sheffield served as an instructor at the December ice fishing event, at which roughly 30 high-school students learned about HABs, which occur when a toxic algal species quickly reproduces to high levels. The main species of concern in the Bering Strait region is the alga Alexandrium catenella, which can produce saxitoxin, a powerful biotoxin that can concentrate in shellfish and lead to paralytic shellfish poisoning (PSP) in both marine wildlife and humans. Warming northern oceans have improved growing conditions for Alexandrium, and HABs have recently been detected in the Bering Strait and Chukchi Sea, including a 2022 Alexandrium bloom that was one of the largest and most toxic ever observed worldwide. 

In 2023, Alaska Sea Grant, the Norton Sound Health Corporation Office of Environmental Health and the Nome Eskimo Community responded with a three-day class on HABs for Nome-Beltz High School science students. That, in turn, led to a longer-term student project to test whether toxins could be detected in tomcod livers, a popular subsistence food. While public concern about PSP centers on people’s direct consumption of shellfish, Sheffield noted there is evidence that it can also concentrate in the GI tracts, livers and kidneys of marine subsistence animals.

“Maritime subsistence foods are essential to the nutritional, cultural and economic well-being of our communities, period,” Sheffield said. “So this really throws a wrench in things to have this novel PSP concern.”

The students’ efforts showed the winter tomcod were safe to eat but that they contained small, harmless amounts of saxitoxin—a finding that even surprised experts in the field. The work proved an inspiration for the 2024 and 2025 iterations of the classes, which have evolved from a general discussion of HABs into a focused examination of potential PSP toxins in tomcod. 

The December 2025 program began with classroom sessions, in which students learned about both beneficial and harmful ocean algae, how toxins work their way up the food chain, and how both seawater and subsistence seafoods can be sampled and analyzed for algal toxins. Then, the group headed out to Nome’s inner harbor to collect their own field samples.

“Tomcod are a delicious part of our diet,” Sheffield said. “So we thought, we’ll get the kids doing a subsistence activity. Take them to the harbor, get them out there fishing, we’ll show them the tomcod, we’ll get them tested and we’ll show how to get the information to make informed decisions.” 

Sheffield noted that they were aiming for around 30 tomcod on the first trip, but the students had a wildly productive day and brought in around 300. Later in the week, they brought the samples to the science lab at the University of Alaska Fairbanks Northwest Campus, where they measured the fish and learned how to process them. The largest fish were set aside to be sent to Anchorage to be tested for biotoxin levels.

The students then headed back to the high school to prepare, bake and fry some of the remaining tomcod, adding a cultural dimension to the class and underscoring the fish’s significance as a regional cuisine. Some students later took a second ice fishing trip, sharing their catch of close to 100 fish with elders at the Norton Sound Health Corporation’s Quyanna Care Center nursing home.  

The community outreach and education dovetails with continued research into HABs in the Bering Strait region. Alaska Sea Grant recently concluded a five-year project to track saxitoxin in the Arctic food web, in collaboration with the NOAA Northwest Fisheries Science Center and Woods Hole Oceanographic Institution. The collaboration led to a second five-year project that incorporates the Nome Eskimo Community and focuses more specifically on tracking saxitoxin in key maritime subsistence species. Sheffield said a number of community partners are also collaborating on an effort to try to acquire a small HAB testing lab for Nome and the region.