From the sea to the classroom: harmful algal blooms, northern sea otters, and engaging curriculum

Abstract

Harmful Algal Blooms (HAB) consist of a myriad of phytoplankton that can produce multiple potentially lethal biotoxins, which are ingested by shellfish as they consume algae in their diet. HAB events can occur when sunlight, nutrients, temperature, and turbidity conditions combine optimally. These bloom events are expected to increase as ocean temperatures continue to rise. The present study takes a multifaceted approach to evaluate the concentrations of paralytic shellfish toxins (PST), in northern sea otters (Enhydra lutris kenyoni), and provides a curriculum for students in grades 9-12 to support student’s conceptualization of microscopic phytoplankton and their roles in coastal ecosystems. The first aspect of the project evaluates PST congeners in northern sea otter stomach contents and body fluids using high-performance liquid chromatography post column oxidation from samples that were collected in Icy Strait from subsistence hunters near Gustavus, Alaska. The predominant stomach content species identified include butter clams (Saxidomous gigantea; n=7), horse clams (Tresus capax; n=16), horse mussels (Modiolus modiolus; n=14), pink neck clams (Leukoma staminea; n=2), and softshell clams (Mya arenaria; n=3). Body fluids analyzed were from 2015 samples, and included serum (n=5), whole blood (n=3), stomach fluid (n=5), and urine (n=5). The second aspect of the project includes the creation of a curriculum that consists of ecosystem-based discussions, field collection, laboratory safety, microscopy, and concludes with a creative evaluation. Students are evaluated using a creative media/method to explain how phytoplankton have the potential to negatively impact ecosystems and how such impacts may evolve in coming years, decades, or generations. This curriculum is geared towards non-traditional classrooms, Tribal or coastal communities, field courses, and multi-generational gatherings. Developing climate-focused curricula alongside traditional academic laboratory techniques increases accessibility to various user groups and supports fostering students who will go on to make climate-focused decisions in their daily lives, communities, and future careers.