Matthew Gribble, Ph.D.

Using statistical models to understand harmful algal bloom impacts

Harmful algal blooms occur when certain environmental conditions trigger the rapid growth of phytoplankton, posing serious risks to marine life and people. These events can quickly deplete oxygen in localized areas of the ocean, causing mass deaths of fish and other marine life, and can produce toxins with immediate or long-term health impacts on exposed organisms. In humans, exposure to these toxins is most often linked to consuming seafood from affected areas, disproportionately affecting coastal communities that rely on clams, mussels, and oysters as traditional food sources.

Matthew Gribble will use his Pew-Hoover fellowship to apply an advanced statistical technique called a hidden Markov model to better understand the distribution, frequency, and impacts of chronic exposure to algal bloom toxins. His work will focus on southeast Alaska, where Alaska Native communities have been repeatedly affected by harmful algal blooms, and Andalucia, Spain. He will determine how often areas have been exposed to algal blooms in the past, supporting insights into the health effects of harmful algal toxin exposure. He will also test hypotheses about the environmental factors that drive algal blooms to help scientists predict harmful events and inform seafood testing programs.

To learn more about Dr. Gribble, read his bio.

See the full list of 2026 Pew marine fellows.