In 2019, Willapa Grays Harbor Oyster Growers Association (WGHOGA) and the Department of Ecology (Ecology) agreed to work together to identify an integrated approach to control the burrowing shrimp infestation that is devastating oyster beds in Willapa Bay and Grays Harbor.
They agreed the Integrated Pest Management (IPM) plan would include chemical and non-chemical controls, with the goal of minimizing chemical use and maximizing the effectiveness. They also established a IPM Working Group with representatives from the Departments of Agriculture, Natural Resources, Commerce, Washington Sea Grant, the Conservation Commission. The Shoalwater Bay Indian Tribe is now represented in the group.
The Working Group is developing the framework for identifying “treatments to reduce populations of burrowing shrimp to below established thresholds using biological, cultural, mechanical, and chemical control methods,” and “evaluating the environmental effects and efficacy of burrowing shrimp treatments.”
To inform this process, the IPM Working Group has commissioned several studies to develop a replacement for imidacloprid and create the framework for a new IPM plan. The initial stages of this research included lab studies to identify potential low toxicity insecticides or repellents that may be implemented into an IPM. Studies to better understand burrowing shrimp populations, density, and recruitment patterns.