Questions Remain About Pesticide Proposal To Combat Burrowing Shrimp Infestation

Oct 30, 2017

A proposal to spray a neurotoxic pesticide on oyster beds in Southwest Washington is back on the table. Growers in Willapa Bay and Grays Harbor are looking for ways to address an infestation of burrowing shrimp.

The state is taking comments on the controversial plan through Wednesday.

Public outcry led the state Department of Ecology to withdraw the grower’s first plan to use the neonicotinoid imidacloprid in 2015. The new plan involves spraying a smaller acreage at first and doing it with ground equipment instead of helicopters.

Annie Herrold is a fourth generation oyster farmer in Willapa Bay who supports the plan. She says after years of research following the phase out of the pesticide Carbaryl in 2012, Imidacloprid is their best and only option. The industry organization she is part of has produced a detailed web site that outlines their plan and attempts to address any concerns.

“I mean we’re not even using an amount that’s potent enough to kill the shrimp. It basically immobilizes them,” Herrold said.

According to their plan, the shrimp would suffocate, so they stop turning oyster beds to quicksand, where nothing grows.  

“Without this we – many of us will lose our farms,” Herrold said.

But environmentalists such as Olympia resident Nathan Donley, a senior scientist at the Center for Biological Diversity who testified at a recent hearing and penned an op-ed in the Seattle Times, argue the risks are too great because more than just the targeted shrimp will be affected.

“And we just don’t have enough scientific data to come to a confident conclusion that this won’t have serious ecological consequences.”

He also says the smaller application described by some as a "light touch" could lead the remaining shrimp to develop immunity more quickly, making it “at best, a temporary solution.”

Proponents of the plan say they’ll keep looking for better remedies. But even some oyster growers in the area, including the largest, Taylor Shellfish, are still not on board because of public concern.

Imidacloprid is largely banned in the European Union and is facing a proposed ban in Canada due to its severe impacts on aquatic species. Neonictinoids are also blamed for killing bees and hurting their ability to reproduce in agricultural areas where they are widely used.