Restoring Pinto Abalone by Improving Hatchery Outputs and Identifying Ideal Restoration Sites

    NW CASC Fellow

  • Eileen Bates, University of Washington,
  • Faculty Advisor

  • Jacqueline Padilla-Gamiño, University of Washington,
  • WA Department of Fish and Wildlife
  • Puget Sound Restoration Fund
  • Smithsonian Institution
In Progress

In Washington, the native pinto abalone plays an important role in maintaining the health and diversity of rocky reefs and kelp beds. It is also a culturally-important species for tribes. From 1992 to 2017, the pinto abalone experienced a 97% decline in Washington waters. This sharp decline and its impact on tribes, recreational divers and ecosystem health led the Washington Department of Fish and Wildlife (WDFW) to list pinto abalone as an endangered species in Washington in 2019. WDFW and the Puget Sound Restoration Fund have been working together to use conservation aquaculture to produce genetically diverse juveniles to restore wild populations in the San Juan Archipelago since the early 2000s. 

Restoring wild populations of pinto abalone has been challenging for two main reasons: many juvenile abalone in the hatchery do not survive long enough to be transferred to their habitats in the wild, and some restoration sites see substantial mortality of abalone after they are transferred to the wild, while others have much greater success. These two challenges will only become greater as climate change continues, so it is vital that we develop an understanding of how changing water properties affect and will continue to affect this threatened species. 

The purpose of this project is to help address these two hurdles. In the hatchery, Eileen will study the possibility of using coralline algae as a substrate for larval abalone to settle on to see if it helps protect them from negative effects of climate change (such as warmer, more acidic water) and if it leads to better survival and faster growth. She will also study the biofilms (the microbes that live on the algae in the abalone tanks) to see if different microbes may be responsible for the die-offs of young abalone in the hatchery. In the field, Eileen will use oceanographic sensors to monitor the water conditions at different restoration sites and SCUBA to do surveys of the habitats (including the algae and microbes present) to determine what conditions correspond to successful and unsuccessful restoration sites. 

Using these results, Eileen will develop a manual of best hatchery practices for maximizing abalone survival and will build a model to support the selection of abalone restoration sites that will have the best chance of raising healthy populations. These resources can be used by Washington Department of Fish and Wildlife, Puget Sound Restoration Fund and other abalone restoration groups along the coast.