Seagrass habitats don’t get as much attention as coral reefs or rainforests—but it’s hard to overstate their ecological importance. In the Pacific Northwest, these flowering plants, which grow submerged in shallow marine waters, provide myriad benefits, including:
Food for waterfowl
Shelter for many species of fish, crustaceans, and other animals
Storm and erosion mitigation as the seagrasses’ extensive root systems stabilize the soft ocean bottom
Better water quality, as the grasses trap fine particles and filter nutrients in runoff
Economic support because many fishery species (including salmon) spend at least part of their life cycle in seagrass communities
Carbon sequestration because an acre of seagrass can store about three times as much carbon as an acre of rainforest
In the early 2000s, eelgrass (a kind of seagrass) began to disappear throughout the San Juan Islands in Puget Sound, Washington. The loss of spawning grounds reduced the Pacific herring population. In turn, the Chinook salmon, which prey on the herring, declined. The damage continues through the marine food web: The resident killer whaled have a diet of 80 to 90% Chinook salmon.
This project will restore eelgrass in Westcott Bay by planting seeds, a promising method that is potentially less costly than the standard practice of transplanting mature eelgrass plants. Seeds have been used successfully in other areas (Chesapeake Bay, for example), but haven’t been tried widely in Puget Sound.
Our project partners will collect flowering eelgrass shoots from nearby Padilla Bay, which is home to the biggest expanse of eelgrass in the lower 48 states. The shoots will be held in flowing seawater for about 40 days while the seeds mature. Once mature, the seeds may need to be treated to make them sink quickly, so that they sink in the area targeted for restoration. Then, volunteers will broadcast the seeds on the waters of the restoration site. Divers will assess success in the spring of 2021.