Walk on most any beach in Grays Harbor, Willapa Bay or Puget Sound at this time of year and you will see green blades of eelgrass, the red raspy-textured Turkish Towel or the pinkish narrow branches of Succulent Seaweed washed ashore at the tide line. It is winter, and many seaweeds are perennials that senesce, or die back, leaving only root structures to survive the winter.
A submerged aquatic hero
Eelgrass is one of these seaweeds, and the extraordinary hero of the nearshore tidelands. Eelgrass is common in tidelands and shallow waters from Alaska to Baja. It lives in soft-sediment habitats and can reproduce through seeds and expand through below-ground rhizomes. It can form huge dense meadows that play critical ecological and economic functions by providing habitat for herring, crab, shrimp, shellfish, juvenile salmon and waterfowl. Eelgrass meadows exhibit high species abundance and diversity.
…even as seaweeds have inherent value for habitat and as economic commodities they may be in decline
A formidable multitasker
Eelgrass protects the coastline using its extensive root systems to prevent shoreline sediments from washing away during storms. Eelgrass mitigates climate change by absorbing carbon dioxide and methane gases. This can help reduce ocean acidification and help oysters and Dungeness crabs with shell production.
Eelgrass provides habitat and shelter for microorganisms, plankton, and forage fish like herring. It feeds birds like Pacific Black Brant. Eelgrass improves water quality by absorbing pollutants and trapping sediment. And, finally, eelgrass strengthens coastal economies by supporting tribal, commercial and recreational fishing, shellfish harvesting and as well as a wide array of wildlife that draws tens of thousands of visitors every year to coastal areas.
A Salish and First Nations saying tells us “when the tide is out, the table is set.” Seaweeds and kelp are on this table, and important to other cultural traditions as well. Eelgrass rhizomes and leaf bases and eelgrass with herring spawn attached are two noted delicacies.
Establishing protections for eelgrass
In 1980, an 8,000-acre eelgrass meadow was protected from industrial development by the creation of the Padilla Bay National Estuarine Research Reserve (NERR) located near the town of Bay View, in Skagit County. There are 29 NERRs located in sensitive coastal areas around the US. The goal for each NERR is to provide public education, monitoring, stewardship, research and training. Padilla Bay is managed by the Washington State Department of Ecology and NOAA.
In 1993, our legislature established new protections for seaweeds, recognizing that even as seaweeds have inherent value for habitat and as economic commodities they may be in decline. As a result, commercial harvest of seaweed was prohibited on public and private tidelands in Washington state except for the harvest of Macrocystis for the herring roe market. Personal harvest of up to 10 pounds per day are allowed with the proper license.
Scientists at the Puget Sound Partnership use eelgrass as one of 25 indicators of ecosystem health. Changes in the number of acres of eelgrass habitat are as a metric of overall health of native seagrass beds in Puget Sound. The target for recovery is a 20% increase relative to the 2000-2008 baseline by this year, 2020.
Threats to eelgrass remain
In Willapa Bay, Grays Harbor and Puget Sound there are native and non-native (japonica) species of eelgrass, the latter thought to have been introduced from Japan when the Pacific Oyster was shipped here for cultivation. The Padilla Bay NERR protects the non-native as well as the native eelgrass because both serve similar ecosystem functions, and the non-native appears to have no negative ecological impacts.
Japonica was listed as a protected species by the Department of Fish and Wildlife until 2011 when it was declared a Class C noxious weed by the State Noxious Weed Board. Japonica’s dense root system can impede harvesting of manila clams in Willapa Bay. As a result of the noxious weed determination the Department of Ecology allows the herbicide imazamox to be sprayed on commercial manila clam bed farms to eradicate japonica. Herbicides are not currently sprayed on eelgrass beds in Puget Sound.
Worldwide there has been a 30% reduction in eelgrass since 1870 from human-based pollution, dredging, sedimentation, aquaculture and development and from climate disruption, which is raising air and water temperatures and sea levels. In Puget Sound current monitoring indicates that the eelgrass population is stable, there are local declines due to a variety of factors.
Neglect back home at the Twin Harbors
What about eelgrass in the Twin Harbors of Willapa Bay and Grays Harbor? The DNR monitors eelgrass beds in Puget Sound, but not Willapa Bay and Grays Harbor. The Puget Sound Partnership uses eelgrass as a vital sign for Puget Sound restoration, yet there is no restoration plan for the Twin Harbors, no vital signs and certainly no NER Reserve to protect eelgrass meadows. In fact, it is even hard to know where eelgrass thrives since there have been no long-term monitoring studies to understand changes in this critical habitat. There is much at stake. The Ports of Grays Harbor and Willapa have a significant commercial fishery and shellfish industry that depend upon vital eelgrass ecosystem functions to nurture crabs, oysters, salmon and other commercial species. There is significant tourism generated by shore bird festivals and visits to the Willapa National Wildlife Refuge. Without eelgrass, there will be no birds, no fisheries, no sustainable aquaculture.
The first step is noticing
On your next walk on the beach, look for eelgrass on the tidelands or tide line. Can you see the tiny crabs? Small fish? Do you see why it is called a meadow? The first step to solving the challenges facing eelgrass is awareness. If we don’t know where eelgrass is and we don’t monitor it extensively, as in Puget Sound, how will we begin to understand and value the long-term impacts of this aquatic hero?
Sue Joerger is Policy Director of Twin Harbors Waterkeeper.
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