News

In order to better understand the potential for spread of invasive cordgrasses among west coast estuaries and bays, Portland State University scientists in the Center for Lakes and Reservoirs are beginning a study of ocean currents to identify coastal locations at high-risk for Spartina (cordgrass) invasion. Beginning today and then each month for the next year, 200 bright yellow drift cards will be released at the mouths of three estuaries-Willapa Bay in Washington, and Humboldt Bay and San Francisco Bay in California.

The releases will be done on an outgoing tide with the help of cooperators at the Washington Department of Fish and Wildlife, the U.S. Fish & Wildlife Service Arcata Office and the Golden Gate National Recreation Area. These estuaries have significant populations of one or more Spartina species and are potential sources of seeds or plant fragments.

The biodegradable wooden drift cards will float on the water surface and be carried by the ocean currents, behaving much as seeds or plant fragments would. The cards, made of lightweight plywood and painted with non-toxic paint, are designed to persist for only a few months in the harsh conditions of the ocean.

Observant beachgoers who find the cards should contact The Spartina Watch Project at Portland State to report where and when the cards are found. Each card has a unique identification number, a toll-free phone number and an email address for reporting purposes.

Spartina, commonly known as cordgrasses, are exotic, invasive plants in estuaries of the west coast of North America. Spartina was originally brought to the west coast for erosion control, and unintentionally in the ballast water of ships and in oyster packing material. Over the past few decades, however, scientists have recognized the threats posed by these rapidly spreading plants. Cordgrasses clog flood channels, displace native vegetation, significantly raise mudflat elevation, and degrade habitat of Dungeness crab, shorebirds and migratory waterfowl by trapping sediments in their dense stems and root-mats.

With a focus on early detection and rapid response to invasive Spartina species, Portland State scientists hope that this study will help identify areas at high risk for invasion. While large-scale populations of Spartina exist in both Washington and California, only one small population is known to currently exist within Oregon's borders. That population, located on the Siuslaw River near Florence, Oregon, is actively being treated.

The study is being funded by the San Francisco Estuary Institute (part of the Non-Chemical Alternatives Project of the Aquatic Pesticides Monitoring Program), Oregon Department of Agriculture and Washington State Department of Fish and Wildlife.

To report a drift card finding, contact The Spartina Watch Program with the card number, date found and exact location at 503-725-9767, toll-free at 1-800-880-6568 or email spartinawatch@pdx.edu.

Photos of Spartina may be viewed at www.pdx.edu/sites/www.pdx.edu.syndication/files/media_assets/Spartina1.jpg and www.pdx.edu/media/s/p/SpartinaNemahRiver.gif. The Spartina Dispersal Study Card may be viewed at www.pdx.edu/media/s/p/SpartinaCard.pdf.