Invasive Plants and Animals
Many water bodies we paddle on the coast seem nearly pristine – we savor the salt air while gazing at ospreys fishing off the bow and appreciate nature’s beauty. Of course, we are used to some signs of human influence – like roads, bridges, dikes, dams and dredge spoils islands. These have noticeably changed areas or characteristics of most bays and river mouths.

A less obvious human impact has been the intentional or accidental introduction of invasive species. These are plants or animals that, after being introduced to a new area, survive and reproduce, sometimes at alarming rates, overtaking the native species and altering the ecology of a system. Invasive species are second only to habitat destruction as a cause for global loss of biodiversity. Sometimes termed “biological pollution,” invasives species don’t dissolve, dissipate or lessen their impact with time. Rather, they spread and multiply, sometimes with drastic consequences.

One of the world’s worst invaders… here in Oregon?
Many of Oregon’s estuaries are at risk of invasion by Spartina, commonly called cordgrasses - plants deemed as one of the world’s worst invasive species. Invasive Spartina grows in the mudflats and salt marshes of bays and estuaries where they can clog flood channels, displace native vegetation, significantly raise mudflat elevation, and reduce habitat of Dungeness crab, shorebirds and migratory waterfowl by trapping sediments with their dense stems and root-mats. Here on the west coast of the United States, there are four invasive, non-native cordgrasses.

Many of Oregon’s bays and river mouths are considered high risk for invasion.  But to date, Oregon has only had three very small populations of these grasses – each of which is nearly eradicated. Two of these have been on the Siuslaw River and one in Coos Bay. Catching infestations early is critical in reducing the impact on the environment as well as the time, money and effort required to eradicate non-native species like these.

In California and Washington, however, there are thousands of acres of these grasses setting seed each summer or fall. Seed can survive in wet, cold, salty conditions for periods of one year and can disperse in many different ways, including ocean currents, migratory waterfowl, ship ballast and recreational equipment like boats, kayaks or other gear. California’s largest population is in San Francisco Bay, where a rampantly growing hybrid Spartina has developed. In Humboldt Bay, one species of cordgrass, Spartina densiflora, covers 94% of the bay’s salt marsh habitat and has spread both north and south into tidal areas of the Mad and Eel River systems. And in Washington, Willapa Bay, Grays Harbor and Puget Sound are each home to one or more of these aggressively spreading grasses.

What does Spartina look like?
Each species of Spartina has somewhat different characteristics. You can see photos of each non-native cordgrass species at http://oregon.gov/ODA/PLANT/WEEDS and http://www.clr.pdx.edu/projects/ans_research/spartina/index.html. These perennial grasses range from two to eight feet tall. They grow in intertidal estuarine habitats (not in freshwater) and are typically found in large circular patches. The stems are round and cross sections are hollow between each node. Leaf blades are sharply pointed at the tips and do not have a midrib. The ligule - found where the leaf blade joins the stem - consists only of a fringe of hairs.  Flower spikes occur in late summer to fall.
Three of the four invasive Spartina species are deciduous, meaning their stems die back to the ground at the end of the growing season; the fourth stays green year-round and grows in dense tufts.

What can kayakers do to help?
Clean your kayaks and other gear
Kayaking gear could potentially spread seeds of invasive plants like Spartina as well as other invasive organisms like New Zealand Mud Snails, Chytrid fungus, Rock Snot and Whirling Disease. Sounds scary! However, there are easy to follow procedures to reduce or eliminate the risk of spreading these unwanted, destructive species. Remember to:
Drain – drain any water from your boat before leaving a water body
Dispose – wash your boat and gear at a car wash or other upland location & dispose of any plant fragments in the trash
Dry – let your gear dry out for at least 48 hours before moving it to a new water body
Visit the Stop Aquatic Hitchhikers Campaign website to learn more.

Be extra eyes in the field
Oregon Department of Agriculture and Portland State University have done numerous early detection surveys for Spartina, but more eyes in the field are always needed! People who kayak, fish or bird-watch in Oregon’s bays and estuaries have a good chance of noticing a new species and could ring the alarm if new infestations occur.

If you see a grass that you suspect could be Spartina:
• Safety permitting, take a closer look at the plant. There are many native grasses and grass-like plants in estuaries, which look somewhat similar to invasive Spartina. Closely inspect the ligule (where the leaf blade joins the stem). Does the ligule appear hairy? It may be one of these cordgrasses.
• Please note the location using either local landmarks or GPS coordinates.
• Take a photo if possible.
• Collect an entire shoot (stem & leaves).
• Call 1-866-INVADER (ODA’s toll-free reporting hotline) with your information. If you collected a sample, they will direct you where to send it.