A SPECIAL REPORT: First of three parts Invasive species hurting lifestyles on the Long Beach Peninsula
By Cate Gable East Oregonian Publishing Group
Invasive species are also playing apart in the changing Long Beach Peninsula.
Dan Driscoll, owner and operator of Oysterville Seafarms, thinks pointing the finger at climate change is not entirely fair and may not be the main problem affecting oystering on the Long Beach Peninsula. Man has made other changes that he feels have had a much more direct impact on the environment of the Bay.
"Damming the Columbia River, building the jetties, clear cutting, decreasing population of native species, the japonica and other invasives in the Bay ," says Driscoll. "I don't know how we could notice global warming through all these other more dramatic changes. It's like someone complaining about a radio on an artillery range."
Driscoll feels that non-native japonica, also called eel grass or duckgrass, is the "sleeping giant in the bay."
"Japonica is narrow like angel-hair pasta and grows three to four feet long. At low tide, it mats down and can trap stickle backs and crab. Japonica is like a shag rug - it's like trying to harvest oysters under a shag rug. If you looked at it from above, I'll bet there are more Bay acres affected by japonica than spartina."
There are two species of eelgrass in Willapa Bay. The larger species (Zostera marina), which is native to Washington, grows to three feet and occurs mostly at and below mean lower water. The smaller species (Zostera japonica) was introduced in 1957 and occurs throughout the intertidal zone in areas that were previously open tideflat.
In preliminary studies conducted by University of Washington researchers, japonica eel grass, encroaching on oyster tidelands, did seem to have a detrimental effect on the feeding ability of oysters. It may cut down on the water circulation around oyster beds and curtail the ability of oysters, who are filter feeders, to get nutrients from the water.
"Our small study provides scientific evidence that oysters can be stunted by eelgrass in some places, probably because of reduced water flow and food delivery, and particularly when oysters are already stressed by low food," says Jennifer Ruesink, associate professor of biology at the University of Washington.
Longtime oysterman Larry Warnberg, too, worries about the hazards of eel grass, "If you dredge with a big dredge basket, the grass can clog the basket. It traps water and keeps water from draining. Bottom growers complain about harvesting, and japonica can slow down hand harvesting as well, although many people feel that eel grass contributes to the quality of an intact estuary. One early sign of estuary degradation is loss of submerged aquatic grasses."
Japonica, as a nonnative species of eel grass, is an invasive. These are plants or animals introduced to an ecosystem that have the ability to cause harm to the economy, environment or human health. Most invasives are brought in by humans, on boots, or the bottom of boat hulls, or are carried in from the water of another ecosystem and expelled in ships' bilge water into a bay or river.
Invasive species generally have a broader range of adaptive behavior than native species. So in times of climate change, the natives are more fragile while the invasives can take over and adapt more quickly to changing conditions.
The invasive that has received most attention lately is spartina. The mudflats of the south end of the Bay and in the Nemah River were infested with over 7,500 acres of spartina, according to the March 2006 issue of the Spartina Control News.
Many say spartina is close to being controlled. "With three more years of intensive eradication effort committed to the long-term plan, it is conceivable that the spartina will either be completely eradicated or very close to that," according to Charlie Stenvall, project leader for the Willapa Wildlife Refuge.
But as Driscoll's comment about japonica indicates, the flora of the Bay is only one of many problems that have been aggravated by changing conditions.
Brian Kemmer's family has been on the Long Beach Peninsula since the 1900s. He is a third-generation oysterman, and as an avid bird watcher notices all aspects of life on the Bay.
"The temperature of the Bay is mostly determined by the ocean water. Mud flats are the great heat exchanger. When the tide comes in over the flats, they warm up the water. Spartina inhibits the heat exchange effect of the mud flats. It tends to grow in shallower areas. Shore birds have only the higher elevations to feed on and if we get one low tide and one not so low, they get one meal a day instead of two."
Animals and creatures that can physically move and propel themselves from one place to another have a better chance of surviving climate change as they seek conditions more suitable to their needs. Plants have less adaptability in this regard as their movements must happen over time.
Kemmer noticed other changes after the long El Niño cycle that started in 1990. "We never had brown pelicans on the Peninsula before. But after the El Niños started, the pelicans started going hungry in California. Willapa Bay is a huge stopover for many migratory bird species."
The Pew Center report on estuaries spells out a dim future for coastal regions, "Potential changes in temperature and hydrologic regimes projected to occur over the next 100 years will most likely lead to loss of coastal wetlands, deterioration of water quality and disruptions in fisheries. Sea-level rise, sediment starvation, and changing species composition in coastal wetlands all threaten the sustainability and resilience of these systems."
