|Invasive English Ivy at Saint Edward State Park. Lainey Piland photo.|
What is an Invasive Species?
Also called non-native species, these can be plants or animals (both aquatic and terrestrial) that invade habitats and ecosystems, where they out-compete native species for resources, damage ecosystems, and rack up millions or even billions of dollars in economic damage. Often these species have no natural predators in the ecosystems they invade, so they spread and multiply quickly, and are difficult to eradicate.
Invasive species are spread in many different ways: on clothing and hiking boots; vehicles, boat hulls, anchors, and ballast water; home aquarium water dumped into local water bodies, exotic pets that have been set loose; gardening with non-native plant species or using mulch contaminated with foreign seeds... in our globalized, on-the-go society, there are many opportunities for spreading invasive species from one area to another.
Examples of Invasive Species
One invasive species currently wreaking havoc in aquatic ecosystems across the country is the zebra mussel. These tiny bivalves create huge problems by taking over habitats and pushing out native species and causing damage to boats, underwater infrastructure, and clogging water intake/outfall pipes. This has especially been a problem in the Great Lakes, where estimated costs of managing zebra mussels and dealing with the damage they've caused is around a billion dollars. According to researchers at Washington State University, the Northwest's own Columbia River basin is among the dwindling number of major river systems not yet infected with zebra mussels. With the threat they would pose to our native species and extensive hydroelectric power generation infrastructure, it is important that these little buggers stay far away!
Some familiar plants in the Pacific Northwest are not only a pain to deal with, but are actually invasive! These include such plants as Himalayan blackberry (those thick, thorny, twisting vines that grow in ditches, roadsides, forests, parks...and whose berries make delicious pies and jam!) and English Ivy (a familiar sight in gardening and landscaping, this invasive plant shows up in unexpected natural places... if you look closely on the drive up to Snoqualmie Falls, you can see English ivy completely covering several trees in the forest alongside the road). Although these plants are ubiquitous in this area, they do threaten native species, so many cities and local conservation groups organize volunteer events to remove them from parks and natural areas.
What Can We Do?
One easy way to help with this issue is to become familiarized with which species in your area are invasive. For those of us in Washington state, the Washington Invasive Species Council is a great resource, and provides a list of the top fifty "Priority" invasive species, which you can see here. They also provide a downloadable field guide for identifying invasive species. If you see any of these species, report them!
The best thing you can do to avoid spreading invasive species is to use common sense and be conscientious. The National Invasive Species Awareness Week website offers the following tips:
Learning about invasive species and taking action on the issue is just one more way that we can work together to preserve our beautiful Pacific Northwest ecosystems. Spread the word!
- Clean hiking boots, waders, boats and trailers, off-road vehicles and other gear to stop invasive species from hitching a ride to a new location.
- Avoid dumping aquariums or live bait into waterways.
- Use forage, hay, mulch and soil that are certified as "weed free."
- Plant only non-invasive plants in your garden, and remove any known invaders. (the King Conservation District is having a Native Plant Sale this Saturday, March 1st... check it out here)
- Report new or expanded invasive species outbreaks to authorities. (See http://www.invasive.org/report.cfm for a state-by-state list of contacts.)
- Volunteer to help remove invasive species from public lands and natural areas.
- Ask your political representatives at the state, local and national level to support invasive species control efforts.
|No invasive species here! Lainey Piland photo|