Invasive Species Facts
Current Aquatic Invasive Species in Alaska
- Atlantic salmon (Salmo salar)
- Boring sponge (Cliona thosina)
- Colonial tunicate (Didemnum vexillum)
- Golden star tunicate (Botryllus schlosseri)
- Northern pike (Esox lucius)
- Signal crayfish (Pacifastacus leniusculus)
- Violet tunicate (Botrylloides violaceus)
- Waterweed (Elodea sp.)
- Wireweed (Sargassum muticum)
Species That May Impact Alaska in the Future
- Chinese mitten crab (Eriocheir sinensis)
- Cordgrass (Spartina sp.)
- European green crab (Carcinus maenas)
- New Zealand mud snail (Potamopyrgus antipodarum)
- Pacific oyster (Crassostrea gigas)[PDF]
- Pacific transparent sea squirt (Ciona savignyi)
- Quagga mussel (Dreissena bugensis)
- Sea vase (Ciona intestinalis)
- Wakame or large brown kelp (Undaria pinnatifida)
- Zebra mussel (Dreissena polymorpha)
How Aquatic Invasive Species Get to Alaska
Below are ways in which aquatic invasive species are introduced to Alaska ecosystems.
- Aquaculture is the breeding, rearing, and harvesting of aquatic plants and animals. It can intentionally bring in foreign species for economic benefit. If contained, these plants and animals often do not represent a threat. But when plants or animals escape confinement or other species hitch a ride on these aquaculture species and then enter the aquatic environment, they can become invasive species.
- Aquarium plants and animals can become invasive when released into Alaska waters.
- If you no longer want, or can’t keep, your aquarium species please do one of the following:
- Return plants/animals to a pet shop.
- Give plants/animals to someone who is willing to take care of them.
- Take animals to a local animal control facility.
- Seal plants in plastic bags and dispose of them in the garbage.
- Any leftover live bait that is released into Alaska waters can become invasive.
- Be aware, it is illegal to release live organisms into Alaska waters and is punishable by a fine.
Boats, ships, and floatplanes
- Ballast water
- Many large vessels have ballast tanks, which are compartments that hold water used to balance the ship. Water is often taken up in one port and released in another. The water can hold live aquatic organisms that can become invasive in a new ecosystem where they are released.
- Standing water
- Any standing water on a boat, Jet Ski, trailer, floatplane, or other aquatic vessel may contain organisms that can be transferred to another body of water.
- Hull fouling
- Organisms can grow and accumulate on the hull and other submerged parts of aquatic vessels, and can be transferred to new ecosystems as the vessels move from one body of water to another.
- Plants and animals stuck in the propellers and on float rudders
- Plants and animals can easily become stuck to parts of boats, planes, trailers, and other water vessels. If you do not clean off these organisms before transporting your vessel to a new body of water, they can become invasive.
Clothing, waders, and boots
- Small plants and animals can hitch a ride on clothing and shoes from one body of water to another.
- Felt-soled waders have been determined to be particularly effective in transporting invasive species. Consequently, felt-soled wading footwear has been banned for hunting and fishing in freshwater in Alaska. Alaska’s Ban on Felt Soled Wading Footwear—FAQ, a factsheet from the Alaska Department of Fish and Game, has more information.
- All fishing gear has the potential to transfer species from one body of water to another if not cleaned after use.
Shipments of live seafood
- Both live seafood and the materials they are shipped with (seawater, moist algae, etc.) can become invasive if they escape or are improperly disposed of.
- Marine debris is any solid waste material that enters the marine environment. It is a growing global problem. Invasive species can hitchhike on marine debris from across the Pacific Ocean and wreak havoc in Alaska’s natural ecosystems.
Changing climate and range expansions
- As the oceans continue to warm, animals that were previously unable to survive in some Alaska ecosystems may now become established. They may expand their range farther north to areas they did not inhabit before. The warming oceans may also allow species transported by humans (via ballast water, ship hulls, aquariums, etc.) that previously were unable to live in the region, to survive and become invasive.
Negative Impacts of Aquatic Invasive Species
Aquatic invasive species can cause a wide variety of ecological, economic, and health issues. They can:
- Outcompete, endanger, and/or cause the extinction of native species
- Reduce or eliminate profitable recreational and commercial fisheries for native species
- Degrade ecosystems
- Create inhospitable habitats for native species
- Reduce diversity and/or productivity of native species
- Make lakes and rivers unusable by boaters and swimmers
- Damage boats and fishing gear
- Clog water pipes and increase the costs of operating drinking water facilities and power plants
- Cause human health problems
- Reduce property value of waterside homes and businesses
- Compromise safe floatplane operation by blocking taxiways, fouling rudders, or becoming entwined in wires or cables
- Cost millions of dollars in control measures and economic losses
How to Prevent the Introduction and Spread of Invasive Species
Be aware and vigilant. By understanding what invasive species are and how they get here, you can be the first line of defense against these invaders. Human actions are one of the biggest causes of invasive species. If you spend time on the water, especially in areas known to contain invasive species, make sure you inspect and clean any equipment and yourself for hitchhikers. The Alaska Department of Fish and Game strongly suggests that you follow these guidelines:
- Clean—Rinse and remove mud, sediment, and/or plant debris from all gear, boats, and boat trailers, floatplane rudders and floats, and anything that comes into contact with the water. Separate all pieces of wading footgear and waders (remove liners, etc.) to check for and remove visible mud, sediment, and/or plant debris before leaving the area. Use a stiff bristle brush to clean all fishing gear.
- Drain—Empty all water from coolers, bilge pumps, and buckets, and wring out gear before leaving the boat launch or fishing areas.
- Dry—Completely dry gear between water bodies and/or trips. Equipment that remains damp may harbor small particles of invasive species that can remain viable for weeks. If drying gear completely is not possible, decontaminate!
- Decontaminate—Freeze gear until solid or wash gear in 140°F hot water, scrubbing with a stiff bristle brush. If drying, freezing, or heating gear is not feasible, use a 2% bleach solution to clean gear away from freshwater recreation sites. Spray or rinse gear for one minute. A 2% bleach solution can be made easily by mixing 2.5 oz chlorine bleach with tap water to make 1 gallon of solution. NOTE: Bleach solutions may degrade gear made of absorbent materials. Please rinse gear on land, away from freshwater fishing areas, and dispose of disinfectants as indicated on the label.
More on deterring invasive species
- Don’t release non-native plants and animals into bodies of water.
- Don’t move contaminated gear such as pieces of docks.
- Try to avoid areas known to be infested with invasive species; for example, Whiting Harbor in Sitka, where the colonial tunicate Didemnum vexillum has been found.
- Follow the legal requirements concerning invasive species. The State of Alaska has regulations and laws to protect the environment from invasive species. Laws address things such as the type of boots/waders you can use, kinds of pets you can own, and importing plants and animals. You can learn more about these laws and regulations on the Invasive Species: Legal Requirements page at the Alaska Department of Fish and Game website.
- Educate your friends about invasive species.
- Report all sightings of invasive species.