DNR: Waterflea infestation triggers changes on border

In response to the spread of non-native, invasive spiny waterflea to U.S.-Canada border waters, the Minnesota Department of Natural Resources has implemented new regulations on Rainy Lake, Namakan Lake, Rainy River and Lake of the Woods.
The regulations are intended to prevent the spread of spiny waterfleas to other waters.
They prohibit the transport of water, prohibit harvest of bait for personal use, and restrict the commercial harvest of bait from those waters, similar to zebra mussel-infested waters in Minnesota. Commercial harvest of bait will still be allowed at Lake of the Woods and the Rainy River by licensed minnow dealers who have received special training and permits.
"Spiny waterfleas can spread when boats, fishing or bait harvesting gear, or even seaplanes become contaminated with egg-laden females or when water from the infested lakes and rivers is transported," said Gary Montz, DNR aquatic invertebrate biologist. “Although the waterfleas may die between fishing trips, they might be carrying resting eggs that can begin a new infestation.”
Experts believe spiny waterfleas originally arrived in the United States from Eurasia in the ballast water of cargo ships. They were first found in Lake Ontario in 1982 and in Lake Superior in 1987. Boaters, anglers and seaplanes have most likely spread them to inland waters since then.
DNR recently designated the four waters as “infested waters” because spiny waterfleas are documented in those waters, or in the case of the Rainy River and Lake of the Woods, the waterfleas will be carried in water flowing downstream into them.
Crane Lake, also in the Canadian border region of the state, was recently confirmed to contain waterfleas. Kabetogama and Sand Point lakes are also likely to have them since they are directly connected to Crane Lake. Designation of these waters, and possibly other adjacent waters, as infested will follow.
Spiny waterfleas collect in masses, sticking to fishing lines, downrigger cables and anchor lines. The masses can resemble gelatin or cotton batting with tiny black spots, which are the creatures' eyes or eggs. Individual animals are difficult to distinguish without magnification because they are only one quarter to five-eighths of an inch long.
Anglers are often the first to discover spiny waterfleas because the fleas adhere to angling gear. The waterfleas can be a nuisance to anglers. Where there are high densities of the waterfleas, they can foul up angling gear.
The waterfleas can have different harmful impacts in different lakes. The waterfleas compete with small fish for food called zooplankton. While larger fish eat them, tiny fish may not be able to consume this invader. In certain types of lakes, waterfleas can change the species and numbers of zooplankton, which can harm those lake ecosystems.
To combat the spread of the spiny waterfleas and other aquatic invasive species, the DNR,  Voyageurs National Park, and others will step up public information efforts with the message to “Stop Aquatic Hitchhikers!” Signs will be posted at water accesses, watercraft will be inspected at water accesses, and brochures and identification cards will be distributed to boaters and anglers to inform them how to prevent the spread.
Before leaving the water access, boaters and anglers should:
• Remove aquatic plants and animals, including gelatinous or cotton-batting-like material from fishing lines, downrigger cables or anchor ropes.
• Drain water from livewells, bait containers and bilges by removing the drain plugs; those who want to keep live bait must replace lake or river water with tap or spring water.
Boaters and anglers should also:
• Dispose of unwanted live bait in the trash.
• Spray the watercraft and gear with hot high pressure or hot tap water (above140 degrees F or 60 degrees C for at least one minute) before transporting to another water or dry the watercraft and gear thoroughly for at least five days before transporting to another water.
The National Park Service will take precautions to help prevent the spiny waterflea from invading the Voyageurs National Park’s interior lake systems.
More information may be obtained at DNR Fisheries offices in Baudette or International Falls. Spiny waterflea watch identification cards are available by calling the DNR Information Center at  (651) 296-6157 or 1-888-MINNDNR.