Aquatic Invasive Species VOYAGEURS NATIONAL PARK AIMS TO PROTECT
INTERIOR LAKES FROM EXOTIC SPECIES AND FISH DISEASES Exotic
species such as the spiny water flea and rusty crayfish and fish
diseases are threats to the aquatic ecosystems of regional lakes
including those in Voyageurs National Park. Spiny water fleas
have recently invaded multiple lakes in the region, including
the large lakes within Voyageurs National Park. Rusty crayfish
have invaded at least one lake in Voyageurs National Park and
many lakes in the region. Viral hemorrhagic septicemia (VHS), a
fish disease, has not yet been introduced into any lakes in
Minnesota, but has caused fish kills in most of the Great Lakes
and in some inland lakes in Michigan and Wisconsin. Spiny water
fleas (PDF) are tiny (1/4-5/8") crustacean zooplankton. They are
native to Eurasia and were introduced into the Great Lakes from
the ballast water of ships. They threaten the park's aquatic
ecosystems and fishing by competing with native fish for food
and fouling fish