Aquatic Exotics In Wisconsin A Presentation Developed by Wisconsin Sea Grant Advisory Services October 2006

Aquatic Exotics In Wisconsin Wisconsin has become host to several aquatic species that never existed here naturally Some Atlantic Ocean species came in through the Welland Canal: –Lampreys, 1930’s –Alewife, 1949 –White perch, 1989 –Three-spine stickleback 1991

Aquatic Exotics In Wisconsin Some were intentionally introduced: –Chinook and Coho salmon 1963 –Rainbow trout 1963 –Brown trout 1960’s –Carp in 1880’s

Aquatic Exotics In Wisconsin Some escaped from lakes, ponds or as bait: –Smelt –Goldfish –Grass Carp –Rusty Crayfish –Purple Loosestrife

Aquatic Exotics In Wisconsin Some recent invaders came in the ballast water of sea-going ships: –Ruffe in 1986 –Zebra Mussels in 1988 –Spiny water flea in 1990 –Round goby in 1995

Invasive species traits: –High reproductive rate –Mature quickly –Eat various types of food –Tolerate poor water quality –Easily adapt to new habitats Aquatic Exotics In Wisconsin

Native species traits: –Have narrow food preferences –Require certain spawning habitat –Intolerant of poor water quality Aquatic Exotics In Wisconsin

A Quick look at six recent invaders: –Zebra mussels –Round goby –Ruffe –Purple loosestrife –Eurasian milfoil –Spiny water fleas Aquatic Exotics In Wisconsin

Zebra Mussel Max. size ~ 2’’ * Introduced via ballast water from Europe * First found in Lake St. Claire (MI) in 1988 * Eats plankton, filters up to 1 liter of water per day * Produce 40,000 eggs/year * Densities up to 700,000 per sq. meter = 43,000 on a piece of notebook paper * Spread easily via planktonic larvae and adults stuck on weeds and boats

Settle and attach to substrate Planktonic up to 1 month Zebra Mussel Life Cycle Juvenile Adult Byssal Threads 4-5 Years Egg Veliger Post Veliger 3-5 Days Can be seen Microscopic Can be felt Wisconsin Sea Grant Advisory Services

Zebra Mussels Colonize Lots of Things

Zebra mussels get moved to new lakes by water in and weeds on boats.

(24 counties, 79 lakes) Zebra Mussels 2006

Wisconsin Lakes With Zebra Mussels ? 79 Why the big jump in 2006? Better monitoring and additional infestations

Ruffe 3-4’’ Long Max. 10’’ Introduced via ballast water from Southern Europe Affects perch, whitefish and minnows Eats fish eggs, bottom-dwelling insects and worms First found in 1986 in Lake Superior Now Present in Lakes Superior, Huron and Michigan S. Zienert

Round Goby 3-4’’ Long Max. 10’’ Introduced via ballast water from Europe Affects sculpins and other bottom-dwelling species Eats fish eggs, bottom-dwelling insects and worms Present in all the Great Lakes, Chicago River

v Purple Loosestrife 4-Sided Stem Destroys Habitat v Controlled by: Physical Removal Beetles Displaces Native Vegetation 2 Million Seeds per Year

Galerucella beetles: biocontrol for purple loosestrife

Purple Loosestrife

 Eurasian Watermilfoil - Displaces native vegetation - Clogs boating and swimming areas - Spread by boaters through fragmentation  Control: Northern milfoil beetle Chemical

Eurasian milfoil compared to Northern milfoil

Eurasian Milfoil Present in: 62 counties > 475 waters

Native to southern U.S. Introduced with bait Aggressive Destroys vegetation as they feed Displaces native crayfish Present in many Wisconsin lakes Often spread as bait Rusty Crayfish

Documented Suspected

Spiny Water Flea - ‘BC’ & ‘CP’ Introduced via ballast water from Europe Foul fishing lines and nets (look fuzzy or gooey) Long spines make them hard for fish to eat Present in all the Great Lakes and Gile Flowage in WI Bythotrephes cederstroemi & Cercopagis pengoi 5mm Long Max. 1/3’’

Drain bilge water Dispose of live bait Clean off weeds Preventing The Spread

If You Catch An Aquatic Exotic KEEP It: FREEZE It: Put it in a plastic bag or foil Put it in a freezer or ice chest REPORT It: Call: Wisconsin DNR Wisconsin Sea Grant or

How Can You Help? –Learn To Identify Them –Report If You Catch One –Know Their Effects on the Ecosystem –Prevent Their Spread –Teach Others Aquatic Exotics In Wisconsin

For More Information Visit the Sea Grant Nonindigenous Species Sites: Or Call: –Wisconsin Sea Grant (920) –Wisconsin Department of Natural Resources (608)