Invasive Species: Eurasian Ruffe

By Evan KreagerGreat Lakes Echo

The Nature Conservancy has named Eurasian Ruffe, a fish native to northern Europe and Asia, as one of the five “usual suspects” in the Great Lakes basin. This fish has invaded northern Lake Michigan and feeds on native fish eggs. It has sharp spines on its fins making it difficult for predators to catch and eat, giving it the nickname, “Dagger Fin.”

Eurasian Ruffe are generally just under a half a foot in length and have an olive or golden-brown color.

Invasive Species: Zebra Mussels

 

Zebra mussels are one of five aquatic invasive species that The Nature Conservancy has deemed “‘the usual suspects’ doing the most damage in the Great Lakes basin and beyond.”

Originally from Eastern Europe and western Russia, zebra mussels are the only freshwater mussels that can attach directly to other objects. They most likely have come over attached to the bottoms of ships. Once here, the mussels grow in population rapidly. Zebra mussels can produce 100,000 to 500,000 eggs per year, according to The Nature Conservancy. Nicknamed “the Silent Strangler,” these pests smother native freshwater mussels and kill plankton that some fish need to survive.

Invasive Species: Sea Lamprey

By Evan KreagerGreat Lakes Echo

The Nature Conservancy has named sea lampreys one of the five “usual suspects” invading the Great Lakes basin. These eel-looking parasites find a host and suck the life out of it. During the length of one life cycle, a sea lamprey can kill up to 40 pounds worth of fish and can grow up to 3 feet long. Sea lampreys are native to the Atlantic Ocean, Lake Ontario and the St. Lawrence River.

Tenth day of Christmas: Alewives croaking

Editor’s Note: It’s an Echo tradition to revisit one of our favorite holiday stories: Tim Campbell’s The Twelve Days of Aquatic Invasive Species Christmas. Campbell rewrote the lyrics of the holiday tune for the Wisconsin Sea Grant in 2011.  We’re publishing a new verse on each of the actual twelve days of Christmas.  
On the tenth day of Christmas, a freighter sent to me…
Ten alewives croaking — Alewives are one of the few invasive species that foul Great Lakes beaches throughout the summer. Until the introduction of Pacific salmon, alewives died off in such great numbers that tractors were required to remove them from beaches. Salmon now do a great job controlling alewife numbers, but there are still alewife die-offs due to spawning-related stresses.

Little Things, Big Problems: Spiny water flea

Last year, the Great Lakes Restoration Initiative began producing a series of educational videos about invasive species in the Great Lakes for the National Park Service. New videos are being uploaded this spring, and you can watch the entire “Little Things, Big Problems” series here on Echo. This video discusses the impact spiny water fleas have on the Great Lakes food web.