Asian carp latest threat to Great Lakes

The latest threat to the Great Lakes ecosystem is the Asian Carp. Brought over to control algae and suspended matter from catfish ponds in the 1970's, they escaped into local waterways then into the Mississippi River basin during the floods of the 1990's. They have steadily made their way north and quickly became the most abundant fish in many areas of the river. One 22 inch fish was recently found in a fish kill in the Chicago Sanitary and Ship Canal, about 40 miles from Lake Michigan*. Their DNA has been found north of the electric barrier and only eight miles from Lake Michigan. The Asian carp prefer cool climates, similar to the climate in the Great Lakes.

While they can grow up to 4 feet and 100 pounds, the average size of the fish is 24-30 inches long and 3-10 pounds. They are quick breeders and consume vast amounts of food, up to 40% of their weight. The bighead and silver carp are filter feeders that take out the bottom of the food chain, out competing the plankton eaters. They destroy fishing nets and the silver carp jump in response to outboard motors, frequently cause bodily injury (go to http://www.youtube.com/watch?v=yS7zkTnQVaM to watch a video of carp jumping).

The Asian carp are considered a trash fish by fishermen. They are small mouthed and not tempted by baited hooks. While some consider the meat tasty, they are a bony fish. They are sold for fertilizer and human consumption overseas.

Methods to control invasives tend to be difficult, costly, and often too little and too late. The federal government will spend $13 million in a last ditch effort to prevent Asian carp from entering the Great Lakes and destroying a $7 billion fishing and tourist industry. The National Wildlife Federation is calling for the closing of the canal that connects the Mississippi River and Lake Michigan. Michigan Attorney General Mike Cox is preparing a lawsuit to close the link between the lake and the canal. While closing the canals could save the Great Lakes fishing and recreation industries, they would disrupt the movement of iron ore, coal, grain, salt, sugar, and petroleum.

*The electric barrier used to deter the Asian carp from entering Lake Michigan was turned off for maintenance and 2000 gallons of toxins were dumped into a six mile stretch of the waterway, killing 200,000 pounds of fish.