Column: Alien carp launch aerial attacks

Published 3:41 am Thursday, March 30, 2006

By Staff
Imagine this, on a delightful summer day you're water skiing, the powerful boat surging you along as you cut back and forth across its wake. You make a wide swing and turn back in when all of a sudden a huge creature over four feet long and weighing some 60-pounds leaps from the water and hits you smack in the face. Your nose shatters and you tumble unconscious into the water.
Or maybe you're a fish biologist running a boat upriver. Seventy pounds of strange creature hurtles out of the water ahead. You're frozen in disbelief as you stare at the monster overhead coming directly at you. The creature catches you square in the chest and both of you crash to the hard deck. Scenes from a late night sci-fi movie? Nope. These and other like encounters are real and happened right here in the Great Lakes area.
These alien horror creatures are one of the newest threats to our waters, the Asian carp. Despite lengths over four feet long and weights topping 100-pounds, these piscatorial acrobats can leap a distance of 20-feet, reaching 10-feet high at its apex. For some unknown reason they tend to do this in the vicinity of boats. The mishaps, of course, are simply unlucky convergences; they are not attacking people or boats.
The real threat to us, though, is not physical carnage. Asian carp are plankton eaters and due to their size and voracious appetite they are mowing machines. They are also very prolific and fast growing. The fear is they may get into a major water system, multiply in great numbers and greatly reduce the plankton that so many native fish species rely on. As one expert aptly put it, this would essentially knock the entire bottom out of the food chain. In waterways such as the Great Lakes this would be devastating both environmentally and economically.
The Asian carp, of which there are four species in the U.S., were imported in the 1970s by commercial catfish farmers in the south to clean algae and other aquatic plants from their ponds. In the 1990s flooding of the Mississippi River allowed them to escape the ponds and reach the river. Two of the species in particular, silver carp and bighead carp, found the Big Miss amenable and quickly expanded north into the Missouri and Illinois Rivers. By the late 1990s they had all but taken over the Illinois River. The catch of Asian carp by commercial fishermen in the Illinois River has risen from 1,300-pounds in 1992 to recent catches of 55 TONS! It's estimated there are 1,600-pounds of Asian carp per acre of water in the Illinois River.
The scary part is the Illinois River is linked to Lake Michigan at Chicago. Asian carp are now just 50 miles from Lake Michigan, fortunately held at bay (its hoped) by an experimental electric barrier. It seems to be working but it's a tenuous hold. As Mike Conklin, chief of Illinois Fisheries, stated, “We know the Great Lakes will be very receptive to these fish. If they get in there the ball game's over for that $4 billion fishery.” Even if the barrier works there are still issues of Asian carp eggs in ship ballast water and juveniles inadvertently mixed in with bait minnows and released by unwitting fishermen. Both the bighead and silver carp reach immense proportions. Unlike common carp that have big, plate-like scales, Asian carp have tiny scales similar to trout. They also have regular shaped mouths as opposed to the sucker mouth of the common carp. The bighead's back and upper sides are dark gray grading to off white on the lower sides and belly with many irregular, dark blotches over its body. The silver carp is olive green above grading to bright silver below.
If you encounter either here in Michigan kill it very dead and immediately contact the DNR (if you caught it on a fly let me know what pattern). Carpe (not carp) diem.