Still, if you haven't been following the coverage, it can be a puzzler: All this fuss, over a fish? Just who are these marauding, cockroach-tough swimmers that have state lawmakers, the commercial fishing industry and justifiably skittish boaters in a tizzy? A primer on this fear-inducing "missile with fins":
M. Spencer Green, AP
Asian carp played a leading role in a 2006 exhibit at Chicago's Shedd Aquarium on invasive species that are threatening the Great Lakes.
"Asian carp" designates eight different major species of fish, of which only four -- grass, black, silver and bighead -- are considered invasive species in American waters. (Nor are all carp mutant-sized monsters that can grow to reach 100 pounds. The common goldfish, also known as Carassius auratus, is among the carp family too.) The fish were imported to the U.S in the 1970s to remove algae from commercial catfish ponds. Then, in the early 1990s, they rode flood waters into Mississippi waterways, and the trouble was under way.
2. They're hearty eaters.
The four common species currently in U.S. rivers will eat pretty much anything, and a lot of it -- they consume nearly half their body weight in food every day -- which can overwhelm native fish populations. Bighead and silver carps are "filter-feeders" that nosh on plankton; black carp eat mussels and snails. Silver carp don't even have stomachs, allowing them to chow pretty much all the time.
Chris Young, Keystone / AP
Asian carp stirred up a river in Utica, Illinois in 2006.
Carp have adapted to quiet lake bottoms and backwaters and are apt to jump at the sound of approaching watercraft. Jet skis and motor boats send them flying -- up to 6 feet into the air. Footage of wildly flopping, airborne carp has become fodder for viral online videos, but the fish are a genuine danger to recreational boaters: The U.S. Geological Survey has likened an encounter with a leaping carp to "being hit with a thrown bowling ball."
4. They're remarkably resilient
How to kill a carp? Not with the aforementioned poison. Nor will suffocation or starvation get the job done: Grass carp, for instance, can live under the ice of frozen-over rivers and lakes and survive on very little food; other species go into a state of "suspended animation" to make it through periods of scarce sustenance and can survive for periods of time out of the water.
Although recent reports suggest that carp might be dying off in some waterways, a comparison of carp levels from 1990 to 2000 shows how prolifically the fish, especially the bigheads, can expand their population in just a year.
(Chart: U.S. Geological Survey)
Chris Young, Keystone / AP
A new sport emerged thanks to the proliferation of asian carp.
Not everyone's upset over the Asian carp invasion, which for some innovative outdoor lovers has given rise to a new pursuit: fishing (or hunting?) for carp with a bow and arrow. Wisconsin resident Sam Woods is among them, and he likes to drive to the Illinois River to shoot the fish as they jump. "They're awesome," Woods told CBS. "If I don't put 200 fish a night in the boat, I'm pretty disgusted with myself."
jefield, Flickr Creative Commons
The futility of other Asian carp abatement efforts is prompting some, such as Illinois State Sen. Mike Jacobs, to suggest an alternate approach: If you can't beat 'em, eat 'em. Jacobs has advocated for adding carp to state prison menus, but you don't need to be locked up to dine on the fish, which is consumed widely in Asia. Illinois State University helpfully points to a few recipes -- for fried carp, and for smoked carp two ways -- and notes that some testers even preferred the taste of the fish to canned tuna.
