Capable of reaching upwards of three feet in length, plecostomus are covered with thick body armor as well as a plethora of spike-like spines along and within the fins. They destroy natural habitat by sucking up algae - that some indigenous species feed on -fish eggs and larvae. They also burrow into river banks causing unstable ground and the release of sediments into the water. Because nothing in the United States will eat them, it's up to man to try and control them (hell, it was man that put them there in the first place). Problem is that sucker fish don't respond to anything an angler might throw at them, they're generally too deep to shock, and traps and nets have proved to be a waste of time. The only way to really make a dent in the population is to take them on one at a time, mano on fish-o.