At 50 pounds, the Asian carp can pack up a punch–especially if you get caught in a cloud of jumping fish. “The air is so thick with fish that some bash together mid-flight, showering everyone with a snot-like splatter,” writes Ben Paynter in a Bloomberg Businessweek feature on the invasive Asian carp.
Damaged boats and injured boaters—broken noses and concussions are among the alleged crimes of the Asian carp—aren’t even the biggest problems with the fish. The bottom-dwellers eat voraciously, starving the native fish and quickly outgrowing any natural predators. They’re now in 23 states, and fears are that they will soon invade the Great Lakes.
Drastic policies to protect the Great Lakes, such as completely rerouting the trade through Chicago’s waterways, have made it as far as the Supreme Court even though tracking the fish’s actual location is rather imprecise. (The Supreme Court rejected the request.) eDNA—e for “environmental”—detects the presence of DNA from Asian carp but it can’t tell the difference between 1 and 100 fish or even between a live fish or a few scales. Instead, writes Paynter, researchers have resorted to brute force methods for counting fish in a river: electrocution and poison.