The first step to stopping invasive Asian carp is recognizing them. Here’s what every angler should know

Like enemies at the gate, invasive carp are threatening to populate the Great Lakes. Collectively known as “Asian carps,” bighead, black, grass and silver carp are notorious for outcompeting native fish and destroying habitat, including wetlands. The most imminent threat comes from grass carp, which have reproducing populations in two U.S. tributaries of Lake Erie. So far, bighead, black and silver carp remain confined to the Mississippi River. Should these fish-farm escapees become established in the Great Lakes, they would also severely damage the region’s US$556 million a year sportfishing industry by harming populations of everything from bass to muskies. Anglers can serve as the first line of defence against these aquatic invaders, however, and that starts with being able to identify them. Asian Carp Canada offers the following pointers.

BIGHEAD CARP

Voracious eaters of zooplankton, detritus and small invertebrates, these are a deep-bodied fish with a large, toothless mouth and a very large head, where the eyes are located forward and low. The top half of the fish is dark grey, while the bottom is cream-coloured with irregular dark blotches. Bighead can push five feet in length, and weigh more than 80 pounds.