They’ve electro-shocked them, bombed them with chemicals and placed them on government blacklists, but it seems that snakeheads — those long, black non-native fish that caused mass hysteria in 2002 when one turned up in a Crofton pond — never went away.

Now, state and federal officials, noting that snakeheads are thriving in the Potomac River and its tributaries, are offering anglers a chance to win a reward for catching and killing one and posting its picture on the Department of Natural Resources online Angler’s Log social fishing site.

From now until December 31, 2011, anyone who catches a Northern Snakehead with a hook-and-line and posts the catch, including a photo of the dead fish, on the log will be entered into a year-end drawing,  according to a Friday news release by the Maryland DNR, which is offering the prize as part of a joint program with the Potomac River Fisheries Commission and the U. S. Fish & Wildlife Service.

Prizes include a $200 rod and tackle package, a Maryland State Park Passport and a 2012 Potomac River Fishing license. (The park passport allows unlimited day-use entry for up to 10 people in a vehicle, unlimited boat launching at all facilities and a 10 percent discount on state-operated concessions and boat rentals, according to the release.)

Why such a drive to exterminate one of God’s creatures?

Apparently they eat pretty much anything and therefore threaten native species, such as bass, as predators and competitors. Snakeheads are tough, too, able to survive in the kind of de-oxygenated brackish water that’s becoming increasingly common in local nutrient-sodden watersheds.

(The early rap on snakeheads during the 2002 media-feeding frenzy was that they could slither over land and, basically, gobble your poodle. A 2004 movie, Snakehead Terror, takes the frankenfish idea and runs with it. The land-walking fear comes from the fact that the Northern Snakehead (Chana argus) is “an obligate airbreather,” which means that it can live in oxygen-depleted waters by gulping air at the water’s surface and survive several days out of water if kept moist.)

Why did the snakehead elicit such fear and loathing, when it squirmed onto the scene a decade ago, and find no defenders? Well, unlike other local non-native species such as the mute swan, it’s not especially pretty and has a nasty disposition.

“It’s like a striped bass crossed with a a pike shot up on steroids and drinking tequila,” says the angler in this Washington Post video.

They’re infesting the Potomac apparently, but snakeheads closer to Baltimore are not unheard – in 2002, a crabber pulled up one in the Inner Harbor that was 22 inches long.