Fish and Game’s Enemy No. 1: The Snakehead

Their voracious appetites, canine-like teeth and rare ability to wiggle across dry land have earned the 28 species of snakehead fish a spot on the U.S. government’s most-wanted list for wildlife, Interior Secretary Gale A. Norton said Tuesday.

She proposed designating snakeheads--which are known by a variety of derogatory nicknames, including frankenfish--as “injurious wildlife.” That would make it illegal to import them or to transport them across state lines.

“These fish are like something from a bad horror movie,” Norton said at a news conference. “These fish are top-level predators. They’ll eat virtually anything in their path.”

If they spread, she said, they could threaten scores of endangered freshwater creatures and destroy the delicate ecological balance in ponds and streams across the country. Currently, 13 states make it illegal to possess the fish, which are shaped like torpedoes and get their name from the large scales on their heads.

Snakeheads’ natural range includes parts of Africa and Asia, but scientists have found four species in seven U.S. states, including California. About 17,000 snakeheads have been legally imported over the last several years for food and as pets. Experts believe some of these fish were released into U.S. waters, either to dispose of them or to establish a local source of the fish to use as food.

In 1997, one snakehead was collected from Silverwood Lake in the San Bernardino Mountains east of Los Angeles. It was the only snakehead found in the state, according to Marshall Jones, deputy director of the Fish and Wildlife Service, an agency of the Interior Department.

The only known U.S. snakehead populations in the wild are in Maryland and Florida.

A reproducing population of bullseye snakeheads was found in Broward County, Fla., last year. This is the largest species of snakehead and can grow to be 4 feet long and weigh up to 44 pounds.

Just last month, an angler caught a smaller variety of snakehead in a pond in Maryland and showed a photo of it to state officials. So far, two adult fish and about 100 juveniles have been found in that pond. Maryland officials, worried that the fish might spread, plan to administer poison to kill every snakehead in the pond, said Eric C. Schwaab, head of Maryland’s Department of Natural Resources Fisheries Service.

If allowed to spread beyond the pond, Schwaab said, snakeheads could be extremely difficult to eradicate. They are hearty fish and multiply extremely rapidly.

Currently, snakeheads are widely available in live-food fish markets and some restaurants in Boston and New York, officials said. Since snakeheads are air breathers, they can be easily shipped via air freight, which probably has contributed to their increased availability in recent years.

The remarkable fish can live out of water for three days because it can breathe air. It eats other fish and sea creatures, birds and sometimes mammals.

Snakeheads are believed to be monogamous, and they are very protective of their young. Norton said that, according to reports from Asia, they have even attacked humans when they felt their offspring were threatened.

Officials asked for the public’s assistance in preventing the introduction of snakeheads into the country’s rivers and lakes. Anyone who wants to dispose of a snakehead should turn it over to a state fish and game official or kill it at home by putting it in the freezer.

Under no circumstances should a snakehead be released into a waterway or flushed down a toilet, Jones said.

Although Norton’s announcement Tuesday was just a proposal, she made it quite clear that she expects snakeheads to be added to the “injurious wildlife” list within a few months, after the public has had a chance to comment on it.

They will join a variety of other aquatic invaders, such as the walking catfish and foreign salmon, which are banned for fear that they could spread disease.

Norton said the snakehead’s “celebrity” had given her an opportunity to highlight the threat of invasive species to U.S. ecosystems.

Currently, some of the most threatening aquatic invaders are the mitten crab, which was discovered in San Francisco Bay in 1992 and which threatens native invertebrates, and the zebra mussel, which threatens native sea creatures by eating available food.

The zebra mussel has spread up and down the Mississippi River and into at least 20 states and two Canadian provinces. It has cost Americans millions of dollars by clogging power plant and public water intakes and pipes.

At the news conference, Schwaab was asked whether Maryland had considered bringing in a natural predator of the snakehead to take care of the problem.

“We don’t want to go down that road,” Schwaab said.