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July 29, 2002


For more information contact:
Al Ivany at 609-984-1795

The New Jersey Department of Environmental Protection's Division of Fish and Wildlife reminds aquarium enthusiasts that releasing exotic (non-native) fish species into State waters does not benefit the fish and most importantly, is detrimental to our aquatic ecosystems. In fact, according to State law, releasing any fish species or its eggs into any State water (public or private) that eventually flows into the ocean is illegal without a special permit.

"People who keep fish as a hobby must realize that for whatever reason, releasing exotic species into local waters is illegal and a serious threat to native species," said Division Director Bob McDowell.

Most fishes available for sale in pet shops are exotic and are imported mainly from Central and South America, Africa and Southeast Asia. Such fish have a hard time adjusting to a different environment and often cannot withstand the colder temperatures of our waters. Released fish often become stressed and are susceptible to parasites and other diseases. They can also become prey to native predators such as larger fish, fish-eating birds or water snakes.

In the event released fish do survive and reproduce, they can be difficult to control or eradicate. They may cause changes in the existing aquatic community through competition with native species or predation on them as well as through overcrowding and aggressive behavior. Exotic species may also affect the genetics of native species by hybridizing with them. In certain instances, species may pose a public safety threat, such as piranhas and freshwater stingrays. Released species can also carry and spread diseases that our native fish stocks are unable to fight.

The importance of not releasing exotic species into State waters takes on special significance with the recent discovery of northern snakeheads in Maryland. The snakehead, a native of China, is an aggressive predator with large teeth and has the ability to survive on land for several days. The species was first discovered in a Maryland lake last May when an angler caught one of the strange-looking fish. Since then, the presence of additional snakeheads, including juveniles (indicating successful reproduction), has been confirmed. Authorities were able to find out that someone originally released a pair of foot-long snakeheads into the lake two years ago and the resulting population now poses the significant threat of disrupting the local aquatic ecosystem.

Nationwide, snakeheads have been found in seven states and the Bush administration has announced a ban on U.S. imports of the fish. Interstate commerce will be illegal and the government is also discussing ways to help affected states destroy established populations of snakehead fish. The fish has primarily been imported as a food fish due to its excellent taste.

"The bottom line is that if you must give up your pet, be responsible and consider its well-being and potential impact on the environment," McDowell said. "Never release it into the wild."

For more information on euthanizing or placing a pet fish, visit the Division's website at