If you come and visit us at the Reed Center, you will be greeted by the newest resident of our 550-gallon tank: a Northern Snakehead fish. An object of lore and legend, the Northern Snakehead is known for being a foreboding invasive species of the Chespeake Bay’s rivers. Between the ability to eat fish up to a third of their body size (which can get up to 2 feet), and their ability to survive out of water if kept moist for up to four days (due to gills that resemble primitive lungs), these fish have acquired quite a reputation.
The Snakehead Saga:
The Northern Snakehead, Channa argus, originates from China, and was first spotted in Chesapeake waters in May of 2002, in Crofton, MD. Scientists quickly noticed that snakeheads had the potential to seriously disrupt natural food web systems, because as top-level predators, snakeheads were eating anything they could fit in their mouth. Snakeheads were quickly marked as an invasive species and eradication began. MDDNR posted signs telling the public to kill any snakehead they found and to alert MDDNR.
After two years of relatively no news of the snakeheads, they showed up in the Potomac River. However, because snakeheads prefer fresher waters, it was thought that the saltier waters of the Bay would keep the snakeheads from leaving the Potomac and spreading through the Bay. Essentially, the saltier waters of the Bay were to act like a barrier, made up of intolerable waters. However, increased spring runoff caused the salinity of the Bay to decline, expanded the area that the snakeheads’ could tolerate, and opened the opportunity for them to invade other tributaries.
This past summer (2011), SERC scientists and interns found a pregnant female snakehead in the Rhode River, here at SERC. Of course it made the news, and worried scientists that there was probably more than just the one individual present in the Rhode River and similar tributaries.
What’s going on now
Snakeheads are still found in the Potomac River, and MDDNR still offers a monetary reward for catching, killing, and reporting a snakehead catch. At SERC’s Family Day this year, the Fish and Invertebrate Lab had a Northern Snakehead from the Potomac River on display in a tank. Now, we have inherited the fancy fish and are telling everyone. By having the snakehead available for the public to view at the Reed Center, you can come by and see what a real one looks like, increase awareness of Northern Snakeheads, and drum up conversations about the ecological impacts of invasive species. Plus, the fish looks pretty cool (the name alludes to the awesome patterned coloration). Stop by and check it out!
Our camouflaged companion is no longer featured at the Reed Center. The Fish and Invertebrate lab here at SERC has used the snakehead fish as part of an ongoing project to catalog all of the fish and bottom-dwelling invertebrates in the Chesapeake Bay. As part of the International Consortium for the Barcode of Life, Rob Aguilar of the Fish and Invertebrate lab has been collecting samples of fish and bottom dwellers in Chesapeake Bay. Each time a specimen is collected, a piece of DNA is sent to a genetics laboratory, where it gets recorded, sorted, and given a barcode. The project’s goal is to compile a library of DNA to help with species identification. Read more here.