Posted on April 30, 2013
In the 1970’s/1980’s some humans decided to introduce Blue Catfish into three Virginia Rivers in the Chesapeake Bay region. The bright idea: start a new recreational fishery. The Blue Catfish is a very large [100 lb.] freshwater creature native to the Mississippi, Missouri, and Ohio rivers. The bright idea–like many other wildlife introductions—was a bad idea.
Since the 1970’s/1980’s, Blue Catfish have spread into many other rivers in the Chesapeake Bay region. Now, they inhabit most major rivers in Virginia and Maryland that flow into the Bay. And they have even adapted to the Bay’s brackish waters (waters that contain a mix of fresh water and salt water). In addition, they have been increasing in numbers at rapid rates.
Today Blue Catfish are highly abundant. To give you an idea of just how abundant – Scientists have caught upwards of 6,000 Blue Catfish in one hour while conducting population surveys! The catch rates for Blue Catfish are ten times higher than catches rates for any other species in the region. And in some rivers scientists estimate they make up 75% of total fish abundance.
The problem? The Chesapeake Bay system and its species were not designed to deal with Blue Catfish. Scientists now believe that the high abundance of Blue Catfish is negatively affecting many of the region’s native species. Blue Catfish are causing harm because they are top-predators that consume large quantities of many different species – including important Bay species like blue crabs, American shad, menhaden, and herring. [In contrast there are very few species that eat Blue Catfish.] They may also out-compete native fish for food.
Managers have declared Blue Catfish an ‘invasive species’ – a species that lives in an environment where it doesn’t naturally belong and likely causes harm to the ecosystem.
To fix the problem, fisheries scientists and managers are trying to educate the public about Blue Catfish to help prevent further introductions into other areas. And they are developing strategies to reduce Blue Catfish abundance. One strategy is to increase fishing for Blue Catfish. Some commercial and recreational fishermen already catch Blue Catfish. However, scientists and managers say we need to catch even more [something we do not often hear]. In other words, Blue Catfish is one species we should catch and eat!
So if you are looking for a sustainable seafood option, give this species a try. Blue Ocean Institute has rated Blue Catfish ‘green’. And, when available, our partner Whole Foods Market will sell Blue Catfish in their stores. [One warning- You should not eat too many large Blue Catfish because they can contain high levels of PCBs. In Virginia, fishermen are not allowed to retain most large Blue Catfish because of these health concerns.]
Rather than continuing to catch and eat depleted tunas, groupers, and cod, which hurts our environment – Perhaps it is time to catch and eat more overly-abundant invasive species, like the Blue Catfish. Then we can have our seafood AND help our environment at the same time!
Elizabeth Brown is a research scientist at Blue Ocean Institute.