By Mallory Estepp
Researchers fear that killer shrimp could invade the Great Lakes.
These freshwater crustaceans hail from the Caspian and Black seas. Over the past two decades, they made their way across Europe, and most recently were discovered in the waters of Great Britain.
Their ability to thrive in most freshwater environments and the constant trade between Europe and North America make their invasion a fearsome possibility, said Thomas Nalepa, a benthic invertebrate biologist working with the National Oceanic and Atmospheric Administration.
The species is well-named.
A killer shrimp will try to kill anything that swims by it, Nalepa said. This makes it a threat to the ecological system it invades. It doesn’t even necessarily eat what it kills–it takes one bite and moves on to its next victim.
The shrimp easily tolerate the five-to-seven day voyage across the Atlantic Ocean to the Great Lakes, Nalepa said. To avoid many potential invaders, ships are required to flush their ballast tanks with salt water to kill aquatic hitchhikers mid-voyage.
But killer shrimp and Asian carp are far from the only invasive species threatening to invade the Great Lakes.
Several potential Great Lake invaders are closely watched by the National Oceanic and Atmospheric Administration.
Rochelle Sturtevant, a regional specialist for Sea Grant, an affiliate of National Oceanic and Atmospheric Administration, recently identified 53 potential invasion threats.
This new watchlist features several fish, plants, scuds, wheel animals and shrimp. It includes the amur sleeper, water lettuce and the Caspian mud shrimp.
“There are 30 species we are committed to preventing from getting into the Great Lakes,” said Chris Dionigi, assistant director of the National Invasive Security Council.
These species are already in lakes and rivers throughout the U.S., and are detrimental to the Great Lakes health if they
Boaters who fail to wash their boats may carry invasive species from one lake to another. Photo: Wisconsin DNR
reach the lakes. And there are also several species that researchers want to prevent from moving from the Great Lakes to the Mississippi River basin.
Sea Grant is running 62 campaigns to inform the public on nuisance species. The largest is the Stop Aquatic Hitchhikers program, focusing mainly on informing jet skiers, swimmers, anglers and boaters.
A Sea Grant survey found that 23.5 percent of boaters failed to wash their boats or equipment before entering a new body of water. The main reason is that they did not know what steps to take.
However, 41 percent of boaters said they did wash their boats before moving to new waters. The rest said they never moved their boats to other bodies of water.
The National Oceanic and Atmospheric Administration runs the Great Lakes Aquatic Nonindigenous Species Information System, an online database of invasive species and information on how to prevent their spread.
Recently, the agency introduced a new search system that lists all invasive species in three categories: nonindigenous, range expanders and watchlist species. The search engine shows pictures of the species, and lists its place of origin, scientific name and family.
The program also has the option to search for species by how they became a nuisance, like bait release or pet escape.