Sign in to comment!

Fox News Weather Center

Killer Shrimp May Invade the Warming Great Lakes Waters

The killer shrimp - a shrimp that will kill prey without consuming it - has a high potential for invading the Great Lakes and its history is reminiscent of the bloody red mysid shrimp that is already swarming the relatively mild waters of the region.

The killer shrimp, scientifically known as the Dikerogrammarus villosus, is a "fierce predator and superior competitor," according to NOAA. "It's ability to eat and displace other amphipods has led to the prediction of a great reduction in amphipod diversity if introduced to a variety of North American freshwater habitats."

More than 180 invasive species have already made the Great Lakes their home, making these waters and the rivers that lead into them the most frequently and vastly invaded freshwater system, according to the Journal of Great Lakes Research.

The bloody red mysid shrimp (Hemimysis anomala), like the killer shrimp, spread successfully throughout parts of Western Europe. However, it was also observed in the Great Lakes in 2006 after it made its way overseas most likely unintentionally via ship ballast tanks, compartments that hold water, according to NOAA.

This bright red, spotted shrimp pictured above, rarely more than half an inch long, threatens the Great Lake biodiversity as it feeds off the zooplankton that are already a natural prey for many native fish species native.

And, warming surface waters of the Great Lakes are making shrimp feel even more welcomed.

"The continued warming of surface waters of the Great Lakes basin will lift thermal barriers" to invasions of species that exist in warmer waters, according to a study in the Journal of Great Lakes Research.

The red shrimp prospers in waters between 68 and 77 F, but can handle 86 F water temperatures, according to researchers at the International Association for Great Lakes Research. And, it can survive in temperatures as low as 32 F, according to the European Network on Invasive Alien Species.

Since 1995, average surface water temperatures have increased by a few degrees for Lake Superior, Michigan, Huron and Ontario, according to the Environmental Protection Agency.

These increasing water temperatures due to climate change could also enhance killer shrimp breeding if these shrimp reach the Great Lakes, according to NOAA.

An invasion of killer shrimp (Dikerogammarus villosus) could also threaten biodiversity and the fishery industry because it is an also an omnivorous predator. But, researchers have also observed cannibalistic tendencies in this species, when it feeds off newborns and weak adults. It may also kill or injure prey without consuming it, according to NOAA.

Legislation has already reduced the opportunity for species to invade the lakes. However, according to a news report from McGill University, a new wave of invasions are likely if regulations aren't enforced.

But even with regulations, this news report also said that climate change will complicate each scenario.