The Great Lakes have been the unlucky host to many non-native species - more than any other freshwater ecosystems in the world, according to a press release from McGill University in Quebec, Canada. Without new regulations, scientists have predicted a wave of invasive species the lakes within the next 50 years, like killer shrimp.

The Dikerogammarus villosus, also known as "the killer shrimp," tears its prey apart, even when it isn't hungry, according to Science Recorder.

More than 180 non-native species have assaulted the Great Lakes and the rivers that feed into them in the last 200 years. Almost 20 percent of those have been deemed harmful both ecologically and economically. With climate change and trade in live organisms, a study from the Journal of Great Lakes Research cautions further threats to the biodiversity of the lakes and the multi-billion dollar fishery.

Shipping was bringing new species into the basin, but regulations were tightened on ballast water. Ballast water is the water ships take in and later release to keep the boat a steady weight when they receive and deliver cargo. New rules in 2006 and 2008 required ships to dump freshwater and fill up with saltwater, so that any organisms carried into the Great Lakes wouldn't be able to live (or multiply) in the freshwater of the lakes.

"No new species have been recorded since 2006," said Katie Pagnucco, PhD student at McGill and lead author of the study. "We may have closed the door on ballast water-mediated invasions. That remains to be seen. But other doors are still open."

Since live trade (the buying and selling of bait fish and aquarium pets) is unregulated, pessimists believe that there is a high risk of live animal assault on the lakes' ecosystem from the Black Sea (where Europe and Asia meet), where many disruptive animals come from, according to the press release. Particularly nasty occupiers could include killer shrimp or the monkey goby.

Climate change is also a threat as warmer climates bring southern species up, like animals from the Mississippi River Basin.

"For example, the Great Lakes have already had all the invasive species from the Mississippi that could survive there, as a temperature barrier is protecting us from others," said Pagnucco, according to the press release.