Invasive? Bloody Red Shrimp Are Supper for Great Lakes Fish
Time to rethink invasive species, at least when it comes to bloody red shrimp in the Great Lakes. In most cases, invasive species are a bad thing. They compete with native species and can really screw up an ecosystem. See zebra and quagga mussels. Bloody red shrimp can't be called friendly just yet, but research suggests they may become a new food source for native swimmers.
The findings come from researchers at Queen's University in Ontario, Canada. A study led by biology grad student Mike Yuille suggests --- for the first time --- that fish like the round goby, yellow perch and alewife have added bloody red shrimp to their diets. The work is due to be published in the Journal of Great Lakes Research.
A news release seems to refer to the goby, perch and alewife as "native species." That's true for perch and possibly true for alewives. Not so true for gobies, which are native to Eastern Europe and likely came to the Great Lakes via ballast water tanks.
Anyway ... the researchers looked at the stomach content of the three types of fish, all potential shrimp predators, and found increased nitrogen or carbon signatures in fish that frequented areas with high shrimp populations.
This suggests that the fish are eating the shrimp. Interesting, but not necessarily a reason to let shrimp populations grow. These buggers are considered a high-risk invader by some scientists.
See how they swarm.
The bloody red shrimp, aka Hemimysis anomala, likely arrived in the Great Lakes via the ballast water of ships, just like zebra and quagga mussels --- and the goby. The shrimp is a newer "invasive," discovered in Lake Michigan in 2006 and now in all the Great Lakes except for Superior.
Some folks have suggested that humans start eating a potential invader, Asian carp, which are working their way toward the Great Lakes and already populate rivers in states like Illinois. It seems that the goby, perch and alewife have adapted in a similar way. Carp, anyone?
More on Great Lakes and Invasive Species
It's Not Just Asian Carp: U.S. Identifies 40 High-Risk Species
The World's Most Lovable Invasive Species
10 Invasive Species that Changed the World Forever
Feds Hiring Unemployed for Great Lakes Cleanup