INVASIVE SPECIES EDITION—Where we take a moment to explore the species that threaten the Great Lakes region.

 

They may not be what comes to mind when you think of invasive carp, but grass carp can have drastic and lasting impacts on aquatic ecosystems and water quality. Originally from eastern Asia, they have been introduced the world over as a biocontrol for aquatic weeds and can now be found in over 70 countries. 

This wide range is made possible by their versatility—not unlike the hydrilla they are sometimes employed to eliminate. Grass carp can live in water temperatures from below freezing to over 100ºF, can survive in brackish waters, and are able to tolerate low-oxygen environments. 

 
While they live mostly in slow moving and still waters, eggs are spawned in fast rivers, and must remain suspended for two to four days before they hatch. From there, grass carp grow quickly—as much as 10 inches in the first three months. An adult can grow to be upwards of 4 feet in length and more than 50 pounds on a diet of mostly aquatic weeds. But they have also been known to consume detritus, insects, and other invertebrates as well.  
 
Grass carp were first brought to the U.S. in 1963 when they were imported from Malaysia and Thailand to aquaculture facilities in Alabama and Arkansas. Their first release into the wild is believed to have happened three years later when some escaped from the U.S. Fish and Wildlife Service Fish Farming Experimental Station in Stuttgart, Arkansas. Planned introductions began in 1969 in an effort to control nuisance plants. By the end of the 1970s, grass carp had been introduced in 40 states. Today it can be found in 45 states, with well-established populations throughout the Mississippi River Basin.
 
Grass carp are a highly regulated species, and for good reason. Because they are so adept at consuming plants, there is a risk that these veritable aquatic lawnmowers might leave a waterbody completely devoid of plant life and wipe out the food supply for other fish, insects, and waterfowl. A lack of plant life can also spur on algal blooms, which in turn lower oxygen levels. And without roots to keep sediment secure, the water is likely to become muddied, and spawning beds for other fish can be destroyed. 
 
Because of these and other risks, grass carp used for weed control are sterilized by shocking the eggs with drastic changes in either temperature or pressure. But this process is not 100 percent effective, and fish sometimes escape into the wild. In some states, including Illinois, the use of grass carp is restricted to private ponds or pools. Those thinking about using the fish for personal use are encouraged to explore other weed-control options.  
 
 

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Today is the last day to submit your bracket for this year’s Rain Garden Rumble! It’s our favorite time of the year...Rain Garden Rumble!This will be our 6th annual competition where 28 native plant species go head-to-head (or bloom-to-bloom?) in a fierce competition. But the best part? YOU determine who is crowned champion.There are a few ways to participate. First, fill out a bracket* (steps below). Then, vote in our daily Instagram polls or Facebook posts from March 18th through April 4th. The person who submits the most accurate bracket wins a sweet set of Illinois Extension "rain-care" merch (an umbrella and rain gauge)!👀*You do NOT have to fill out a bracket to vote in the polls!1. Click the link in our bio to open our official blog with more information regarding the event.2. Scroll down and click our bracket.3. In the tab that pops up, click the “download” icon.4. Fill it out with your picks and save the document. Please include your name! Note that you can learn more about the plants by clicking their names in the bracket.5. Submit your completed bracket to RedOakRainGarden@illinois.edu by Monday, March 17. Matches begin the following day on Facebook and Instagram.May the best plant win...🌿🏆#RainGardenRumble2025
Applications are open! Graduate student applicants can request up to $10,000 to support research expenses, graduate student stipends, travel, or other activities that help expand the scholarly or societal impact of their research.One of IISG’s long-term goals is to help build a community of researchers and outreach professionals focused on critically important Lake Michigan issues. The IISG Scholars programs are designed to help build this community by introducing researchers to the issues and the individuals, organizations, and communities that are affected by them.Applications due April 9th.Learn more about this opportunity at the link in bio.
The IISG program, in cooperation with the @nationalparkservice at @indianadunesnps and @UrbanRivers in Chicago, is offering two internship opportunities to support conservation policy efforts. Sea Grant’s national Community Engaged Internship (CEI) program aims to broaden participation in coastal, ocean, Great Lakes, and marine sciences providing training and mentorship to the next generation of scientists, decision-makers, and citizens. The program will do so by recruiting, retaining and engaging students in place-based research, extension, education, and/or communication that respects and integrates local ways of knowing.Applications due March 17.Learn more at the link in bio.
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