INVASIVE SPECIES EDITION—Where we take a moment to explore the species that threaten the Great Lakes region. 
 
What was originally seen as a decorative and easy-to-maintain aquarium plant is now one of the most noxious weeds in the U.S. Sold under the name “Indian star-vine” in the late 1950s, Hydrilla verticillata was first introduced after live samples were shipped from Sri Lanka to a Florida aquarium dealer. More than half a century after careless disposal into Florida’s waterways, hydrilla can now be found throughout the south and along the east coast, with populations extending inland to the Great Lakes region. Isolated communities have also been found in Idaho and Washington.
 
This spread is not surprising since hydrilla is unusually hardy and versatile. It can grow in as little as a few inches of water or as much as 20 feet. It requires very little light to thrive and is just as happy in a nutrient-rich environment as one deprived of nutrients almost all together. It can even grow in slightly salty conditions or in water as hot as 81°F. And while it can spread through seeds, hydrilla is also able to grow from stem fragments as well as tubers that can lie dormant for up to four years. Taken together, it’s little wonder that this perennial is found on every continent except Antarctica.
 
Hydrilla’s unique biological characteristics give it a leg up over many native plants in the Great Lakes region. For example, its early sprouting season and ability to grow rapidly leaves less light for natives later in the spring, making it harder for them to grow once they begin to sprout.
 
These same characteristics also make it a nuisance to other aquatic wildlife and humans. Growing as long as 30 feet, hydrilla vines form dense mats that alter the water’s pH and oxygen levels, which in turn makes it difficult for some fish species to reproduce and grow. These mats can also impede irrigation, hinder recreation, and clog water intakes to power plants.
 
Efforts to contain hydrilla have been historically cautious out of fear that the robust plant may mutate or develop a resistance to chemical herbicides—a fear that was realized when fluridine-resistant hydrilla was found in Florida. Today the Asian hydrilla leaf mining fly, weevils, and even the invasive grass carp are used to manage hydrilla invasions. These and other methods cost states millions of dollars a year.
 
In recent years, Illinois and Indiana have banned the sale, barter, and transport of hydrilla. Water gardeners, aquarium hobbyists, and others can learn how to recognize the plant—and distinguish it from the invasive Brazilian elodea—with our species WATCH card.
 
We’ll have more species spotlights on aquatic invaders throughout May in honor of Illinois Invasive Species Awareness Week. 

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Don't miss out on the latest edition of our "Making Waves in Education" newsletter! Reserve your spot for a live, Students Ask Scientists call from Lake Superior, and stay updated on upcoming in-person events to learn and network with fellow educators. Perfect for Illinois and Indiana educators passionate about the Great Lakes and environmental education.
Join us on June 6-7 at the Indiana State Fairgrounds to explore aquaculture business management at the NCRAC Aquaculture Business Short Course! Presented by Sea Grant & @purdueextension, this course provides essential skills for effective farm finance management. Don’t miss this opportunity to enhance your expertise in aquaculture!Important Info:-Hands-on training to help aquaculture producers manage their farm finances-Includes one-on-one expert time + free $120 textbook-Instructors from Purdue, Mississippi State, and University of Maryland-Laptop + farm financials required for participation-Limited seating – first come, first served!More info at the link in bio.
May is National Water Safety Month—and Lake Michigan deserves your attention. Its waves may look calm, but dangerous currents and sudden drop-offs make it the most hazardous Great Lake for drownings.This May, we’re encouraging everyone to take a moment to get informed. Check out our brochures, safety tips, and the new Lake Michigan water safety video before heading out to the beach or boat.Full story at the link in bio.
Join the Invasive Crayfish Collaborative for an exciting webinar featuring educator and author Rick Reynolds. Rick will demonstrate how to engage grade 2-12 students using the newly developed science curriculum "Investigating Crayfish and Freshwater Ecosystems". Rick will share STEAM activities, including scientific investigations and simulations. Participants will also gain the tools and confidence to participate in the Invasive Crayfish Collaborative’s crayfish study- supporting ongoing research and conservation efforts. Register for the webinar at the link in bio.
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