Greg Hitzroth, IISG’s organisms in trade outreach specialist, recently attended both the Northern Midwest Zen Nippon Airinkai Koi Club Show and the Indiana Koi and Water Garden Club Show to speak directly with water gardeners about making the right choices to prevent selecting and spreading invasive species. 
 

The overall message he shared with the attendees was that even common plants associated with water gardens can quickly become “aquatic invaders” under the right conditions. Aquatic invaders are plants and animals that cause ecologic and economic harm once established in public waterways, and removing them can be very expensive and often impossible. One way that aquatic invaders are introduced or spread into public waters is through the intentional or unintentional release of species from water gardens and koi ponds. 

 
Prevention is the best and most cost-effective way to keep aquatic invaders from spreading, and the gardeners and landscapers heard about a number of methods at the shows. 
 
The first way to keep these species from spreading is to avoid buying and using them at all. Instead, Greg recommended purchasing native species and avoiding known invasives like those on identified by Reuben Keller of Loyola University Chicago and Christa Gants and David Lodge of University or Notre Dame in their article (PDF). The Chicago Botanic Garden’s website has a list of invasive species and alternatives that are not invasive or environmentally threatening to help guide gardeners’ purchase. 
 
Additionally, simple steps like finding appropriate alternatives to releasing these species (including trading, returning them to retailers, or properly disposing of them) can have a profound effect in keeping aquatic invaders from establishing in other areas. 
 
Greg will be presenting this information at other upcoming shows and events, including this weekend’s Midwest Koi and Pond Show, and looks forward to providing information about preventing aquatic invaders to gardeners and hobbyists throughout the season. Illinois-Indiana Sea Grant is creating a number of educational materials about preventing these species from spreading, and more information about those will be posted soon.

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We are excited to offer the opportunity to propose a speaker or panel session during the 2026 Emerging Contaminants in the Environment Conference April 28-29.  The conference will feature traditional 15-minute presentations and a poster session on the latest in emerging contaminant research, policies, and outreach in the soil, water, and air.The deadline to propose a session is June 16, 2025.Learn more at the link in bio.
What Wild Things Will You Find in Your Watershed? Join us from April 22 to May 19 on iNaturalist for the Great Lakes BioBlitz! Participate in weekly challenges, view others' observations, and build community across the basin.How to Participate:-Register: Sign up on iNaturalist.-Observe: Explore your watershed and document the wildlife you find.-Engage: Share your observations and connect with fellow nature enthusiasts.
Join the Invasive Crayfish Collaborative for an exciting webinar featuring Purdue University master's student Izzy Paulsen. Izzy will share her mixed method study exploring how and why teachers use live crayfish and their interest in outreach. Her study draws from interview and survey data conducted in Great Lakes states. Register at the link in bio.
Deadline extended! 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 April 21.Learn more at the link in bio.
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