Illinois river otters are just one of the susceptible organisms in the local environment, and a recent study is showing that they are indicating some very high levels of dangerous toxins (including a banned insecticide). 
 
“‘Thus otters serve as biomonitors – organisms that contain information on the quantitative and qualitative aspects of the environment – of wildlife exposure,’ according to a new study. They also serve as biomonitors for human health because the same toxic chemicals found in otters have also been found in people who eat contaminated fish.
 
The study published in the journal ‘Ecotoxicology and Environmental Safety’ found high concentrations of chemical compounds in the livers of 23 otters in central Illinois.
 
Especially troubling were the highest concentrations of dieldrin ever reported in otters anywhere in the United States, said lead author Samantha Carpenter, a wildlife technical assistant at the University of Illinois, Urbana-Champaign.
 
Dieldrin is one of the organochlorine insecticides banned in 1978. More than three decades later, high levels of the chemicals remain in river sediments and accumulate in the fish that otters and people may eat.
 
The compound has been linked to neurological, behavioral and immune-suppression problems in wildlife. Scientific studies disagree on adverse human effects, but some studies have linked dieldrin to asthma, Parkinson’s disease, Alzheimer’s disease and breast cancer, Carpenter said.”
Read the complete article at the link above.

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Celebrate Earth Day with freshwater science and good conversation! Join Illinois-Indiana Sea Grant, the Northwestern Center for Water, Loyola University researcher Tim Hoellein, and IISG’s Sarah Zack for Science Sips: Trash Talk about Chicago Waterways. Learn what research reveals about litter and trash in Lake Michigan and Chicago waterways and what we can do to help.Plus, enjoy Great Lakes trivia games!📅 April 22, 2026⏰ 7–9 PM📍 Sketchbook Brewing Company, Evanston Tap RoomCome curious and ready to test your Great Lakes knowledge!
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Coastal protection is not limited to concrete, rocks, and steel. Coastal protection solutions exist on a spectrum, ranging from softer “green” solutions to harder “gray” structures.Nature-based coastal solutions fall between green and gray techniques, providing multiple benefits to people and habitats.Our three-part video series, Nature-Based Coastal Solutions in the Great Lakes, is now available to watch. Learn how nature-based coastal solutions, including nature-driven and hybrid approaches, can protect shorelines while supporting ecosystems and communities.Watch the 3-part video series at the link in bio.(Photo credit: Liz Spitzer, Illinois State Geological Survey, Coastal Research Group)