Urgent Yellowstone fishing closures hit 3 rivers as water turns deadly

Urgent Yellowstone fishing closures are being imposed on three rivers after water temperatures reached levels lethal to trout. The National Park Service announced on July 15 that the Madison, Firehole and Gibbon rivers would be temporarily closed to fishing 24 hours a day until conditions improve. Officials said peak temperatures have ranged from 80 to 86 degrees Fahrenheit during the day, with dead fish reported in the Firehole River near Old Faithful. The NPS said the closures are intended to protect native, wild trout fisheries. Research cited by the article notes trout are ectotherms, so their bodies warm with the surrounding water, making oxygen harder to obtain. The park also has additional restrictions on other waters, while Yellowstone’s angling regulations aim to maintain ecological integrity.