Visitors heading to Yellowstone National Park this summer will find some of the park's best-known fishing rivers closed due to extreme water temperatures.In a July 15 announcement, National Park Service (NPS) officials from Yellowstone said the Madison, Firehole and Gibbon rivers would be temporarily closed to fishing until further notice.The affected rivers are all located on Yellowstone's west and northwest sides, near some of the park's busiest attractions, and the Firehole River flows through the Old Faithful area.HIDDEN DANGER AT POPULAR US NATIONAL PARK FORCES TRAIL CLOSURES AS BEAR SIGHTINGS CLIMBThe closures are in effect 24 hours a day.Officials blamed unusually warm water temperatures, which can be lethal to Yellowstone's famed trout."In recent days, peak water temperatures have ranged from 80 to 86 degrees Fahrenheit during the day," the notice said.National Park Service officials said unusually warm river temperatures prompted emergency fishing closures to help protect Yellowstone's native and wild trout fisheries.
(David Madison/Getty Images)"Coupled with high air temperatures, these conditions are lethal to trout, and there have been reports of dead fish in the Firehole River."Officials added there are currently no heat-related fishing restrictions on other lakes, rivers or streams in the park.CAPTAIN HAULS IN NEARLY 500-POUND SEA GIANT AFTER GRUELING BATTLE, FEEDS MOST OF TOWNThe temporary closures will "protect the park's native and wild trout fisheries and will remain in effect until conditions improve," according to the NPS.Trout struggle to survive in exceptionally warm water because their bodies warm along with their surroundings, said Steven J.Cooke, a biology professor at Carleton University in Canada.Visitors planning to fish in Yellowstone this summer are urged to check current restrictions as warm water temperatures impact several popular rivers.
(iStock)"Fish are ectotherms, which means that their body temperature is the same as the water...