Montana FWP Investigating Hundreds of Dead Fish in Madison River

According to a press release from Montana Fish, Wildlife, and Parks, FWP fisheries biologists are monitoring an area of the Madison River where a number of dead fish have been observed.

An investigation is currently underway to determine the cause of the fish mortalities. Biologists have been collecting samples from dead and dying fish and have submitted them for testing. The first dead fish were found by anglers in Beartrap Canyon on May 18.

Montana FWP staff went to the area and found several dead mountain whitefish. Since then, biologists have floated Beartrap Canyon and walked the banks of the river downstream of the Warm Springs Boat Launch each day to gather information and figure out what is killing the fish.

In an update issued at 3:00 p.m. on Thursday, May 20, FWP staff said they had observed dead fish for over 10 miles from just upstream of Ennis Dam to the Warm Springs Boat Launch on the Madison River. These include about 814 whitefish, 11 brown trout, 6 rainbow trout, and three suckers so far.

FWP staff will continue to monitor conditions on the Madison River. More information will be provided as it becomes available. If anglers see dead or dying fish, they can call the FWP Bozeman office at 577-7900.

Anglers can help reduce stress for fish by following these practices when catching and releasing fish:

• Land the fish quickly.
• Wet your hands before handling the fish.
• Keep the fish in the water as much as possible.
• Remove the hook gently. Using artificial lures with single and barbless hooks can make hook removal faster and easier. If the fish is hooked deeply, you may have to snip the line at the fish’s mouth or consider keeping it if regulations allow.
• Let the fish recover before releasing it.