Montana man fishing Yellowstone River with sons battles 117-pound giant last seen 22 years ago: ‘The biologist said ‘wow’ right away’

A Montana father fishing with his two sons pulled a 117-pound paddlefish from the Yellowstone River in June, only to discover the enormous fish had been tagged 22 years earlier in North Dakota. Trevor Swisse caught the fish June 12 at Montana’s Seven Sisters Wildlife Management Area near Sidney, according to reports citing Montana Fish, Wildlife & Parks (FWP).

Swisse was fishing with his sons, Mason, 15, and Charles, 6, when he hooked the paddlefish in slack water behind a sandbar. Swisse initially thought he had hooked a much smaller fish.

He told FWP that he cast into the slack water and hooked the fish almost immediately. It came toward shore easily, but he could not see its size until he got over the riverbank.

Wildlife officials noticed something important.

According to Montana FWP, Swisse’s catch was officially verified as the largest paddlefish harvested in Montana for the entire 2026 season. Swisse’s catch, however, became even more significant when Swisse and wildlife officials noticed a metal jaw tag on the fish. “The biologist said ‘wow’ right away,” Swisse told the Bozeman Daily Chronicle.

The tag identified the paddlefish as ND7570, a fish North Dakota Fish and Game had captured and tagged on April 27, 2004, during a research effort on the Missouri River near Williston. At that time, the fish weighed 90 pounds and measured 49 inches from the fork of its tail to its eye.

Researchers used the tagging program to collect information about paddlefish populations, growth, and harvest rates. After North Dakota officials tagged ND7570, they released it back into the river. Twenty-two years later, Swisse’s catch gave biologists another set of measurements from the same fish.

At the Intake Dam Fishing Access Site cleaning station, officials recorded the fish at 117 pounds and 52 inches. That means the paddlefish had gained 27 pounds and added 3 inches to its measured length since 2004.

The fish’s journey fits the known movements of the Yellowstone-Sakakawea paddlefish population.

According to the North Dakota Game and Fish Department, mature paddlefish migrate upstream from Lake Sakakawea into the Yellowstone and Missouri rivers to spawn. Most spawn in the lower Yellowstone River before returning downstream to Lake Sakakawea. 

Montana FWP also documents movement between the Yellowstone and Missouri rivers. Its paddlefish management plan says fish tagged and released below Fort Peck Reservoir have been recaptured at Intake on the Yellowstone River, and fish tagged at Intake have been recaptured below Fort Peck. The agency says considerable mixing occurs between the areas.

The fish’s exact age remains uncertain. FWP regional fisheries manager Mike Backes estimated that the paddlefish could be at least 40 to 42 years old. Researchers planned to examine a section of the fish’s lower jaw to determine its age more precisely.

At 117 pounds, Swisse’s paddlefish ranked among Montana’s largest catches in 2026, although it did not break the state’s record. Montana’s paddlefish record stands at 142.5 pounds, according to published records cited in reports about the catch.