Year one of a multi-year walleye tagging study on the Missouri River and Lake Oahe is complete, and returns are providing biologists with valuable information.
Scott Gangl, North Dakota Game and Fish Department fisheries management section leader, said more than 9,100 fish were tagged in 2013, the first year of the four-year study, and nearly 1,400 tag numbers were turned in by anglers.
The study area extends from the Garrison Dam in central North Dakota downstream to Oahe Dam in South Dakota, and involves a major collaboration of biologists and researchers from North Dakota Game and Fish, South Dakota Game, Fish and Parks, and South Dakota State University.
The study is designed to assess walleye movements, mortality and what proportion of the walleye population is harvested annually by anglers.
Gangl said the first year of the study revealed some interesting movement patterns. For example, fish tagged in North Dakota moved greater distances than those tagged farther downstream. In North Dakota, fish tagged in both Oahe and the Garrison Reach of the Missouri River traveled an average of 40 river miles. Fish tagged in Lake Oahe’s upper and middle zones within South Dakota moved an average of 10-15 river miles, and those tagged in the lower zone moved only about 5 miles. North Dakota fish moved both upstream and downstream after tagging.
Gangl said most of the returns were from May, June and July, and when the bite slowed in August, so did the returns.
The goal of the four-year study is to tag 10,000 walleye in the study area in the Dakotas per year, Gangl said, with up to 4,000 tagged and released annually in the Missouri River and upper Lake Oahe in North Dakota.
The study targets adult walleye, each fitted with a metal jaw tag stamped with a unique number to identify the fish, and a phone number to report the tag. Anglers can either keep or release the fish. Anglers practicing catch-and-release can write the tag number down and report it, leaving the tag on the fish when released.
Anglers can report tags by calling the phone number found on tags, which, anglers should note, is a South Dakota phone number. Tag information can also be reported on the Game and Fish Department’s website, gf.nd.gov, tag reporting page or by calling 701-328-6300.
Anglers should record the date and location of the catch, whether the fish was kept or released, tag number and length and weight (if the fish was measured). Anglers who report tagged fish can keep the tag, and will receive a letter providing some history on the fish.
Gangl said a small portion of the tags offer a reward to anglers to encourage them to turn them in. These tags clearly marked “Reward.”
Reward tags must be physically turned in to Game and Fish offices in Riverdale or Bismarck, or to a Game, Fish and Parks office in South Dakota.