Wolf River (Fox River tributary)

Two dams on the upper Wolf River block sturgeon from returning to their historic spawning grounds at Keshena Falls on the Menominee Reservation: the Shawano Dam 125 mi. upstream from Oshkosh, Wisconsin and Balsam Row Dam 5.5 miles above the Shawano Dam, both constructed in the late 1800s. The result was that for over 100 years no sturgeon (or other fish) spawned in the waters above the Shawano Dam. Starting in 2012, the WDNR in conjunction with the Menominee tribe, implemented a sturgeon capture and relocation program to populate the river above the dams with mature sturgeon. Eggs and young fish were also used to achieve a breeding population of sturgeon in Legend Lake, a 1304 acre lake in Menominee County. Sturgeon successfully spawned at the falls the following year. The tribe has proposed that fishways be constructed around both dams to allow spawning from populations in Lake Winnebago. However, due to concerns about aquatic invasive species and Viral hemorrhagic septicemia (VHS), a deadly fish disease, the proposal has not yet been implemented, and the capture and relocation program has continued.

Zebra mussels (Dreissena polymorpha) are small, freshwater, bivalve shellfish native to the Caspian and Black Seas south of Russia and Ukraine. They can clog water intakes and pipes, encrust piers, boats and motors, and cut the feet of swimmers. Zebra mussels have been found in less than 5% of Wisconsin lakes predicted to be suitable for zebra mussels. However, they were detected in the Winnebago Pool including the Wolf River as early as 1999.

There are many different species of fish in the river. In 2016, the Wisconsin state record Quillback was caught in the Wolf River. It was 25.0 inches (64 cm) long and weighed 9 pounds 15.8 ounces (4.53 kg).[7]

The Winnebago system, including Wolf and Fox Rivers and associated lakes, is home to the largest population of Lake Sturgeon in the world. The sturgeon which spawn annually in the springtime in the Wolf River and its parent, the Fox River, between approximately April 15 and May 5, as they swim upstream from Lake Winnebago. It is estimated that the extent of the Lake Sturgeon has dropped to about one-tenth of its population in the state since year 1800. This species, which has existed since the time of the dinosaurs (100 million years ago), has a viable naturally reproducing population, which are highly prized for the taste of their flesh, and also for their eggs. Female sturgeon deposit their eggs only about every four to six years, starting at 20 years old, up to their life span of 50 years. At this age, the sturgeon are five feet long. The fish spawn in the shallows of the Wolf river, as they swim upstream.

In order to protect the spawning locations of the sturgeon from poaching when the fish are the most vulnerable, the Wisconsin Department of Natural Resources formed a citizen sturgeon guard called Sturgeon For Tomorrow in the early 1990s. They volunteer to watch over the spawning sites during the spawning season.

The walleye is very popular during their spawning period, during the spring. Many fishermen set out to catch their daily limit. The walleye is probably the most prized fish on the river.

The white bass or sand bass (Morone chrysops) is a freshwater fish of the temperate bass family Moronidae that also spawns in the Wolf River. The spring spawn typically occurs during the last two weeks of May when the female of the species is prevalent. During this time, a huge influx of fisherman (boating and shore) are attracted to the entire Wolf system. The average white bass taken from the Wolf watershed typically measures 200–300 mm (8-12 inches) in length with a maximum of about 475 mm (19 inches).[8][9] While different fishing methods and techniques are used,[10] the most common is the river rig (also known as the Wolf River rig).