Commercial fishing stocks were once far larger and more diverse than at present. At one time, Green Bay supported the largest commercial fishery in Wisconsin. Herring and whitefish inhabited the shoals throughout the bay. Trout occurred in the deeper, colder waters of the northern bay. Walleyed pike, pickerel, sturgeon, suckers, bass, perch and catfish swam the shallow marshy waters at the heads of bays and mouths of rivers. This distribution began to undergo changes as early as 1850, when whitefish showed noticeable declines in parts of the bay.  Fishermen who located a large population of fish would simply fish until the stock was used up. The  Lake Herring catch peaked in 1905 and never regained its former abundance. Around 1912 the lake trout catch had also begun a slow downward trend.  The walleye catch similarly fell off while the sucker harvest began a decline in 1920.  During the peak years, thousands of pounds of fish were packed and smoked or salted to be sent to markets in the East. Hundreds of jobs were provided at the many packing houses.  Sportfishing was also popular early on. One 1856 newspaper article recounts a 2-day sport fishing    expedition to Menominee. The fishermen returned  with almost 800 lake trout, all between 20 and 30 pounds.

Whitefish Trapnetting

Some fish species were sadly undervalued. At an 1872 price of 25 cents a fish, sturgeon were hardly
worth hauling away. So fishermen stacked them on the shore like cordwood and burned them. But the sturgeon soon became valuable for its oil, caviar and air bladders --- used to produce isinglass, a gelatinous material contained in a variety of products including jams and jellies. As stocks were depleted, the sturgeon catch plummeted from over three and a half million pounds in 1880 to about 1,000 pounds in 1900. Today, a sturgeon is a rarity in the bay.

Catches of yellow perch peaked about 1900 with a harvest of 6 million pounds. 

Pollution was also an early factor in the decline of the Green Bay fishery. In 1880, a writer noted a large mass of sawdust, two miles broad and many miles long, floating about in the bay. Perch catches were on the decline after 1900.  And when, in the early 1900s, the economic focus of the region shifted from lumber cutting to papermaking, there followed fish die-offs as pulp waste reduced oxygen levels in the lower Fox River and Green Bay.

In the late 1930s, severe oxygen depletion caused by paper mill discharges of oxygen-demanding sulfite liquors (chemical residues of pulping operations) extended 18.6 miles (30 km) up the bay from the mouth of the Fox River. 

Up until the 1920s the depletion of fish stocks was a story of pollution and removal of habitat, overfishing and the vagaries of the physical environment. But another factor was added in the 1920s --- introduction of exotic species. The first troublesome newcomer was the German carp, planted throughout the state in the 1880s and 1890s. Today it is well established. Following the carp came the adaptable ocean smelt; then came invasions of the sea lamprey and the alewife through the St. Lawrence Seaway. 

Throughout the 1950s and 1960s, the fisheries could only be described as ailing. Lamprey control and introduction of salmon and trout have since given a base for sports fishing in the states bordering Lake Michigan, but most of this activity is out on Lake Michigan proper. As of 1974, lake trout were still not reproducing themselves. Both salmon and lake trout populations remain dependent on yearly restocking programs --- they are there only by the grace of state and federal revenues. Today the Green Bay commercial fishery depends largely on the harvest of alewife for fish meal and other purposes, and on the whitefish harvest in the northernmost reaches of the bay. 

More recently, the zebra mussel, spiny water flea, ruffe, white perch, and other new invaders have
introduced even more stress into the system. 

Because of pollution, overfishing and competition from exotics, several species may be out of the picture: the lake sturgeon and the deepwater ciscoes. The lake sturgeon, sometimes exceeding seven feet and 300 pounds, has been nearly exterminated. It does now receive limited protection under the Endangered and Threatened Species Act of 1973. In addition, the diversity of deepwater cisco (or chub) species that once inhabited the bay has now been essentially reduced to a single species, the bloater chub. 

In 1976, commercial catches of yellow perch sold for almost a dollar a pound and, although it wasn’t a very good year, perch from Green Bay still contributed half a million dollars to Wisconsin’s economy.  Today, the state is considering closing the yellow perch commercial and sport fishery on Green Bay due to recent severe population declines in the fish. 

(Green Bay history from Gerard Bertrand, Jean Lang, John Ross. "The Green Bay Watershed - Past/Present/Future" Institute for Environmental Studies, UW-Madison, UW-Sea Grant College Program, Technical Report #229, January 1976.)

Other Fisheries Sections:

• Introduction to Fisheries of Wisconsin and the Great Lakes