February 9, 2018
Among the oldest species of fish known, Wisconsin is home to the larger share of the sturgeon, with Lake Winnebago holding the largest number of Lake Sturgeons in North America. The species is today a valuable source of income for the commercial fishers, with its products, caviar, and meat being of high-quality value with markets in the United States and the world in large. However, just like any other species, it has been dwindling in numbers and needs to be protected lest it goes into extinction. My family likes to participate in Sturgeon Fest held downtown Milwaukee each year hand releasing a baby sturgeon into Lake Michigan. Sturgeon Fest is an amazing organization run by River Edge Nature Center, which is in close proximity of our family north of Milwaukee.
The Sturgeons have fossil records dating back to about 150 million years ago. According to the Southern Regional Aquaculture Center, the Sturgeon’s cylindrical shape, its scutes, and top elongated tail fins distinguish it from the rest of the species. Also, their scaleless bodies that are spindle-shaped become more rounded as the fish progress with time. Wisconsin is known for harboring two species of this kind, the Shovelnose Sturgeon and the Lake Sturgeon (Robins et al.). Though these species have significant similarities, they also have significant differences. Let’s take a look:
The Lake Sturgeon
The young lake sturgeon are gray dorsally, with dusky dorsal and lateral botches. The adults are gray dorsally and white ventrally (Becker 1983). It is mostly found in Lake Michigan and Lake Superior drainage basins. It thrives in large lakes and rivers, living in the deepest mid-river areas in the inland (Enblon 6-8). The sturgeon begin their spawning migration in May, with the spawning taking place over late April and early in March, in the St. Croix River (Eddy and Underhill, 99).This may vary during some seasons, but it is a rare occurrence.
The Shovelnose Sturgeon
It has a body more elongated than that of the Lake Sturgeon, with the upper lobe of tail elongated into a threadlike extension. The adults are gray dorsally and lighter ventrally (Becker 1983). It is only found in the Mississippi drainage basin, though it is already depleted in Alabama and South Dakota. They spawn during early May and June in Red cedar Chippewa Rivers (Miller 87-102). They swim up to the St. Croix as the Lake Sturgeon, where the conditions best suit the spawning.
Protection of the Wisconsin Sturgeon
From the ancient times, the sturgeon was an enemy of the commercial fishermen. They were considered a nuance, with instances of the fish breaking the nets of the fishermen, so that the fishermen disregarded them and threw them away (Becker 1983). Over time, however, the value of these species has gone up, with there being markets for their caviar and meat (Van Eenennaam, Chapman and Jarvis 277-311). With the threat of extinction, measures are being taken to protect those that are still remaining as well as help them reproduce.
The Sturgeon species live long, and due to this, it takes longer for them to mature, and they further spawn only once every 2-5 years (Mims et al. 2-6). Sturgeon has been added to the Appendix II list of the United Nation’s Convention on International Trade of Endangered Species of Wild Fauna and Flora (CITES), restricting importation or exportation of the species without a permit. For Wisconsin, they are calling for the ‘reestablishment of the species in their original range, where natural production would develop self-sustaining populations. In the Upper Flambeau, for example, efforts to collect and spawn fish from North Fork are undergoing (LeBreton, Beamish, and McKinley). Also, there are efforts to prohibit and limit harvesting (Johnson 60-65), though largely depressed lakes cannot recover through this method, calling for a combination of methods.
The Wisconsin waters hold a precious species of fish, one which has recently proved economically beneficial. Scrambling for a piece of this fortune undermines the self- sufficient reproduction of the fish, calling for protective measures. Since one method will not save the situation, a solution is in the combination of methods such as aquaculture, limited harvesting, and regularized selling. All of this can, however, work only if protective measures are taken from a long-term perspective. Hope you are able to visit the next Sturgeon Fest to help protect these amazing fish right here in Wisconsin.
Becker GC (1983) Fishes of Wisconsin. The University of Wisconsin Press, Madison, WI, 1052 pp
Anderson, E. R. “Lake sturgeon (Acipenser fulvescens) management and culture in Minnesota and Michigan.” Proceedings of a Workshop on the Lake Sturgeon. 1987
Johnson, James Edward, and Beth D. McAleer. Protected fishes of the United States and Canada. American Fisheries Society, 1987.
Enblon, John. A Biological Reconnaissance of the Upper Mississippi River. Minnesota: Minnesota Department of Natural Resources, Division of Fish and Wildlife, Ecological Services, 1997. Print.
LeBreton, Greg T. O, F. W. H Beamish, and R. Scott McKinley. Sturgeons and Paddlefish of North America. Dordrecht: Kluwer Academic Publishers, 2010. Print.
Miller, Michael J. “The Ecology and Functional Morphology of Feeding Of North American Sturgeon and Paddlefish.” Sturgeons and Paddlefish of North America 87-102. Web. 3 Feb. 2018.
Mims, Steven et al. Production of Sturgeon. Mississippi: Southern Regional Aquaculture Center, 2002. Web. 2 Feb. 2018.
Peterson, Douglas L., Paul Vecsei, and Cecil A. Jennings. “Ecology and Biology of the Lake Sturgeon: A Synthesis of Current Knowledge of a Threatened North American Acipenseridae.” Reviews in Fish Biology and Fisheries 17.1 (2006): 59-76. Web. 3 Feb. 2018.
Robins, C. Richard et al. A Field Guide to Atlantic Coast Fishes. Boston: Houghton Mifflin, 1999. Print.
Stelzer, Robert S. et al. “Carbon Sources for Lake Sturgeon in Lake Winnebago, Wisconsin.” Transactions of the American Fisheries Society 137.4 (2008): 1018-1028. Web. 2 Feb. 2018.
Van Eenennaam, Joel P., Frank A. Chapman, and Peter L. Jarvis. “Aquaculture.” Sturgeons and Paddlefish of North America (2004): 277-311. Web. 2 Feb. 2018.
Wisconsin. Department of Natural Resources. The Shovelnose Sturgeon, Scaphirynchus platorynchus (Rafinesque) In the Red Cedar-Chippewa River System, Wisconsin: An Interim Report. Madison: Department of Natural Resources, 1975. Print.