What do you get when you cross a catfish and an eel? The result is an Ohio-native fish called the burbot. Burbots (Lota lota) are the only member of the cod family (Lotidae) that live completely in freshwater (Stapanian et al., 2008). In Ohio, burbots are found primarily in Lake Erie (Rice, D. & Zimmerman, B., 2019). Populations of this species are difficult to study due to their choice in habitat. Burbot need cooler water temperatures in order to survive and reproduce. They spend the warmer months in the deeper, eastern basin of Lake Erie where the water is cooler. In the cooler months, burbot move into shallower waters in the central and western basins of the lake (Trautman, 1997).
Although global burbot populations are doing well, many regional populations are threatened or extirpated. Burbots have been extirpated from Europe and the United Kingdom and are threatened or endangered in most of North America. In Ohio, they are listed as a species of concern. (Ohio Department of Natural Resources, 2012). Because burbot are not a popular commercial fish species, few have considered the species when deciding upon management plans.
One factor that has a large, negative impact on Lake Michigan, Huron and Ontario burbot populations is the sea lamprey. Before sea lamprey populations were controlled and their numbers reduced as a result, they mercilessly preyed upon burbots, causing burbot populations to decline dramatically. In Lake Erie, the main factor influencing the decline in burbot population has been due to a combination of decreased water quality—a result of pollution—habitat degradation, and past overexploitation (Stapanian et al., 2010).
Why is it important that we conserve this species? While they may not be the best game or commercial fishing species, burbot are a fantastic indicator species. An indicator species is an organism that serves as a measure of the environmental conditions that exist in a given locale; meaning, the organism helps highlight certain characteristics within its environment (Encyclopædia Britannica, 2016). Because they are very sensitive to disturbance (changes in their environment), burbot populations can be monitored to help gain insight as to how human actions are impacting burbots’ environment (Stapanian et al., 2010). Burbot population numbers in their cold month habitats can also serve as an indicator of the impacts of climate change. Less burbot will be found in shallow waters as the water temperature rises. Along with burbot, these rising water temperatures can have negative, long-lasting impacts on other biota in Lake Erie.
Link to NOAA CoastWatch Great Lakes Water Temperature Statistics: https://coastwatch.glerl.noaa.gov/statistic/
In order to help conserve our burbots here in Ohio, there are some easy things we can do to help. We can improve our water quality by reducing the amount of pollution entering our waterways—this can be done by recycling, creating less one-use-plastic waste, becoming educated on the impacts of industrial runoff, etc. We can also help combat habitat degradation by supporting local, regional, state, and national organizations and agencies that are fighting to conserve lands and restore those that were damaged.
Fascinating, borderline bizarre, and scientifically invaluable, the burbot is an Ohio species that deserves our attention. By studying their behaviors, humans are aided by burbots in determining habitat quality in Lake Erie. In this way, we can help conserve their populations and the populations of many aquatic species for generations to come.
Encyclopædia Britannica. 2016. Indicator species. Encyclopædia Britannica, inc. https://www.britannica.com/science/indicator-species. Accessed: 9/23/19
Ohio Department of Natural Resources. 2012. Division of Wildlife. Burbot. http://wildlife.ohiodnr.gov/species-and-habitats/species-guide-index/fish/burbot. Accessed 9/24/19.
Rice, D. & Zimmerman, B. 2019. A Naturalist’s Guide to the Fishes of Ohio. Ohio Biological Survey, Columbus.
Stapanian, M., Bronte, C., Ebener, M., Lantry, B.F. & Stockwell, J.D.. (2008). Status of Burbot populations in the Laurentian Great Lakes. American Fisheries Society. 59:111-130. https://www.fws.gov/midwest/Fisheries/scientific-pubs/p-2007-4.pdf. Accessed 9/24/19.
Stapanian, M. A., Paragamian, V. L., Madenjian, C. P., Jackson, J. R., Lappalainen, J. , Evenson, M. J. & Neufeld, M. D. (2010), Worldwide status of burbot and conservation measures. Fish and Fisheries, 11: 34-56. doi: 10.1111/j.1467-2979.2009.00340.x. Accessed 9/23/19.
Trautman, M. B. 1957. The fishes of Ohio. Ohio State University Press, Columbus.