Freshwater
Drum
Aplodinotus grunniens Rafinesque, 1819
member of the Drum Family (Sciaenidae)
Minnesota River, Lac qui Parle County Minnesota 29 June 1985
young of the year
photos by Konrad Schmidt
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What's
In a Name? Aplodinotus
(ah-ploe-din-oh´-tuss) means "simple back" in Greek, referring to the
fin on the back not being in two parts as in perch |
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Where
Do They Live? Freshwater drum are native to the lower Mississippi, St. Croix, Minnesota, and Red river drainages of Minnesota. They apparently have been introduced recently to the St. Louis River estuary and some lakes in southwestern Minnesota. There is also a recent record from Lake of the Woods. Freshwater drum inhabit large rivers and shallow lakes with bottoms made of mostly mud or a mixture of mud and sand. They prefer slow-moving turbid (cloudy) water, but can be found in moderate currents. They are rarely found in areas of vegetation. |
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How
Big Do They Get? Freshwater drum is another species that lives longer that it scales indicate. We have to look at otoliths (ear bones) to get an accurate age for fish older than 10 years. We know that drum used to live for many years (over 45 in at least one case), but today's populations have few individuals over 7 or 8 years old in them. "Cool Fact": Native Americans used the otoliths (ear bones) from this fish as jewelry. |
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What
Do They Eat? Larval drum, like many other species in Minnesota, eat mostly copepods and waterfleas. As they grow to about 25-30 mm (about 1 in), they add small insect larvae to their diet, especially midge larvae. As fully formed juveniles and adults, freshwater drum are benthic (bottom dwellers). So they feed on bottom dwelling creatures. These include insect larvae, like midges and burrowing mayflies, crayfish, snails, and small fishes. Drum have plates of teeth in their throats for crushing food items. Many biologists have assumed that they were used to crush freshwater mussels, but we have not yet proved this. However, they do eat the exotic zebra mussel, at least in Lake Erie. |
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What
Eats Them? |
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How
Do They Reproduce? |
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Conservation
and Management |
Permission is granted for the non-commercial educational or scientific use of the text and images on this Web document. Please credit the author or authors listed below.
Photographs by Konrad P. Schmidt
Text by Nicole Paulson & Jay T. Hatch in
cooperation with
the Minnesota Department of Natural Resources' MinnAqua Aquatic Program
This page developed with funds from the
MinnAqua Program (Minnesota Department of Natural Resources, Division
of Fisheries)
and the
Sport Fish Restoration
Program (Fish and Wildlife Service, US Department of the Interior)
Maintained by Jay T. Hatch
General College and James
Ford Bell Museum of Natural History
University of Minnesota, Minneapolis/St.
Paul
Last updated 23 October 2002