Skip to main content
U.S. flag

An official website of the United States government

Experimental whole-lake dissolved organic carbon increase alters fish diet and density but not growth or productivity

March 21, 2018

Negative relationships between dissolved organic carbon (DOC) concentration and fish productivity have been reported from correlative studies across lakes, but to date there have not been experimental tests of these relationships. We increased the DOC concentration in a lake by 3.4 mg L-1, using a before-after control-impact (BACI) design, to quantify the effects on the productivity and population structure of Largemouth Bass (Micropterus salmoides). Greater DOC reduced the volume of the epilimnion, the preferred habitat of Largemouth Bass, resulting in increased bass density. The likelihood that adult bass had empty diets decreased despite this increase in bass density; diet composition also changed. There was no apparent change in bass growth or condition. Overall, there was no net change in Largemouth Bass productivity. However, changes in YOY and juvenile recruitment and feeding success suggest the possibility that future effects could occur. Our results are the first to examine the effects of an increase in DOC on fish productivity through a five-year temporal lens, which demonstrates that the relationship between DOC and fish productivity is multi-dimensional and complex.

Citation Information

Publication Year 2018
Title Experimental whole-lake dissolved organic carbon increase alters fish diet and density but not growth or productivity
DOI 10.1139/cjfas-2017-0283
Authors Shuntaro Koizumi, Nicola Craig, Jacob A. Zwart, Patrick T. Kelly, Jacob P. Ziegler, Brian C. Weidel, Stuart E. Jones, Christopher T. Solomon
Publication Type Article
Publication Subtype Journal Article
Series Title Canadian Journal of Fisheries and Aquatic Sciences
Index ID 70196110
Record Source USGS Publications Warehouse
USGS Organization Great Lakes Science Center

Related Content