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Monitoring of wild fish health at selected sites in the Great Lakes Basin: methods and preliminary results

February 28, 2014

During fall 2010 and spring 2011, a total of 119 brown bullhead (Ameiurus nebulosus), 136 white sucker (Catostomus commersoni), 73 smallmouth bass (Micropterus dolomieu), and 59 largemouth bass (M. salmoides) were collected from seven Great Lakes Basin Areas of Concern and one Reference Site. Comprehensive fish health assessments were conducted in order to document potential adverse affects from exposure to complex chemical mixtures. Fish were necropsied on site, blood samples obtained, pieces of liver, spleen, kidney, gill and any abnormalities placed in fixative for histopathology. Liver samples were saved for gene expression analysis and otoliths were removed for aging. A suite of fish health indicators was developed and implemented for site comparisons and to document seasonal effects and species differences in response to environmental conditions. Organism level (grossly visible lesions, condition factor), tissue level (microscopic pathology, organosomatic indices, micronuclei, and other nuclear abnormalities), plasma factors (reproductive steroid hormones, vitellogenin), and molecular (gene expression) indicators were included. This report describes the methods and preliminary results.

Citation Information

Publication Year 2014
Title Monitoring of wild fish health at selected sites in the Great Lakes Basin: methods and preliminary results
DOI 10.3133/ofr20141027
Authors Vicki Blazer, Patricia M. Mazik, Luke R. Iwanowicz, Ryan Braham, Cassidy Hahn, Heather L. Walsh, Adam Sperry
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Open-File Report
Series Number 2014-1027
Index ID ofr20141027
Record Source USGS Publications Warehouse
USGS Organization New Jersey Water Science Center