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Goldstein, R.M., 1995, Aquatic Communities and Contaminants in Fish
from Streams of the Red River of the North Basin, Minnesota and North
Dakota: U.S. Geological Survey Water-Resources Investigations Report
95-4047, 34p.
Abstract
Available data on the ecology of aquatic organisms in the Red River of the
North Basin, a study unit of the U. S. Geological Survey's National Water
Quality Assessment, were collated from numerous sources. Lack of information
on invertebrates and algae precluded a general summary of distribution and
ecology. Data on fish species distributions in the major streams of the Red
River of the North Basin were analyzed based on the drainage basin area of the
stream and the number of ecoregions the stream flowed through. Species
richness increased with both basin area (log basin area in square kilometers,
R2=0.41, p=0.0055) and the number of ecoregions a river flowed
through. However, theses two factors are autocorrelated. The larger the basin,
the more likely that the river will flow through more than one ecoregion. A
cluster analysis identified five river groups based on similarity of species
within the fish community. Analysis of trophic and taxonomic composition
provided justification for the cluster groups. There were significant
differences (p=0.05) in the trophic composition of the river cluster groups
with respect to the number of predator species, benthic insectivore species,
and general insectivore species. Although there were no significant
differences in the number of species in the bass and sunfish family or the
sucker family, the number of species in the minnow family and darter subfamily
were different (p=0.05) among the groups identified by cluster analysis. Data
on contaminant concentrations in fish from the Red River of the North
indicated that most trace elements and organochlorine compounds present in
tissues were not at levels toxic to fish or humans. Minnesota and North
Dakota, however, have issued a fish consumption advisory based on levels of
mercury and PCBs bound in some species.
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U.S. Geological Survey