Little Rock Creek Biological Survey, Habitat Evaluation, and GIS Analysis

Abstract

Little Rock Creek was listed as a Minnesota 303(d) impaired water in 2004, resulting in a TMDL (total maximum daily load) study for aquatic life due to the lack of a cold water fish assemblage. Data presented in this report provide biological survey summary information on the stream community associated with Little Rock Creek (LRC), local habitat measurements, and land use/land cover characteristics of the watershed in an effort to identify causes of impairment. This report will describe the biotic stream community and quantify potential relationships among landuse characteristics, local habitat conditions, and biotic assemblages including fish, and macroinvertebrates. This report will focus on trends in the macroinvertebrate and fish communities (abundance and functional traits), physicochemical, and local habitat conditions from five sample locations within the Little Rock Creek watershed (Fig. 1a,b). Additional data is provided by the Minnesota Pollution Control Agency (MPCA), and an earlier Natural Resources Research Institute (NRRI) study, for the purpose of regional comparisons (hereafter referred to as ‘MPCA and/or NRRI regional comparison sites;’ Figs. 2,3). Data collected by the MPCA between 1996-2006 includes 16 streams in the same area as the TMDL sites. A 1998 sampling efforts at 18 streams (c.f., Hutchens et al. 2009) in southeastern Minnesota were conducted in a heavily agricultural area to determine landuse/landscape interactions with macroinvertebrate and fish communities.