Maintaining the health of the rich biodiversity of fishes and other aquatic organisms in North America is essential for conservation, environmental compliance, and responsible resource management.
Our biologists can provide professional biotic assessments, fish population monitoring, and aquatic resource management services. If your business—whether in utilities, extraction, development, or conservation — needs regular environmental impact assessments but lacks in-house fisheries biologists, we provide cost-effective, expert solutions.
Why Choose Us?
Environmental Compliance: Our assessments meet state and federal environmental regulations, helping you fulfill legal obligations.
Expert Biologists: Our team is trained in and follows American Fisheries Society and state-approved sampling methods.
Accurate Ecosystem Analysis: We use metrics developed and approved by state and federal regulatory agencies, including the Index of Biotic Integrity (IBI), to assess fish populations and overall ecosystem health. These indices are specifically tailored to the fishes found in each state and/or subregion of the state, ensuring the highest accuracy.
Comprehensive Reports: We provide detailed documentation and voucher specimens, ensuring smooth regulatory submissions.
Need biomonitoring services without the hassle of hiring a full-time team? Let’s work together to protect aquatic ecosystems while keeping your operations compliant and efficient.
Contact us today to schedule a professional biotic assessment!
The southeastern U.S. harbors a diversity of aquatic habitats and species unparalleled in North America. Over 1,800 species of fishes, mussels, snails, turtles and crayfish can be found in the more than 70 major river basins of the region. More than 500 of these species are endemic to the southeastern states or to individual watersheds within them. The southeastern U.S. has been agricultural for centuries, and also has some of the fastest growing metropolitan areas in the country (Sudduth et al. 2007). About 30% of stream miles in this region are on the U.S. Environmental Protection Agency’s 303d list of impaired waterbodies.
The role of habitat alteration in the imperilment of freshwater fishes is well established (Rahel 2000). Fish assemblage homogenization has occurred worldwide, usually as a result of anthropogenic impacts. Non-native fish introductions, dam construction, and flow alteration are three of the most common factors influencing the structure of fish and invertebrate assemblages residing in riverine environments (Rahel 2000). The usual result of such impacts is a reduction or loss of specialized, native species associated with an increase of non-native, generalist species (Walters et al. 2003). Some sources of habitat stress are direct, such as stream piping, relocation, shoreline armoring, excessive siltation, and contaminants, and often associated with development, commerce, agriculture, forestry and mining. Less direct stressors, especially human population growth and climate change, cumulatively exert a persistent and growing landscape-level effect on fish and their habitats.
Information on the spatial distribution of fish species and species richness at sampling sites is important to the conservation and management of fishes. Biologists have developed metrics that can assess the biotic health of ecosystems based on frequency, occurrence, and diversity of aquatic organisms, including fishes. The most common of these is the Index of Biotic Integrity (IBI), which incorporates information on the occurrence and abundance of tolerant and sensitive fish species into a numerical score that infers biotic health of the system sampled. Biotic integrity has been defined by Karr and Dudley (1981) as the ability to support and maintain a balanced, integrated, adaptive community of organisms comparable to that of the natural habitat of the region. Since the passage of the Water Pollution Control Act of 1972, water regulatory agencies have been charged with restoring and maintaining the biological, or biotic, integrity of the nation’s water resources (Karr 1991).
The IBI was developed to assess the health of aquatic communities based on the functional and compositional attributes of fish populations (Karr 1991). It has become widely-used for assessing the status of stream fish communities and the overall ecological status of streams. Originally developed for midwestern streams, the IBI has been modified numerous times to enable its use in other regions of the U.S. (reviewed by Miller et al. 1988). The IBI integrates characteristics of the fish community, population, and individual organism to assess biological integrity at a sample site (Karr 1987). It is a broadly based ecological index that assesses community structure and function at several trophic levels and gauges biotic integrity against an expectation, based on minimal disturbance in that region. Unlike other metrics, the IBI incorporates professional judgment into the selection of metrics and the development of scoring criteria. Furthermore, the IBI has been shown to be a statistically valid approach for evaluating water resources and establishing regulatory policies (Fore et al. 1994).
All IBI sampling for fishes is based on electrofishing sites of fixed length, usually one site per stream. Sampling is conducted using anywhere from 1-3 backpack electrofishing units and/or an electrofishing tow barge. Choice of gear is determined by stream size (i.e., width). All fish are identified, counted, and bulk weighed by species. Prior to sampling each site is surveyed to identify habitat and geomorphology characters that also help support the IBI findings. Scoring the IBI is based on known metrics of biotic health, such as the number of native species encountered, the number of tolerant or sensitive species encountered, proportion of sunfish in the sample, number of abnormalities found on fishes in the samples, etc. Each metric is scored as a 1 (poor), 3 (average), or 5 (good) and summed together to obtain the IBI score. The most accurate IBIs are derived from metrics that are specifically tailored to the fishes found in each state and/or subregion of the state. Aquatic Environmental Services uses the most current IBI scoring metrics available for each state to ensure the most accurate assessment of biotic integrity is attained. Deliverables include voucher specimens required by state regulatory agencies and a comprehensive report of findings and IBI scores that can be submitted to the regulatory agency by the client to fulfill needed obligations.
References
Fore, L.S., J.R. Karr, and L.L. Conquest. 1994. Statistical properties of an index of biological integrity used to evaluate water resources. Canadian Journal of Fisheries and Aquatic Sciences 51: 1077-1087.
Karr, J.R. 1987. Biological monitoring and environmental assessment: a conceptual framework. Environmental Management 112: 249-256.
Karr, J.R. 1991. Biological integrity: a long-neglected aspect of water resource management. Ecological Applications 1(1): 66-84.
Karr, J.R. and D.R. Dudley. 1981. Ecological perspective on water quality goals. Environmental Management 5(1): 55-68.
Miller, D. L., P. M. Leonard, R. M. Hughes, J. R. Karr, P. B. Moyle, L. H. Schrader, B. A. Thompson, R. A. Daniel, K. D. Fausch, G. A. Fitzhugh, J. R. Gammon, D. B. Halliwell, P. L. Angermeier, and D. J. Orth. 1988. Regional applications of an Index of Biotic Integrity for use in water resource management. Fisheries 13(5): 12-20.
Rahel, F. J. 2000. Homogenization of fish faunas across the United States. Science 288(5467): 854-856.
Sudduth, E. B., J. L. Meyer, and E. S. Bernhardt. 2007. Stream restoration practices in the southeastern United States. Restoration Ecology 15: 573-583.
Walters, D. M., D. S. Leigh, and A. B. Bearden. 2003. Urbanization, sedimentation, and the homogenization of fish assemblages in the Etowah River Basin, USA. Hydrobiologia 494: 5-10.
