This document contains the RBP Visual-Based Habitat Assessment method. It also describes the protocols and metrics used to assess the condition of (1) phytoplankton, (2) benthic macroinvertebrate and (3) fish assemblages (e.g., Index of Biotic Integrity). These RBPs address different levels of rigor, ranging from screening methods to more intensive bioassessments.
Purpose
RBP provides an integrated assessment, comparing habitat (e.g., physical structure, flow regime), water quality and biological measures with empirically defined reference conditions (via actual reference sites, historical data, and/or modeling or extrapolation).
Applicable Habitat Type: Nontidal Open Water : Wadeable rivers & streams
Method Description
First, perform the Visual-based habitat assessment as follows.
(1) Select the reach to be assessed.
(2) Complete the Physical Characterization and Water Quality Field Data Sheet which contains information about weather conditions, stream characteristics (e.g., stream subsystem, type, and origin), watershed features (e.g., surrounding land use, watershed nonpoint source pollution, watershed erosion), riparian vegetation, instream features (e.g., reach length, stream width, reach area, stream depth), large woody debris, aquatic vegetation, water quality (e.g., temperature, water odors), and sediment/substrate (e.g., sediment oils, sediment deposits).
(3) Complete the Visual-Based Habitat Assessment Data Sheet, which lists 10 habitat parameters to be evaluated. A brief set of decision criteria is given on the data sheet for each parameter corresponding to each of 4 categories reflecting a continuum of conditions (optimal, suboptimal, marginal, and poor) and associated scores (scale is 0-20 or 0-10, depending upon the habitat parameter). The user selects the condition and score that best describes the stream reach, and scores are summed (scale 0-200).
Secondly, sample one or more assemblages (periphyton, benthic macroinvertebrates, and/or fish) using selected sampling protocols and metrics (e.g., Index of Biotic Integrity). Analyze and integrate the data to provide assessment of biological condition.
Comment from author: I suggest doing the bioassessment first, so that the instream parameters are better assessed having sampled the reach. Don't forget that the physical habitat is more than just the reach. Also, do as a team, not individual (this decreases subjectivity).
A major step is the calibration of the index for the particular stream class. This is necessary before analysis can be done.
Sample data sheets are available at: http://www.epa.gov/owow/monitoring/rbp
The RBPs have been summarized into a tutorial for use in EPA's Watershed Academy. Go to the EPA/OWOW website for instruction in their use. Also, the RBPs have been endorsed by the European Union and are being used in a multi-country research project to determine reference conditions for their ecological classes. This is part of the EU Water Framework Directive agreement.
Expertise, Training
RBP should be used by a biologist trained in the methods for the applicable region or state in order to make survey results as broadly applicable and consistent as possible.