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HabRate: a literature and stream survey based habitat rating model
Jennifer L. Burke, Kim K. Jones, and Jeffrey M. Dambacher
Abstract
Fishery managers are commonly tasked with the basic question “Will the
contemporary habitat above a barrier support the fish populations that
historically resided in the watershed?” Managers in central Oregon were
confronted with that question in an effort to reestablish fish
populations in 375 kilometers of stream above the Round Butte-Pelton Dam
complex (Rkm 161) on the Deschutes River. Stream surveys had been
conducted in most of the available stream habitat, but had not been
synthesized in a form that allowed managers to view the quality and
complexity of stream habitat in an easily-understandable fashion. In
response, we developed a limiting factors model (HabRate) that assessed
the potential quality of stream habitat using stream survey data for
each juvenile life stage of salmon and steelhead. The model was
developed for a specific application to the middle Deschutes River basin
in Oregon, but was intended for general application to Pacific Northwest
basins. To paramatize the model, we summarized available literature on
salmonid habitat requirements. Habitat criteria were developed for
discrete life history stages (i.e. spawning, egg survival, emergence,
summer rearing, and winter rearing) and used to rate the quality of
stream reaches as poor, fair, or good, based on attributes relating to
stream substrate, habitat unit type, cover, gradient, temperature, and
flow. Reach level summaries of stream habitat data were entered into MS
Excel, and interpreted by a series of algorithms to provide a limiting
factor assessment of potential egg-to-fry and fry-to-parr survival for
each reach. Model output lists habitat quality by species and life stage
for each reach of stream. The model is a decision making tool that is
intended to provide a qualitative assessment of the habitat potential of
stream reaches within a basin context. Design criteria for the model
were simplicity, flexibility, and transparency. While HabRate was based
on our interpretations of the published literature, specific criteria
for habitat quality were structured to be easily adjusted where
interpretations differ from ours. Information not common to standard
stream survey designs, such as seasonal flow or temperature extremes can
be included as input from professional judgment. The results were
integrated into a GIS coverage coupled with the stream network and
habitat data to provide a comprehensive map-based perspective of habitat
quality in a watershed.
Design criteria for the model were 1) simplicity and 2) flexibility. It attempts
to work only from published literature, and rating values for high, medium, and
low can be easily changed. Information not found in standard stream surveys,
such as seasonal flow or temperature limitations can be included based on
professional judgment.
To download HabRate files:
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HabRate for
Basin Habitat Data
- HabRate
for Oregon Plan Habitat Data
- Includes MS Excel
spreadsheet with algorithms
- MS Access database with
example data and queries to create specific metrics
- Instructions on how to use
queries developed in the MS Access database
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