TITLE:
Benthic Macroinvertebrates of Bull Run Creek: A Pre-Restoration Baseline
AUTHORS:
Joe Corsini, John Zakrajsek, Robert Hassmiller
KEYWORDS:
Benthic Macroinvertebrates, Restoration, Diversity, Anadromous Fish, Beaver
JOURNAL NAME:
Natural Resources,
Vol.14 No.6,
June
30,
2023
ABSTRACT: In North America, disturbed riparian zones have had
a deleterious effect on the life cycles of anadromous fish, especially the
commercially and culturally important salmon and steelhead. The result has been
a significant reduction in the numbers and average size of these fish. Tributaries
of the John Day River are important spawning waters for western populations of
these fish, and the National Forest Service and the Confederated Tribes of the
Umatilla Indian Reservation are cooperating to restore floodplains and riparian
zones in a number of these headwater tributaries. Herein we have conducted a
pre-restoration study of macroinvertebrates and basic water quality parameters
in one of these important spawning locations in central Oregon, Bull Run Creek.
Results of the turbidity, pH, dissolved Oxygen, and temperature determinations
indicate that overall water quality is good, and benthic macroinvertebrate
sampling yielded a number of sensitive organisms, including members of
Chloroperlidae, Peltoperlidae, Ryachophilidae, Odontoceridae, and
Brachycentridae. At all sites, chironomid larvae (non-biting midge) dominated
the assemblages. The EPT Index suggests that Bull Run Creek ranges from fair to
excellent in terms of its ability to support sensitive species. Sorensen’s
Similarity Coefficient indicates varying degrees of shared diversity between
the sites, and Shannon’s entropy calculations suggest moderate to low species
diversity at all sites, including the reference site on nearby Boundary Creek.
Overall, this study indicates that Bull Run Creek is in fair condition and that
it should benefit significantly from the restoration efforts.