Water Stewardship Information Sources

ID 2032
Citation Gottesfeld, AS, Hassan, MA, Tunnicliffe, JF and Poirer, RW. 2004. Sediment dispersion in salmon spawning streams: The influence of floods and salmon redd construction. Journal of the American Water Resources Association 40(4):1071-1086.
Organization Skeena Fisheries Commission
URL http://skeenafisheries.ca/images/uploads/documents/Gottesfeld-et-al.-2004-JAWRA_.pdf
Abstract/Description or Keywords Magnetically tagged particles were used to investigate
the effects of sockeye salmon (Oncorhynchus nerka) and floods on
the dispersion of coarse bed material in the Stuart-Takla region,
British Columbia, Canada. The dominant annual sediment transporting
event in the channels is the snowmelt flood events, with
lesser activity usually accomplished during summer floods. Annually
in August, the channel bed material is reworked by the Early
Stuart sockeye salmon spawning, as the fish excavate the
streambed to deposit and bury their eggs. These nesting cavities
are called redds. Results from 67 tracer recovery experiments over
five years were highly variable, subject to the magnitude of floods
and the returning population of salmon. Overall, the depositional
pattern from nival flood events usually demonstrated a high degree
of clast mobilization, long travel distances (up to 150 m), and mean
depths of burial up to 18 cm. Summer flood events showed somewhat
lower rates of mobilization, distances of travel, and depths of
burial. Although the fish did not move the tracers very far, their
effect on the bed was generally quite pervasive – up to 100 percent
of the clasts were mobilized, and the depth of burial was considerable
(mean burial depths up to 14 cm). The amount of vertical mixing
of sediment by salmon was often on the same order of
magnitude as flood events. The significant vertical mixing of sediments
by the fish has important implications for the mobility of
sediment in the stream. Since any armoring layer formed during
high flows throughout the year is subject to the bioturbation of
salmon, this suggests that the transport threshold in the creeks
remains relatively low. Salmon likely play an integral role in the
sediment transport dynamics and annual sediment budget of the
lower reaches of these creeks.
(KEY TERMS: erosion; sedimentation; sockeye salmon; bed load
transport; tracer studies; forest hydrology; watershed management;
bioturbation.)
Information Type Article
Regional Watershed Stuart-Takla, Fraser
Sub-watershed if known
Aquifer #
Comments
Project status
Contact Name Allan Gottesfeld
Contact Email [email protected]