PROJECT CHIEF: Tamara M. Wood
COOPERATOR: Bureau of Reclamation
Severe water quality problems in Upper Klamath Lake, Oregon, have led to critical fishery concerns for the region, including the listing of Lost River and shortnose suckers as endangered in 1988. In April 2001, the U.S. Fish and Wildlife Service (USFWS) released a Biological Opinion in which several reasonable and prudent alternatives to allow for the continued operation of the Klamath Project were presented. One of these alternatives was for the Bureau of Reclamation to develop a study plan to better determine the role of "water quality refuge" areas for adult sucker survival in Upper Klamath Lake. This study is designed to determine the behavioral response of suckers to the distribution of poor and better water quality in the northern part of the lake.OBJECTIVES
Determine the distribution and general movement patterns of radio-tagged adult Lost River and shortnose suckers in Upper Klamath Lake from June-September.
Conduct boat-tracking surveys in Upper Klamath Lake to determine specific fish locations.
Determine specific movement rates of radio-tagged adult Lost River and shortnose suckers in Upper Klamath Lake from June-September.
Establish fixed monitoring telemetry stations within Shoalwater and Ball bays to monitor for the general presence or absence of radio-tagged adult suckers.
Determine the vertical distribution of adult suckers in Upper Klamath Lake using archive tags that measure and record hydrostatic pressure at hourly intervals.
Establish an array of fixed monitoring stations that will provide the basis for a GIS model of the 1-m off-bottom water quality in the northern part of the lake.
Establish the horizontal spatial scale of variation in the lake by completing rapid, high resolution transects of water quality.
Establish the frequency, duration, spatial extent, and strength of vertical stratification with continuous datasets collected from a profiling buoy.
Collect water quality profiles associated with individual locations of radio-tagged suckers.
Determine the feasibility of using a chlorophyll-a sensor based on in situ fluorescence to map the vertical and horizontal distribution of Aphanizomenon flos-aquae in the lake.
Monitor ammonia and orthophosphate concentration in a continuous mode at one of the fixed monitoring sites using a submersible wet chemistry robot.
About 100 adult suckers will be tagged during the first year of study (targeting equal numbers of Lost River and shortnose suckers of each sex) with digitally encoded programmable transmitters that will be turned on from approximately February to October. Because of the extended life of these transmitters, the study be continued for 3 years, with the possibility that additional tagging will be conducted between years to supplement sample sizes from individuals that may die or leave the study area.
The proposed sample size of tagged fish allows for the possibility to randomly select individuals to locate and collect data on a weekly and perhaps daily basis, allowing for stronger statistical comparisons. Fish to be located will be randomly selected to allow greater inference of these results to the overall population. Also, the sampling design allows for the ability to test for individual differences before grouping observations from the tagged population.
Boat-tracking surveys will be conducted both during daylight hours and during hours of darkness to determine if differences in behavioral patterns exist between day and night (e.g., depth distribution or distance to shore). Boat tracking surveys will be supplemented by aerial surveys to determine the locations of general congregations of fish.
A network of water quality monitoring stations (8-12 sites) will be established in the northern portion of Upper Klamath Lake that will provide previously unattainable detail on the spatial and temporal variability of water quality refugia in the lake. In addition to the fixed stations, rapid, high-resolution water quality profiles along fixed transects based around monitoring stations and near shore areas will be used to establish the horizontal scale of variability in water quality. The data from the fixed stations will form the basis of a geographic information system (GIS) spatial and temporal model of the water quality conditions in the northern portion of Upper Klamath Lake. The data from the transects will provide a calibration dataset for the GIS model. Water quality data collected in conjunction with fish position will provide a validation dataset for the GIS model. Once the GIS-based water quality model is constructed, water quality data on a weekly and possibly daily level can be overlayed with fish position estimates. This approach allows for spatial and temporal analyses of fish position and water quality and will prove to be particularly useful for identifying associations of radio-tagged fish with certain areas or water quality conditions.
In addition to implanting radio transmitters in fish, a subsample of fish will be tagged with archive tags capable of recording hydrostatic pressure and water temperature. Individual fish implanted with these tags will be recaptured after the summer and the tags will be removed. The information collected will provide a detailed history of the water depth exposure of the fish.DATA
Water Quality Data, 2002
Weekly contacts of Lost River and shortnose suckers, 2002
Water Quality Data, 2003
Weekly contacts of Lost River and shortnose suckers, 2003
USGS Upper Klamath Basin Studies Page
Oregon Water Science Center Hydrologic Studies Page
Oregon Water Science Center Home Page