- Bishop, California, United States
Saline lakes worldwide are undergoing drying, and as lake levels fall and areas contract, salinities increase. There is a critical need for data on salinity impacts to guide conservation for recovery of the aquatic productivity that... more
Saline lakes worldwide are undergoing drying, and as lake levels fall and areas contract, salinities increase. There is a critical need for data on salinity impacts to guide conservation for recovery of the aquatic productivity that supports migratory and breeding birds that depend on these habitats. Brine flies are key sources of food to these birds and are adapted for life in saline waters owing to their capacity for osmotic regulation. The sublethal effects on growth, development and reproduction were determined in experiments and field observations with the alkali fly Cirrula hians from alkaline lakes of differing salinity. The cost of osmoregulation to fitness from rising salinity was exhibited in slower growth rates of larvae, smaller size at maturity of pupae, reduced adult emergence success, and lower fecundity. The results identify a salinity management range of 25 to 100 g L−1 that would optimize life history traits and productivity of this insect as a food source for birds.
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Data matrix on several spreadsheet tabs that show stream sites monitored by name and date. One tab with metals chemsitry, another that converts metals chemistry to cumulative criterion units of toxicological response, and another tab that... more
Data matrix on several spreadsheet tabs that show stream sites monitored by name and date. One tab with metals chemsitry, another that converts metals chemistry to cumulative criterion units of toxicological response, and another tab that shows the density of macroinvertebrate taxa corresponding to the site and date where water quality data was collected.<br>
An integral component of stream restoration management is the monitoring of performance indicators that measure the progress of recovery (National Research Council 1992). Given the uncertainties inherent in the physical and biological... more
An integral component of stream restoration management is the monitoring of performance indicators that measure the progress of recovery (National Research Council 1992). Given the uncertainties inherent in the physical and biological response of a stream to restoration efforts, an effective monitoring program can form the basis of
Issues for detecting sediment supply effects on stream habitat and benthos sediment transport is a natural process of streams, characterized by high temporal and spatial variability anthropogenic influence is often diffuse (non-point),... more
Issues for detecting sediment supply effects on stream habitat and benthos sediment transport is a natural process of streams, characterized by high temporal and spatial variability anthropogenic influence is often diffuse (non-point), (non point), and complex to characterize and link to stream responses stream hydrology is coupled to sediment dynamics, and land use changes are likely to influence both sediment supplies and responses may be acute and/or chronic and vary in duration, frequency, seasonality, and severity effects of sediment transport vs. deposition vary as a function of stream gradient, delivery source, and timing of flux/re-suspension other effects from landscape disturbance may be difficult to separate from sedimentation (nutrients, riparian…..) Questions and Study Objectives What is the relationship of the macroinvertebrate community and metrics to both reach-scale reach scale and local-scale local scale variation in sediment deposition? What is the natural backgro...
Bioassessment programs within California, in other states, and among federal agencies have used different methods to collect and analyze stream invertebrate samples. While this has created concern and confusion over the comparability of... more
Bioassessment programs within California, in other states, and among federal agencies have used different methods to collect and analyze stream invertebrate samples. While this has created concern and confusion over the comparability of these many disparate sources of data, few studies have attempted to evaluate differences in performance of these methods and reconcile the results produced from varied approaches. To obtain directly comparable data sets we conducted concurrent sampling at 40 sites using three bioassessment methodologies that differed at each stage, from field sample collection to laboratory processing and data analysis (California Stream Bioassessment Protocol, Region 5 US Forest Service, and UC-SNARL methods). We used a performance-based methods system to compare precision, bias, discrimination, accuracy, and correlations among multimetric and predictive model output assessment scores. Reference and test sites were first identified using local and upstream watershed...
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Submitted to Lahontan Regional Water Quality Control Board In partial completion of Lahontan Contract # 03-173-256
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Mountains are global biodiversity hotspots where cold environments and their associated ecological communities are predicted to be threatened by climate warming. Considerable research attention has been devoted to understanding the... more
Mountains are global biodiversity hotspots where cold environments and their associated ecological communities are predicted to be threatened by climate warming. Considerable research attention has been devoted to understanding the ecological effects of alpine glacier and snowfield recession. However, much less attention has been given to identifying climate refugia in mountain ecosystems where present-day environmental conditions will be maintained, at least in the near-term, as other habitats change. Around the world, montane communities of microbes, animals, and plants live on, adjacent to, and downstream of rock glaciers and related cold rocky landforms (CRL). These geomorphological features have been overlooked in the ecological literature despite being extremely common in mountain ranges worldwide with a propensity to support cold and stable habitats for aquatic and terrestrial biodiversity. CRLs are less responsive to atmospheric warming than alpine glaciers and snowfields du...
... Marcos R. Camara 145-148 Anostracan cysts found in California salt lakes William D. Shepard, Richard E. Hill 149-158 Thermal, mixing, and oxygen regimes of the Salton Sea, California, 1997-1999 James M. Watts, Brandon K. Swan, Mary... more
... Marcos R. Camara 145-148 Anostracan cysts found in California salt lakes William D. Shepard, Richard E. Hill 149-158 Thermal, mixing, and oxygen regimes of the Salton Sea, California, 1997-1999 James M. Watts, Brandon K. Swan, Mary Ann Tiffany, Stuart H. Hurlbert 159 ...