Geology topics

Nolan P. Banish

Publications and source records attributed to Nolan P. Banish.

4 recordsLinked to original sources

USGS2023

Co-production of models to evaluate conservation alternatives for a threatened fish in a rapidly changing landscape

Reintroductions are one means of managing species distributions, but the feasibility of such efforts is uncertain. Here we consider reintroduction for threatened bull trout ( Salvelinus confluentus ) that currently occupy a small fraction of historically occupied habitats in the upper Klamath River basin owing to climate warming and human modifications of ecosystems. We engaged stakeholders across multiple organizations to co-produce a decision support model that estimated the potential of reintroduction to establish new populations and persistence of donor populations. Stakeholders identified recipient and donor populations, strategy (e.g., artificial propagation, translocation), number of individuals, and life stage of bull trout. The most optimal decision for reintroduction was artificial propagation of 10,000 fry into Annie Creek. This strategy may have negative consequences on donor populations, with the exception of Sun Creek, which was resilient to simulated removal of bull trout. Donor populations and recipient streams identified as most feasible were generally consistent across all of these scenarios. During model development, however, an unexpected and intense wildfire affected half of the streams considered and may have dramatically impacted donor populations. With models in hand from the initial feasibility assessment, we adapted them to further evaluate the potential of supplementation following this massive disturbance. Overall, results of this study indicate the value of developing co-produced tools that can be rapidly adapted to evaluate the consequences of whole-system transformations in near-real-time assessments.

Oregon↗

USGS2016

Thermal regimes, nonnative trout, and their influences on native Bull Trout in the Upper Klamath River Basin, Oregon

The occurrence of fish species may be strongly influenced by a stream’s thermal regime (magnitude, frequency, variation, and timing). For instance, magnitude and frequency provide information about sublethal temperatures, variability in temperature can affect behavioral thermoregulation and bioenergetics, and timing of thermal events may cue life history events, such as spawning and migration. We explored the relationship between thermal regimes and the occurrences of native Bull Trout Salvelinus confluentus and nonnative Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta across 87 sites in the upper Klamath River basin, Oregon. Our objectives were to associate descriptors of the thermal regime with trout occurrence, predict the probability of Bull Trout occurrence, and estimate upper thermal tolerances of the trout species. We found that each species was associated with a different suite of thermal regime descriptors. Bull Trout were present at sites that were cooler, had fewer high-temperature events, had less variability, and took longer to warm. Brook Trout were also observed at cooler sites with fewer high-temperature events, but the sites were more variable and Brook Trout occurrence was not associated with a timing descriptor. In contrast, Brown Trout were present at sites that were warmer and reached higher temperatures faster, but they were not associated with frequency or variability descriptors. Among the descriptors considered, magnitude (specifically June degree-days) was the most important in predicting the probability of Bull Trout occurrence, and model predictions were strengthened by including Brook Trout occurrence. Last, all three trout species exhibited contrasting patterns of tolerating longer exposures to lower temperatures. Tolerance limits for Bull Trout were lower than those for Brook Trout and Brown Trout, with contrasts especially evident for thermal maxima. Our results confirm the value of exploring a suite of thermal regime descriptors for understanding the distribution and occurrence of fishes. Moreover, these descriptors and their relationships to fish should be considered with future changes in land use, water use, or climate.

Oregon↗

USGS2016

Efficiency of portable antennas for detecting passive integrated transponder tags in stream-dwelling salmonids

Portable antennas have become an increasingly common technique for tracking fish marked with passive integrated transponder (PIT) tags. We used logistic regression to evaluate how species, fish length, and physical habitat characteristics influence portable antenna detection efficiency in stream-dwelling brown trout ( Salmo trutta ), bull trout ( Salvelinus confluentus ), and redband trout ( Oncorhynchus mykiss newberrii ) marked with 12-mm PIT tags. We redetected 56% (20/36) of brown trout, 34% (68/202) of bull trout, and 33% (20/61) of redband trout after a recovery period of 21 to 46 hours. Models indicate support for length and species and minor support for percent boulder, large woody debris, and percent cobble as parameters important for describing variation in detection efficiency, although 95% confidence intervals for estimates were large. The odds of detecting brown trout (1.5 ± 2.2 [mean ± SE]) are approximately four times as high as bull trout (0.4 ± 1.6) or redband trout (0.3 ± 1.8) and species-specific differences may be related to length. Our reported detection efficiency for brown trout falls within the range of other studies, but is the first reported for bull trout and redband trout. Portable antennas may be a relatively unbiased way of redetecting varying sizes of all three salmonid species.

Oregon↗

USGS2011

Distribution and habitat associations of radio-tagged adult Lost River suckers and shortnose suckers in Upper Klamath Lake, Oregon

Radiotelemetry was used to investigate the summer distribution and diel habitat associations of endangered adult Lost River suckers Deltistes luxatus and shortnose suckers Chasmistes brevirostris in northern Upper Klamath Lake, Oregon. From 2002 to 2004, Lost River and shortnose suckers were tracked by boat, and water depth and water quality were measured at each fish location. A series of water quality monitors were deployed in northern Upper Klamath Lake to provide temporal information on ambient temperature, pH, and dissolved oxygen, and water samples were collected to assess chlorophyll a concentration. Suckers moved into northern Upper Klamath Lake during June and began to leave in late September each year. Kernel density estimates revealed differences in the distribution in the northern portion of Upper Klamath Lake in 2002 and 2004. In 2003, however, both Lost River and shortnose suckers were commonly located within and offshore from Pelican Bay, a shallow (1.0-2.0 m), groundwater-influenced area of Upper Klamath Lake. This was especially obvious beginning in late July of 2003, concurrent with reduced dissolved oxygen levels (<4.0 mg/L) in the northern portion of Upper Klamath Lake that resulted from a die-off of the cyanobacterium Aphanizomenon flos-aquae . Both Lost River and shortnose suckers were generally associated with water depths greater than the mean depth (2.8 m) of northern Upper Klamath Lake. Evidence ratios did not suggest diel differences in depth, temperature, dissolved oxygen, or pH at sucker locations. Both Lost River and shortnose suckers generally occupied depths greater than 2.0 m, except when suckers sought refuge in Pelican Bay during periods of poor water quality. Despite the potential for increased avian predation, suckers appeared to benefit from moving into Pelican Bay rather than staying in areas where dissolved oxygen was low. Pelican Bay appears to be an important refugium and thus may be important for sucker conservation.

Oregon↗