Modeling Global Warming Scenarios in Greenback Cutthroat Trout (\u3cem\u3eOncorhynchus Clarki Stomias\u3c/em\u3e) Streams: Implications for Species Recovery

Changes in global climate may exacerbate other anthropogenic stressors, accelerating the decline in distribution and abundance of rare species throughout the world. We examined the potential effects of a warming climate on the greenback cutthroat trout (Oncorhynchus clarki stomias), a resident salmonid that inhabits headwater streams of the central Rocky Mountains. Greenbacks are outcompeted at lower elevations by nonnative species of trout and currently are restricted to upper-elevation habitats where barriers to upstream migration by nonnatives are or have been established. We used likelihood-based techniques and information theoretics to select models predicting stream temperature changes for 10 streams where greenback cutthroat trout have been translocated. These models showed high variability among responses by different streams, indicating the usefulness of a stream-specific approach. We used these models to project changes in stream temperatures based on 2°C and 4°C warming of average air temperatures. In these warming scenarios, spawning is predicted to begin from 2 to 3.3 weeks earlier than would be expected under baseline conditions. Of the 10 streams used in this assessment, 5 currently have less than a 50% chance of translocation success. Warming increased the probability of translocation success in these 5 streams by 11.2% and 21.8% in the 2 scenarios, respectively. Assuming barriers to upstream migration by nonnative competitors maintain their integrity, we conclude that an overall habitat improvement results because greenbacks have been restricted through competition with nonnatives to suboptimal habitats, which are generally too cold to be highly productive

Ecological integrity and western water management: a Colorado perspective

Sept. 1995.Includes bibliographical references

Groundwater declines are linked to changes in Great Plains stream fish assemblages

Groundwater pumping for agriculture is a major driver causing declines of global freshwater ecosystems, yet the ecological consequences for stream fish assemblages are rarely quantified. We combined retrospective (1950–2010) and prospective (2011–2060) modeling approaches within a multiscale framework to predict change in Great Plains stream fish assemblages associated with groundwater pumping from the United States High Plains Aquifer. We modeled the relationship between the length of stream receiving water from the High Plains Aquifer and the occurrence of fishes characteristic of small and large streams in the western Great Plains at a regional scale and for six subwatersheds nested within the region. Water development at the regional scale was associated with construction of 154 barriers that fragment stream habitats, increased depth to groundwater and loss of 558 km of stream, and transformation of fish assemblage structure from dominance by large-stream to small-stream fishes. Scaling down to subwatersheds revealed consistent transformations in fish assemblage structure among western subwatersheds with increasing depths to groundwater. Although transformations occurred in the absence of barriers, barriers along mainstem rivers isolate depauperate western fish assemblages from relatively intact eastern fish assemblages. Projections to 2060 indicate loss of an additional 286 km of stream across the region, as well as continued replacement of largestream fishes by small-stream fishes where groundwater pumping has increased depth to groundwater. Our work illustrates the shrinking of streams and homogenization of Great Plains stream fish assemblages related to groundwater pumping, and we predict similar transformations worldwide where local and regional aquifer depletions occur

Colonization and extinction in dynamic habitats: an occupancy approach for a Great Plains stream fish assemblage

Despite the importance of habitat in determining species distribution and persistence, habitat dynamics are rarely modeled in studies of metapopulations. We used an integrated habitat-occupancy model to simultaneously quantify habitat change, site fidelity, and local colonization and extinction rates for larvae of a suite of Great Plains stream fishes in the Arikaree River, eastern Colorado, USA, across three years. Sites were located along a gradient of flow intermittency and groundwater connectivity. Hydrology varied across years: the first and third being relatively wet and the second dry. Despite hydrologic variation, our results indicated that site suitability was random from one year to the next. Occupancy probabilities were also independent of previous habitat and occupancy state for most species, indicating little site fidelity. Climate and groundwater connectivity were important drivers of local extinction and colonization, but the importance of groundwater differed between periods. Across species, site extinction probabilities were highest during the transition from wet to dry conditions (range: 0.52-0.98), and the effect of groundwater was apparent with higher extinction probabilities for sites not fed by groundwater. Colonization probabilities during this period were relatively low for both previously dry sites (range: 0.02-0.38) and previously wet sites (range: 0.02-0.43). In contrast, no sites dried or remained dry during the transition from dry to wet conditions, yielding lower but still substantial extinction probabilities (range: 0.16-0.63) and higher colonization probabilities (range: 0.06-0.86), with little difference among sites with and without groundwater. This approach of jointly modeling both habitat change and species occupancy will likely be useful to incorporate effects of dynamic habitat on metapopulation processes and to better inform appropriate conservation actions.KEYWORDS: Stream fishes, Species occurrence, Great Plains, USA, Intermittent streams, Groundwater, Joint habitat occupancy modeling, Metapopulation

Headwater Streams and Wetlands are Critical for Sustaining Fish, Fisheries, and Ecosystem Services

Headwater streams and wetlands are integral components of watersheds that are critical for biodiversity, fisheries, ecosystem functions, natural resource-based economies, and human society and culture. These and other ecosystem services provided by intact and clean headwater streams and wetlands are critical for a sustainable future. Loss of legal protections for these vulnerable ecosystems would create a cascade of consequences, including reduced water quality, impaired ecosystem functioning, and loss of fish habitat for commercial and recreational fish species. Many fish species currently listed as threatened or endangered would face increased risks, and other taxa would become more vulnerable. In most regions of the USA, increased pollution and other impacts to headwaters would have negative economic consequences. Headwaters and the fishes they sustain have major cultural importance for many segments of U.S. society. Native peoples, in particular, have intimate relationships with fish and the streams that support them. Headwaters ecosystems and the natural, socio-cultural, and economic services they provide are already severely threatened, and would face even more loss under the Waters of the United States (WOTUS) rule recently proposed by the Trump administration

A comprehensive approach for habitat restoration in the Columbia Basin

The Columbia Basin once supported a diversity of native fishes and large runs of anadromous salmonids that sustained substantial fisheries and cultural values. Extensive land conversion, watershed disruptions, and subsequent fishery declines have led to one of the most ambitious restoration programs in the world. Progress has been made, but restoration is expensive (exceeding US $300 M/year), and it remains unclear whether habitat actions, in particular, can be successful. A comprehensive approach is needed to guide cost-effective habitat restoration. Four elements that must be addressed simultaneously are (1) a scientific foundation from landscape ecology and the concept of resilience, (2) broad public support, (3) governance for collaboration and integration, and (4) a capacity for learning and adaptation. Realizing these in the Columbia Basin will require actions to rebalance restoration goals to include diversity, strengthen linkages between science and management, increase public engagement, work across traditional ecological and social boundaries, and learn from experience.This is the publisher’s final pdf. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandfonline.com/loi/ufsh20#.VUEib2MywS

The natural wood regime in rivers

International audienc

The National Early Warning Score and its subcomponents recorded within ±24 hours of emergency medical admission are poor predictors of hospital-acquired acute kidney injury

YesBackground: Hospital-acquired Acute Kidney Injury (H-AKI) is a common cause of avoidable morbidity and mortality. Aim: To determine if the patients’ vital signs data as defined by a National Early Warning Score (NEWS), can predict H-AKI following emergency admission to hospital. Methods: Analyses of emergency admissions to York hospital over 24-months with NEWS data. We report the area under the curve (AUC) for logistic regression models that used the index NEWS (model A0), plus age and sex (A1), plus subcomponents of NEWS (A2) and two-way interactions (A3). Likewise for maximum NEWS (models B0,B1,B2,B3). Results: 4.05% (1361/33608) of emergency admissions had H-AKI. Models using the index NEWS had the lower AUCs (0.59 to 0.68) than models using the maximum NEWS AUCs (0.75 to 0.77). The maximum NEWS model (B3) was more sensitivity than the index NEWS model (A0) (67.60% vs 19.84%) but identified twice as many cases as being at risk of H-AKI (9581 vs 4099) at a NEWS of 5. Conclusions: The index NEWS is a poor predictor of H-AKI. The maximum NEWS is a better predictor but seems unfeasible because it is only knowable in retrospect and is associated with a substantial increase in workload albeit with improved sensitivity.The Health Foundatio

Competition between hatchery-reared and wild juvenile Chinook salmon

Abstract.-We conducted two types of experiments in the upper Sacramento River, California, to test the effects of hatchery-reared juvenile Chinook salmon Oncorhynchus tshawytscha on the emigration, growth, and survival of their wild counterparts. In 3 years of displacement experiments, emigration rates from 8-m 2 enclosures into downstream traps were similar between control enclosures that contained 40 wild fish and treatment enclosures to which 33 or 40 hatchery fish were also added. The mean number of wild fish in enclosures at the end of experiments differed by less than one fish between treatments and controls during all 3 years, indicating that hatchery fish prompted few wild fish to emigrate. In 2 years of competition experiments wherein fish could not emigrate, the enclosures contained wild fish (40 fish), wild fish plus hatchery fish (40 wild fish plus 33 or 40 hatchery fish), or wild fish at the same total density as the treatment with wild plus hatchery fish (73 or 80 wild fish). During 2001, survival and specific growth rates of wild fish were similar among treatments, probably because resources were not limiting. During 2002, survival was similar among treatments, but the mean specific growth rate was 0.008 g/d higher in the treatment with 40 wild fish than in the treatment with wild plus hatchery fish (95% confidence interval [CI], 0.005-0.011 g/d). These data indicated a negative effect on wild fish growth of adding hatchery fish. The specific growth rate in the high-density wild fish treatment was intermediate and 0.003 g/d higher than in the treatment with hatchery fish (95% CI, Ϫ0.0005 to ϩ0.006 g/d), providing some evidence that hatchery fish had a greater negative effect on wild fish growth than an equal density of wild fish did

Brassy minnow in Colorado plains streams: identification, historical distribution, and habitat requirements at multiple scales

January 2002.Final Report to: Colorado Water Resources Research Institute, Colorado State University; Colorado Division of Wildlife, Aquatic Non-game and Endangered Wildlife Program ... Memorandum of Understanding No. 312-99.Includes bibliographical references (pages 97-102).The brassy minnow (Hybognathus hankinsoni) has apparently declined in distribution and abundance in Colorado since the 1970s and was one of three plains fish species to be listed as threatened or endangered by the State of Colorado in 1998. Our research objectives were to determine the historic distribution and critical habitat requirements of brassy minnow. This information will aid fishery managers in efforts to locate suitable habitat and potentially restore the species to more of its native range, thereby precluding need for further listing. By correctly identifying the 134 museum collections of Hybognathus, we were able to clarify the historic distributions of the two species in Colorado and vicinity. The two species were historically sympatric (i.e., found together) in the lower South Platte, North Platte, Republican, and Smoky Hill river basins, whereas plains minnow was allopatric (alone) in the Arkansas River basin. Brassy minnow was allopatric in the Transition Zone tributaries of the upper South Platte and North Platte rivers and Lodgepole Creek