Relating Habitat Use to Survival of Oncorhynchus in Rock Creek and the Clark Fork River

Westslope Cutthroat Trout Oncorhynchus clarkii lewisi (WCT) is a native trout species of conservation concern in Montana. Both migratory and resident life histories can be found in cutthroat from the same natal stream. Habitat degradation and hybridization with rainbow trout O. mykiss (RBT) have resulted in few genetically pure, migratory WCT populations persisting in large river systems. These WCT conservation populations are occurring more and more as isolated, resident populations in headwater streams. Rock Creek in Western MT has retained a unique population of migratory, non-hybridized WCT, and is of special conservation and ecological interest. As we work to protect WCT and migratory life histories, we need to better understand how these fish use habitats and how that habitat use may relate to subsequent survival. From 2018 to 2021, 80 of these WCT, along with 81 hybrids and 29 RBT had radio telemetry tags implanted to be tracked primarily for spawning migrations and habitat use. I used locations and mortality indicators from radio telemetry data collected over the course of the three-year study to examine how survival differed between fish with varied genetic ancestry and then examined whether there was a relationship between survival and habitat use. There was no significant difference in annual survival between different ancestries of Oncorhynchus spp. I combined all 190 fish in the study to examine the association between survival and habitat use. Fish spending the summer (June, July, and August) in Rock Creek showed much higher survival rates than those spending the summer in the Clark Fork River. I found major differences in the habitats in question, with substantially higher temperatures in the Clark Fork River versus Rock Creek, but are also correlated with lower flow and higher contaminant levels. Results of this study build a better understanding of how survival relates to habitat use and can be useful to help protect and prioritize habitats

Influence of the COVID-19 Pandemic on Clinical Trial Discontinuation in Anesthesiology: Cross-sectional Analysis

BackgroundThe COVID-19 pandemic drastically altered perioperative medical practice owing to safety concerns, postponing elective or nonemergent procedures, supply chain shortages, and reallocating perioperative staff to care for patients with COVID-19. However, the impact of the pandemic on the conduct on anesthesiology clinical research is unknown. ObjectiveThe primary objective was to quantify the magnitude of the COVID-19 pandemic’s impact on anesthesiology clinical research. MethodsWe performed a systematic search using ClinicalTrials.gov to identify clinical trials related to the practice of anesthesiology. We screened trials with status updates from January 1, 2020, through October 1, 2021, to capture trials potentially affected by the COVID-19 pandemic by the time of our search. Investigators screened for relevant studies and extracted trial characteristics along with the reason for discontinuation reported on the clinical trial registry. ResultsA total of 823 clinical trials met inclusion criteria, and 146 clinical trials were discontinued within the designated date range. In total, 24 (16.4%) of the 146 clinical trials were halted explicitly owing to the COVID-19 pandemic. A significant association existed between trial enrollment numbers and the likelihood of discontinuation due to the COVID-19 pandemic, as larger trials were more likely to be disrupted (z=–2.914, P=.004). ConclusionsThe COVID-19 pandemic is reportedly associated with the discontinuation of anesthesiology-related clinical trials. With the uncertain course of the COVID-19 pandemic, developing anesthesia trial protocols to help minimize social interaction and prevent premature trial disruption are imperative