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Abstract Objective This study investigated the drivers of Burbot Lota lota population decline in the Torrey Creek drainage, Wyoming, focusing on two primary stressors: predation by nonnative Brown Trout Salmo trutta and warming winter water temperatures that may limit successful recruitment. We aimed to (1) estimate annual rates of predation on Burbot by Brown Trout and (2) evaluate the combined effects of Brown Trout and increased winter temperatures on annual population growth and long-term viability of this cold-adapted species at the southwestern edge of its native range. Methods We conducted bioenergetics modeling and population simulations to assess Burbot vulnerability to Brown Trout predation in the Torrey Creek drainage. Brown Trout consumption of Burbot was estimated using Fish Bioenergetics 4.0 with temperature and diet data collected from 2020 to 2023. Deterministic and stochastic stage-structured population models were developed to evaluate Burbot population growth under varying predation and temperature scenarios. Demographic rates were informed by field data and the literature, and stochastic models incorporated uncertainty and environmental variability. Long-term projections assessed population growth (λ) and persistence over 100 years. Results Water temperatures during the Burbot embryogenesis period frequently exceeded 4°C in 2022 and 2023, reaching average daily benthic temperatures of 4.9°C in Torrey Lake and 4.5°C in Trail Lake during 2023. Bioenergetics modeling for the Torrey Creek drainage estimated that the Brown Trout population consumed 8–38 kg of Burbot annually. Deterministic models indicated positive Burbot population growth (λ = 1.12 under an observed scenario; λ = 1.02 under an increased predation scenario), with elasticity analyses showing survival across all stage classes as the most influential factors (elasticity = 0.28–0.33). Stochastic simulations without recruitment penalties projected Burbot persistence in 75% (observed) and 58% (increased predation) of iterations. However, when a reduction in recruitment due to water temperatures was modeled, persistence declined to 64% and 46%, respectively, with λ dropping below 1.0 in the increased predation scenario with a recruitment penalty occurring annually (λ = 0.98). Conclusions Our findings suggest that the Burbot population in the Torrey Creek drainage may be shifting toward a new, altered population dynamic characterized by elevated adult mortality and warming winter temperatures that challenge recruitment success. Predation by nonnative Brown Trout had a limited influence on overall Burbot population dynamics. Despite these stressors, Burbot population persistence appears likely, primarily sustained by adult survival. However, ongoing environmental changes and recruitment variability introduce uncertainty and potential risk over longer time scales. Continued monitoring and management may be necessary to ensure population resilience under future conditions.