Individual energy demands constrain survival and growth that determine population level performance ultimately driving geographic range limits. Differences in species traits like behavior and thermal physiology affect energy demands and therefore drive interspecific differences in the aforementioned performance metrics. We tested two hypotheses for four fishes in the Appalachian Mountains of the Southeastern USA: 1) pelagic species have higher energy demands and therefore higher consumption rates relative to benthic species and 2) high-elevation species exhibit a distinct thermal niche adaptation compared to low-elevation species. This distinction could either be (a) thermal adaptation, resulting in high-elevation species having lower thermal optimum than low-elevation species or (b) countergradient variation, resulting in high-elevation species having higher consumption rates across temperatures due to increased thermal sensitivity in comparison to low-elevation species. We performed consumption experiments in the laboratory at temperatures from 8 to 32°C to address these hypotheses. We found lower energy demands for benthic versus pelagic species across all temperatures. As example, pelagic species consumed mean 2,308 J/g/d at 28°C whereas benthic species consumed mean 625 J/g/d at the same temperature, supporting Hypothesis 1. High and low-elevation pelagic species had the same optimum temperature for consumption (28°C) while no clear optimum was present for benthic species, not supporting Hypothesis 2a. However, high-elevation species had lower consumption rates at warm temperatures for both habitat guilds, supporting Hypothesis 2a and refuting Hypothesis 2b. These findings provide evidence for thermal adaptation and emphasize distinctions in energy demands between habitat guilds and elevational ranges to inform conservation planning.