Springs and spring-influenced streams (SSIS) in aridland riverscapes support endemic faunas, yet these ecosystems are threatened by groundwater extraction, climate disruption, and invasive species. San Felipe Creek in South Texas, USA, is fed by the third largest spring complex in the state, harbors several endemic and threatened fishes, and has been invaded by suckermouth armored catfish, Hypostomus species. Our objective was to use this prototypical aridland SSIS to characterize the roles spring influence (e.g., longitudinal distance from springs, temperature stability) versus traditional mesohabitat characteristics (e.g., depth, velocity, substrate, vegetation cover) play on the occupancy of eight fishes among seasons. These focal species included six native fishes, one temperate invasive fish, and one tropical invasive fish. To quantify these alternate habitat associations, we established 36 ten-meter-long transects representing pool, run, and riffle habitats and distributed along a 5-km longitudinal continuum of spring proximity. Next, we performed snorkel counts of fishes at these transects on four consecutive days and measured habitat variables and thermal regimes in January, March, August, and November of 2024. We then used multi-season occupancy models and information theoretic model selection to quantify the influence of environmental covariates on detection and occupancy. Across the eight focal species, detection probability (p) ranged from 0.18 for Notropis megalops to 0.61 for Astyanex mexicanus and occupancy (psi) from 0.23 for Notropis megalops to 0.50 for Micropterus salmoides. Occupancy was more strongly affected by spring proximity than mesohabitat factors for three of the eight species whereas season had a lesser effect on occupancy. Notably, occupancy of the endemic Etheostoma grahami decreased with distance from springs. These findings provide insight into the environmental filtering mechanisms driving fish community assembly in aridland SSIS and offer a quantitative baseline for future monitoring and conservation planning in the face of anthropogenic environmental changes.