Conservation aquaculture has prevented extirpation of Upper Columbia River white sturgeon Acipenser transmontanus, but uncertainty remains on how hatchery-origin fish move between habitats located within Canada and the United States. We describe how core and home ranges of sturgeon varied by environmental (country, season) and biological (age, sex, size) factors and determined residence at important habitats. Core range represented areas where individuals spent the majority of their time while home range represented most areas occupied. Fidelity to specific habitats was high, with home ranges averaging 10 km2 and 50% of individuals occupied the same core range across their entire detection period. Only 12% of individuals had home ranges encompassing both countries. Core and home ranges were larger during the summer compared to winter and larger within the United States compared to Canada. Larger (>120 cm) sturgeon had increased core and home ranges. We documented spawning capable hatchery-origin males and confirmed their residence at spawning sites when spawning was detected. Results improve our understanding of species biology and directly inform adaptive management of population recovery.
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