Seasonal distribution and movement of juvenile Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) in the lower Saint John River Basin, New Brunswick, Canada

Juvenile Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) movement and distribution varies seasonally within the lower Saint John River Basin. We use acoustic telemetry to track coarse-scale movement and a network-based approach to develop metrics describing distribution and movement patterns ofjuvenile Atlantic sturgeon tagged in two rivers, the Saint John and Kennebecasis rivers. We use principal component analysis to develop indices of movement and residency and test for differences among seasons and between fish from each river. Juvenile Atlantic sturgeon exhibit higher residency during summer months compared with winter and spring. Juveniles are primarily concentrated in the brackish waters of the lower river reaches but make movements as far upriver as rkm 88. There was high variation in distribution and movement patterns exhibited by fish tagged in the Kennebecasis River, ranging from single-location occupancy to wide distribution. Three fish left the system during the study, indicating juveniles embark on brief marine excursions. Identifying spatiotemporal distributions of juvenile Atlantic sturgeon in their natal river systems is a crucial step towards identifying critical habitat and informing management decisions for this species.