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Atlantic Sturgeon Acipenser oxyrinchus, a federally endangered anadromous fish, persist along the East Coast of North America. Despite two decades of federal protection, many populations have yet to fully recover and major knowledge gaps remain, especially in the southern portion of the species’ range. The seasonal movement patterns of river‐resident juveniles (RRJs) are not well understood, and little is known about the transition from the RRJ life stage to the marine‐migratory juvenile (MMJ) life stage. During the summers of 2014–2016 we captured and acoustically tagged age‐1 RRJ Atlantic Sturgeon in the Ogeechee, Altamaha, and Satilla rivers, Georgia, to (1) describe and quantify seasonal movements of RRJ Atlantic Sturgeon in order to identify important estuarine nursery areas and (2) examined temporal patterns of out‐migration in order to better understand the critical transition from RRJ to MMJ in Georgia rivers. Movements of 79 fish were monitored using an array of stationary receivers deployed downstream from the heads of tide in each river system. During the summer months in each river, the fish congregated in upriver, freshwater reaches, but during the winter months they moved downriver and became more broadly distributed. Some fish (36.7%; n = 29) migrated back up their natal river in the spring and remained there as age‐2 RRJs. We observed the out‐migration of 30.4% (n = 24) of age‐2 MMJs only during December–March, based on detections outside their natal river. The results of this study support the assumption of the closure of age‐1 populations that underpins recent quantitative studies of Atlantic Sturgeon recruitment.

Strand-feeding is a unique foraging technique used by Atlantic bottlenose dolphins ( Tursiops truncatus (Montagu, 1821)) in salt marshes of the southeastern USA wherein a group of dolphins rushes a creek bank, temporarily stranding themselves to capture fish that have been pushed ashore by their bow wave. Wading birds are attracted to these events to forage on stranded fish. We hypothesized that birds foraging in association with dolphins experience greater foraging efficiency than birds foraging away from dolphins and that some birds are able to meet their entire daily metabolic needs by foraging at strand-feeding events. The species composition, abundance, and foraging success of birds at 569 strand-feeding events were compared with the same parameters from marsh surveys of birds not associated with dolphins. Only Great Egrets ( Ardea alba L., 1758) were proportionately more common at strand-feeding events than in the marsh overall (p < 0.001). During peak strand-feeding hours, energy intake per hour was higher for Great Egrets foraging with strand-feeding dolphins than for birds foraging away from dolphins (p = 0.04). Bioenergetic models indicated that prey intake by Great Egrets at strand-feeding events was sufficient to meet their existence and likely their active metabolic requirements.