Intercept Telemetry of the Hudson River Striped Bass Resident Contingent: Migration and Homing Patterns

Abstract

Hudson River striped bass Morone saxatilis show highly variable migration patterns, as observed through past tagging studies and otolith microchemical analyses. Recent studies have shown resident, estuarine, and ocean migratory contingents in the Hudson River. We undertook a directed study to more precisely characterize the seasonal migrations of the resident contingent. Remote biotelemetry was conducted on 12 resident striped bass during a 14-month period in 2004–2005. All tagged striped bass migrated downriver from October 2004 to January 2005 and returned upriver from March to May 2005. Observed seasonal migration patterns were similar to those expected from previous tagging and otolith microchemistry studies: Directed downriver emigration to brackish-water overwintering habitats was followed by upriver migration to spring–summer freshwater feeding and spawning habitats. Eight of 12 fish showed directed spring migrations upriver to their original tagging site and were repeatedly located there, indicating strong homing behavior and residence. These very specific patterns of homing indicate that local-scale effects (e.g., fishing, pollution) can have persistent effects on components of the Hudson River striped bass population.