Spawning migration, sex-specific home ranges, and seasonal site fidelity in a lacustrine population of Bowfin (Amia ocellicauda)

Abstract

Bowfin, Amia spp., are broadly distributed freshwater fishes native to eastern North America. Male bowfin build nuptial nests in the spring and provide parental care for eggs and young. Spawning occurs in or near wetland habitats often associated with larger bodies of water, but the literature suggests wider distribution during the growing season, such that annual movements may structure population and community dynamics. However, bowfin movements and their ecological roles are poorly known. Over 3 years, using radio telemetry, we studied movement patterns and home range size of the bowfin, Amia ocellicauda, in Oneida Lake, a large inland lake in New York State. We found female bowfin tended to range more widely than males. Furthermore, within-year structure in movement data and seasonal step-changes in relocations suggest that most bowfin exhibited migration-like movements to and from a primary spawning area in northwest Oneida Lake. After spawning (and for males, after parental care), bowfin dispersed around the western half of the lake, with some fish traversing the full extent of our study area. Analysis of home range sizes revealed high variability in how widely individuals roamed, but there was a significant tendency for females to exhibit larger home ranges than males during the spring. During the summer, there was a tendency for individual bowfin of both sexes to inhabit the same area in successive years, though males appeared to exhibit site fidelity more often than females. These data provide a new perspective on the movement ecology of bowfin.