Like mother like daughter: northern elephant seals exhibit fine-scale philopatry

Abstract Natal philopatry, the practice of a mother reproducing in the same region as her natal site, has been documented in numerous species. Studies on marine mammal philopatry have primarily focused on cross-colony scales, leaving a knowledge gap for fine-scale philopatry within colonies. We sought to identify the rate of fine-scale natal philopatry in northern elephant seals, sustained site fidelity across years, and additional drivers of site selection during the breeding season. Using 20 years of mark-recapture data collected from the ~3200-m long Año Nuevo colony in northern California, we discovered high rates of fine-scale philopatry, with females pupping an average of 395 m from where they were born. Females producing pups showed high site fidelity to the site of their first pup production, although the correlation was not as strong as to their natal site. Our results have implications for within-colony genetic connectivity and generational shifts in breeding sites influenced by coastal erosion.