MEPS 558:81-96 (2016)  -  DOI: https://doi.org/10.3354/meps11866

ABSTRACT: Species that home demonstrate faithfulness to a particular location; however, not all species with high site fidelity can or will home. These movement decisions are often mediated by a species’ social behaviour and habitat preferences. Here we explored how habitat specialisation, site fidelity and social traits relate to homing behaviour in 5 species of cardinalfish (family Apogonidae). We also compared species’ capacity to home across open water versus continuous reefscapes. To track site fidelity and then homing behaviour, the precise locations of over 1200 tagged cardinalfish on Kimbe Bay reefs (West New Britain, Papua New Guinea) were visually monitored over time. Following experimental displacement, all species homed quickly across ~400 m of both open water and continuous reef habitats. Incredibly, individuals of one species homed up to 5 km across multiple reef and inter-reef passages. Homing was not coupled with site fidelity, as both low and high fidelity species homed well. However, it was correlated with the degree of habitat specialisation, with specialist species returning in greater numbers than generalist species. Social traits alone did not predict stronger homing behaviours, but gregarious species with high site fidelity homed better than the less social and less specialised species. Hence, both social factors and habitat preferences appear to influence the propensity to home. Generalist species and those that do not form rigid social groups are more likely to be able to settle for new sites and have less need to return to precise locations.

KEY WORDS: Homing · Behaviour · Habitat specialisation · Aggregation · Coral reef fish · Social preferences · Apogonidae