Energetic constraints drive sex‐specific parental care in the monomorphic Leach's storm‐petrel <i>Hydrobates leucorhous</i>

Sex-specific parental care in dimorphic species may be unsurprising, but why this occurs monomorphic is more puzzling. To date, however, there have been few examinations of the causes phenomenon. Here, we evaluated possible explanations sex-specific provisioning Leach's storm-petrel Hydrobates leucorhous (until recently Oceanodroma leucorhoa). We tracked chick-rearing behavior 74 mated pairs using an automated nest monitoring system and collected daily measurements chick growth. found that males provisioned frequently made a larger overall contribution to feeding than females. Within-individual trip duration was variable for females, suggesting they were alternating greater degree between short, energetically taxing trips prioritize longer, recovery self-care. Moreover, females likely embark on longer after completing short encountering good condition. Males, appeared better able perform repeated resulted frequent as well amounts overall. These findings are consistent with explanation energetic constraints give rise male-biased, explain similar patterns other long-lived where adult survival high.