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Synopsis The rapid environmental changes associated with the Anthropocene mean that flexible behavioral responses may be a critical determinant of animals’ resiliency to anthropogenic disturbance, particularly for species with long generation times and low vagility. One type of behavior that exemplifies this potentially important flexibility is parental care. Eggs and juvenile animals are sensitive to environmental stressors, and the ability of parents to adjust care behaviors to buffer their offspring from rapidly changing conditions may be critical to successful reproduction. In this study, we explore the role of parental care in buffering eggs from anthropogenic stressors in the long-lived, fully aquatic eastern hellbender salamander (Cryptobranchus alleganiensis alleganiensis). Using custom-designed infrared cameras installed in underwater artificial shelters in a natural stream, we describe hellbender paternal care behaviors in greater detail than has previously been possible, assess the extent to which hellbender fathers buffer their eggs from increasing levels of silt and decreasing concentrations of dissolved oxygen in nesting cavities, and describe the possible trade-offs that hellbender fathers exhibit between paternal care and self-maintenance behaviors. We found that while hellbender parents buffered their offspring from low dissolved oxygen concentrations by increasing parental care, there was an apparent trade-off between parental care and self-maintenance responses to low oxygen. Hellbender fathers did not show evidence of buffering their offspring from the effects of increasing silt or organic material in their nest cavities. We also found that filial cannibalism is a widespread behavior across nests, with almost all fathers exhibiting some cannibalism, although the extent varied widely. Our study indicates that hellbender parents may be able to reduce the impacts of declines in dissolved oxygen concentration on their offspring to a limited extent, but they may be unable to fully protect offspring from increasing silt.
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Adult survival probability and body size affect parental risk‐taking across latitudes
Abstract Parents faced with a predator must choose between their own safety versus taking care of their offspring. Each choice can have fitness costs. Life‐history theory predicts that longer‐lived species should be less willing than shorter‐lived species to return to care for their offspring after a predator disturbance because they have more opportunities to reproduce in the future. We increased adult predation risk during incubation for 40 bird species in north temperate, tropical, and south temperate latitudes. We found that species with higher adult survival probabilities were more cautious, waiting longer before returning to the nest to provide care. Contrary to other studies, we also found that parents were more risk averse and waited longer to return in smaller than larger species, likely reflecting greater vulnerability of smaller species. Ultimately, the relative risk a predator poses to a species and the probability of future reproduction predict parental risk taking across the world.
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- Award ID(s):
- 1656120
- PAR ID:
- 10455404
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ecology Letters
- Volume:
- 24
- Issue:
- 1
- ISSN:
- 1461-023X
- Format(s):
- Medium: X Size: p. 20-26
- Size(s):
- p. 20-26
- Sponsoring Org:
- National Science Foundation
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