Skip to main content
Log in

Living on the edge: thermoregulatory behaviour of South American sea lions, Otaria flavescens, at the northern limit of their Atlantic distribution

acta ethologica Aims and scope Submit manuscript

Abstract

Terrestrial reproduction presents a thermoregulatory challenge for marine mammals, especially in a context of global warming. Pinnipeds, especially otariids, differ from other marine mammals in that most reproductive processes occur on land. Rocky rookeries rarely provide thermoregulatory resources (shade, pools and wet sand), so pinnipeds reduce thermal stress through thermoregulatory behaviour such as flipper exposure, flipper movement and maintenance of individual distance. Our objective was to analyse climate correlates of thermoregulatory behaviour of Southern sea lions Otaria flavescens in a colony located at the warmest end of its northern distribution on the Atlantic coast of South America. We conducted summer behavioural observations of juveniles/sub-adult (less than 150 kg) and adult (300 kg) males in the Cabo Polonio rookery, Uruguay. Solar radiation and humidity were positively correlated with thermoregulatory behaviour of sea lions, while ambient temperature had a marginal effect and wind speed had no significant effect. There were no statistically significant differences between age classes in thermoregulation activity. These and previous results on thermoregulatory behaviour of pinnipeds open the possibility that pinnipeds can be limited in abundance or distribution if climate change alters solar radiation in terrestrial rookeries during the breeding season.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1

References

Download references

Acknowledgements

We thank Gonzalo Picasso, Director of Cabo Polonio National Park, for granting us all permissions for working and collecting the necessary data in the natural reserve. We also thank the rangers group and lighthouse keepers group of the park for the excellent treatment received.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Marcelo H. Cassini.

Ethics declarations

All applicable international, national and/or institutional guidelines for the care and use of animals were followed.

Conflict of interest

The authors declare that they have no conflict of interest.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Tuneu-Corral, C., Szteren, D. & Cassini, M.H. Living on the edge: thermoregulatory behaviour of South American sea lions, Otaria flavescens, at the northern limit of their Atlantic distribution. acta ethol 22, 67–71 (2019). https://doi.org/10.1007/s10211-018-0303-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10211-018-0303-x

Keywords

Navigation