Wildlife Research Wildlife Research Society
Ecology, management and conservation in natural and modified habitats

Permanent marking in an endangered species: physiological response to hot branding in Steller sea lions (Eumetopias jubatus)

Jo-Ann Mellish A B C , Daniel Hennen B , Jamie Thomton B , Lisa Petrauskas A B , Shannon Atkinson A B and Don Calkins B

A School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK 99775, USA.

B Alaska SeaLife Center, 301 Railway Avenue, PO Box 1329, Seward, AK 99664, USA.

C Corresponding author: Email: joann_mellish@alaskasealife.org

Wildlife Research 34(1) 43-47 http://dx.doi.org/10.1071/WR06073
Submitted: 16 June 2006  Accepted: 19 December 2006   Published: 27 February 2007


Identification of individual animals is important in order to evaluate age-specific survival rates, onset of sexual maturity and reproductive rates in wildlife populations. Of the various methods available to researchers, hot branding is the most effective, although somewhat controversial, tool available. The physiological effects of hot-iron branding (n = 7) were assessed using temporarily captive juvenile Steller sea lions (Eumetopias jubatus) (n = 22). Sea lions showed statistically significant increases in white blood cell count, platelet levels, globulin and haptoglobin concentration up to two weeks after branding. No significant differences were found in serum cortisol levels. The changes in health parameters we saw after branding were consistent with minor tissue trauma and indistinguishable from baseline levels after 7–8 weeks.


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