Daily salivary cortisol levels in response to stress factors in captive common bottlenose dolphins (Tursiops truncatus): a potential welfare indicator

Observed effects of noise on marine mammals include: changes in vocalisations, respiration, swim speed, diving and foraging behaviour; displacement; avoidance; shifts in migration path; stress; hearing damage and strandings, but responses of marine mammals to noise can often be subtle and barely detectable ( Weilgart 2007 ). In order to detect the presence of stress responses in these situations, the endocrine response to stressors is assessed evaluating the hypothalamic-pituitary-adrenal (HPA) axis activity in dolphins and other cetaceans ( Wright and others 2007 , Amaral 2010 ). The objective of the present study was to assess the acute stress response to anthropogenic stressors in a group of common bottlenose dolphins (Tursiops truncatus). CABI MORMÈDE, P., ANDANSON, S., AUPÉRIN, B., BEERDA, B., GUÉMENÉ, D., MALMKVIST, J., MANTECA, X., MANTEUFFEL, G., PRUNET, P., VAN REENEN, C. G., RICHARD, S. & VEISSIER, I. ( 2007 ) Exploration of the hypothalamic-pituitary-adrenal function as a tool to evaluate animal welfare. Fisheries Science 64, 643-647 SUZUKI, M., UCHIDA, S., UEDA, K., TOBAYAMA, T., KATSUMATA, E., YOSHIOKA, M. & AIDA, K. ( 2003 ) Diurnal and annual changes in serum cortisol concentrations in Indo-Pacific bottlenose dolphins Tursiops aduncus and killer whales Orcinus orca. In: International Conference on Diseases of Zoo and Wild animals (IZW/EAZWV), Barcelona, Spain TSIGOS, C. & CHROUSOS, G. P. ( 2002 ) Hypothalamic-pituitary-adrenal axis, neuroendocrine factors and stress.