Responses to acute sun exposure in large whales

Article By:

Martinez-Levasseur, Laura M. Department of Biology, Trent University, Peterborough, Ontario, Canada.

Gendron, Diane Centro Interdisciplinario de Ciencias Marinas, Instituto Politécnico Nacional, La Paz, México.

Knell, Robert J. School of Biological and Chemical Sciences, Queen Mary University of London, United Kingdom.

O’Toole, Edel A. Centre for Cutaneous Research, Blizard Institute of Cell and Molecular Science, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom.

Singh, Manuraj Centre for Cutaneous Research, Blizard Institute of Cell and Molecular Science, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, United Kingdom.

Bowman, Amy Institute of Cellular Medicine, Newcastle University, Newcastle, United Kingdom.

Birch-Machin, Mark Dermatological Sciences, Institute of Cellular Medicine, Newcastle University, Newcastle, United Kingdom.

Acevedo-Whitehouse, Karina Institute of Zoology, Zoological Society of London, United Kingdom; Unit for Basic and Applied Microbiology, School of Natural Sciences, Autonomous University of Querétaro, Santiago de Querétaro, México.

Last reviewed:2014

DOI:https://doi.org/10.1036/1097-8542.YB140801

Although there has been a net decrease of emissions of ozone-depleting substances (which are compounds that contribute to stratospheric ozone depletion, including chlorofluorocarbons and hydrofluorocarbons) in recent years, ozone loss occurs every year over the North Pole and South Pole, and large amounts of solar ultraviolet radiation (UV) continue to reach our biosphere. These high levels of UV represent a significant threat to the Earth's ecosystems, and there is now evidence that, as happens in humans, some wild species are developing UV-induced skin cancer. So far, the majority of published studies on the effects of UV on wildlife have focused on amphibians, fishes, and invertebrates, largely ignoring the effects on large marine mammals, which are unable to avoid continuous exposure to UV because of their physiological and life-history constraints. Indeed, whales spend extended periods of time at the ocean's surface to breathe and socialize, and they lack the epidermal protection that would be conferred by fur, feathers, or scales. Interestingly, reports of skin lesions in whales have increased in the last decade. Whereas the causes of some lesions have been identified [for example, tattoo skin disease (lesions in the form of black punctiform stippled patterns), caused by poxvirus], the causes of many others (for example, blister-type lesions) remain unknown. It is possible that the large amounts of UV reaching the oceans play a role in the development of these whales' lesions. Knowing that the levels of UV are not expected to change for several decades and that UV has been recognized as one of the most injurious environmental factors for marine ecosystems, it is pressing to investigate the extent of the damage to whales caused by UV.

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