Whales exhibit skin damage consistent with acute sunburn in humans, and it seems to be getting worse over time, reveals research published this week in Proceedings of the Royal Society B.
Scientists from the Zoological Society of London (ZSL), Queen Mary, University of London and CICIMAR, studied blue whales, fin whales and sperm whales in the Gulf of California to determine the effect of rising levels of ultraviolet radiation (UVR) on their health.
For a number of years scientists have observed blisters on the skin of whales. Now, using high-quality photos to give accurate counts of the blisters and analysing areas of damage in skin samples, this research has found that the three species of whale exhibit skin damage that is commonly associated with acute sunburn in humans.
Notably, the scientists also found that signs of sun damage were more severe in the paler-skinned blue whales, compared with the darker-skinned fin whales, and that in blue whales the symptoms of sunburn seem to be getting worse during the three years the study took place.
The UV index for the Gulf of California fluctuates between high and extremely high throughout the year. Lead author, Laura Martinez–Levasseur from ZSL and Queen Mary, says, "Whales need to come to the surface to breathe air, to socialise and to feed their young, meaning that they are frequently exposed to the full force of the sun.
"The increase in skin damage seen in blue whales is a matter of concern, but at this stage it is not clear what is causing this increase. A likely candidate is rising UVR as a result of either ozone depletion, or a change in the level of cloud cover."
Co-author Professor Edel O'Toole, from Queen Mary, says, "As we would expect to see in humans, the whale species that spent more 'time in the sun' suffered greater sun damage. We predict that whales will experience more severe sun damage if ultraviolet radiation continues to increase."
The next phase of the research will look at the expression of genes involved in the production of skin pigmentation and DNA damage repair and try to gain a greater understanding of the consequences of sun damage in whales.
Lead author Dr Karina Acevedo-Whitehouse, from ZSL says, "We have shown that exposure to strong sun is damaging to whales' skin. We now need to understand the knock-on effects and whether whales are able to respond quickly to increasing radiation by enhancing their natural sun-protection mechanisms."
Editors' notes
The paper 'Acute sun damage and photoprotective responses in whales' (DOI: 10.1098/rspb.20101903) will be published online in Proceedings of the Royal Society B on Wednesday 10 November. Advance copies of the paper are available from Daisy Barton at the Royal Society Press Office: 020 7451 2510 or daisy.barton@royalsociety.org
ZSL
Founded in 1826, the Zoological Society of London (ZSL) is an international scientific, conservation and educational charity: our key role is the conservation of animals and their habitats. The Society runs ZSL London Zoo and ZSL Whipsnade Zoo, carries out scientific research at the Institute of Zoology and is actively involved in field conservation overseas. For further information please visit www.zsl.org.
Queen Mary, University of London
Queen Mary, University of London is one of the UK's leading research-focused higher education institutions with some 15,000 undergraduate and postgraduate students. Amongst the largest of the colleges of the University of London, Queen Mary's 3,000 staff deliver world class degree programmes and research across 21 academic departments and institutes, within three sectors: Science and Engineering; Humanities, Social Sciences and Laws; and the School of Medicine and Dentistry.
Ranked 11th in the UK according to the Guardian analysis of the 2008 Research Assessment Exercise, Queen Mary has been described as 'the biggest star among the research-intensive institutions' by the Times Higher Education and also won the 'Most Improved Student Experience' award for 2009, reflecting the superb academic and social experience offered to all students at the College. The College has a strong international reputation, with around 20 per cent of students coming from over 100 countries.
Queen Mary has an annual turnover of £220 million, research income worth £61 million, and generates employment and output worth £600 million to the UK economy each year. As a member of the 1994 Group of research-focused universities, Queen Mary has made a strategic commitment to the highest quality of research, but also to the best possible educational, cultural and social experience for its students.
The College is unique amongst London's universities in being able to offer a completely integrated residential campus, with a 2,000-bed award-winning Student Village on its Mile End campus.
Website: http://www.qmul.ac.uk/
Twitter: http://twitter.com/QMUL
CICIMAR
The Interdisciplinary Marine Science Center (CICIMAR) is one of the leading Marine Research Institutions in Mexico. It is affiliated to the National Polytechnic Institute (IPN), the second most recognized Mexican University, and it offers postgraduate research programs in Marine Science and Natural Resource Management. At CICIMAR, close to 50 academics specialized in Fisheries, Marine Biology and Ecology, Aquaculture and Ocean Science conduct innovative research projects, long term monitoring studies and ecosystem modelling. These research projects involve over 100 postgraduate students annually. Its unique location along the coast of the Baja California Peninsula is strategic and ideal for sampling and monitoring the Gulf of California, an exceptionally diverse ecosystem. As a young research Center, of only 34 years since its foundation, it has graduated more than 500 students from Mexico and several Latin American Countries, many of which have received local and national awards. For further information visit http://www.cicimar.ipn.mx/oacis/