Puffin beaks glow when exposed to ultraviolet light

British ornithologist Jamie Dunning at the University of Nottingham in England has shown that puffins have beaks which fluoresce under ultraviolet (UV) light. Dunning discovered that the the cere and lamella (the two yellow ridges on the puffin's beak) glow when exposed to ultraviolet light.

Image credit: Jamie Dunning

Responding to inquiries by Canadian media, he said that the discovery happened "by accident".

It's long been known that birds are able to see well into the ultraviolet range, due to the presence of short-wave sensitive opsins in their cone cells[1], and that ultraviolet florescence plays a role in mating rituals in certain species of birds. [2]. Moreover, in certain species of blackbird, females respond better to males with higher UV-reflection in their bills[3]

Dunning tweeted that when exposed to ultraviolet light, the puffin beaks lit up. Although scientists aren't yet sure what purpose this serves, Dunning wonders if this property was "related to signalling".

The ultraviolet fluorescence in the puffin beaks was originally observed in dead specimens, however Dunning also plans to observe live specimens. To this end, he collaborated with the Department of Design at the University of London to make "sunglasses" which will protect live puffins from UV light:

Image credit: Jamie Dunning / Department of Design, University of London

References:

[1]: Toomey, M.B. et. al., "A complex carotenoid palette tunes avian colour vision". Journal of The Royal Society
[2]: Barreira, A. S. et al., "Fluorescent and ultraviolet sexual dichromatism in the blue-winged parrotlet". Journal of Zoology.
[3]: Bright, A. and Waas, J. R. (August 2002). "Effects of bill pigmentation and UV reflectance during territory establishment in blackbirds". Animal Behaviour.