Seabird makes citrusy bug repellant
Alaskan seabirds called crested auklets carry a citrus-smelling chemical in their feathers that could be one of the few examples ever found of a homegrown avian pest repellant.
Birds rub on themselves all kinds of substances alleged to repel pests, but biologists have found few species that grow their own chemical defenses, says Hector D. Douglas of the University of Alaska in Fairbanks. Such a substance has never turned up before in a seabird or in any bird that nests in big colonies.
Crested auklets forage in far northern waters, their thick, bright orange beaks contrasting with gray feathers. A distinctive forelock curves down between their eyes.
Auklet feathers contain a potentially repellant cocktail of organic compounds, Douglas and his colleagues report in the August Naturwissenschaften. Two of the components, octanal and hexanal, show up in insect-gland secretions known to repel predatory insects.
Such a substance might play a role in auklet mating, the researchers speculate. Its scent could give auklets a way to pick the least-parasite-prone partner, just by a whiff of his bug