Gannets are just like humans, Cornish scientists say. They spend their youth footloose and fancy free, and then settle down when they grow up.
In a study of northern gannets, researchers have shown that adults return to the same patch of sea over and over again to find food.
But younger gannets search far and wide and tend not to return to the same places – even if they find good hunting grounds.
The study also compared successful breeding adults with those which failed to breed, and found successful breeders stuck to their feeding grounds more reliably.
“It’s common for birds like gannets to return to the same foraging grounds year after year,” said Dr Stephen Votier, of the Environment and Sustainability Institute on Exeter’s Penryn Campus in Cornwall.
“They disperse widely at sea, and the fact that they return to specific areas is presumably linked to finding good foraging conditions.
“However, gannets don’t breed until they’re four or five years old, and our research shows that this tendency to return to favoured foraging grounds is lacking in birds younger than this.”
And, just like human adults whose kids have left home, adult gannets display renewed wanderlust after a breeding attempt has failed.
The research team studied gannets on the Welsh island of Grassholm, supported by the RSPB, and used precision GPS loggers to track birds.
The paper, published in the journal Proceedings of the Royal Society B, is entitled: “Effects of age and reproductive status on individual foraging site fidelity in a long-lived marine predator.”
