A SIX-YEAR study by Oxford University at Skomer Island has provided a new insight into puffin behaviour and migration.
The popular pint-sized sea bird can be found in large numbers on the Wildlife Trust’s island off the Pembrokeshire coast and research has found that those partnered pairs that follow similar migration routes breed more successfully the following season.
Many long-lived birds, such as swans, albatrosses or indeed, puffins, are known for their long-lived monogamous, ‘soulmate’ pairings.
Scientists have long understood that in these species, reproductive performance is influenced by pair bond strength and longevity, with long-established pairs usually better at rearing offspring.
However, in species like puffins which have to migrate to distant wintering grounds during the non-breeding season, very little is known about how mates maintain their pair-bond and behave.
The new study which features in April’s edition of Marine Ecology Progress Series, focused on whether puffin pairs stayed in contact during the winter months or instead headed off and migrated independently, prioritising their individual health and wellbeing. The research also establishes whether this approach had any impact on the pairs’ subsequent breeding success.
A team from Oxford’s Department of Zoology, in collaboration with the London Institute of Zoology, used miniature tracking devices called geolocators to track the migratory movements and behaviour of 12 pairs of Atlantic puffins, breeding on Skomer.
A key finding of the study is that pairs which followed more similar migration routes bred earlier and more successfully the following spring, showing that there is a clear benefit for puffins to migrate close to their mates.
Female puffins were found to forage more than males, proving critical to their breeding success the following season. Female puffins that foraged more over winter were able to lay eggs earlier and rear pufflings more successfully, most likely because they were in a better pre-breeding condition.
Lead author of the study Dr Annette Fayet, said: “While migrating close to one’s partner leads to more successful breeding in puffins, female winter foraging effort seems to be even more critical to ensure high reproductive success.
“Until recently tracking devices were too big to use on small birds like puffins. The recent miniaturisation of tracking technology mean we can now study the at-sea movements of puffins and other small migratory seabirds remotely over months and even years.”