stick or twist? | 137The most recent research on the Skomer Puffins has hinted that the
birds that reach the Mediterranean in late winter – either after remain-
ing in local waters or after venturing into the more distant Atlantic –
enjoy the highest breeding success the following summer. Acknowledg-
ing that flying taxes puffins, one interpretation is that only higher
quality birds, perhaps those with superior fishing skills and conse-
quently better body condition, can reach the distant Mediterranean.
Once there, they can benefit from a late winter spurt in marine pro-
ductivity. Returning to Skomer replenished, these high quality birds
are more likely to proceed to rear a chick than their lower- quality
neighbours.^10
While consistent habits are certainly a feature of seabirds’ lives, their
prominence can vary over time. For example a team under the aegis of
the Ascension Island Government studied frigatebirds on that island
in the tropical Atlantic, and amassed data from a mighty impressive 776
Ascension Frigatebird trips. Compared to trips in the hot season in the
early calendar months of the year, trips during the cool season, the lat-
ter calendar months, took the birds further from the colony, covered
more kilometres and lasted longer. They also showed less variation. Per-
haps feeding conditions were more benign during the hot season, allow-
ing the birds various options – hence variable trips.
Most consistency studies I have described concern adult birds. This is
simply for reasons of practicality; it is far easier to repeatedly handle an
adult bird at a colony than a youngster cruising the world’s oceans
during its years of immaturity. But this raises a very obvious question.
Do young birds leave the colony with their own personal set of quirks,
or are the early years spent trying various possibilities, in the manner of
a teenager causing angst for parents, before settling into the relative rut
of adulthood?
This is taxing to answer because of the difficulty of following birds in
detail through those ‘lost years’ of immaturity (Chapter 3). However, as
I write, there is no solid evidence that preference for particular foraging
sites is inherited, in contrast to preference for migratory directions,
which is almost certainly partly inherited from the bird’s parents in
many species. Another possibility is that the birds lacking consistent