adUlt migrations | 71data were biased because a ring recovery is so much more likely on a
populated Brazilian beach – think Copacabana – than on a dusty Pata-
gonian shore. Secondly, the work identified a feeding area in the Gulf
Stream routinely used by shearwaters heading back to Wales.^24 This
area, about 1,000 km east of the coast of the Carolinas, had never been
suspected, let alone identified by traditional ringing.
Unusually, and in contrast to the Manx Shearwaters and indeed sev-
eral other species whose sigmoid track around the Atlantic makes full
use of following winds, Sabine’s Gulls adopt a relatively straight route
both southbound and northbound. When these elegant gulls head south
from their breeding station in north- east Greenland, they initially head
south before turning left to cross the Atlantic.^25 The gulls skirt but ap-
pear not to linger off the Grand Banks, the staging area used by Arctic
Terns and also Long- tailed Skuas^26 breeding in the same region of
Greenland. Instead Sabine’s Gulls press onward to a stopover area in the
Bay of Biscay and off Portugal. There they tarry for an average of 45 days
Modern devices have recorded migrations of Long- tailed Skuas between
breeding grounds of the High Arctic, north- east Greenland and Svalbard, and
wintering regions concentrated along the south- west coast of Africa.