94 | Chapter 5
we can only marvel at a 45 g bird that, in the course of a 6- day off- duty
spell, travels a circuit of 2,660 km and reaches an average maximum
distance of 1,090 km from the colony. That is sufficient to take the birds
into deep oceanic waters south of Newfoundland’s Grand Banks.^11
As expected the shift lengths of the albatrosses are longer, typically
7– 20 days, with the all- time endurance record held by a Laysan Albatross
which sat, presumably stoically, for 58 days. Satellite tracking has re-
vealed the distances travelled by albatrosses when off duty. These range
from mostly no more than 300 km by Macquarie Island’s Black- browed
Albatrosses, to an unremarkable 1,200 km attained by South Georgia
Grey- headed Albatrosses, to a more impressive 2,400 km achieved by
Laysan Albatrosses breeding in the north- western Hawaiian Islands.
The difference in distances at least partly arises from the differences in
productivity of the regions. Albatrosses nesting on South Georgia have
productive waters close at hand allowing rapid replenishment,^12 while
the Laysan Albatrosses nesting in the far north- west of the Hawaiian
chain have to traverse barren local seas before feeding in more nourish-
ing regions in an arc north- west to north- east of the colony.
Arguably the most impressive forays during incubation are under-
taken by the mid- sized petrels and shearwaters. Take the case of the
Great Shearwaters nesting in literal millions on Nightingale Island and
Inaccessible Island next door to Tristan da Cunha in the central South
Atlantic. As permanent evidence of their abundance on these islands I
recall rocks that are visibly scoured. For millennia they have been scraped
by the birds’ sharp claws when the 800 g shearwaters scramble for a
take- off point above the tussocky vegetation. Once on the wing, eight
satellite- tagged males, taking their first break from incubation, pro-
vided track- data to Robert Ronconi.^13 Four headed south, up to 1,500 km
from the colony, and four headed west, approaching the east coast of
South America 4,000 km from the colony. Thus these shearwaters with a
body plucked of feathers, barely bigger than a standard jam jar, attained
a mean distance from the colony of about 2,500 km.
The longest journeys yet recorded by any albatross or petrel are those
undertaken by one of my favourite birds, Murphy’s Petrel, a species
already met. Velvety grey of plumage and docile of temperament, they
are the size of a small gull. They nest on the ground amid low scrubby