Far From Land The Mysterious Lives of Seabirds

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Only in the 1990s was it realised that parent albatrosses and petrels

feeding their chicks may alternately embark on short feeding trips last-

ing 1– 3 days and longer trips lasting over about five days. This habit has

proven widespread, but not universal. It can entail a simple alternation

of short and long trips, or a more complex pattern, the parent making

2– 5 short trips before embarking on a long one. In general, the short

trips result in a greater rate of food delivery to the chick, but at a cost to

the parent. The parents lose weight which is regained on the long trips.

The distribution of male (map A: 8 trips) and female (map B: 9 trips) Black- browed

Albatrosses tracked from South Georgia during incubation is clearly different. However,

during the brood- guard stage at the start of chick- rearing, the trips are much shorter and

barely differ between males (map C: 14 trips) and females (map D: 8 trips). Reproduced

with permission of The Royal Society, from the work cited in Note 19, Chapter 5.

60° W

60° W

30° W

30° W

60° S

45° S

60° W

60° W

30° W

30° W

60° S

45° S

60° W

60° W

30° W

30° W

60° S

45° S

60° W

60° W

30° W

30° W

60° S

45° S

0° E 0° E

Brood − guard : males (n = 14 birds, 14 trips) Brood − guard : females (n = 8 birds, 8 trips)

Incubation : males (n = 8 birds, 8 trips) Incubation : females (n = 9 birds, 9 trips)

AB

CD