Diving behaviour of the grey-headed albatross
Foraging grey-headed albatrosses spent 86% of the night but only 20% of the day sitting on the sea; most diving activity occurred during daylight. During the broad-guard period of nesting, peaks of diving activity occurred at midday and dusk. During the subsequent chick-rearing period, however, divi...
Published in: | Antarctic Science |
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Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
1997
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Subjects: | |
Online Access: | http://dx.doi.org/10.1017/s0954102097000321 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102097000321 |
Summary: | Foraging grey-headed albatrosses spent 86% of the night but only 20% of the day sitting on the sea; most diving activity occurred during daylight. During the broad-guard period of nesting, peaks of diving activity occurred at midday and dusk. During the subsequent chick-rearing period, however, diving was mainly at dawn and dusk. Of 485 dives measured, the depth averaged 0.74 m, with maximum depth at 6.5 m. On average grey-headed albatrosses dived 24 times during a five day foraging trip. Dive depths increased towards midday, probably as a function of the birds' visual acuity rather than due to vertical migration of their prey. We estimate that grey-headed albatrosses may obtain 30–45% of their daily food requirements by diving. |
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