Volume 46, No. 2

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Foraging patterns of the Antarctic Shag Phalacrocorax bransfieldensis at Harmony Point, Antarctica


1Instituto Antártico Argentino, Av. 25 de Mayo N° 1143 (1650) General San Martín, Buenos Aires, Argentina
2Centro de Investigación Esquel de Montaña y Estepa Patagónica (CONICET-UNPSJB), Roca 780, 9200 Esquel, Chubut, Argentina


CASAUX, R. & BERTOLIN, M.L. 2018. Foraging patterns of the Antarctic Shag Phalacrocorax bransfieldensis at Harmony Point, Antarctica. Marine Ornithology 46: 169 - 175

Received 11 June 2018, accepted 26 July 2018

Date Published: 2018/10/15
Date Online: 2018/8/30
Key Words: Cormorants, feeding effort, South Shetland Islands, ecosystem monitoring


During the 1995 and 1996 summer seasons, the foraging patterns of the Antarctic Shag Phalacrocorax bransfieldensis were studied by direct observation at Harmony Point, Nelson Island, South Shetland Islands. During pre-laying and incubation, individuals of both sexes usually foraged once a day—females early in the morning and males when their partners returned to their nests. Due to increasing energy requirements at the nest, rearing individuals increased the daily time invested in foraging activities, displaying more—but shorter—foraging trips. The reduction in the duration of the foraging trips through the breeding season suggests that Antarctic shags budget their activities to buffer variable food abundance or energy requirements at their nests. Here, we discuss the possibility of using the foraging parameters measured in this study in ecosystem monitoring programs.


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