Diet of post-breeding Antarctic Shags Phalacrocorax bransfieldensis at Cockburn Island, Antarctic Peninsula
Authors
MARIANELA BELTRÁN1, GABRIELA TAVELLA2 & RICARDO CASAUX3,4
1Centro para el Estudio de Sistemas Marinos (CESIMAR-CENPAT, CONICET), Bv. Brown 2915, (9120) Puerto Madryn, Chubut, Argentina (mbeltran@cenpat-conicet.gob.ar)
2Secretaría de Turismo y Áreas Protegidas, Sarmiento 635, (9200) Esquel, Chubut, Argentina
3Centro de Investigación Esquel de Montaña y Estepa Patagónica (CIEMEP, CONICET-UNPSJB), Roca 780, (9200) Esquel, Chubut, Argentina
4Instituto Antártico Argentino, 25 de Mayo 1143, (1650) General San Martín, Buenos Aires, Argentina
Citation
BELTRÁN, M., TAVELLA, G. & CASAUX, R. 2017. Diet of post-breeding Antarctic Shags Phalacrocorax bransfieldensis at Cockburn Island, Antarctic Peninsula.
Marine Ornithology 45: 17
- 19
http://doi.org/10.5038/2074-1235.45.1.1194
Received 21 October 2016, accepted 25 October 2016
Date Published: 2017/04/15
Date Online: 2017/02/28
Key words: Antarctic Shag, post-breeding diet, Antarctica, demersal fish, regurgitated casts
Abstract
The diet of post-breeding Antarctic shags (Phalacrocorax bransfieldensis) was investigated at Cockburn Island, in the Antarctic Peninsula, through the analysis of pellets collected in February 2015. Demersal-benthic fish were the most frequent and important prey, followed by invertebrates. Among the fish, nototheniids were most abundant in the diet in terms of numbers, whereas channichthyids, Chionodraco rastrospinosus in particular, represented most of the mass. The information provided here differs from that reported for post-breeding individuals belonging to other shag species and for post-breeding Antarctic shags. This article discusses our results and the differences with previous studies, in terms of prey availability among localities.
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