Title Intra-seasonal variation in foraging behavior among Adelie pengiuns Cape Hallett, Ross Sea, Antarctica
Author Lyver, P.O.; MacLeod, C.J.; Ballard, G.; Karl, B.J.; Barton, K.J.; Adams, J.; Aimley, D.G.; Wilson, P.R.
Author Affil Lyver, P.O., Landcare Research, Lincoln, New Zealand. Other: PRBO Conservation Science; University of Auckland, New Zealand; U. S. Geological Survey; H.T Harvey and Associates
Source Polar Biology, 34(1), p.49-67. Publisher: Springer-Verlag, Berlin, Germany. ISSN: 0722-4060
Publication Date Jan. 2011
Notes In English. Includes appendices. 98 refs. GeoRef Acc. No: 308834
Index Terms Antarctica; Southern Ocean--Ross Sea; Arthropoda; Aves; behavior; Cape Hallet; Chordata; Crustacea; diet; ecology; feeding; habitat; ice; ice cover; ice cover distribution; ice cover thickness; Invertebrata; Mandibulata; Neornithes; Ross Sea; sea ice; seasonal variations; Southern Ocean; Sphenisciformes; Tetrapoda; Vertebrata
Abstract We investigated intra-seasonal variation in foraging behavior of chick- rearing Adelie penguins, Pygoscelis adeliae, during two consecutive summers at Cape Hallett, northwestern Ross Sea. Although foraging behavior of this species has been extensively studied throughout the broad continental shelf region of the Ross Sea, this is the first study to report foraging behaviors and habitat affiliations among birds occupying continental slope waters. Continental slope habitat supports the greatest abundances of this species throughout its range, but we lack information about how intra-specific competition for prey might affect foraging and at-sea distribution and how these attributes compare with previous Ross Sea studies. Foraging trips increased in both distance and duration as breeding advanced from guard to creche stage, but foraging dive depth, dive rates, and vertical dive distances travelled per hour decreased. Consistent with previous studies within slope habitats elsewhere in Antarctic waters, Antarctic krill (Euphausia superba) dominated chick meal composition, but fish increased four-fold from guard to creche stages. Foraging-, focal-, and core areas all doubled during the creche stage as individuals shifted distribution in a southeasterly direction away from the coast while simultaneously becoming more widely dispersed (i.e., less spatial overlap among individuals). Intra-specific competition for prey among Adelie penguins appears to influence foraging behavior of this species, even in food webs dominated by Antarctic krill.
URL http://hdl.handle.net/10.1007/s00300-010-0858-0
Publication Type journal article
Record ID 91245