Table 2. The carbon to nitrogen ratio and stable isotope signatures of penguin chick feathers and nine common krill and fish prey species.
| Group, taxa or year | n | C/N | δ15N (‰) | δ13C (‰) |
| Chick feathers | ||||
| Chinstrap penguin, 2008 | 20 | 3.1±0.1 | 7.8±0.3a | −24.7±0.3a |
| Chinstrap penguin, 2009 | 20 | 3.1±0.1 | 7.5±0.3a | −25.2±0.3b |
| Gentoo penguin, 2008 | 20 | 3.1±0.1 | 8.9±0.6b | −24.6±0.3a |
| Gentoo penguin, 2009 | 21 | 3.1±0.1 | 9.8±0.8c | −24.3±0.3c |
| Prey library | ||||
| Krill, Euphausia superba | 40 | 3.7±0.2 | 3.3±0.6a | −26.4±1.4a |
| Fish, Protomyctophum bolini | 13 | 3.2±0.1 | 9.2±0.5 | −23.0±0.5 |
| Fish, Electrona antarctica | 41 | 3.3±0.1 | 8.8±0.7b | −25.5±0.7b |
| Fish, Gymnoscopelus nicholsi | 6 | 3.4±0.1 | 9.4±0.3bc | −22.6±0.8c |
| Fish, Notolepis coatsi | 3 | 3.2±0.1 | 7.2±0.8d | −25.7±0.4abd |
| Fish, Lepidonotothen squamifroms | 10 | 3.3±0.1 | 9.6±0.8c | −24.2±0.7d |
| Fish, Pleuragramma antarcticum | 30 | 3.4±0.2 | 9.4±0.5c | −24.7±0.4d |
| Fish, Trematomus newnesi | 10 | 3.3±0.1 | 8.2±0.5bd | −24.8±0.5bd |
| Fish, Champsocephalus gunnari | 5 | 3.3±0.1 | 8.5±0.3 | −25.1±0.3 |
Carbon to nitrogen ratios (C/N) and stable isotope values (δ15N & δ13C) are presented mean ± SD. Chick feathers and prey species that do not share at least one superscript within a column for each group (feathers or prey) are significantly different for the variable in question at the 0.05 level. P. bolini [45] and C. gunnari [44] were not included in prey species analyses.