Table 2.
Bulk and compound-specific stable isotopic analyses of inter-specific differences of seabirds during the breeding season (based on red blood cell samples)
| Species | N | δ13C (‰) | δ15N (‰) | Trophic position | δ15N [Glx] (‰) | δ15N [Phe] (‰) |
|---|---|---|---|---|---|---|
| Gentoo penguin | 5 | − 17.1 ± 0.4b | 14.7 ± 0.1b | 3.7 ± 0.2a,b | 27.7 ± 1.5b | 7.5 ± 0.2b |
| Magellanic penguin | 5 | − 17.5 ± 0.4a,b | 14.3 ± 0.6a,b | 3.9 ± 0.1a | 26.2 ± 0.3b | 6.9 ± 0.8b |
| Rockhopper penguin | 5 | − 18.1 ± 0.6a | 13.6 ± 0.2a | 3.4 ± 0.1c | 23.3 ± 0.6a | 7.2 ± 0.9b |
| Thin-billed prion | 5 | − 19.8 ± 0.4c | 12.1 ± 0.9c | 3.5 ± 0.1b,c | 22.1 ± 1.1a | 5.4 ± 0.4a |
| ANOVA | F16,3 = 22.2, P < 0.001 | F16,3 = 31.0, P < 0.001 | F16,3 = 12.9, P < 0.001 | F16,3 = 19.4, P < 0.001 | F16,3 = 12.0, P < 0.001 |
Bulk stable isotope values δ13C and δ15N, trophic positions calculated from CSIA-AA and δ15N values of the trophic amino acid Glx (glutamic acid) and the source amino acid Phe (phenylalanine). Means and standard deviations are given, and homogenous subgroups according to post hoc tests (TUKEY) are marked by similar letters