Table 1 Delipidated or normalized plasma δ¹³C and raw plasma δ¹⁵N values of albatrosses, giant petrels, and penguins breeding at Marion Island, which were tracked simultaneously with GPS data loggers during 2015–2018. Number of individuals indicates number of birds with tracks and corresponding stable isotopic values. Number of tracks indicates number of tracks used to estimate mean foraging locations as multiple tracks were recorded for brooding individuals (See Materials and Methods). Values given as mean ± SD (range)

32

32

1.0 ± 0.0 (1; 1)

−20.7 ± 1.5 (−23.6; −18.4)

14.0 ± 1.0 (12.1; 15.5)

28

36

1.3 ± 0.5 (1; 2)

− 20.2 ± 1.0 (−22.0; − 18.5)

11.4 ± 0.4 (10.4; 12.4)

22

36

1.6 ± 0.7 (1; 3)

−20.8 ± 0.7 (− 22.2; − 19.8)

12.0 ± 0.4 (11.4; 13.1)

27

29

1.1 ± 0.3 (1; 2)

−19.8 ± 1.2 (− 22.7; − 17.1)

14.4 ± 0.8 (12.7; 15.9)

23

25

1.1 ± 0.3 (1; 2)

−22.7 ± 0.5 (− 23.6; − 21.8)

12.8 ± 0.4 (12.3; 13.4)

17

26

1.5 ± 0.9 (1; 4)

− 21.7 ± 0.6 (− 23.2; − 20.9)

10.2 ± 0.5 (9.5; 11.4)

18

29

1.6 ± 0.8 (1; 3)

−22.3 ± 0.2 (− 22.7; − 22.0)

8.8 ± 0.3 (8.0; 9.2)

9

19

2.1 ± 1.1 (1; 4)

−22.6 ± 0.2 (− 22.9; − 22.1)

8.6 ± 0.4 (7.7; 9.1)