Table 1. Sample size (N), body weight (BW) and stable isotope ratio in muscle (δ¹³C and δ¹⁵N, ‰) and metal and metalloid concentrations in liver and kidney (mg/kg dry weight).

Species	No.	Age	Sex	BW (g)	δ15N	δ13C		Hg	Cd	Cr	Co	Ni	Cu	Zn	As	Pb
Northern fulmarF. glacialis	4	4Ad	1M & 2F & 1U	616.3 ± 56.9c)	13.0 ± 0.54a)	−21.0 ± 0.64	liver	24.5 ± 12.6a)	26.7 ± 11.3a)	0.15 ± 0.09	0.05 ± 0.01	0.06 ± 0.07	16.4 ± 3.60	135.2 ± 25.1a,b)	1.50 ± 1.76	0.06 ± 0.04
							kidney	7.69 ± 4.12a)	102.7 ± 31.7a,b)	0.32 ± 0.05	0.16 ± 0.04b)	0.80 ± 1.25b)	15.3 ± 1.76	148.6 ± 9.49a,b)	1.22 ± 1.06a,b)	0.38 ± 0.27
Thick-billed murreU. lomvia	4	1Ad & 3Ju	1M & 2F & 1U	1,066.0 ± 37.1a)	11.2 ± 0.98a,b)	−21.5 ± 1.86	liver	1.89 ± 1.75b)	12.7 ± 4.85b)	0.47 ± 0.24	0.09 ± 0.02	0.84 ± 0.76	18.0 ± 2.01	99.9 ± 21.0a,b)	0.34 ± 0.45	0.02 ± 0.01
							kidney	1.21 ± 0.88b)	27.4 ± 13.4a,b)	0.45 ± 0.21	0.12 ± 0.03b)	2.42 ± 3.53b)	17.1 ± 1.52	103.4 ± 9.46b,c)	0.33 ± 0.38b)	0.11 ± 0.06
Short-tailed shearwaterP. tenuirostris	24	14Ad & 8Ju & 2U	9M & 7F & 8U	510.2 ± 61.3d)	10.3 ± 0.74b,c)	−22.0 ± 1.27	liver	1.33 ± 0.66b)	6.06 ± 4.06b)	0.28 ± 0.32	0.11 ± 0.08	0.53 ± 0.74	21.5 ± 10.7	105.2 ± 32.8b)	0.69 ± 0.58	0.08 ± 0.08
							kidney	0.83 ± 0.40b)	43.4 ± 49.4b)	0.39 ± 0.21	0.18 ± 0.11b)	2.40 ± 3.79b)	22.9 ± 13.8	102.7 ± 20.5c)	0.60 ± 0.45b)	0.26 ± 0.35
Tufted puffinF. cirrhata	5	1Ad & 3Ju & 1 U	4M & 1F	840.8 ± 72.4b)	9.27 ± 1.01c,d)	−22.7 ± 0.36	liver	1.44 ± 0.33b)	36.0 ± 9.31a)	0.10 ± 0.03	0.13 ± 0.04	1.48 ± 1.03	24.4 ± 4.71	156.1 ± 21.1a)	1.80 ± 0.88	0.03 ± 0.01
							kidney	1.63 ± 0.41b)	114.4 ± 50.1a)	0.42 ± 0.12	0.53 ± 0.37a)	15.5 ± 6.40a)	22.9 ± 10.8	153.2 ± 40.9a)	1.53 ± 0.35a)	0.04 ± 0.03
Horned puffin F. corniculata	3	3Ad	2M & 1F	631.7 ± 78.2c)	7.02 ± 0.20d)	−23.4 ± 0.04	liver	1.63 ± 0.22b)	10.5 ± 5.30b)	0.45 ± 0.27	0.10 ± 0.02	0.79 ± 0.54	18.0 ± 2.62	103.6 ± 16.6a,b)	0.68 ± 0.85	0.03 ± 0.02
							kidney	2.50 ± 0.16b)	52.8 ± 36.4a,b)	0.31 ± 0.10	0.28 ± 0.13a,b)	3.76 ± 5.27b)	18.8 ± 4.09	120.9 ± 20.7a–c)	0.54 ± 0.55a,b)	0.17 ± 0.17

Different letters indicate significant differences among species (Tukey test, P<0.05). Ad: adult, Ju: juvenile, M: male, F: female, U: unidentified.