Supplementary Material Table 1 References References: [1] Mill (2007); [2] Miller (1980); [3] Hernaman et al. (2009); [4] Sano et al. (1984); [5] Frederich et al. (2009); [6] Alwany et al. (2005); [7] Ho et al. (2007); [8] Kuo & Shao (1991); [9] Hata &Umezawa (2011); [10] Carassou et al. (2008); [11] Allen, (1991); [12] Gerber & Marshall (1974); [13] Pratchett et al.(2001); [14] Hobson & Chess (1978); [15] Marnane & Bellwood (2002); [16] Kulbicki et al. (2005); [17] Griffiths et al. (2009); [18] Randall (1978); [19] Hiatt & Strasburg (1960); [20] Fishelson & Sharon (1997); [21] Haight et al. (1993); [22] Holmes & McCormick (2010); [23] Chen et al. (2001); [24] Saito et al. (1999); [25] Griffiths et al. (2007); [26] Choat et al. (2002); [27] Choat et al. (2004); [28] Depczynski & Bellwood (2003); [29] Patton (1994); [30] Cole et al. (2010) Allen GR (1991) Damselfishes of the world. 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Biosci Biotechnol Biochem 63:2028-2030 Sano M, Shimizu M, Nose Y (1984) Food habits of teleostean reef fishes in Okinawa Island, southern Japan. University of Tokyo Press, Tokyo, Japan Supp. Figure 1: Non-metric Multi-Dimensional Scaling (nMDS) plots of fish tissue C and N composition (Euclidean Distances based on normalised δ15N, δ13C and C:N). Compositions did not display any significant differences between seasons (pseudo-F[2,271]=1.49, p(perm)=0.242) but varied significantly between (a) zones (pseudo-F[5,271]=7.33, p(perm)<0.01) and (b) trophic groups (pseudo-F[3,271]=6.90, p(perm)<0.05). There was high correlation (>0.80) between tissue parameters, δ15N (d15N), δ13C (d13C) and C:N, and the nMDS based on Pearson correlation coefficients (shown with gray lines in b). Supp. Table 1: The fatty acid (FA) composition (%) of fishes collected during May 2008 differed significantly for carnivores between the Deep reef slope and Lagoon (pseudo-F[1,6]=80.6, p(perm)<0.05), and for Stegastes fasciolatus and Abudefduf sexfasciatus between the reef slope and reef flat (pseudo-F[1,8]=2.87, p(perm)<0.05 and pseudo-F[1,4]=7.19, p(perm)<0.05, respectively). ‘Influential’ FAs showing high correlation (>0.90) with normalised between-sample similarities are shown in bold. Data are mean ± s.e. and the number of samples is shown in parentheses for each zone. FA Carnivores Stegastes fasciolatus Reef slope Reef flat (7) (3) Abudefduf sexfasciatus Reef slope Reef flat (2) (4) 0.00 ± 0.0 0.04 ± 0.0 0.00 ± 0.0 0.00 ± 0.0 0.00 ± 0.0 2.32 ± 0.6 2.21 ± 0.5 0.44 ± 0.1 Deep reef slope (7) Lagoon (4) 0.05 ± 0.1 Saturated C13:0 C14:0 0.72 ± 0.2 0.69 ± 0.0 0.94 ± 0.2 C15:0 C16:0 0.36 ± 0.1 14.47 ± 3.0 0.51 ± 0.0 14.50 ± 0.4 0.22 ± 0.0 24.69 ± 1.2 0.40 ± 0.1 28.43 ± 1.8 0.21 ± 0.0 28.34 ± 1.9 0.11 ± 0.0 23.61 ± 1.1 C17:0 0.97 ± 0.1 0.98 ± 0.0 0.46 ± 0.0 0.64 ± 0.3 0.22 ± 0.0 0.31 ± 0.0 8.51 ± 0.6 0.29 ± 0.0 6.66 ± 0.9 9.38 ± 0.2 0.31 ± 0.0 0.36 ± 0.0 C18:0 7.33 ± 2.3 8.90 ± 2.0 C19:0 0.49 ± 0.1 0.33 ± 0.0 8.96 ± 0.5 0.33 ± 0.0 C20:0 0.25 ± 0.0 0.32 ± 0.0 0.29 ± 0.0 0.31 ± 0.1 0.20 ± 0.0 0.36 ± 0.0 C21:0 0.51 ± 0.2 0.34 ± 0.2 0.04 ± 0.0 0.08 ± 0.0 0.00 ± 0.0 0.04 ± 0.0 0.52 ± 0.2 0.06 ± 0.0 0.00 ± 0.0 0.11 ± 0.0 0.00 ± 0.0 0.05 ± 0.0 C22:0 0.34 ± 0.1 0.41 ± 0.0 C23:0 0.40 ± 0.2 0.65 ± 0.1 0.16 ± 0.1 0.05 ± 0.0 C24:0 0.32 ± 0.1 0.19 ± 0.0 0.27 ± 0.0 0.19 ± 0.0 0.13 ± 0.0 0.20 ± 0.0 i-C15:0 0.39 ± 0.1 0.16 ± 0.0 0.04 ± 0.0 0.07 ± 0.0 0.00 ± 0.0 0.00 ± 0.0 i-C16:0 0.28 ± 0.1 1.26 ± 0.3 0.05 ± 0.0 0.05 ± 0.0 0.03 ± 0.0 0.00 ± 0.0 i-C17:0 0.39 ± 0.2 1.40 ± 0.4 0.35 ± 0.0 0.27 ± 0.1 0.63 ± 0.2 0.29 ± 0.0 i-C18:0 0.65 ± 0.2 2.53 ± 0.6 0.39 ± 0.0 0.33 ± 0.0 0.65 ± 0.3 0.29 ± 0.0 1.30 ± 0.3 1.93 ± 0.2 2.02 ± 0.4 3.86 ± 0.3 9.04 ± 4.0 1.94 ± 0.2 Branch-saturated Monounsaturated C16:1 n-7 Carnivores Deep reef slope (7) Lagoon (4) i-C17:1 0.75 ± 0.1 0.37 ± 0.2 Stegastes fasciolatus Reef slope Reef flat (7) (3) 0.13 ± 0.0 0.09 ± 0.0 C17:1 n-7 1.06 ± 0.2 0.66 ± 0.1 0.64 ± 0.1 0.32 ± 0.1 C18:1 n-12 3.37 ± 1.5 0.34 ± 1.3 0.22 ± 0.0 0.53 ± 0.1 0.20 ± 0.1 0.00 ± 0.0 3.09 ± 0.7 10.19 ± 1.8 1.99 ± 0.2 1.06 ± 0.2 1.53 ± 0.1 C18:1 n-9c 1.53 ± 0.2 5.22 ± 2.4 1.77 ± 0.1 6.80 ± 0.6 6.87 ± 0.6 9.11 ± 1.3 5.61 ± 0.2 C20:1 n-11 0.16 ± 0.1 0.08 ± 0.0 C20:1 n-7 0.08 ± 0.1 0.30 ± 0.2 0.49 ± 0.1 0.00 ± 0.0 0.40 ± 0.3 0.00 ± 0.0 1.22 ± 0.1 0.00 ± 0.0 0.03 ± 0.0 0.16 ± 0.1 C20:1 n-9 0.58 ± 0.1 0.65 ± 0.1 0.36 ± 0.1 0.65 ± 0.2 0.46 ± 0.1 0.88 ± 0.0 C24:1 n-9 0.31 ± 0.1 0.17 ± 0.0 0.18 ± 0.0 0.30 ± 0.0 0.09 ± 0.1 0.23 ± 0.0 0.11 ± 0.2 0.68 ± 0.2 0.07 ± 0.0 0.41 ± 0.1 0.37 ± 0.1 0.34 ± 0.0 0.27 ± 0.2 0.14 ± 0.1 1.24 ± 0.0 0.00 ± 0.0 1.28 ± 0.1 0.13 ± 0.0 0.16 ± 0.0 FA C18:1 n-7 Abudefduf sexfasciatus Reef slope Reef flat (2) (4) 0.00 ± 0.0 0.19 ± 0.0 0.16 ± 0.0 0.21 ± 0.0 Polyunsaturated C16:2n-4 C16:4n-3 0.51 ± 0.2 0.55 ± 0.2 0.07 ± 0.0 C18:2n-6c 0.72 ± 0.1 1.20 ± 0.2 C18:2n-6t 0.35 ± 0.1 0.39 ± 0.1 0.82 ± 0.0 0.14 ± 0.0 1.11 ± 0.2 0.11 ± 0.0 C18:3 n-3c 0.21 ± 0.0 0.41 ± 0.1 0.35 ± 0.1 0.67 ± 0.4 0.40 ± 0.1 0.16 ± 0.0 0.00 ± 0.0 0.00 ± 0.0 0.00 ± 0.0 C18:3 n-6 0.23 ± 0.1 0.14 ± 0.2 0.00 ± 0.0 C18:3 n-3c 0.28 ± 0.1 0.27 ± 0.0 C18:4 n-3 0.31 ± 0.2 0.32 ± 0.0 1.03 ± 0.3 0.03 ± 0.0 1.58 ± 0.3 0.34 ± 0.3 4.32 ± 0.6 0.15 ± 0.1 2.33 ± 0.1 0.22 ± 0.0 C18:4 n-5 0.03 ± 0.0 0.08 ± 0.0 0.05 ± 0.0 0.07 ± 0.1 0.00 ± 0.0 0.12 ± 0.0 0.21 ± 0.0 0.27 ± 0.0 0.14 ± 0.1 1.29 ± 0.0 0.20 ± 0.0 C20:2 c-11,14 0.32 ± 0.0 0.48 ± 0.1 0.22 ± 0.0 C20:3 isomer 0.20 ± 0.0 0.32 ± 0.0 1.25 ± 0.2 0.95 ± 0.0 C20:3 n-3 0.42 ± 0.1 0.35 ± 0.0 0.56 ± 0.1 0.72 ± 0.1 0.96 ± 0.0 0.24 ± 0.0 C20:4 n-6 5.22 ± 1.4 9.89 ± 1.3 11.23 ± 1.5 9.89 ± 0.3 3.75 ± 0.4 7.20 ± 0.3 0.45 ± 0.1 6.01 ± 0.3 0.04 ± 0.0 0.00 ± 0.0 0.27 ± 0.0 C20:5 n-3* 0.52 ± 0.2 2.57 ± 0.1 0.23 ± 0.1 C22:2 1.40 ± 0.2 3.36 ± 0.7 4.91 ± 0.7 1.25 ± 0.1 8.81 ± 2.3 3.04 ± 1.0 3.05 ± 0.4 0.08 ± 0.0 3.54 ± 0.0 0.08 ± 0.0 C20:4 n-8 Carnivores Deep reef slope (7) Lagoon (4) C22:4 n-6 0.66 ± 0.5 0.14 ± 0.2 Stegastes fasciolatus Reef slope Reef flat (7) (3) 0.12 ± 0.0 0.18 ± 0.1 C22:5 n-3 2.15 ± 0.1 4.24 ± 0.9 4.96 ± 0.5 4.32 ± 0.5 3.09 ± 0.3 4.40 ± 0.2 C22:6 n-3 24.13 ± 5.5 10.93 ± 4.6 14.67 ± 1.5 4.70 ± 1.7 12.68 ± 5.4 19.62 ± 0.7 FA Abudefduf sexfasciatus Reef slope Reef flat (2) (4) 0.93 ± 0.1 1.91 ± 0.1