ESM Fig. 1 Map of Guam indicating study sites where stereo-video surveys of parrotfishes were conducted (black circles). White plus symbols indicate sites within marine reserves. Dark grey represents land, light grey represents reef flat or shallow lagoon, intermediate grey represents outer reef slopes.

ESM Fig. 2 Principal components analysis of life-history traits of twelve parrotfish species. The first principal component explains 80% of the variation among species and therefore summarizes the life history spectrum across species. L50 = length at 50% female maturity; X50 = length at 50% sex change; Lmax = mean length of largest quarter of sampled population (mean maximum length); L1-3 = growth in millimeters from age 1 to 3 years (growth rate proxy); t50 = age at 50% female maturity; Tmax = mean age of oldest quarter of sampled population (mean maximum age). Species positions are denoted by genus and species initials (Calotomus carolinus = Cc, Cetoscarus bicolor = Cb, Chlorurus frontalis = Cf, Chlorurus microrhinos = Cm, Chlorurus spilurus = Cs, Hipposcarus longiceps = Hl, Scarus altipinnis = Sa, Scarus forsteni = Sf, Scarus ghobban = Sg, Scarus psittacus = Sp, Scarus rubroviolaceus = Sr, Scarus schlegeli = Ss).

ESM Fig. 3 Plots of linear regressions performed on phylogenetically independent contrasts of the responses to exploitation (incidence of negative response [a-f] and magnitude of response [g-l]) and life-history traits across twelve parrotfish species. (a,g) length at maturity, (b,h) length at sex change, (c,i) mean maximum length, (d,j) growth rate proxy, (e,k) age at maturity, (f,l) mean maximum age.

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ESM Table 1. Pearson correlation coefficients among species biomass distributions across seventeen sites on Guam.

Cc / Cb / Cf / Cm / Cs / Hl / Sa / Sf / Sg / Sp / Sr / Ss
Calotomus carolinus / - / -0.22 / 0.37 / 0.09 / -0.40 / 0.01 / -0.28 / -0.10 / 0.20 / -0.47 / 0.31 / -0.27
Cetoscarus bicolor / - / 0.11 / -0.03 / 0.12 / 0.35 / 0.31 / 0.31 / -0.17 / 0.42 / -0.02 / 0.25
Chlorurus frontalis / - / 0.14 / -0.20 / 0.64 / -0.03 / 0.21 / -0.02 / -0.20 / 0.75 / -0.33
Chlorurus microrhinos / - / -0.01 / 0.21 / -0.04 / -0.11 / 0.79 / -0.01 / 0.27 / 0.03
Chlorurus spilurus / - / -0.10 / 0.39 / 0.22 / -0.08 / 0.40 / -0.31 / 0.64
Hipposcarus longiceps / - / 0.32 / 0.04 / 0.10 / -0.18 / 0.54 / 0.07
Scarus altipinnis / - / -0.02 / -0.06 / 0.24 / 0.21 / 0.62
Scarus forsteni / - / -0.13 / 0.64 / -0.03 / 0.08
Scarus ghobban / - / -0.04 / 0.13 / 0.14
Scarus psittacus / - / -0.13 / 0.29
Scarus rubroviolaceus / - / -0.21
Scarus schlegeli / -

ESM Table 2. Structure of optimal linear models describing patterns of biomass (natural log-transformed) across sites for each of twelve parrotfish species on Guam. Partial coefficients and significance values for the factor fishing pressure are presented for each species. Values in grey indicate they were derived by fitting a linear model to the residuals of the optimal model, given fishing pressure was not included in the optimal model. coral.rugosity represents the first principal component summarizing variation between highly collinear factors coral cover and rugosity.

species / optimal model structure / r2 / p-value / fishing pressure
coefficient / p-value
Calotomus carolinus / exposure / 0.05 / 0.383 / -0.070 / 0.845
Cetoscarus bicolor / reef flat + fishing pressure / 0.55 / 0.004 / -3.612 / 0.014
Chlorurus frontalis / dist_pass + exposure / 0.53 / 0.005 / -0.056 / 0.964
Chlorurus microrhinos / lagoon + fishing pressure / 0.39 / 0.031 / -2.904 / 0.039
Chlorurus spilurus / coral.rugosity / 0.32 / 0.018 / 0.159 / 0.428
Hipposcarus longiceps / fishing pressure + fringe / 0.43 / 0.019 / -4.164 / 0.010
Scarus altipinnis / exposure * fishing pressure / 0.46 / 0.040 / -5.471 / 0.030
Scarus forsteni / coral.rugosity + fringe / 0.45 / 0.014 / 0.609 / 0.567
Scarus ghobban / coral.rugosity + slope / 0.34 / 0.057 / 0.223 / 0.780
Scarus psittacus / exposure + coral.rugosity / 0.34 / 0.052 / -0.084 / 0.672
Scarus rubroviolaceus / fishing pressure + exposure / 0.61 / 0.001 / -4.054 / 0.011
Scarus schlegeli / fringe + dist_pass / 0.71 / <0.001 / 0.059 / 0.875

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ESM Table 3. Results of linear regression models for mean harvested length from 1990 to 2009 for each of twelve parrotfish species on Guam. The fourth column represents the percentage change in fork length (FL).

a) species / intercept / coefficient / ± % ∆FL / residual df / p-value / r2
Calotomus carolinus / 10.134 / -2.33E-03 / -4 / 105 / 0.587 / 0.003
Cetoscarus bicolor / 52.353 / -2.32E-02 / -32 / 61 / 6.76E-04 / 0.174
Chlorurus frontalis / 17.629 / -6.00E-03 / -4 / 290 / 0.107 / 0.009
Chlorurus microrhinos / 27.511 / -1.09E-02 / -17 / 428 / 5.06E-05 / 0.038
Chlorurus spilurus / 13.165 / -3.88E-03 / -6 / 993 / 0.002 / 0.009
Hipposcarus longiceps / 40.494 / -1.73E-02 / -28 / 605 / 1.55E-10 / 0.066
Scarus altipinnis / 30.350 / -1.23E-02 / -19 / 456 / 1.11E-06 / 0.051
Scarus forsteni / 17.689 / -6.02E-03 / -9 / 181 / 0.040 / 0.023
Scarus ghobban / -0.982 / 3.28E-03 / +1 / 151 / 0.545 / 0.002
Scarus psittacus / 20.315 / -7.47E-03 / -12 / 541 / 4.74E-05 / 0.030
Scarus rubroviolaceus / 43.710 / -1.89E-02 / -25 / 209 / 8.99E-07 / 0.109
Scarus schlegeli / 24.770 / -9.65E-03 / -16 / 889 / 3.93E-06 / 0.024

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