Appendix 1: Effects of mean breeding season temperatures and smoothed annual mean temperatures, on inter-annual variation in body mass. Shown are n, the t- and p-values and the slopes (B) of the temperature variable as well as the adjusted R² of linear regressions for each species. Separate regressions were run for each of the two temperature variables. In bold are the names of the species for which at least one of the temperature effects was statistically significant, and the AIC scores for the best-supported model (lowest AIC value) of temperature effects for these species.

Species

/ n / t / p / adj R² / B / AIC / ∆AIC
Dunnock / Breeding season temp. / 557 / -1.873 / 0.062 / 0.298 / -0.083 / 1780.54 / 3.37
Smoothed annual temp. / 557 / -0.397 / 0.691 / 0.294 / -0.048 / 1783.91
Robin / Breeding season temp. / 1571 / 0.020 / 0.984 / 0.241 / <0.001 / 4249.51 / 0.31
Smoothed annual temp. / 1571 / -0.554 / 0.580 / 0.241 / -0.028 / 4249.20
Song thrush / Breeding season temp. / 228 / 0.370 / 0.712 / 0.262 / 0.090 / 1305.92 / 0.17
Smoothed annual temp. / 228 / -0.554 / 0.580 / 0.263 / -0.323 / 1305.75
Blackbird / Breeding season temp. / 1167 / -0.997 / 0.319 / 0.299 / -0.140 / 7219.98 / 3.59
Smoothed annual temp. / 1167 / -2.139 / 0.033 / 0.301 / -0.727 / 7216.39
Garden warbler / Breeding season temp. / 325 / 1.848 / 0.066 / 0.105 / 0.090 / 946.71 / 2.33
Smoothed annual temp / 325 / 1.057 / 0.292 / 0.099 / 0.127 / 949.04
Blackcap / Breeding season temp. / 4440 / 5.900 / <0.001 / 0.335 / 0.075 / 12487.44 / 32.63
Smoothed annual temp. / 4440 / 1.441 / 0.150 / 0.330 / 0.046 / 12520.07
Reed warbler / Breeding season temp. / 1667 / -2.446 / 0.015 / 0.092 / -0.037 / 3388.56 / 7.91
Smoothed annual temp. / 1667 / -3.730 / <0.001 / 0.092 / -0.133 / 3380.65
Willow warbler / Breeding season temp. / 1451 / -1.668 / 0.096 / 0.183 / -0.028 / 2989.29 / 7.01
Smoothed annual temp. / 1451 / -3.130 / 0.002 / 0.187 / -0.139 / 2982.28
Chiffchaff / Breeding season temp. / 8938 / -4.494 / <0.001 / 0.220 / -0.023 / 14774.01 / 6.73
Smoothed annual temp. / 8938 / -5.190 / <0.001 / 0.221 / -0.064 / 14767.28
Great tit / Breeding season temp. / 877 / 0.316 / 0.752 / 0.209 / -0.009 / 2444.71 / 1.36
Smoothed annual temp. / 877 / -1.205 / 0.228 / 0.211 / -0.095 / 2443.35
Blue tit / Breeding season temp. / 2202 / -3.716 / <0.001 / 0.183 / -0.041 / 4033.47 / 8.51
Smoothed annual temp. / 2202 / -4.729 / <0.001 / 0.186 / -0.121 / 4024.96
Reed bunting / Breeding season temp. / 4037 / 1.062 / 0.288 / 0.113 / 0.019 / 13949.12 / 0.92
Smoothed annual temp. / 4037 / 0.454 / 0.650 / 0.113 / 0.020 / 13950.04

Appendix 2: Effects of annual mean breeding season temperatures and smoothed annual mean temperatures on inter-annual variation in feather length. Shown are n, the t- and p-values and the slopes (B) of the temperature variable as well as the adjusted R² of linear regressions for each species. Separate regressions were run for each of the two temperature variables. In bold are the names of the species for which at least one of the temperature effects was statistically significant, and the AIC scores for the best-supported model (lowest AIC value) of temperature effects for these species.

Species / n / t / p / adj R² / B / AIC / ∆AIC
Dunnock / Breeding season temp. / 531 / 2.452 / 0.118 / 0.003 / -0.093 / 1980.77 / 2.45
Smoothed annual temp. / 531 / <0.001 / 0.990 / <0.001 / 0.002 / 1983.22
Robin / Breeding season temp. / 1535 / 0.287 / 0.593 / <0.001 / 0.020 / 5994.91 / 7.48
Smoothed annual temp. / 1535 / 7.778 / 0.005 / 0.004 / 0.255 / 5987.43
Song thrush / Breeding season temp. / 266 / 0.069 / 0.793 / <0.001 / 0.028 / 1145.70 / 0.06
Smoothed annual temp. / 266 / 0.007 / 0.933 / <0.001 / 0.023 / 1145.76
Blackbird / Breeding season temp. / 1131 / 3.871 / 0.049 / 0.003 / 0.170 / 5895.59 / 5.73
Smoothed annual temp. / 1131 / 9.628 / 0.002 / 0.008 / 0.659 / 5889.86
Garden warbler / Breeding season temp. / 307 / 0.011 / 0.916 / <0.001 / 0.009 / 1188.69 / 0.91
Smoothed annual temp. / 307 / 0.914 / 0.340 / <0.001 / 0.191 / 1187.78
Blackcap / Breeding season temp. / 4390 / 44.694 / <0.001 / 0.010 / -0.134 / 16383.87 / 11.79
Smoothed annual temp. / 4390 / 32.809 / <0.001 / 0.007 / -0.285 / 16395.66
Reed warbler / Breeding season temp. / 1527 / 28.312 / <0.001 / 0.018 / -0.188 / 5645.12 / 20.13
Smoothed annual temp. / 1527 / 7.973 / 0.005 / 0.005 / -0.239 / 5665.25
Willow warbler / Breeding season temp. / 1406 / 9.342 / 0.002 / 0.006 / -0.184 / 6473.11 / 0
Smoothed annual temp. / 1406 / 9.335 / 0.002 / 0.006 / -0.487 / 6473.11
Chiffchaff / Breeding season temp. / 8717 / 9.904 / 0.002 / 0.001 / -0.068 / 39775.34 / 27.4
Smoothed annual temp. / 8717 / 37.368 / <0.001 / 0.004 / -0.320 / 39747.94
Great tit / Breeding season temp. / 856 / 2.782 / 0.096 / 0.002 / 0.086 / 3527.00 / 2.73
Smoothed annual temp. / 856 / 0.056 / 0.812 / <0.001 / -0.035 / 3529.73
Blue tit / Breeding season temp. / 2149 / 6.988 / 0.008 / 0.003 / -0.081 / 8458.52 / 0.06
Smoothed annual temp. / 2149 / 6.918 / 0.009 / 0.003 / -0.184 / 8458.58
Reed bunting / Breeding season temp. / 3756 / 0.005 / 0.945 / <0.001 / -0.003 / 17754.82 / 0.08
Smoothed annual temp. / 3756 / 0.086 / 0.770 / <0.001 / -0.024 / 17754.74

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