Fig. 4

Exploratory analysis for interaction terms that were included in the top model set (top 2 AIC_c scores; Table 2); the response variable and parameter of interest were regressed separately for each year. a scaled mass index: δ¹³C * year (2011: r² = 0.17, p = 0.03; 2012: r² = 0.03, p = 0.37), b scaled mass index: δ¹⁵N * year (2011: r² = 0.04, p = 0.32; 2012: r² = 0.009, p = 0.6); b BUTY: δ¹⁵N * year (2011: t = 1.83, p = 0.08; 2012: t = −1.34, p = 0.19); c TRIG: δ¹³C * year (2011: t = −1.7, p = 0.1; 2012: t = 0.34, p = 0.74). Time at capture and scaled mass index were included as covariates in c BUTY and d TRIG models (see “Methods” section), plots show the raw data