Construction of the food webs
We analyzed the stomach contents of all fish species (see Appendix:stomach contents ) and jointly with literature (e.g., Lopez- Rodriguez et al. 2019), we created a general meta-web, that compiles all species interactions (Fig. S3 and Table S1). From this general meta-web, we created food webs for each site and sampling period, totaling 179 food webs. We then lumped fish communities into four feeding guilds: top-carnivores, mesocarnivores, omnivores, and detritivores (Table S1). Top-carnivores are those which exclusively feed on other fish species. Mesocarnivores were assigned to individuals that preferentially feed on invertebrates. Omnivores were designed for individuals that feed on at least two different resources: invertebrate–plant/algae, invertebrate–detritus. Detritivores were intended as individuals that feed exclusively on detritus.