Habitat complexity drives food web structure along a dynamic mangrove coast

Structurally complex habitats, such as mangrove forests, allow for rich assemblages of species that benefit from the provided space, volume and substrate. Changes in habitat complexity can affect species abundance, diversity and resilience. In this study, we explored the effects of habitat complexity on food web networks in four developmental stages of mangrove forests with differing structural complexities: climax > degrading > colonizing > bare, by analyzing food web structure, stable isotopes and habitat complexity. We found that food webs became gradually more biodiverse (species richness: +119 %), complex (link density: +39 %), and robust (connectance: −35 %) in climax versus bare stages with increasing complexity of the mangrove forest (i.e., number of trees, leaf cover, and pneumatophore densities). This study shows that habitat complexity drives food web network structure in dynamic mangrove forests. We recommend restoration practitioners to use this food web network approach to quantify habitat restoration successes complementary to traditional biodiversity metrics.