Selective logging weakly influences species co-occurrence in a community of tropical understorey birds.

Abstract

Selective logging is a major driver of tropical land-use change, causing reductions in forest specialist species with concurrent increases in edge-tolerant species. A key question is understanding how selective logging impacts co-occurrence and assembly mechanisms in vertebrate communities as forests recover post-logging. Using a 10-year, repeat-sample study of understorey bird species in Borneo, we compare the structure of species co-occurrences over time between old-growth unlogged and logged forests, investigating the roles of functional traits and local abundance in driving co-occurrence patterns. Co-occurrence patterns were resilient to selective logging over time, although patterns were not consistent across all species in both forest types. Species with more specialised diets showed a significant tendency towards low fidelity, while species that engage in aerial foraging, soaring and gliding exhibited a significant tendency to have low values of fidelity in both types of forest. Changes in co-occurrence patterns were also significantly influenced by changes in local abundance. Our results indicate that niche segregation and environmental filtering operate to shape the assemblage of the avian community in both forest types, but co-occurrence was resilient to selective logging over time. Our results also underscore the role of some species in regulating avian assemblages and the long-term conservation value of logged tropical forests.