Data from: Responses of insect pollinators to habitat fragmentation: A global meta-analysis

Insect pollinators are declining globally, with habitat fragmentation
recognized as an important driver. While these declines have garnered
widespread public and policy attention, current evidence
remains largely limited to certain taxa, geographic regions, and
ecosystems, thereby resulting in diverse outcomes. Here, we aimed to
present a global meta-analysis using a dataset comprising 80 studies
across 28 countries on all continents, excluding
Antarctica. We used Pearson’s correlation coefficient (r) as an
effect size to measure the association between habitat fragmentation
and the abundance and species richness of wild bees,
butterflies, and wasps. Subsequently, we performed
categorical meta-analyses that fragmentation indices, climates,
and taxonomic groups as moderators to investigate the dependency
of habitat fragmentation effects on these factors. Increasing habitat
fragmentation was significantly associated with
reductions in both the abundance (r = -0.26, CI: -0.39, -0.12)
and species richness (r = -0.46, CI: -0.55, -0.35) of insect
pollinators. The magnitude of these associations varied
depending on the evaluated fragmentation index. Specifically, pollinator
abundance (r = -0.43, 95%CI: -0.56, -0.29) and species
richness (r = -0.62, 95%CI: -0.71, -0.52) significantly decreased with
reduced habitat area. Synthesis and Applications. Our results
show that insect pollinators have declined globally due
to habitat fragmentation. Reduced habitat area and increased edge density
were the main drivers of pollinator decline. The
findings indicate that preserving large habitats can support more
insect pollinators. This implies that policies
must target the landscape scale to mitigate the negative
effects of habitat fragmentation.