Small patches, big differences: How landscape structure shapes Scolytinae communities in pine plantations

Landscape structure shapes herbivorous insect distribution and abundance, yet its effects on scolytine beetles in exotic pine plantations remain poorly understood. We analysed patch‐scale (patch area, Euclidean nearest‐neighbour distance) and landscape‐scale (total core area of pine, mean nearest‐neighbour distance) metrics on the abundance of nine Scolytinae species in fragmented pine plantations of central Córdoba, Argentina.

We used generalised linear mixed models (GLMMs) with a negative binomial distribution and multimodel inference (AICc‐based model averaging) to assess the effects of patch‐scale (area, isolation) and landscape‐scale (total pine cover, mean inter‐patch distance) metrics on the abundance of each species.

The analyses revealed contrasting responses structured by ecological guild. The pine‐specialist bark beetle Hylurgus ligniperda showed higher abundance in landscapes with greater connectivity (shorter mean inter‐patch distances), reflecting its long‐distance dispersal capacity. In contrast, Orthotomicus erosus showed non‐significant trends towards higher abundance in smaller patches within landscapes of extensive pine cover, suggesting a possible edge preference coupled with landscape‐scale host availability. The opportunistic ambrosia beetle Xyleborinus saxesenii exhibited strong negative associations with both patch area and nearest‐neighbour distance, indicating higher abundance in smaller, well‐connected patches, a pattern linked to its cooperative breeding behaviour. Native species showed no landscape associations, likely reflecting their polyphagous habits. Six species represented new records for Córdoba: Amasa parviseta , Cyrtogenius luteus , Xyleborinus saxesenii , Xyleborus bispinatus , Scolytus multistriatus and Xyleborus ferrugineus .

Our results demonstrate that landscape configuration differentially affects bark and ambrosia beetles according to their ecological traits, with implications for pest management in fragmented pine plantations.