Abstract Although agricultural expansion is one of the main causes of tropical deforestation, some agroecosystems, such as shaded cocoa agroforests, can minimize the effects of habitat loss and contribute to biodiversity conservation. Nonetheless, the effects of habitat modification at the regional and landscape scales on insect diversity inhabiting agricultural landscapes are still poorly understood, especially for Ichneumonidae wasps. Here, we investigated how the diversity of Ichneumonidae subfamilies varies between agricultural and native environments (i.e., cocoa agroforestry and Atlantic Forest remnants), and evaluated the effect of land cover context (highly forested, moderately forested, and severely deforested regions) and landscape forest cover on wasp diversity. For this, we deployed three Malaise traps for three consecutive days to collect wasps within 30 pairwise cocoa-forest sites distributed in three regions of southern Bahia, Brazil. We then separated and identified only Ichneumonidae wasps, therefore obtaining the number of subfamilies (subfamily richness) and the number of individuals (abundance) per site. We constructed Generalized Linear Mixed Models, using “landscape” as a random factor, to investigate how different environments (agroforestry or forest), regional context, and landscape forest cover affect the abundance and subfamily richness of Ichneumonidae, employing a parsimonious model selection approach. In total, we collected 421 individuals from 19 subfamilies. All predictors were included in the best models explaining patterns of both abundance and richness, with region appearing as the most important predictor in both cases, followed by forest cover. Implications for insect conservation Our results highlight the potential of shaded cocoa agroforest for maintaining high diversity of Ichneumonidae subfamilies, especially in those located in moderately and highly forested regions and surrounded by great amount of forest cover. Thus, we emphasize the importance of ensuring high amount of native areas in agricultural landscapes, especially through forest restoration strategies.
Rocha et al. (Fri,) studied this question.