Biodiversity-Friendly Management in Olive Groves Supports Pollinator Conservation in a Mediterranean Terraced Landscape.

Abstract

While olive trees are primarily wind-pollinated, biodiversity-friendly management of the groves can contribute to the conservation of pollinating insects in olive agroecosystems. Previous research demonstrated that semi-natural habitats, such as herbaceous linear elements and woody areas, support the community of pollinators in agroecosystems. Less is known about the contribution of low-input olive groves with a permanent ground cover on terraced landscapes. This study investigated the relationship between pollinator communities and semi-natural habitats, including spontaneous vegetation, in a traditional terraced Mediterranean olive grove agroecosystem. The research employed pan traps to monitor wild bees and observation walks to assess the butterfly community across three different habitat types in spring, summer, and autumn during two growing seasons. Floral resources in the habitats were assessed during each sampling time. Analysis showed that herbaceous habitats support a higher abundance of wild bees than woody areas, while olive groves do not differ significantly from either habitat type, despite exhibiting the highest floral abundance. This suggests that habitat structure, rather than floral availability alone, plays a role in maintaining the wild bee community. For butterflies, results demonstrate that the overall abundance does not differ between habitats, while the species composition does. The study emphasizes the importance of preserving diverse habitats, and in particular low-input olive groves, within agricultural landscapes to support a wide range of pollinator species.