Avian biodiversity: impacts of phytosanitary practices and landscape in South-Eastern French apple orchards
Abstract: In French apple orchards, the predominant conventional management strategy has resulted insecticide resistance in major pests like codling moth and an increased frequency of environmentally harmful insecticide applications. Organic agriculture as well as IPM represent alternatives to this situation.Impacts on the avifauna of three different management strategies (organic, conventional and integrated) were studied during three years in 15 commercial apple orchards. These orchards were situated around Avignon and had similar contexts in terms of local and landscape features.Our results show that the avifauna differ significantly among the three management strategies with abundances of 46, 30.3 and 7.6 individuals/ha for the organic, integrated and conventional orchards respectively; species richness of 18.1, 14 and 7.6 breeding species/ha respectively and Shannon diversity indexes of 3.8, 3.3 and 2.6 respectively. The functional structure of bird communities is also affected, with a lesser proportion of insectivores in conventional orchards than in other orchards. Phytosanitary and environmental factors taken together explain 52% of the variability of the composition of bird communities. Phytosanitary treatments and local environment of the orchards had a similar explanatory power of 11% while environment at the landscape scale explained approximately 19% of the variability.We have demonstrated an important impact of phytosanitary practices on all parameters used to describe bird communities. These results highlight the influence of fruit production on avian biodiversity and its consequences in terms of protection of species of agronomical or patrimonial interest.