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Dealing with the erosion of terrestrial biodiversity has become of key importance in order to ensure ecosystems sustainability. Agricultural and forestry activities are one major anthropogenic driver of this decline. The underlying land-use changes result in the alteration of species habitats. In this context reconciling economic and ecological objectives of agricultural policies remains an ongoing challenge. In that respect, this paper presents the bioeconomic impacts of contrasted agricultural public policy scenarios. We developped a bio-economic model coupling an ecological model of bird dynamics with a micro-economic model of land management estimated with French data. We assessed the performances of the scenarios based on 5 ecological indicators accounting for various structural and functionnal characteristics while economic performances refer to land-use incomes. First our study confirms the potential long-term synergies between several ecological and economic objectives in grassland-based policies. Second we points out the non-trivial effect of agroforestry policies on agricultural biodiversity: despite a positive overall impact on the biodiversity population size, it implies important structural changes within the community. The choice between grassland-based policies such as in Agri-Environmental Schemes and agroforestry policies will thus depend on the ecological stakeholders' preferences.