Land sharing or land sparing? Implications for farmland birds of conservation concern in France

Artikel i vetenskaplig tidskrift, 2026

Purpose: Farmland bird populations have experienced widespread declines across Europe, raising urgent questions about how agricultural landscapes should be structured to reconcile biodiversity conservation and food production. Land sparing and land sharing represent two contrasting strategies, yet empirical evidence remains mixed.
Objectives: We aim to quantify responses of bird communities along a land sharing–sparing gradient and identify which landscape management strategies best support different ecological groups.
Methods: Using the French Breeding Bird Survey, we analyzed 810 locations monitored between 2001–2024. A land sharing–sparing gradient was quantified using forest area, agricultural heterogeneity, and landscape diversity indices. Bird counts were modeled with negative binomial spatio-temporal Bayesian models (INLA), incorporating climate, spatial random fields, and temporal autocorrelation. Results: Forest specialists responded positively to greater forest area, supporting land sparing. Generalists benefited from higher agricultural heterogeneity, consistent with land sharing. Unexpectedly, farmland specialists did not benefit from increased heterogeneity, and conservation-priority farmland species showed negative associations with natural elements.
Conclusion: No single land-use strategy maximizes abundance across all bird groups. Land sparing favors forest specialists and conservation-priority species, while land sharing benefits generalists. Context-dependent landscape planning and customized agricultural practices are essential.