Bird conservation and the land sharing‐sparing continuum in farmland‐dominated landscapes of lowland England

Abstract

Empirical evidence from many regions suggests that most species would be least negatively affected if human food demand were met through high‐yield agricultural production and conservation of nonfarm ecosystems (land sparing), rather than through wildlife‐friendly farming over a larger area (land sharing). However, repeated glaciation and a long history of agriculture may lead to different results in regions such as western Europe. We compared the consequences of land sparing and land sharing on breeding bird species in 2 lowland regions of England, The Fens, with 101 species, and Salisbury Plain, with 83. We derived density–yield responses for each species and then estimated regional population size under regional food production strategies, including land sharing and land sparing, a range of intermediate strategies, and a novel mixed strategy. In both regions, more species achieved maximum regional population size under land sparing than land sharing. In The Fens, the majority of birds were loser species (estimated to have smaller populations under all food production strategies than in the preagricultural baseline scenario), whereas in Salisbury Plain the majority were winners (smaller populations in the preagricultural baseline scenario). Loser species overwhelmingly achieved maximum regional population size under land sparing, whereas winner species achieved maximum regional population size under either land sharing or an intermediate strategy, highlighting the importance of defining which groups of species are the target of conservation. A novel 3‐compartment strategy (combining high‐yield farming, natural habitat, and low‐yield farming) often performed better than either land sharing or land sparing. Our results support intermediate or 3‐compartment land‐sparing strategies to maximize bird populations across lowland agricultural landscapes. To deliver conservation outcomes, any shift toward land sparing must, however, ensure yield increases are sustainable in the long term, do not entail increased negative effects on surrounding areas, and are linked to allocation of land for nature.

Roads as a contributor to landscape-scale variation in bird communities

“…Therefore, by the beginning of this period, sensitive species may have already adjusted to the presence of the road network. Shifts in species assemblages in areas of high human disturbance have been identified in both urban 4,5 and agricultural 57 environments, and in response to climate change 5,6 . Rather than declines of so-called 'loser' species happening in isolation, simultaneous replacement of those species by expanding 'winner' species occurs 3,7,8,58 .…”

Drought exacerbates negative consequences of high‐intensity cattle grazing in a semiarid grassland

“…In contrast, land-sparing areas have high-density built areas (e.g., multi-story buildings) with set-aside, large-sized, continuous green areas (Lin and Fuller 2013). Although this dichotomy is somewhat arbitrary, as it emphasizes the endpoints of a continuum rather than its gradual nature (Kremen 2015, Finch et al 2019, understanding how these two land-development approaches affect urban ecosystems and biodiversity is of key importance for city planning.…”

Land‐sharing vs. land‐sparing urban development modulate predator–prey interactions in Europe

“…Although this dichotomy is somewhat arbitrary, as it emphasizes the endpoints of a continuum rather than its gradual nature (Kremen , Finch et al. ), understanding how these two land‐development approaches affect urban ecosystems and biodiversity is of key importance for city planning.…”