COS 92-3 - From yards to cities: scaling up management for biodiversity conservation

Abstract: Urban landscapes constitute a complex mosaic of vegetation or green spaces that serve as habitat patches. Although relatively small, fragmented, and often isolated, these habitat patches support many species. The quality, composition, and size of habitat patches vary tremendously, depending on ecological and social factors, which drive urban biodiversity patterns at nested spatial scales. Urban habitats are increasingly managed and being restored for biodiversity conservation, but management actions seldom consider the cross-scale, socioecological interactions, and can create scale mismatches, whereby management does not match the scale of ecological processes, leading to a reduction in ecological function and ecosystem services. Here, we explore how ecological and social factors that operate at multiple spatiotemporal scales influence urban biodiversity patterns and the composition and configuration of habitat patches. We highlight how scaling can inform urban planning, management, and the conservation of urban biodiversity. We use residential yards as a focal point, given that their spatial coverage and connection throughout the urban matrix represents a significant opportunity for biodiversity conservation.

An individual yard is intricately linked to a network of yards and scales up to the neighborhood, city, and region. The potential to support biodiversity and management actions operates within and across these spatial scales. At the individual yard scale, the selection of native cultivars, reduced mowing frequency, or keeping cats indoors can increase genetic diversity and vegetation structural complexity, and support food webs. At the neighborhood scale, variation in socioeconomic status, legacies of previous residents, policies and social norms determine the composition and configuration of habitat in groups of adjacent yards. At the city scale, promoting native plants, protecting remnant habitat patches, and clustering of residential habitats with other urban green spaces reflect urban planning and green infrastructure strategies. These planning and management actions can support native biodiversity and increase ecological connectivity across the city, while providing opportunities to engage with residents at each scale. The functional connectivity of individual yards depends upon the ecological features and management practices across multiple yards that facilitates species movement throughout the urban matrix. Counteracting scale mismatches requires ecologists and planners to take on a holistic multi-scale approach to urban biodiversity management, policy, and planning that coordinates these three arms of decision-making during goal setting, implementation, and monitoring.