Towards an Everyday Nature Index for biodiversity in urban streets

Vegetation in contemporary urban streetscapes is generally limited to street trees and grassy verges, with limited understorey, species diversity, or habitat value. The increasing recognition that human-nature interactions offer substantial benefits to urban residents demands new ways of planning and designing urban streetscapes. To drive this change, new measures of success are required that quantify the fundamental resources needed to support more complex ecosystems. This requires a significant step beyond existing canopy-focused ‘urban forestry’ metrics. Here we propose a metric that can quantify streetscape support for biodiversity as a composite index, incorporating measures of vegetation structure, diversity, nativeness and connectivity. We conduct a trial scoring of these components in five diverse residential streetscapes, enabling calculation of an ‘everyday nature’ index for each street. Even as a prototype, the metric’s results encourage attention to important fundamentals of urban biodiversity, in a way that sets it apart from existing urban greening metrics. Future development is required for the metric to be operationalised, with our trial of the method identifying a series of frontiers which will require a significant program of research. Once validated the metric should be able to be used in 'everyday nature’ benchmarking of streets and neighbourhoods. Our vision is that this index, once fully developed, could be used in the same way as existing popular ‘liveability’ metrics, informing resident’s choices and driving city-wide investment in nature.