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Climate change risk assessments are essential for the successful conservation and management of species under future climates. However, many management plans fail to include such assessments when evaluating threats to species or ecological communities. Species distribution models (SDMs) are versatile tools that can estimate species exposure to shifts in climate, but they lack information on the response capacity of species to climate change. Functional traits can be used in conjunction with SDMs to understand aspects of species biology that would suggest sensitivity to climate change. We illustrate how exposure to climate change and sensitivity of species based on their traits can be combined to generate predictions of climate change risk in four species listed as threatened (under state and federal legislation) and four unlisted plant species from the endemic Australian genus Persoonia (Proteaceae). We develop distribution models for each species using two emissions scenarios and assess four traits and two range metrics that are recognized as limiting factors in four potential climate change responses (reproduction, movement capability, habitat specialization, and spatial coverage) to assess the sensitivity of these eight species to climate change. Listed and unlisted species varied in niche breadth, environmental envelopes, and the percent contribution of variables to the model building process. Our models project a significant decline in habitat suitability under future climates at current occurrence locations for all species, and a 32–95% reduction in the total area (km2) of suitable habitat for all species by 2060, with significantly greater decline under the higher emissions scenario. Seven out of the eight species assessed ranked high for overall climate sensitivity therefore listing status may be a poor indicator of climate change risk to plant species. This has important implications for the continued focus on threatened taxa in conservation planning, particularly for hyper-diverse groups like plants ...

Societal Impact Statement: Globally, cities are planning for resilience through urban greening initiatives as governments understand the importance of urban forests in improving quality of life and mitigating climate change. However, the persistence of urban forests and the ecosystem benefits they provide are threatened by climate change, and systematic assessments of causes of tree dieback and mortality in urban environments are rare. Long-term monitoring studies and adaptive management are needed to identify and prevent climate change-driven failures and mortality. Research and monitoring when coupled with systematic forecasting will enable governments to incorporate climate change resilience into urban forestry planning. Future scenarios in which urban forests are resilient or in decline will depend on the management and planning actions we make today. Summary: The management of urban forests is a key element of resilience planning in cities across the globe. Urban forests provide ecosystem services as well as other nature-based solutions to 4.2 billion people living in cities. However, to continue to do so effectively, urban forests need to be able to thrive in an increasingly changing climate. Trees in cities are vulnerable to extreme heat and drought events, which are predicted to increase in frequency and severity under climate change. Knowledge of species' vulnerability to climate change, therefore, is crucial to ensure provision of desired ecosystem benefits, improve species selection, maintain tree growth and reduce tree mortality, dieback and stress in urban forests. Yet, systematic assessments of causes of tree dieback and mortality in urban environments are rare. We reviewed the state of knowledge of tree mortality in urban forests globally, finding very few frameworks that enable detection of climate change impacts on urban forests and no long-term studies assessing climate change as a direct driver of urban tree dieback and mortality. The effects of climate change on urban forests remain poorly understood and quantified, constraining the ability of governments to incorporate climate change resilience into urban forestry planning.