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Habitat degradation and fragmentation are two of the main drivers for biodiversity loss. To mitigate the negative impact of fragmentation in forests, conservation targets are increasingly addressing connectivity to facilitate the independent movement of species between habitat fragments to ensure genetic diversity and adaptation to climate change. In this article, we present a novel approach to identifying and prioritizing stepping stones for preserving connectivity based on national and regional biodiversity data for Austrian forest ecosystems. Our study identified forest areas where conservation measures should be taken to ensure future habitat connectivity by combining four indicator values with different requirements of a stepping stone habitat into a prioritization value. The four compounded indicators are: (i) the Protect Value, which includes distances to patches of protected areas with restricted management for the undisturbed development of retention areas, (ii) the Connect Value, which combines datasets of designated habitat corridors and connectivity areas in Austria based on landscape models and expert validation, (iii) the Species Value identifying species‐rich areas, and (iv) the Habitat Value identifying biotopes of high ecological value, key biodiversity areas, and sites of favorable protection status. Nonparametric tests revealed significant differences in prioritization value among the ecoregions of Austria and therefore encourage the consideration of stepping stone prioritization at local and regional context. Building upon the insights from this case study on Austrian forest ecosystems, we developed a robust framework derived from our methodology. This framework is designed to facilitate future implementations in diverse study regions, accounting for factors beyond connectivity crucial for identifying high value stepping stone habitats. We encourage adaptation of this framework to local data availability, species requirements, and local conditions. The compiled framework provides decision support for managers and conservationists for prioritizing areas to conserve and improve connectivity of forest habitats. However, it does not substitute on‐the‐ground field assessments of habitat quality and measures of functional connectivity. [ABSTRACT FROM AUTHOR]

• We tested a rapid assessment for saproxylic insects based on feeding galleries and boreholes. • 3641 standing and lying dead objects were examined in 1,444 NFI plots for insect traces. • We found 2,770 insect traces of the orders Coleoptera (n = 2,624), Hymenoptera (n = 143) and Lepidoptera (n = 3) • All insect abundances increased on trees taller than 18 m and above a living stand volume of 41 m3ha−1. • We recommend a tree species-specific dead wood management already considering living wood. Knowledge of habitat requirements of saproxylic insects and their response to habitat changes is critical for assessing the ecological impacts of forest management. Several studies have demonstrated a positive relationship of tree-species richness, deadwood volume, or structural diversity with saproxylic species diversity, while the relationship with the abundance of potential pest species have often been negative. A better understanding of which factors drive saproxylic insects' occurrence is therefore essential for deriving urgently needed thresholds for key habitat conditions. We tested a rapid assessment method applicable at large scale based on recorded feeding galleries and boreholes assessed during the Austrian National Forest Inventory to investigate the drivers and habitat thresholds of different saproxylic insect families; i.e. Buprestidae, Cerambycidae, Curculionidae, Siricidae, at multiple spatial scales; i.e. at the object, forest stand and landscape level. We modelled the relative abundance of all insects and these families considering nineteen explanatory variables using ordinal logistic regression models. Key habitat characteristics were identified using recursive partitioning. Our results revealed complex interactions among influencing factors at different spatial scales. We showed that deadwood volume was of surprisingly little importance. Instead, individual tree characteristics were of major importance, demonstrating the value of resource quality and variability. The abundance of all saproxylic insect families increased with advancing decomposition, on trees taller than 18 m, and above a living stand volume of 41 m3ha−1. Aiming to guide forest management, not only forest type-specific, but tree species-specific deadwood management is needed, taking into account site-specific conditions, including temperature and precipitation. For assessing temporal trends in insect colonization and habitat dynamics as well as the effects of forest management, we propose a continuous monitoring of insect traces, including living but weakened trees. This will allow for further thresholds that are urgently needed for maintaining biological diversity in forest ecosystems in the face of climate change. [ABSTRACT FROM AUTHOR]

• Our review linked 44 biodiversity indicators with 32 forest management indicators. • Arthropods, birds, and plants are the most frequently used biodiversity indicators. • 14 Forest management measures were defined to influence biodiversity indicators. • We identified 17 umbrella species, but clear thresholds for forest management are still missing. • Measures related to deadwood, stand structure and management intensity affect biodiversity most. The accelerating global rate of species extinctions and the inevitable human impacts on biodiversity have increased the need to conserve, restore and use ecosystems sustainably. Indicators for biodiversity are the most frequently used tool to monitor the status of biodiversity, changes to biodiversity, and the effects of management actions. In this study, we aim to assess the magnitude of studies on indicators for biodiversity (IB) in European forest ecosystems, establish and analyze the link between IB and silvicultural management measures (MM), and define indicators for management (IM), that aim to support biodiversity at the stand and landscape level. We performed a systematic literature review and analyzed data from 162 studies. We identified 9 IB groups, corresponding to 32 IB and linked them to 7 IM groups corresponding to 44 IM. Arthropods, birds, and plants are the most frequently used IB in European managed forests. We found IB with clear links to specific IM, such as saproxylic species and Collembola (collembolans) with deadwood, bird families (Passeriformes, Piciformes, Accipitriformes) with links to microhabitats, and ground-dwelling species with links to regeneration. We identified 17 species as proposed umbrella species based on the studies examined. This review shows that high structural diversity is associated with an increase in diversity, especially with regard to vascular plants, birds and ground-dwelling species. The adaptation of forest management for biodiversity requires regular active monitoring of IM to assess the temporal and spatial changes and of IB to assess the effectiveness of measures. [ABSTRACT FROM AUTHOR]