Treesearch

Rapid changes in landscape structure can disrupt the ecology and life history of species of conservation concern. Shifting climate, land-use, and disturbance regimes are generating novel landscape patterns, and it is unclear how these novel conditions may affect imperiled species. In the Sierra Nevada of California, USA, extensive drought-induced tree mortality has rapidly altered forest structure and local microclimates, with potential implications for forest-dependent species. We evaluated the effects of shifting land cover, forest structure, and abiotic conditions on the space-use of...

Density management diagrams (DMDs) are a fundamental forest management tool. However, these tools were primarily developed for even-aged stands and may not incorporate important site effects. Accommodating different stocking constraints during stand development across broad ranges of site effects could help tailor reforestation and thinning prescriptions to local conditions. For that purpose, this report introduces a set of site-sensitive DMDs for managing both even- and uneven-aged California mixed-conifer stands. By consulting maps of aridity and nitrogen deposition summarized by...

Mechanistic habitat assessment models have long been used for stream fish, especially drift-feeding salmonids. Most of these models assess habitat value as the rate of net energy intake (growth) obtained by a fish feeding in a habitat unit. However, the fitness value of habitat and the willingness of fish to occupy it also depend on predation risk: habitat is not valuable if it offers high growth but also high risk. Methods for modeling how predation risk varies with characteristics of habitat and fish are much less developed than those for modeling net energy intake. We present approaches...

Climate change is reducing the extent of cold aquatic habitats and their unique biodiversity in mountain areas. However, a variety of cold rocky landforms (CRLs) are thermally buffered and feed cold springs (<2 °C) that may represent climate refugia for cold-adapted organisms. These landforms, hitherto overlooked by freshwater research, include rock glaciers, debris-covered glaciers, talus slopes, protalus ramparts, and young moraines. Here, we investigated the warm-season water temperature of 228 springs from clean (ice) glaciers, CRLs, and reference slopes (not sourced by any of these...

The stability of seasonally dry Western mixed-conifer forests is threatened by the history of fire suppression, logging, and now increasing climate-driven aridity. Durable aboveground carbon storage in living trees–a key ecosystem service of these fire-adapted forests–is at risk due to the disruption of natural fire cycles. Restoring the relationship between fire and forest structure is essential for long-term resilience. Fuel and density reduction treatments can help reestablish this balance by reducing fire severity and enhancing forest function. We evaluated the effectiveness of 216...

Socio-ecological resilience recognizes that humans and nature are inextricably connected, and humans play an increasingly central and active role in determining the fate of ecosystem resilience. For decades, managers and scientists have sought effective approaches for managing forest composition, structure, and processes to improve resilience properties. Management actions that encompass large landscapes tend to engage a broad spectrum of stakeholders and perspectives about resilience. Translating resilience concepts into concrete and measurable objectives and outcomes and effectively...

Wind energy’s rapid expansion has led to unintended consequences for wildlife, with migratory bats among the species most at risk. The behavioural mechanisms underlying collisions remain poorly understood, but one hypothesis is that bats are attracted to wind turbine structures. Vision is important to bat orientation and obstacle avoidance, yet it has been relatively understudied in the context of bat–turbine interactions. We hypothesize that light reflected off turbine surfaces could attract bats, acting as a sensory pollutant that may increase collision risk. To test whether reflective...

Understanding drivers of plant diversity and distributions is critical for their conservation, particularly among changing environments. While plants’ responses to disturbances are relatively well-studied, in-depth analyses of how they respond to habitat recovery are surprisingly scarce. This is particularly true for one of the most diverse, sensitive, and threatened plant families: the Orchidaceae. To address this knowledge gap, we evaluated the diversity and distribution of terrestrial orchid species within a recovering tropical forest landscape in the Republic of Palau. We tested the...

Policy makers and planners aim to overcome the “tyranny of small decisions” to address the triple planetary threats of climate change, biodiversity loss, and pollution. However, top-down policies intended to prevent the accumulation of small decisions from undermining collective goods and public infrastructure have removed agency from individuals and caused unintended negative impacts on society. Urban areas are a critical context to examine the role of small decisions because of the extreme diversity and density of decisions and decision-makers within them, their increasing growth...

Conservation entails cultural practices shaped by our worldviews, values, beliefs, and priorities for our interactions with nature. These inform how we categorize which species we want to occur in which landscapes. In Western conservation organizations, conceptualizations of species ‘belonging’ typically align with a dichotomy of native versus introduced species. This is a cultural paradigm, informed by biological considerations, and it is not uniformly shared across different cultures, resulting in varied conceptualizations of species belonging. These conceptualizations may continue to...