Treesearch

The body size of aquatic vertebrates is declining across populations and ecosystems worldwide owing to warmer water temperature and changing streamflow. In freshwaters, the effects of stream network position and density-dependent factors on body size are less understood. We used an extensive dataset spanning 41 stream sites over 7 years to evaluate how density-dependent and density-independent factors influence the size of two top predators in small watersheds, Coastal Cutthroat Trout Oncorhynchus clarkii clarkii and Coastal Giant Salamanders Dicamptodon tenebrosus. We tested three...

Computer vision models show great promise for assisting researchers with rapid processing of ecological data from many sources, including images from camera traps. Access to user-friendly workflows offering collaborative features, remote and local access, and data control will enable greater adoption of computer vision models and accelerate the time between data collection and analysis for many conservation and research programs. We present Njobvu-AI, a no-code tool for multiuser image labeling, model training, image classification, and review. Using this tool, we demonstrate training and...

Habitat suitability models (HSMs) play an important role in conservation planning by identifying areas for habitat management and guiding surveys for population discovery and monitoring. The wood turtle Glyptemys insculpta is a riverine turtle that uses both riparian and upland environments. Habitat loss and degradation have resulted in range‐wide declines of this species throughout the United States. Previous HSMs have been developed for wood turtles; however, no published HSM we are aware of exists for their range in the midwestern United States (including parts of Iowa, Michigan,...

In the moist, coniferous forests of Oregon and Washington, a dense network of headwater streams supports high levels of amphibian species endemism and diversity, including the torrent salamanders (Rhyacotriton spp.). The Columbia and Cascade torrent salamanders (R. kezeri and R. cascadae, respectively) are species of greatest conservation need, but current information is insufficient for an adequate status assessment. We aimed to determine the current distributional extent, occurrence, and abundance of both species across their respective ranges, and to characterize watershed-scale habitat...

Ecological community data are used to infer levels of environmental stressors; for example, epiphytic lichen communities can be used to estimate levels of air pollutants. If stressors are so severe that the community of interest disappears altogether, then “empty” plots are recorded. The problem compounds when multiple environmental stressors strongly influence the community. We explore this problem using simulated data and a case study of epiphytic lichens in the Sierra Nevada mountains of the United States. This area experiences relatively high amounts of nitrogen (N) deposition that can...

Aim: To map the probability of landscape use of invading barred owls (Strix varia) across the range of the threatened northern spotted owl (S. Occidentallis Caurina) in the Pacific Northwest, USA, identifying environmental drivers of barred owl landscape use to inform targeted management interventions.Location: Forests of the Pacific Northwest, USA.Taxon: Barred Owl (Strix varia).MethodsWe deployed 4081 autonomous recording units (ARUs) within 1027 randomly selected long-term monitoring sites consisting of 5-km2 hexagons in 2023. We processed audio recordings using convolutional neural...

Public land management relies on accurate visitor counts in order to understand and mitigate environmental impacts and to quantify the value of ecosystem services provided by natural areas. We build and test predictive visitation models suitable for publicly-managed parks, open space, and other protected lands based on multiple sources of digital mobility data including geotagged posts to social media platforms, community science observations, and a mobile device location dataset from a commercial vendor. Using observational visitation data series from the United States’ National Park...

Across the Pacific Northwest’s fire-prone landscapes, where human activity accounts for about 58 percent of all ignitions, socioeconomic factors point to why some communities face repeated blazes and some remain untouched. These patterns raise critical questions about the allocations of wildfire resourcesAfter analyzing more than 104,000 wildfire ignitions across Oregon and Washington from 1992–2018, researchers Jeff Kline, Mindy Crandall, and Caitlyn Reilley reveal a paradox in wildfire risk management. While current risk assessment tools predict higher wildfire hazard in well-resourced...

Wild foods are critical to the food security of billions of people worldwide, yet the ecological mechanisms that promote wild food system stability remain poorly understood. Within complex food webs, ecological theory predicts that nonhuman consumers can maintain more stable consumption rates by foraging on multiple resources that vary asynchronously in their availability across space and time. These so-called portfolio effects may also sustain more stable harvest rates by humans in wild food systems. We analyzed wild food harvest patterns for 46 isolated rural communities in southern...

The marbled murrelet (Brachyramphus marmoratus) is a seabird of conservation concern that nests in late-successional, old-growth forests in Oregon, Washington, and California, USA. Traditional audio-visual surveys have been the standard method for detecting murrelets in forests. Given that murrelets can be extremely cryptic in forest environments, audio-visual surveys are difficult, time consuming, and expensive to conduct. Passive acoustic monitoring (PAM) may be a useful and cost-effective alternative. Using a paired murrelet survey design, we compared detection probabilities across 88...