Treesearch

Accurate census is essential for endangered plant management, yet lack of resources may make complete on-the-ground census difficult to achieve. Accessibility, especially for species in fragile habitats, is an added constraint. We examined the feasibility of using UAV (unmanned aerial vehicle, drone)-based imagery for census of an endangered plant species, Arctomecon humilis (dwarf bear-poppy), an herbaceous perennial gypsophile endemic of the Mojave Desert, USA. Using UAV technology, we captured imagery at both 50-m altitude (census) and 15-m altitude (validation) at two populations,...

Landscape resistance is often disregarded in studies of range expansions and population connectivity. To assess those effects, we simulated the expansion of the Egyptian mongoose (Herpestes ichneumon) in relation to landscape resistance through kernel resistance modeling, confronting it with previously published data regarding the observed pattern of expansion and genetic diversity of the population in Portugal.We modeled population expansion as a function of shrub cover and elevation through iterative simulation of a resistance model and a null model. We then performed an overlap analysis...

We have read Cruz and Alexander’s comments regarding our manuscript titled ‘‘Evaluating Crown Fire Rate of Spread Predictions from Physics-Based Models’’ [1] and appreciate the opportunity to respond to their comments. In our original manuscript [1], we presented an evaluation of crown fire rate of spread predictions from two physics-based wildland fire behavior models: FIRETEC and the Wildland Urban Interface Fire Dynamics Simulator (WFDS). Our approach, as outlined in our original paper, relied upon using a previously published dataset of real-world crown fires, hereafter referred to as...

A facilitated audience discussion on emerging needs for oak management and research at the Oak Symposium revealed several interrelated themes. The audience identified needs that fell into three primary categories: ● Applying research; ● Adoption of existing knowledge and technology; and ● Infrastructure/available markets.

Globally, biodiversity declines have occurred at alarming rates across a wide array of taxa. Amphibians and reptiles (known collectively as herpetofauna), represent two taxa that have declined considerably over the past three decades. A variety of stressors, including landscape change, habitat destruction, emerging pathogens, illegal collection, and climate change all contribute synergistically to impact herpetofaunal populations. Of these threats, habitat alteration and destruction represent acute stressors that have increased concomitantly with the rise in global human population....

Increasing the capacity of communities on the rural-urban fringe to accommodate sustainable growth is a key concern among resource management agencies. Decisions about the future of these landscapes involve difficult tradeoffs that underscore the importance of incorporating diverse stakeholder values and preferences into planning efforts. We assessed residents' preferences for exurban growth alternatives in two Midwestern U.S. counties – Jasper County, IA and Will County, IL – that have strong agrarian roots and lie at the fringe of rapidly-expanding metropolitan areas. Using a choice...

The spotted lanternfly (SLF), Lycorma delicatula (White) (Hemiptera: Fulgoridae), is native to China and Vietnam. An early report that SLF occurs in India was described by the author as "doubtful" (Distant 1906); nevertheless, some papers have reported India within this insect's native range. SLF has also spread to Japan and Korea in recent decades, with the DNA in those populations matching very closely to populations in China (Kim et al. 2013). SLF was first reported in the USA in 2014, in Berks County, Pennsylvania, northwest of Philadelphia (Barringer et al. 2015, Dara et al. 2015). As...

To better understand forest carbon (C) storage patterns, C budgets were constructed and contrasted among four stands of different vegetation, elevation, and disturbance histories from the northern Sierra Nevada of California, USA. The True-fir stand, considered to be undisturbed and at a higher elevation (1820 m), stored substantially more C than the three stands at lower elevation (1360–1430 m) and that had sustained various levels of disturbance. The Mixed Conifer stand was minimally disturbed by thinning 27 yr ago. The Oak stand was moderately disturbed by two fires in the past 17 yr....

Bark beetles are primary disturbance agents in western US forests. Outbreaks affect goods and services associated with forest ecosystems including timber, water, fish and wildlife habitats and populations, recreation opportunities, and many others. They can also affect wildfire behavior and its intensity. Assessments and evaluations of such impacts are important information to land managers, policy makers, and forest stakeholders, as well as to the broader public. Arriving at a complete and accurate assessment and evaluation is a complex process that necessarily considers effects and...

Coexistence of ecologically similar species can be maintained by partitioning along one or more niche axes. Three-dimensional structural complexity is central to facilitating resource partitioning between many forest species, but is underrepresented in field-based studies. We examined resource selection by sympatric northern spotted owls (Strix occidentalis caurina), a threatened species under the US Endangered Species Act, and nonnative barred owls (S. varia) in western Oregon, USA to explore the relative importance of canopy heterogeneity, vertical complexity of forest, and abiotic...