Treesearch

Human-facilitated introductions of nonnative populations can lead to secondary contact between allopatric lineages, resulting in lineage homogenisation or the formation of stable hybrid zones maintained by reproductive barriers. We investigated patterns of gene flow between the native Sacramento Valley red fox (Vulpes vulpes patwin) and introduced conspecifics of captive-bred origin in California's Central Valley. Considering their recent divergence (20–70 kya), we hypothesised that any observed barriers to gene flow were primarily driven by pre-zygotic (e.g. behavioural differences)...

The first record of captive-bred red foxes (Vulpes vulpes) dates to 1896 when a breeding enterprise emerged in the provinces of Atlantic Canada. Because its domestication happened during recent history, the red fox offers a unique opportunity to examine the genetic diversity of an emerging domesticated species in the context of documented historical and economic influences. In particular, the historical record suggests that North American and Eurasian farm-bred populations likely experienced different demographic trajectories. Here, we focus on the likely impacts of founder effects and...

Characterizing natal dispersal can help manage the spread of invasive species expanding their ranges in response to land use and climate change. The Barred Owl (Strix varia) is a prominent example of an apex predator undergoing a rapid range expansion, having spread from eastern to western North America where it is now hyperabundant - threatening the Northern Spotted Owl (Strix occidentalis caurina) with extinction and potentially endangering many other native species. We attached satellite tags to 31 Barred Owl juveniles at the southern leading edge of the Barred Owl’s expanding range in...

The grassland biome is an important sink for atmospheric methane (CH4), a major greenhouse gas. There is considerable uncertainty in the grassland CH4sink capacity due to diverse environmental gradients in which grasslands occur, and many environmental conditions can affect abiotic (e.g., CH4diffusivity into soils) and biotic (e.g., methanotrophy) factors that determine spatial and temporal CH4dynamics. We investigated the relative importance of a soil's gas diffusivity versus net methanotroph activity in 22 field plots in seven sites distributed across the US Great Plains by making...

In Utah, and much of the Intermountain West, riparian forests make up a small percentage of the landscape but provide disproportionately large ecological functions and societal values. Since the early 1800s, Utah’s riparian forests have experienced shifts in natural disturbance regimes, changes in flow regimes and water tables, changes in vegetation composition and structure, introduction of exotic plant and animal species, and land use conversion. Today, managers need science-based guidance to assess ecological integrity, detect causes of degradation, and select appropriate methods for...

Insects and diseases are significant disturbance agents in many forests. In some places, annual surveys by observers in aircraft are valuable resources but can have significant issues that result in gaps. Using remotely sensed data is therefore attractive. Here we provide a review of this topic that is novel in several ways. We describe tree, stand, and landscape responses to insects and diseases, then link these responses to remote sensing technologies and methods for detection and attribution. We focus on insects and diseases that cause substantial damage and mortality to conifers in the...

In multi-carnivore systems individuals must forage and reproduce while also competing with other carnivores and avoiding intraguild predation. These interactions may vary by strength and scales across different ecosystems. We used occupancy analyses and attraction-avoidance indices to assess large- and fine-scale interactions, respectively, between Cougars (Puma concolor), Bobcats (Lynx rufus), and Coyotes (Canis latrans) in northeast Oregon based on data from camera traps set during the summer and fall of 2016 and 2017. To determine the importance of habitat preferences and spatial...

If there is one common experience shared by all scientists, regardless of subdiscipline, it is the gauntlet of peer review. We all know the painful experience of rejection, the frustration of acquiescing to reviewers’ demands, and the many months that can sometimes elapse between the submission of and first decision on a paper. But for many, it is the peer-review process that adds the necessary ingredient of rigor - the stamp of approval - to science. For instance, science journalists primarily cover peer-reviewed studies, and the court systems consider peer-reviewed science to be the gold...

Advances in hierarchical modeling have improved estimation of ecological parameters from count data, especially those quantifying population abundance, distribution, and dynamics by explicitly accounting for observation processes, particularly incomplete detection. Even hierarchical models that account for incomplete detection, however, cannot compensate for data limitations stemming from poorly planned sampling. Ecologists therefore need guidance for planning count‐based studies that follow established sampling theory, collect appropriate data, and apply current modeling approaches to...

Background: Studies of animal habitat selection are important to identify and preserve the resources species depend on, yet often little attention is paid to how habitat needs vary depending on behavioral state. Fishers (Pekania pennanti) are known to be dependent on large, mature trees for resting and denning, but less is known about their habitat use when foraging or moving within a home range.Methods: We used GPS locations collected during the energetically costly pre-denning season from 12 female fishers to determine fisher habitat selection during two critical behavioral activities:...