Treesearch

Because riparian ecosystems are highly valued for their diverse ecological services, past and ongoing disturbances in riparian zones have led to extensive restoration efforts, litigation, and compliance monitoring of the effects of livestock grazing. Better understanding of the factors that influence cattle riparian use, especially in landscapes supporting threatened or endangered fish, could lead to improved predictions of management outcomes and riparian recovery for sustainable grazing systems. Although published models predict habitat selection by cattle, there is a gap in our understan...

The Fender’s blue butterfly (Icaricia icarioides fenderi) is a federally listed threatened species occurring in the Willamette Valley, Oregon. The species depends on intact, native prairie environments with plants used for nectar sources and egg-laying. This report provides photos of selected locations with the species presence and provides views of conditions and changes under seasonal and management activities, particularly focused on conditions providing suitable habitat.

The repatriation of species is common, especially in conservation efforts aimed at restoring trophic interactions. Whether the Eltonian niches of restored species are conserved in reassembled ecological communities is largely unknown. Within mammalian carnivores, we hypothesized that the Eltonian niches of sympatric competitors would be structured by trophic facilitation from subsidies provided by large carnivores (i.e. carrion) and humans (i.e. food subsidies). Using stable isotopes (δ13C, δ15N), we quantified the Eltonian niches of an apex predator, the grey wolf Canis lupus and two...

Human-induced land use practices can result in the bioaccumulation of metals in turtles. We assessed relationships between land use and pollutant concentrations in painted turtles (Chrysemys picta) and snapping turtles (Chelydra serpentina) through non-destructive tissue sampling across 22 sites within a mixed-use watershed in north-central West Virginia, U.S.A.. Metal concentrations were consistently higher in nails than in blood. Selenium levels in soil and turtle nails were positively correlated with proximity to mine land. Lead levels in turtle nails were positively correlated with Pb...

Opportunities are rare to study ecological primary succession and physical channel development in brand-new streams. An exception exists in streams recently formed atop extensive pyroclastic materials deposited during the 1980 eruption of Mount St Helens (USA), an area known as the Pumice Plain. Recent work demonstrated unexpectedly high diversity of benthic invertebrates in Pumice Plain streams at <4 decades post eruption, both within and among streams. Given the ecological importance of the hyporheic zone (HZ), we asked if differential development of HZs, both physically and biologically,...

In recent decades, evidence of interactions between aboveground and belowground (i.e., soil) subsystems has accumulated. The effects of aboveground vertebrates on belowground communities have traditionally focused on plant-mediated pathways, but we show that aboveground vertebrates impact belowground communities and ecological functions without plant-mediated pathways via both consumptive and non-consumptive processes. We then show that mobile, aboveground vertebrates have significant but often unrealized potential to structure soil communities from local to macroecological scales by...

The California Condor (CACO; Gymnogyps californianus) is a critically-endangered apex scavenger with multiple reintroduction sites providing population reinforcement. Spent lead ammunition pollution in CACO food (i.e., carrion and gut piles) was most likely responsible for the decline of CACO populations in the twentieth century and continues to be the leading source of condor mortality. To aid condor recovery decisions for the California population, numbering approximately 200 in early 2024, we present results from a female-only, individual-based life cycle model. We simulated future CACO...

Volcanic provinces are among the most active but least well understood landscapes on Earth. Here, we show that the central Cascade arc, USA, exhibits systematic spatial covariation of topography and hydrology that are linked to aging volcanic bedrock, suggesting systematic controls on landscape evolution. At the Cascade crest, a locus of Quaternary volcanism, water circulates deeply through the upper ∼1 km of crust but transitions to shallow and dominantly horizontal flow as rocks age away from the arc front. We argue that this spatial pattern reflects a temporal state shift in the deep...

Monitoring vegetation response to valley-scale floodplain restoration to evaluate effectiveness can be costly and time-consuming. We used publicly available National Agriculture Imagery Program (NAIP) data and commonly used ArcGIS software to assess land cover change over time at five study sites located in semi-arid environments of eastern Oregon and north-central California. Accuracy assessments of our unsupervised classifications were used to evaluate effectiveness. Overall accuracy across sites and years ranged from 64.2% to 89.2% with mean and median accuracy of 79.1% and 80.6%,...

At first glance, wood turtles may look like any other aquatic turtle—but they’re actually quite unique. Their carapace features elevated, concentric rings, resembling growth rings associated with trees. Unlike most other turtles, this semi-aquatic, freshwater species spends a substantial amount of time in terrestrial environments where it’s found in the upper midwestern and northeastern portions of the U.S. and southeastern Canada. Wood turtles are found predominantly in river systems with clean, highly oxygenated and medium- to fast-flowing streams for brumation—similar to hibernation in...