Treesearch

The genus Macrochelys (Alligator Snapping Turtles) is the only extant turtle clade whose members possess supramarginal scutes (Joyce 2016). The extinct genera Proganochelys (Ascarrunz and Sánchez-Villagra 2022), Platychelys (Sullivan and Joyce 2017), and Boremys (Joyce and Lyson 2015) also all possessed supramaginal scutes. However, supramarginals in these four genera do not likely represent homologous structures. Platychelys is a stem-pleurodire (Sullivan and Joyce 2017) unlike the cryptodires Macrochelys and Boremys, whereas Proganochelys is an early testudinatan that may represent a...

Family forest owners (FFOs) control a plurality of forestland in the United States, and the decisions these landowners make have a profound impact on the landscape. Most research on FFOs consists of cross-sectional studies, although many of these recognize the importance of capturing long-term trends to understand whether and how FFO attitudes, behaviors, and general characteristics are changing. We use data from the 2006, 2013, and 2018 iterations of the USDA Forest Service, National Woodland Owner Survey (NWOS), with a bootstrapping approach to identify significant changes across these...

Population dynamics of migratory species are influenced by land use and climate patterns experienced across the full annual cycle. Identifying environmental factors influencing productivity, survival, and their relative contributions to abundance and population growth is critical for the recovery and management of at-risk species in the face of continuing global change. The golden-cheeked warbler (Setophaga chrysoparia) is an endangered passerine that breeds exclusively in the mixed Ashe juniper (Juniperus ashei)–oak (Quercus) woodlands of Central Texas, USA, and winters at high elevations...

Wildfires can dramatically modify the hydrologic and erosion response of ecosystems, increasing risks to population and assets downslope of fire affected hillslopes. This applies especially to volcanic areas in fire-prone regions which often exhibit steep terrain and high population densities. However, the effects of fire on key hydrologic and erosion parameters, which are critical for modelling runoff-erosion processes, predicting related post-fire risks and for selecting effective mitigation measures, have not been extensively assessed in this terrain type. Here we evaluate water erosion...

On dryland hillslopes, vegetation water availability is often subsidized by the redistribution of rainfall runoff from bare soil (sources) to vegetation patches (sinks). In regions where rainfall volumes are too low to support spatially continuous plant growth, such functional connectivity between bare soil and vegetated areas enables the establishment and persistence of dryland ecosystems. Increasing the connectivity within bare soil areas can intensify runoff and increase water losses from hillslopes, disrupting this redistribution and reducing the water available to sustain ecosystem...

Wild pigs (Sus scrofa), which are invasive in many regions globally, can alter ecosystems and compete with native species through interference competition and resource exploitation. Wild pig impacts on other species may increase with greater niche overlap, which could vary over time based on environmental conditions, resource availability, or biological traits like diet, especially as seasonal variation in wild pig diet has been widely documented. A limited number of studies have assessed spatial or temporal overlap between native species and invasive wild pigs, with only a handful...

Understanding whether invasive and native species compete for shared resources where they co-occur is essential for mitigating the negative impacts of invasive species on native ecosystems. Here, we examined how the presence and density of an invasive species, wild pigs (Sus scrofa), affect native white-tailed deer (Odocoileus virginianus; hereafter, deer) on the Savannah River Site, SC, USA. We examined potential changes in deer areas of use, temporal overlap, and occupancy to evaluate the effects of wild pig occurrence and density on deer space use, diel activity, and co-occurrence with...

Lead mining in the Southeast Missouri Lead Mining District began in the 1700s and continued for nearly 300 years; the waste piles associated with smelting, mining, and milling of lead ores have released metal residues that have contaminated soil and water in the region. Previous studies in the district have indicated potential harm to wildlife, including birds, because of elevated lead concentrations associated with mining. Exposure to soil-borne lead was correlated with elevated lead concentrations in tissues, inhibition of δ-aminolevulinic acid dehydratase (δALAD), and renal lesions in...

Accurate observation of hillslope groundwater storage and instantaneous recharge remains difficult due to limited monitoring and the complexity of mountainous landscapes. We introduce a novel storage-discharge method to estimate hillslope recharge and the recharge ratio—the fraction of precipitation that recharges groundwater. The method, which relies on streamflow data, is corroborated by independent measurements of water storage dynamics inside the Rivendell experimental hillslope at the Eel River Critical Zone Observatory, California, USA. We find that along-hillslope patterns in...

While tree plantations have increased globally, there is growing interest in restoring plantations to native ecosystems. Restoration efforts may be more successful when tree species native to original ecosystems are planted instead of species that are either introduced or native, but off site. Plantations of red pine (Pinus resinosa Ait.) in the western Great Lakes region of North America were commonly established on red pine sites, often after agricultural clearing and abandonment. Red pine is the only species in the overstory, compared to 10 or more species in red pine woodlands....