Relationships Between Habitat and Snag Characteristics and the Reproductive Success of the Brown-headed Nuthatch (Sitta pusilla) in Eastern Texas.

Habitat use and reproductive success of the Brown-headed Nuthatch (Sitta pusilla Latham) were studied in East Texas during the 2001-2002 breeding seasons. We compared nest cavity selection at used and randomly selected non-used areas. Height of nest trees, midstory density, and percent leaf litter were negatively correlated with nest site selection. Brown-headed Nuthatches showed a strong preference for short snags; yet placed their nest cavity entrances near the top ofthe snags. While nuthatches may be selecting for habitats with little or no midstory density, percent of leaf litter in the nest sites is most likely the consequence of frequent burning. No significant differences among habitat variables and snag characteristics were found between successful and failed nest cavities. Additionally, no habitat variables were correlated with the number of chicks fledged per nest. Predation was the major cause of nest failure in this study

Shear bands and cracking of metallic glass plates in bending

The thickness dependence of yielding and fracture of metallic glass plates subjected to bending is considered in terms of the shear band processes responsible for these properties. We argue that the shear band spacing (and length) scales with the thickness of the plate because of strain relaxation in the vicinity of the shear band at the surface. This is consistent with recent measurements of shear band spacing versus sample size. We also argue that the shear displacements in the shear band scale with the shear band length and plate thickness, thus causing cracks to be initiated in thicker plates at smaller bending strains. This leads to fracture bending strains that decrease markedly with increasing plate thickness, consistent with recent experiments. These results suggest that amorphous metals in the form of foams might have superior ductility and toughness

The Potential of Girdled and 2,4-D-Injected Southern Red Oaks As Woodpecker Nesting And Foraging Sites

Comparisons of extent of decay in southern red oaks (Quercus falcate Michx.) revealed that trees injected with 2.4-D decayed sooner than girdled trees. Internal examinations of treated trees revealed that girdling and injection permitted growth of heartwood-and sapwood-decaying fungi a condition necessary for woodpecker nest cavity excavation. As a result of the delayed decay, girdling produces better woodpecker habitat in southern red oak. Girdled southern red oaks remain standing longer for woodpeckers to use for foraging and nesting sites. Number of snags required to support various percentages of woodpecker population maximums are presented

Combining Citizen Science with Traditional Biotic Surveys to Enhance Knowledge Regarding the Natural History of Secretive Species: Notes on the Geographic Distribution and Status of the Green Salamander (Aneides aeneus) in the Cumberland Mountains of Virginia, USA

The Green Salamander (Aneides aeneus) is a secretive, arboreal cliff specialist distributed discontinuously across the southern and central Appalachian Mountains, USA. While intensively studied in some parts of its range in the Appalachian Plateau  and Blue Ridge Provinces, the distribution of A. aeneus is still poorly understood, particularly in the Cumberland Mountains physiographic province of the Appalachian region. This data deficiency is partly the result of a lack of formal historic surveys across this region, coupled with a high amount of privately owned land that is inaccessible to traditional biotic surveys. We used a combination of citizen science efforts and traditional field surveys to investigate the distribution and status of A. aeneus across the Cumberland Mountains of southwestern Virginia, USA. Local landowners and outdoor recreation enthusiasts reported a relatively high rate of encounters with A. aeneus, verifying the species’ persistence at four historic localities and leading to the discovery of 36 previously unknown populations. Although we are cautious about making inferences about the true conservation status of A. aeneus across this region given the scarcity of current data, these findings suggest that the distribution of A. aeneus in Virginia has been vastly underestimated and that expanded monitoring programs are needed to further ascertain this species’ status. More broadly, our results illustrate the utility of coupling public initiatives with more traditional field surveys to expand the biogeographic knowledge of secretive, difficult-to-study amphibian species. &nbsp

Resin Flow in Loblolly and Shortleaf Pines Used by Red-Cockaded Woodpeckers

We measured resin flow in loblolly (Pinus taeda L.) and shortleaf (Pinus echinata Mill.) pines in stands used by red-cockaded woodpecker, Picoides borealis (Vieillot), in the Angelina and Davy Crockett National Forests in eastern Texas. We also measured resin flow in a mature loblolly pine stand not used by the woodpeckers. Resin flow varied by study area, species, and stand position. In woodpecker stands, pines experiencing low levels of competition seemed better able to tolerate the continual resin drainage associated with red-cockaded woodpecker resin well pecking. In the Angelina National Forest, all new cavity trees excavated during the study were on forest edges. In the non-woodpecker stand, edge trees had significantly better resin flow. These results indicate that the woodpeckers choose trees most likely to be good resin producers. They also indicate that silviculture in loblolly and shortleaf pine stands should favor edge and an open stand habit when red-cockaded woodpeckers are a major management consideration and that potential resin production can be measured in both cavity pines, and pines being considered for red-cockaded woodpecker introduction

Direct liquid extraction surface analysis mass spectrometry of cell wall lipids from mycobacteria: Salt additives for decreased spectral complexity

RationaleLipids are important mycobacterium cell wall constituents; changes are linked with drug resistance. Liquid extraction surface analysis (LESA) enables direct sampling in a highly sensitive manner. Here we describe protocols for the analysis of lipids from bacterial colonies. Lipids form various adducts, complicating spectra. Salt additives were investigated to circumvent this problem.MethodsChloroform:methanol mixtures were studied for lipid extraction and analysis by LESA‐MS. The inclusion of (ESI‐compatible) acetate salts of sodium, potassium or lithium in the extraction solvent was investigated.ResultsWe report the detection of bacterial cell wall lipids from mycobacterial species using LESA for the first time. Sampling protocols were optimised for the use of volatile extraction solvents. The inclusion of acetate salt additives in the sampling solvent significantly reduces spectral complexity in comparison with no additives being used.ConclusionsLESA offers a sensitive technique for bacterial lipid phenotyping. The inclusion of an acetate salt in the sampling solvent drives adduct formation towards a specific adduct type and thus significantly reduces spectral complexity

Mountain lions prey selectively on prion-infected mule deer

The possibility that predators choose prey selectively based on age or condition has been suggested but rarely tested. We examined whether mountain lions (Puma concolor) selectively prey upon mule deer (Odocoileus hemionus) infected with chronic wasting disease, a prion disease. We located kill sites of mountain lions in the northern Front Range of Colorado, USA, and compared disease prevalence among lion-killed adult (≥2 years old) deer with prevalence among sympatric deer taken by hunters in the vicinity of kill sites. Hunter-killed female deer were less likely to be infected than males (odds ratios (OR) = 0.2, 95% confidence intervals (CI) = 0.1–0.6; p = 0.015). However, both female (OR = 8.5, 95% CI = 2.3–30.9) and male deer (OR = 3.2, 95% CI = 1–10) killed by a mountain lion were more likely to be infected than same-sex deer killed in the vicinity by a hunter (p < 0.001), suggesting that mountain lions in this area actively selected prion-infected individuals when targeting adult mule deer as prey items