Winter Home Range and Habitat Use of the Virginia Northern Flying Squirrel (Glaucomys sabrinus fuscus)

We radio-tracked two male and one female Virginia northern flying squirrels (Glaucomys sabrinus fuscus) in the Allegheny Mountains of West Virginia at Snowshoe Mountain Resort, in winter 2003 and Canaan Valley National Wildlife Refuge in winter 2004, respectively, to document winter home range and habitat use in or near ski areas. Male home range size in the winter was larger than that reported for males during summer and fall, whereas the female home range we observed was smaller than those reported for summer and fall. However, winter habitat use was similar to summer and fall habitat use reported in other studies. Virginia northern flying squirrels foraged and denned in both red spruce (Picea rubens)-dominated forests and northern hardwood forests; however, selection of red spruce-dominated forests and open areas was greater than expected based on availability. Use of northern hardwood forest occurred less than expected based on availability. Male squirrels denned near, and routinely crossed, downhill ski slopes and unimproved roads during foraging bouts, whereas the female approached, but did not cross forest edges onto roads or trails

Ending hunger in Africa prospects for the small farmer

"In contrast to widely held uncertainties about Sub-Saharan Africa's ability to meet the Millennium Development Goals (MDGs), recent successes in African smallholder farming show that agriculture could play a key role in helping the region reach those goals. African governments and the donor community have recognized this potential and have pledged to help generate agricultural progress. This policy brief considers recent trends in poverty, malnutrition, and growth; outlines some of the challenges to boosting agricultural growth; and highlights cases of agricultural success in specific countries. By learning from case studies of smallholder success and building on the new enthusiasm of African governments, donors and their African partners can ensure that agriculture's role in meeting the MDGs is fully realized." from TextMillenium Development Goals ,

Ending hunger by 2050

"To end hunger and prevent the recurrence of famine and starvation, we need to take the following steps: invest in public health, child nutrition, education, women's and girls' social status, and other components of human capital; reform public institutions and create innovative funding and partnership arrangements; change government policies at all levels to be both pro-poor and pro-growth; increase funding for scientific and technological research to boost agricultural production and efficiency; and develop specific policies and institutions to deal with environmental degradation caused by population growth. The international community, national governments, nongovernmental organizations (NGOs), and the private sector must cooperate to bring about these changes, which reach beyond redistribution programs, narrowly focused market-oriented solutions, or campaigns based solely on local self-reliance." from text

Propagation of optical excitations by dipolar interactions in metal nanoparticle chains

Dispersion relations for dipolar modes propagating along a chain of metal nanoparticles are calculated by solving the full Maxwell equations, including radiation damping. The nanoparticles are treated as point dipoles, which means the results are valid only for a/d <= 1/3, where a is the particle radius and d the spacing. The discrete modes for a finite chain are first calculated, then these are mapped onto the dispersion relations appropriate for the infinite chain. Computed results are given for a chain of 50-nm diameter Ag spheres spaced by 75 nm. We find large deviations from previous quasistatic results: Transverse modes interact strongly with the light line. Longitudinal modes develop a bandwidth more than twice as large, resulting in a group velocity that is more than doubled. All modes for which k_mode <= w/c show strongly enhanced decay due to radiation damping.Comment: 26 pages, 7 figures, 2 tables. to appear in Phys. Rev.

Analyzing large-scale conservation interventions with Bayesian hierarchical models: a case study of supplementing threatened Pacific salmon.

Myriad human activities increasingly threaten the existence of many species. A variety of conservation interventions such as habitat restoration, protected areas, and captive breeding have been used to prevent extinctions. Evaluating the effectiveness of these interventions requires appropriate statistical methods, given the quantity and quality of available data. Historically, analysis of variance has been used with some form of predetermined before-after control-impact design to estimate the effects of large-scale experiments or conservation interventions. However, ad hoc retrospective study designs or the presence of random effects at multiple scales may preclude the use of these tools. We evaluated the effects of a large-scale supplementation program on the density of adult Chinook salmon Oncorhynchus tshawytscha from the Snake River basin in the northwestern United States currently listed under the U.S. Endangered Species Act. We analyzed 43 years of data from 22 populations, accounting for random effects across time and space using a form of Bayesian hierarchical time-series model common in analyses of financial markets. We found that varying degrees of supplementation over a period of 25 years increased the density of natural-origin adults, on average, by 0-8% relative to nonsupplementation years. Thirty-nine of the 43 year effects were at least two times larger in magnitude than the mean supplementation effect, suggesting common environmental variables play a more important role in driving interannual variability in adult density. Additional residual variation in density varied considerably across the region, but there was no systematic difference between supplemented and reference populations. Our results demonstrate the power of hierarchical Bayesian models to detect the diffuse effects of management interventions and to quantitatively describe the variability of intervention success. Nevertheless, our study could not address whether ecological factors (e.g., competition) were more important than genetic considerations (e.g., inbreeding depression) in determining the response to supplementation

Observations of Long-tailed Weasel, Mustela frenata, Hunting Behavior in Central West Virginia

Using infrared video-surveillance systems during 1999&ndash;2000, we observed attempts by two individual Long-tailed Weasels (Mustela frenata) to depredate female Ruffed Grouse (Bonasa umbellus) and their clutch of eggs. Neither female was captured despite Long-tailed Weasel attacks on multiple nights, but all eggs from one nest were either consumed or cached over a two-night period. Although Long-tailed Weasels have been shown to return quickly to areas of abundant prey, return visit behavior to locations where weasels were unsuccessful or only partially successful are poorly described

Observations of Long-tailed Weasel, Mustela frenata, Hunting Behavior in Central West Virginia

Using infrared video-surveillance systems during 1999&ndash;2000, we observed attempts by two individual Long-tailed Weasels (Mustela frenata) to depredate female Ruffed Grouse (Bonasa umbellus) and their clutch of eggs. Neither female was captured despite Long-tailed Weasel attacks on multiple nights, but all eggs from one nest were either consumed or cached over a two-night period. Although Long-tailed Weasels have been shown to return quickly to areas of abundant prey, return visit behavior to locations where weasels were unsuccessful or only partially successful are poorly described

Physical Condition, Sex, and Age-Class of Eastern Red-Backed Salamanders ( Plethodon cinereus

Nonforested habitats such as open fields and pastures have been considered unsuitable for desiccation-prone woodland salamanders such as the Eastern Red-backed Salamander (Plethodon cinereus). Recent research has suggested that Plethodon cinereus may not only disperse across but also reside within open habitats including fields, meadows, and pastures. However, presence and high densities of P. cinereus within agriculturally disturbed habitats may be misleading if these populations exhibit atypical demographic characteristics or decreased physical condition relative to forest populations. We surveyed artificial cover boards from 2004-2005 to compare physical condition, sex ratios, and age-class structure of P. cinereus among woodland, woodland-meadow edge, silvopasture, and meadow sites in the central Appalachian Mountains of southern West Virginia. Physical condition of salamanders was not significantly different among the four habitats. Furthermore, adult sex ratios of P. cinereus typically were not significantly different from 1 : 1 and were similar between forested and non-forested sites, although populations within silvopastures were biased towards females. However, adult salamanders were significantly more abundant than juveniles in all habitat types, with differences most pronounced within meadow habitats. Our study indicates that relatively small, non-forested habitats such as silvopastures and meadows may not adversely affect the overall physical condition or sex ratios of Plethodon cinereus. However, the paucity of juveniles within disturbed meadows indicates that these agriculturally modified habitats may negatively impact reproduction or that immature salamanders are at a physiological or competitive disadvantage in comparison to adults, particularly when surface cover is limited