Nest-site characteristics can have a strong impact on reproductive success in birds. Nest sites should simultaneously protect from predators, offer shelter and provide a favourable microclimate. We studied the relationship between three agents of natural selection (predators [i.e. Adders and birds/mammals], snowfall and microclimate), nest-site characteristics and reproductive success to determ...

We studied the effect of the general structure of the nest plant, especially the presence of thorns, and the structural homogeneity of the nest patch, on the vulnerability of nests to predation, using natural and artificial nests. Artificial nests placed in non-thorny plants had a significantly lower predation rate and higher daily survival rate than those in thorny plants. The addition of a ‘t...

Social insect colonies use interactions among workers to regulate collective behavior. Harvester ant foragers interact in a chamber just inside the nest entrance, here called the 'entrance chamber'. Previous studies of the activation of foragers in red harvester ants show that an outgoing forager inside the nest experiences an increase in brief antennal contacts before it leaves the nest to for...

Modelling and mapping of hooded warbler (Wilsonia citrina) nesting habitat in forests of southern Ontario were conducted using Ikonos and Landsat data. The study began with an analysis of skyward hemispherical photography to determine canopy characteristics associated with nest sites. It showed that nest sites had significantly less overhead canopy cover and larger maximum gap size than in non-...

Nest predation is a primary cause of nesting mortality for many bird species (Sk&h 1949, 1966; Nice 1957; Ricklefs 1969: Nilsson 1984). Food limitation and competition also can affect nesting success (see reviews in Martin 1986, 1987). However, the primary role of nest predation in nesting mortality suggests that it can be a strong agent of selection on bird species and assemblages; when nest p...

Nest predation is a critical component in avian productivity and typically is the leading cause of nest failure for most birds. Several landscape features are thought to drive the behavioral interaction between northern bobwhite (Colinus virginianus; e.g., nest placement) and their predators (e.g., search methods for food acquisition). In order to understand habitat characteristics influencing ...

Nest predation risk generally increases nearer forest-field edges in agricultural landscapes. However, few studies test whether differences in edge contrast (i.e. hard versus soft edges based on vegetation structure and height) affect edge-related predation patterns and if such patterns are related to changes in nest conspicuousness between incubation and nestling feeding. Using data on 923 nes...

Assessment of foreign/second language (L2) oral proficiency is known to be complex and influenced by the local context. In Sweden, extensive assessment guidelines for National English Speaking Test (NEST) are offered teachers, who act as raters their own students’ performances on this high-stakes L2 (OP) test. Despite guidelines, teachers commonly construct NEST scoring rubric. The present stud...

OBJECTIVE To compare loneliness, depressive symptoms and major depressive episodes between empty-nest and not-empty-nest older adults in rural areas of Liuyang city, Hunan, China. METHODS A cross-sectional multi-stage random cluster survey was conducted from November 2011 to April 2012 in Liuyang, China. A total of 839 rural older residents aged 60 or above completed the survey (response rate...

Many ant species construct subterranean nests. The presence of their nests may explain soil respiration "hot spots", an important factor in the high CO2 efflux from tropical forests. However, no studies have directly measured CO2 efflux from ant nests. We established 61 experimental plots containing 13 subterranean ant species to evaluate the CO2 efflux from subterranean ant nests in a tropical...