Using radios and models to assess extinction risk in a Neotropical highland Cinclodes What do the patterns of space use tell us about the risk of extinction of a species? This relationship is certainly strong. The number of individuals (population size) and the geographical range are among the main criteria for assessing the conservation status of a species by the IUCN (International Union for Conservation of Nature), and the knowledge about the habitats used is crucial for protecting the natural resources their need to survive.... continue reading.
Apparent survival of tropical birds in a wet, premontane forest in Costa Rica Downpours, blustery winds, and a damp fog are not the best weather for doing fieldwork in Parque Nacional Volcán Tenorio in Costa Rica. Although the inclement weather isn’t great for behavioral observations of White-ruffed Manakins, it does provide an excellent opportunity to write about our recent paper in the Journal of Field Ornithology – “Apparent survival of tropical birds in a wet, premontane forest.”... continue reading.
Kicked out or moving out? Fledging behaviors of grassland songbirds Leaving one’s family home is a momentous occasion for all children, human or otherwise, but for birds it’s not well-known how much of this event is up to the parents’ influence or the nestlings’ choice. This is especially true in the grasslands, where birds build well-camouflaged nests down among the grasses and low shrubs, and where sightlines can stretch for miles in all directions, making undetected observation by researchers a logistical challenge.... continue reading.
Researchers use thermal cameras to detect roosting birds Where do small birds sleep? Mostly in trees is the short answer, but as so often occurs in ecology, there is more to the story…... continue reading.
Spatial and temporal factors associated with nest survival of Gray Flycatchers in managed ponderosa pine forests During our research on cavity-nesting birds in the Wenas Valley, WA, we observed a breeding population of Gray Flycatchers. The species, a Neotropical migrant, has a widespread breeding distribution in the arid and semi-arid regions of the western United States. As a result of climate change, many Neotropical bird species are expected to shift their distributions northward as regional temperatures increase. A quick literature search revealed that few studies have looked at the nesting ecology of Gray Flycatchers and none have been conducted in the expanded northern portion of its range. For example, in 1972, the species was found breeding for the first time... continue reading.
Recommendations for selecting an arthropod sampling method Since many birds are insectivorous, their study often requires an accurate understanding of the arthropod prey community, including studies into resource selection, dietary overlap, and drivers of population density. However, ornithologists struggle to properly apply arthropod sampling techniques for a variety of reasons. First, there are many different arthropod sampling methods to choose from, each with their own problems and biases. Secondly, some habitats, such as forests, are structurally complex, with many different microhabitats that likely have different arthropod communities. Therefore, the central problem for ornithologists selecting a sampling method is that the arthropod community sampled by the selected method must align with the community of arthropods available to the study species.... continue reading.
A review of threshold responses of birds to landscape changes across the world Habitat loss is recognized as having one of the most severe impacts of human activity on biodiversity. Threshold of habitat cover is a concept used in ecology and landscape ecology to define the breaking point beyond which species are locally lost. Identifying such thresholds is an important task not only for scientists to predict the state of a given ecosystem, but it also has great potential for environmental policy-making and conservation practice. A new review by Isabel Melo and colleagues published in the Journal of Field Ornithology compiles all the 31 studies of habitat cover threshold responses dealing with birds worldwide since the threshold concept was first... continue reading.