Acoustic signalling mediates key animal behaviours, but the factors driving inter- and intra-specific variation remain elusive, especially in non-learning suboscine birds. Acoustic traits may evolve to signal an individual’s quality through a process termed honest signalling. Most studies on bird song evolution via honest signalling focus on oscine bird species (song learners) while fewer evaluate honest signalling in suboscines.
This chapter from The Codex of the Endangered Species Act, Volume II: The Next Fifty Years describes how genetic information is used to inform decision-making for the Endangered Species Act. In one section of this chapter (page 4 of the PDF, page 162 of the book), the use of genomics to differentiate between subspecies of willow flycatcher (Empidonax traillii) is described.
An in-depth System for Assessing Vulnerability of Species modeling effort that looks at two dozen threatened and endangered species and how they may be affected by a changing climate. The authors provide a numerical scale of risk based on possible changes in habitat, physiology, phenology, and interactions across a scale of uncertainties. Results and discussion of the most critical factor for each species are presented.
A Maximum Entropy presence-only habitat model developed to look at future climate-based habitat changes (2030, 2060, 2090) in the Rio Grande Corridor in NM for Lucy’s warbler, Southwestern willow flycatcher, and the Western yellow-billed cuckoo. Biophysical characteristics like distance to water proved to be more important than climate in habitat suitability predictions, but climate led to 60% declines of suitable habitat by 2090. For all species, suitable habitat tended to shrink over time within the study area leaving a few core areas of high importance.
A look at the potential for southwestern willow flycatcher (Empidonax traillii extimus) adaptations to rising temperatures from an ecological genomics perspective. Compared to other willow flycatcher populations results indicate small, fragmented populations of the southwestern willow flycatcher will have to adapt most to keep pace with climate change.
Habitat factsheets and scorecards describe the habitat needs and behaviors of species of interest in the Colorado State Wildlife Action Plan. This particular document is for Southwestern Willow Flycatcher. These habitat details and score cards can be used to analyze current habitat conditions and potential for improvement.
What site conditions are associated with greater recovery and overall higher cover of willows? Goetz et al. performed a meta-analysis of tamarisk removal and willow (Salix) recovery across the southwest, compiling data from 260 sites where tamarisk was subject to active removal and/or biocontrol and 132 reference sures. Cut-stump method with biological control was the most effective method to improve native species dominance. Willow cover was generally highest in locations with low drought stress, as reflected by soil properties, distance to water, and climate.
A guide that walks the user through the use of the AGOL-based habitat viewer (https://usgs.maps.arcgis.com/apps/webappviewer/index.html?id=b362c94bd7714969805ab7dd29336ce0). User is provided with instructions for changing base map layers, toggling through data layers, utilizing tools to compare different datasets, and locating the metadata for the provided layers. Manual uses screen shots of the AGOL platform to aid in seamless navigation.