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With the advent of automated recording units, bioacoustic monitoring has become a popular tool for the collection of long-term data across extensive landscapes. Such methods involve two main components: hardware for audio data acquisition and software for analysis. In the acoustic monitoring of threatened species, a species-specific framework is often essential. Jerdon's courser Rhinoptilus bitorquatus is a Critically Endangered nocturnal bird endemic to a small region of the Eastern Ghats of India, last reported in 2008. Here we describe a reproducible and scalable acoustic detection framework for the species, comparing several commonly available hardware and detection methods and using existing software. We tested this protocol by collecting 24,349 h of data during 5 months. We analysed the data with two commercially available sound analysis programmes, following an analysis pipeline created for this species. Although we did not detect vocalizations of Jerdon's courser, this study provides a framework using a combination of hardware and software for future research that other conservation practitioners can implement. Vocal mimicry can aid or confound in detection and we highlight the potential role of mimicry in the detection of such threatened species. This species-specific acoustic detection framework can be scaled and tailored to monitor other species. [ABSTRACT FROM AUTHOR]

Birdsong is an important signal in mate attraction and territorial defence. Quantifying the complexity of these songs can shed light on individual fitness, sexual selection and behaviour. Several techniques have been used to quantify song complexity and be broadly categorized into measures of sequential variations and measures of diversity. However, these methods are unable to account for important acoustic features like the frequency bandwidth and the variety in the spectro‐temporal shape of notes which are an integral part of these vocal signals. This study proposes a new complexity method that considers intra‐song note variability and calculates a weighted index for birdsongs using spectral cross‐correlation.We first compared previously described methods to understand their advantages and limitations based on the factors that would affect the complexity of songs. We then developed a new method, Note Variability Index (NVI), which incorporates the spectral features of notes to quantify complexity. This method alleviates the need for manual classification of notes that can be error‐prone. We used spectrogram cross‐correlation to compare notes within a song and used the output values to quantify song complexity.To evaluate the efficacy of the new method, we generated synthetic songs to caricature extremes in song complexity and compared selected conventional complexity methods along with the NVI. We provide case‐specific limitations of these methods. Additionally, to examine the efficacy of this new method in real‐world scenarios, we used natural birdsongs from multiple species across the globe with varying song structures to compare conventional methods with NVI.To our knowledge, NVI is the only song complexity method that captures the variation of spectro‐temporal shapes of the notes in songs where the conventional methods fail to distinguish between similar song structures with different note types. Furthermore, as NVI does not need a manual classification of notes, it can be easily implemented for any type of birdsong with existing sound analysis software; it is quick, avoids the possible subjectivity in note classification and can be automated for large datasets. [ABSTRACT FROM AUTHOR]

Comparative population genomics is an ascendant field using genomic comparisons between species to draw inferences about forces regulating genetic variation. Comparative phylogeography, by contrast, focuses on the shared lineage histories of species codistributed geographically and is decidedly organismal in perspective. Comparative phylogeography is approximately 35 years old, and, by some metrics, is showing signs of reduced growth. Here, we contrast the goals and methods of comparative population genomics and comparative phylogeography and argue that comparative phylogeography offers an important perspective on evolutionary history that succeeds in integrating genomics with landscape evolution in ways that complement the suprageographic perspective of comparative population genomics. Focusing primarily on terrestrial vertebrates, we review the history of comparative phylogeography, its milestones and ongoing conceptual innovations, its increasingly global focus, and its status as a bridge between landscape genomics and the process of speciation. We also argue that, as a science with a strong "sense of place," comparative phylogeography offers abundant "place-based" educational opportunities with its focus on geography and natural history, as well as opportunities for collaboration with local communities and indigenous peoples. Although comparative phylogeography does not yet require whole-genome sequencing for many of its goals, we conclude that it nonetheless plays an important role in grounding our interpretation of genetic variation in the fundamentals of geography and Earth history. [ABSTRACT FROM AUTHOR]

Parasites, and the diseases they cause, are important from an ecological and evolutionary perspective because they can negatively affect host fitness and can regulate host populations. Consequently, conservation biology has long recognized the vital role that parasites can play in the process of species endangerment and recovery. However, we are only beginning to understand how deeply parasites are embedded in ecological systems, and there is a growing recognition of the important ways in which parasites affect ecosystem structure and function. Thus, there is an urgent need to revisit how parasites are viewed from a conservation perspective and broaden the role that disease ecology plays in conservation-related research and outcomes. This review broadly focusses on the role that disease ecology can play in biological conservation. Our review specifically emphasizes on how the integration of tools and analytical approaches associated with both disease and molecular ecology can be leveraged to aid conservation biology. Our review first concentrates on disease-mediated extinctions and wildlife epidemics. We then focus on elucidating how host–parasite interactions has improved our understanding of the eco-evolutionary dynamics affecting hosts at the individual, population, community and ecosystem scales. We believe that the role of parasites as drivers and indicators of ecosystem health is especially an exciting area of research that has the potential to fundamentally alter our view of parasites and their role in biological conservation. The review concludes with a broad overview of the current and potential applications of modern genomic tools in disease ecology to aid biological conservation. [ABSTRACT FROM AUTHOR]

Parasites, and the diseases they cause, are important from an ecological and evolutionary perspective because they can negatively affect host fitness and can regulate host populations. Consequently, conservation biology has long recognized the vital role that parasites can play in the process of species endangerment and recovery. However, we are only beginning to understand how deeply parasites are embedded in ecological systems, and there is a growing recognition of the important ways in which parasites affect ecosystem structure and function. Thus, there is an urgent need to revisit how parasites are viewed from a conservation perspective and broaden the role that disease ecology plays in conservation-related research and outcomes. This review broadly focusses on the role that disease ecology can play in biological conservation. Our review specifically emphasizes on how the integration of tools and analytical approaches associated with both disease and molecular ecology can be leveraged to aid conservation biology. Our review first concentrates on disease-mediated extinctions and wildlife epidemics. We then focus on elucidating how host–parasite interactions has improved our understanding of the eco-evolutionary dynamics affecting hosts at the individual, population, community and ecosystem scales. We believe that the role of parasites as drivers and indicators of ecosystem health is especially an exciting area of research that has the potential to fundamentally alter our view of parasites and their role in biological conservation. The review concludes with a broad overview of the current and potential applications of modern genomic tools in disease ecology to aid biological conservation. [ABSTRACT FROM AUTHOR]

Background: A long-standing view of Indian biodiversity is that while rich in species, there are few endemics or in-situ radiations within the subcontinent. One exception is the Western Ghats biodiversity hotspot, an isolated mountain range with many endemic species. Understanding the origins of the montane-restricted species is crucial to illuminate both taxonomic and environmental history. Results: With evidence from genetic, morphometric, song, and plumage data, we show that two songbird lineages endemic to the Western Ghats montane forest each have diversified into multiple distinct species. Historically labeled as single species of widespread Asian genera, these two lineages are highly divergent and do not group with the taxa in which they were previously classified but rather are distinct early divergences in larger Asian clades of flycatchers and babblers. Here we designated two new genera, the Western Ghats shortwings as Sholicola and the laughingthrushes as Montecincla, and evaluated species-limits to reflect distinct units by revising six previously named taxa and describing one novel species. Divergence dating showed that both these montane groups split from their Himalayan relatives during the Miocene, which is coincident with a shift towards arid conditions that fragmented the previously contiguous humid forest across peninsular India and isolated these lineages in the Western Ghats. Furthermore, these two genera showed congruent patterns of diversification across the Western Ghats Sky Islands, coincident with other climatic changes. Conclusion: Our study reveals the existence of two independent endemic radiations in the high montane Western Ghats or Shola Sky Islands with coincident divergence times, highlighting the role of climate in the diversification of these ancient lineages. The endemic and highly divergent nature of these previously unrecognized species underscores the dearth of knowledge about the biogeography of the Asian tropics, even for comparatively well-known groups such as birds. The substantial increase in the diversity of this region underscores the need for more rigorous systematic analysis to inform biodiversity studies and conservation efforts. [ABSTRACT FROM AUTHOR]

Montane grasslands in India face threats from habitat modification and climate change, but have received little conservation attention. In the Western Ghats, 55-80% of this habitat has been converted to commercial and non-commercial plantations. We examine the distribution of a range-restricted, grassland-endemic bird, the Nilgiri Pipit Anthus nilghiriensis through both fieldwork and literature survey. We combine our mist-net-based capture data with museum records that appear to indicate a smaller distributional range for the species than indicated by secondary sighting records. We argue that the species is limited to grasslands above 1900 m. Using GIS methodology, we estimate the area of this habitat to be only 441 sq. km. Spread over just two mountain-tops, our analyses indicate a drastic reduction from the presently projected distribution, making this species one of the most restricted-range birds in India. We discuss potential causes for this discrepancy, including misidentification, which may mislead potential conservation action for such threatened birds. We propose palaeoclimatic changes to be the cause for the present distribution limit to the two large mountains (Nilgiris hills and Anamalai-Palani hills), while anthropogenic habitat modifications may limit the distribution at a finer scale within these mountains. Given the combined effect of historical large-scale landscape modification in this region and the possibility of climate change affecting this species, the Nilgiri Pipit and its habitat appear to be under considerable threat and the bird requires urgent conservation measures, starting with an elevation of IUCN threat level to 'Endangered'. [ABSTRACT FROM AUTHOR]

The Shola habitat on the high elevation sky islands of the Western Ghats in southern India is a unique habitat. Although this habitat hosts a disproportionately high level of endemism and is threatened by anthropogenic modifications, it has received little research attention. We compiled publications of research conducted in this habitat from scientific databases and the grey literature to examine trends in publication. For a quantitative summary, all publications were classified according to the taxa of research and the broad topic of research. We identified 279 publications from 1964 and found an almost threefold increase in the number of publications and diversity of research topics studied over the last decade. Studies on flora, birds and mammals have been numerous (62% of the studies examined), but certain taxa like fish (1%) have been ignored. Most studies (65%) are descriptive, focusing on diversity, distribution trends and management suggestions, while surprisingly few have concentrated on climate change, ecological restoration and invasive species, all major threats to this landscape. We have identified some key gaps in research and conservation focus that future studies could address. We also suggest that initiatives like edited volumes and special journal sections, along with the use of creative commons licensed data-sharing portals, can be used to usher unpublished work into the public domain. [ABSTRACT FROM AUTHOR]