A unique aspect of montane birds is the elevational stratification they show in their distribution, but in the Himalayas, a subset of the species show elevational migration, making bird communities on these mountains especially dynamic. Thus, understanding the elevational distribution and movement of species across seasons is important to fully understand broad-scale community patterns. In this study, we compile a comprehensive checklist of birds along a 2,300 m Hima­layan elevational gradient in the Amrutganga Valley, Kedarnath Wildlife Division, Uttarakhand, India. We recorded 244 species including 34 species new for the area and two new species for the state. Most importantly, we describe the elevational distribution of more than a 200 species and the dates of first sighting for several summer migrants in the season. We also studied changes in species richness and turnover at multiple elevations across seasons. We hope that this study provides a baseline for future research on elevational distribution of birds in the Western Himalayas.

Context Tropical montane habitats support high biodiversity and are hotspots of endemism, with grasslands being integral components of many such landscapes. The montane grasslands of the Western Ghats have seen extensive land‐use change over anthropogenic timescales. The factors influencing the ability of grassland‐dependent species to persist in habitats experiencing loss and fragmentation, particularly in montane grasslands, are poorly known. Objectives We studied the relationship between the Nilgiri pipit Anthus nilghiriensis , a threatened endemic bird that typifies these montane grasslands, and its habitat, across most of its global distribution. We examined what habitat features make remnant grasslands viable, which is necessary for their effective management. Methods We conducted 663 surveys in 170 sites and used both single‐season occupancy modeling and N ‐mixture modeling to account for processes influencing detection, presence, and abundance. Results Elevation had a positive influence on species presence, patch size had a moderate positive influence, and patch isolation had a moderate negative influence. Species abundance was positively influenced by elevation and characteristics related to habitat structure, and negatively influenced by the presence of invasive woody vegetation. Conclusions The strong effect of elevation on the highly range‐restricted Nilgiri pipit is likely to make it vulnerable to climate change. This highly range‐restricted species is locally extinct at several locations, and persists at low densities in remnants of its habitat left by recent fragmentation. Our findings indicate a need to control and reverse the spread of exotic woody invasives to preserve the grasslands themselves and the specialist species dependent upon them.

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.

Drought is a natural phenomenon which differs from other natural hazards by its slow accumulating process and its indefinite commencement and termination. The present study addresses water deficiency and drought occurrence over Kutch district, Gujarat, because nearly 45% of the whole Kutch district is severely suffering by deficiency of water. Earth observation data (LANDSAT ETM+) and Standardized Precipitation Index were used to analyze drought severity. Daily rainfall data over the study area were obtained from Indian Meteorological Department (IMD) for the period of study and geo-referenced for further analyses. Using Remote Sensing and GIS techniques, rainfall variability map over the period of study has been prepared to show rainfall distribution and land use and land cover map is prepared to show the area under different land use classes and impacts of drought over land uses. Standardized Precipitation Index (SPI) was generated for each block wise and scenario of drought development has been analyzed using decadal data set for the study period . The present study suggests method and techniques for continuous drought monitoring by linking temporal earth observation and rainfall data. The methodology will be very useful for the development of a regional drought monitoring system.

1. 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.2. 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.3. 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. 4. 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.

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Despite its prevalence across bird taxa, avian vocal mimicry remains a poorly studied field of animal behaviour. In order to advance our understanding of the function of avian vocal mimicry, the field requires that the range of vocal mimicry in birds is described. The Tawny Lark (or Sykes's Lark, Galerida deva) is endemic to central and western India. Recent work on other Galerida larks has found that the mimetic vocalisations match the biodiversity of their acoustic environment, thereby conferring a significant novel function in study of individual mimetic variation linked to biodiversity. Here, we provide a detailed account of the variety of mimetic sounds produced by the Tawny Lark. We also describe acoustic and peer-based analyses that gauge the accuracy of the mimicry. By providing a detailed description of mimicry, we provide a basis for future study of the function of mimicry in this species.

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