Dinesh Bhatt

The scientific study of acoustic signals and their ecological functions in birds is termed avian bioacoustics. This field has gained significant attention worldwide, as evident from the large volume of relevant research publications. However, despite the presence of more than 1,300 avian species in India, limited studies appear in this field. Moreover, the research made so far on bird models in India seems scattered and relatively underrepresented in the global literature. This review addresses this issue by compiling the studies dealing with acoustic communication in birds in India, with a focus on research trends, methodologies, and key discoveries made so far. Publications on the neural mechanisms of song production and automated species recognition or machine-learning classification in avian bioacoustics are not included in this review.

The population boom increases land-use requirements, and shrinking regions are available to preserve natural biodiversity. Unfortunately, scientific knowledge does not seem to have and might never get a correct solution to how much territory will be sufficient for satisfying the various biodiversity conservation goals. Prioritization of habitat, primarily for threatened species, is a critical management challenge. Habitat management efforts are gradually being performed over broader geographic regions, emphasizing the necessity of spatial and strategic prioritization. Habitat prioritization is a technique popular for identifying critical areas needing conservation initiatives. To develop a strategic conservation framework, key issues must be identified based on the ground knowledge and present land use status, which are difficult to gather for highly rough terrain areas. Incorporating spatial data sets thus helps to get the desired knowledge of the site on a large scale. This study used a grid-based multicriteria approach to create a spatial conservation management framework for the Rajaji-Corbett landscape (RCL) in Northern India. A grid-based prioritization assessment was conducted to identify priority areas for the RCL, keeping invasive species and fire as significant threats. The indicators or criteria were selected by looking at present vital concerns in the landscape. We took 20 indicators for our multicriteria assessment for landscape prioritization of RCL using 2 × 2 km grids for the evaluation and classified them according to low, medium, and high priority areas using Arc GIS Pro. The results identified 931 sq. km area of this landscape needs immediate management interventions where frequent fire incidents and presence of invasive species are high. RCL is well known for its biodiversity wealth and assemblage of various wildlife populations.

This paper aims to study the structure and pattern of dawn song in a tropical avian species, the Pied Bush Chat (Saxicola caprata) in Haridwar (290 55’ N, 780 08’ E; Uttarakhand, India) in 2009. Males delivered complex dawn chorus on daily basis during only breeding season (February to July). The dawn song bout was made up of a number of distinct sections called song types. Each song type consisted of a series of similar or dissimilar units referred to as elements. Song type length averaged 1.43±0.23 sec and did not differ significantly among males. Theaverage number and types of elements in a song type were observed 8.15±1.64 and 8.01±1.56, respectively.In more than 80% of observations, song types were delivered with immediate variety and males did not follow any definite sequential pattern of song delivery. Males sang continuously for about 30 min at high rates during dawn. Males performed continuous dawn singing throughout the breeding season and seemed to interact vocally through counter-singing for extended period. Observations suggest that dawn song delivery in Pied Bush Chat plays an important role in maintenance and adjustment of social relationship among neighbouring males.

The Indian subcontinent is amongst the biologically better known parts of the tropics and its bird fauna has been well documented. However, avian community composition and diversity along elevational gradients and amongst habitat types remains unclear in India. We attempted to estimate bird assemblages in terms of diversity, species composition, status and abundance in urban and forest habitats of Nainital district of Uttarakhand (350–2450 m asl; 29°N), Western Himalayas. We sampled different elevational gradients and to understand the effect of urbanization and season on avian community composition. Field studies were conducted during January 2005 to January 2007. Results indicated that the forest had more complex bird community structure in terms of higher species richness (14.35 vs 8.69), higher species diversity (Shannon’s index 4.00 vs 3.54), higher evenness (0.838 vs 0.811) and more rare species (17 vs 5) as compared to urban habitat. However, the abundance of 11 species was higher in urban habitats. Bird Species Richness (BSR) varied considerably among study areas (91 to 113 species), was highest (113 species) at mid elevation (1450–1700 m asl) and decreased (22 species) at high elevation (1900–2450 m asl). It seems that high BSR at mid altitudes is not caused by the presence of a group of mid altitude specialists but rather that there is an overlap in the distribution of low land and high elevation specialists at this altitude. BSR and Bird Species Diversity fluctuated across seasons but not habitat type.