Elevational pattern and seasonality of avian diversity in Kaligandaki River Basin, central Himalaya

Abstract

This study explored bird diversity, seasonal variation, and associated factors along an elevational gradient in an important biodiversity area (IBA) of central Nepal: the Kaligandaki River basin of Annapurna Conservation Area. The field survey was carried out in 2019 over two seasons, winter (January and February) and summer (May and June) using the point count method. A total of 90 sampling plots were set up from elevations of 800m (Beni) to 3,800m (Muktinath). Data for variables including the number of fruiting trees (indicator of resource availability) and distance to the road (indicator of disturbance) were collected, and their influence on avian diversity were assessed. The results revealed a diverse assemblage of avian fauna in the study area with consistent species richness over the two seasons. A decline in species richness and diversity with increasing elevation was observed. Of the different habitat types within the study area, forest and shrubland habitats showed the strongest association with bird species distribution and richness. We emphasize the need for long-term monitoring programs with standardized sampling approaches to better understand the avifauna in the central Himalaya.

Bird diversity along an elevational gradient in Shivapuri Nagarjun National Park, Nepal

“…However, the number of bird species recorded in this study seemed low compared to the record of 318 species found in SNNP (BirdLife Nepal, 2018) which is the official checklist of birds that covers all sites of SNNP in all four seasons over a long period of time but our study was only limited in one trekking trail i.e., Sundarijal and only covers monsoon season. Insectivores were the most abundant species feeding guild in SNNP which is supported by many other studies on birds (Katuwal et al, 2016;Neupane, Khanal, Gyawali and Chalise, 2020;Pandey, Khanal, and Chalise, 2020). Bird Species belonging to Order Passeriformes were numerically most abundant in SNNP which is similar to study done by (Husein and Sultan, 2009) A similar pattern was also observed in other studies (McCain, 2009;Neupane et al, 2020;Rahbek, 1995;Santhakumar, Arun, Sony, Murugesan and Ramesh, 2018).…”

“…Insectivores were the most abundant species feeding guild in SNNP which is supported by many other studies on birds (Katuwal et al, 2016;Neupane, Khanal, Gyawali and Chalise, 2020;Pandey, Khanal, and Chalise, 2020). Bird Species belonging to Order Passeriformes were numerically most abundant in SNNP which is similar to study done by (Husein and Sultan, 2009) A similar pattern was also observed in other studies (McCain, 2009;Neupane et al, 2020;Rahbek, 1995;Santhakumar, Arun, Sony, Murugesan and Ramesh, 2018). This is due to significant decrease in plant species richness with increase in elevation along sub-tropical gradient in the Himalayas which had provided different habitats for various avian species (Bhattarai, Vetaas and Grytnes, 2004).…”

Forest Management Practice Influences Bird Diversity in the Mid-Hills of Nepal

“…Most studies in the Himalayan region show a hump-shaped pattern of bird richness, with the greatest diversity found at intermediate elevations [ 23 , 24 , 25 ]. However, a few studies in Nepal have also reported a monotonic decline of bird richness with increasing elevation [ 26 , 27 ]. As no studies have covered the entire elevational range of the Himalayas in Nepal, we recommend further studies that address the entire elevational gradients in the Nepalese Himalayas to generalize patterns of bird response towards elevation and other factors affecting their distribution.…”

“…However, the impact of management intervention on bird diversity and different feeding guilds (i.e., species exploiting resources in a similar manner) varies with topography (e.g., mountains versus plains), climate (e.g., tropical versus temperate areas), and seasonal changes [ 22 , 23 ]. Elevation gradient is another important factor in shaping bird assemblages in the Himalayas; most studies report hump-shaped patterns with the highest diversity at intermediate elevations [ 23 , 24 , 25 ], while some have found a monotonic decline with increasing elevation [ 26 , 27 ]. Few studies have examined the impact of forest management practice on bird community composition in South Asia, including Nepal (see [ 12 ]).…”

Urbanization Favors Some Over Others: Bird Diversity Pattern in the Suburban-Urban Gradient of Butwal City, Central Lowland of Nepal

“…It is pressurized by population surge and anthropogenic development increasing the intensity of urbanization. Most importantly, Butwal City lies along the northsouth migration route of trans-Himalayan birds along the Kaligandaki River Valley (Prins and Namgail, 2017;Neupane et al, 2020). Hence, it is important to know the bird species composition and effects of that rampant urbanization poses to the bird in Butwal City.…”