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Open Natural Ecosystems (ONEs), such as tropical grasslands, are among the most threatened habitats on Earth today. The long-term monitoring of ONEs is an important research domain that is essential for understanding anthropogenic impacts and facilitating conservation action. Using a simple day-listing method over a 12-year period, we studied bird abundance in a central Indian grassland-agriculture mosaic experiencing several land-use changes. Our results indicate that some grassland species (such as the Great Indian BustardArdeotis nigriceps) show steep declines during the study period, while woodland species (such as the Small MinivetPericrocotus cinnamomeus) show highly fluctuating populations with no discernable trend. Daily listing also reveals distinct seasonal patterns, and we discuss the Great Indian Bustard and Eurasian Marsh HarrierCircus aeruginosusas examples. Our study highlights the utility of consistent checklist surveys to monitor abundance trends of bird communities within a changing landscape.

Woodpeckers (family Picidae) are a specialised group of insectivores that are sensitive to forest degradation and fragmentation. We evaluated the woodpecker taxa as potential indicators of habitat quality and forest bird diversity in temperate moist hardwood forests (1500–2400 m asl), a threatened biome in the Western Himalaya. 74 forest sites, selected to represent a gradient of anthropogenic use, were surveyed for birds, vegetation structure and proportion of land under dense forest in the surrounding landscape. Individual woodpecker species were observed to quantify their foraging niche preferences. We found that forest sites with higher woodpecker richness were also rich in all other bird species. Further, the richness and abundance of woodpeckers and all other birds were affected by similar habitat variables. Four out of the eight woodpecker species occurring in the study area were found to fit our habitat models suitably, with canopy cover, tree density, and forest proportion proving to be important variables. Behavioural observations showed that the same four woodpecker species significantly preferred larger and taller trees for foraging. Given the difficulty of directly monitoring forest characteristics and total bird diversity over large landscapes, consistent monitoring of sensitive woodpecker species can provide answers to both. Further, as woodpeckers are moderately common and conspicuous birds, areas with high woodpecker diversity can be easily identified and prioritised for conservation.

Rural populations in developing countries depend on forests for fuelwood, fodder and other non-timber forest products. Such dependence has significant effects on faunal diversity and composition, primarily due to alteration of vegetation structure. While earlier studies have assessed the consequences of extractive activities for forest fauna, very few simultaneously acknowledge the role of landscape context, which includes agricultural land-uses and managed forests. This study was carried out in oak-dominated forests located in the middle elevations of the Western Himalayas to investigate effects of extractive activities on avifaunal communities, taking into account the role of landscape composition. Birds were sampled at 74 sites, six times each, over two seasons using fixed-radius point counts. We analysed avian species richness, abundance, composition and guild abundances (based on foraging and habitat preference) as a function of vegetation structure and proportion of dense oak forest around each site. Our results suggest that extractive activities in forests can result in reduced species richness, abundance and altered composition of forest avifauna, brought about by changes in vegetation structure. We also find that these effects may be intensified by the loss of dense oak forests in the landscape. Insectivorous birds and forest specialists were most sensitive to extractive activities and landscape composition. Decreasing canopy cover and proportion of oak forest in the landscape had strong negative effects on insectivorous and forest specialist species. Other local factors such as vertical stratification and understory density also had effects on these avian guilds. Our study indicates that in order to conserve bird species in an increasingly human-dominated landscape of the Western Himalayas, it may be necessary to control extractive activities that affect forest structure as well as retain protected forest stands within a continuum of harvested forest and agricultural landscapes.

Oak species worldwide are experiencing declines, with negative consequences for hardwood forests and their associated biodiversity, but the causes of these declines vary across species and habitats. We examine changes in extent of banj oak-dominated (Quercus leucotrichophora) moist temperate hardwood forests in a Western Himalayan landscape between 1991 and 2017. Using classified satellite imagery from 1991, 2001 and 2017, we found that dense banj oak forests have undergone substantial degradation and loss of area, while chir pine (Pinus roxburghii) forests have expanded, largely by replacing degraded banj oak stands. This transition was most likely to occur at sites that had lower levels of winter precipitation and Topographic Wetness Index (TWI) values and more pine forest in the surrounding landscape. Our findings are consistent with known requirements of shade and moisture for the recruitment of banj oak. Loss of banj oak forests is likely to reduce biodiversity and a number of ecosystem services linked to the well-being of local communities.

Land use change is the most widespread driver of biodiversity loss in densely populated tropical countries. Biodiversity loss, in turn, results in changes in functional guilds responsible for various forest ecosystem services. It is thus necessary to understand the extent and types of biodiversity loss and functional guild alteration caused by land use change in order to facilitate sustainable land use policies. Here we study the effects of land use change on forest bird species and guilds in a human-dominated landscape in the Western Himalaya, India. We carried out systematic breeding-season surveys in six land use types within moist temperate forest: natural (protected) oak forest, degraded (lightly used) oak forest, lopped (heavily used) oak forest, pine forest, cultivation and built-up sites, in two adjoining landscapes, over two consecutive years. Our study shows moderate to drastic species loss in all modified land use types in comparison to natural oak forest. Species composition in modified land use types diverged significantly from natural oak; this effect was highest in cultivation and built-up sites and least in degraded forests. Compositional change in modified land uses occurred due to partial replacement of forest specialists with commensals and open country species, whereas abundance of forest generalists was relatively constant across the gradient. We also find a steep decline in the abundance of functional guilds such as pollinators, and insectivorous pest controllers in all modified land uses in comparison to natural oak forest. Our results have important implications for conservation in biodiverse mountain landscapes with significant human imprint. In particular, (a) low faunal diversity in monocultures and urban sites (b) drastic (50% loss or more) loss of forest specialists, pollinators and insectivores in degraded forests, monocultures and urbanised sites; and (c) the potential for degraded forest as refugia for forest species, are findings that can be globally applied to land use and conservation planning in human-dominated landscapes.