Declining forest bird species in Western Himalaya

Context:

With extremely cold winters and pleasant summers, the State of Uttarakhand is home to the Western Himalayan temperate forests which harbour a large number of endemic bird species.

A new study that analysed these natural oak-dominated forests and modified forests has noted that there was a drastic loss of bird species in all modified landscapes.

Relevance:

GS-III: Environment and Ecology (Conservation of Ecology and Biodiversity)

Dimensions of the Article:

1. About Himalayan Biodiversity
2. Highlights of the study on Declining Forest bird species in Himalayas
3. Threats faced by Himalayan Biodiversity

About Himalayan Biodiversity

• Himalayas form about 12% of the country’s landmass and is home to about 30.16% of its fauna and 31.6% of its flora.
• In, India, Himalayas is spread over six states – Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Sikkim, West Bengal and Arunachal Pradesh.
• The Himalayas are divided into two bio-geographic zones namely – Trans-Himalayas and Himalayas based on the physiographic, climatic and eco-biological attributes.
• Himalayas is endowed with a varied biodiversity from alluvial grasslands to subtropical broadleaf forest, mixed conifers and conifer forests in higher hills and alpine meadows above the tree line.
• Himalayas has high species diversity and endemism and is one of the hotspots located in India.
• Himalayas has over 131 protected areas which include 20 national parks, 71 wildlife sanctuaries, five tiger reserves, four biosphere reserves and 7 Ramsar Sites.

Highlights of the study on Declining Forest bird species in Himalayas

• Six major land-use types which included natural oak forest, degraded oak forest (lightly used), lopped oak forest (intensively used), pine forest, agricultural cultivation area and sites with buildings were studied.
• The results showed that there was a low diversity of species in monoculture areas and urban sites.
• They also noted a drastic loss of pollinator birds and insectivores in the degraded forests, monocultures and urbanised sites.
• The study also noticed strong decline in some of the habitat guilds in the areas that experienced land-use change. – Habitat guilds are groups of bird species that have common habitat preferences.
• The researchers noticed that many of the species that dropped out of the modified land areas were recognised oak forest specialists such as rufous-bellied woodpecker, greater yellownape, rufous sibia, white-throated laughingthrush and black-faced warbler.

Woodpeckers and Positive observations

• The study found that the higher the number of woodpeckers at a site, the higher was the richness of all other birds. The cavities that woodpeckers make on trees are used by a number of other birds to nest in.
• They also noted that two species (rufous-bellied woodpecker and greater yellownape) showed great potential as indicators of forest quality as they were most likely to be found in dense canopied forests with larger and taller trees on which they preferred to forage.

Threats faced by Himalayan Biodiversity

1. Climate Change and Global Warming – It is one of the biggest threat faced by many threatened species of vertebrates and mammals and is evident from the shifting distribution of certain species such as Asiatic Black Bear, Snow Leopard etc.
2. Poaching – Illegal trade in some of the flagship species such as snow leopard, tigers etc. Has led to uncontrollable poaching and killing of wild animals for trade.
3. Human – Animal Conflict – The retaliatory killing by the farmers and villagers is also a major threat.
4. Habitat loss and Receding glaciers due to climate change – Climate change has many associated impact on an ecosystem which leads to changed precipitation pattern and change in mean temperature. This results in loss of endemic plants species and loss of glaciers in the Himalayas.
5. Unregulated harvesting of Himalayan Herbs – Some of the Himalayan herbs have medicinal qualities such as Himalayan trillium, due to which they are extensively harvested combined with grazing of cattle leads to their vulnerability and possible extinction.
6. Alien Species – Alien species are a threat to endemic species because they grow unchecked and do not have natural predators such as lantana camara.
7. Natural threats – Threats such as landslides and shifting river course also impact the natural vegetation and faunal diversity.
8. Encroachment – There is increasing population pressure seen in terms of extension of agricultural land, exploitation of forests for timber, fodder and fuel wood, intensive grazing. These are the major factors contributing to the habitat loss of various flora and fauna.
9. Infrastructure Development – The competition to develop economy, increasing urbanisation, attaining energy security, connecting remote areas intrudes massively in the natural ecosystem of the Himalayan region.
10. Waste Disposal – Human populations, their habitat, discharge from the industries in Himalayan regions give rise to unimaginable non-biodegradable wastes and toxics. These foreign substances enter in the local food chain and through bioaccumulation and biomagnifications completely alter the natural ecosystems.
11. Political reasons – Insurgencies, wars, military operations and presence of war zone along India’s Pakistan and China Border cause destruction of forests and the biodiversity.
12. Ceasing the conservation effort – Down listing the species from ‘endangered’ to only ‘vulnerable’ signals that the species does not require the same amount of attention and resources as before

-Source: The Hindu