What’s the news?

• The State of the World’s Birds, an annual review of environmental resources published by nine natural sciences and avian specialists across the globe, has revealed that the population of 48% of the 10,994 surviving species of birds is declining.
• The report led by the Manchester Metropolitan University gives an overview of the changes in the knowledge of avian biodiversity and the extent to which it is imperilled.

Key Findings 

• The study found that 5,245 or about 48% of the existing bird species worldwide are known or suspected to be undergoing population declines.
• While 4,295 or 39% of the species have stable trends, about 7% or 778 species have increasing population trends. The trend of 37 species was unknown.
• The study draws from BirdLife International’s latest assessment of all birds for the IUCN’s Red List that shows 1,481 or 13.5% species are currently threatened with global extinction.These include 798 species classified as vulnerable, 460 as endangered and 223 as critically endangered while 52 species were considered to be data deficient.
• The more threatened bird species (86.4%) are found in tropical climates than in temperate latitudes (31.7%), with hotspots for threatened species concentrated in the tropical Andes, southeast Brazil, eastern Himalayas, eastern Madagascar, and Southeast Asian islands.

What is the importance of birds to Ecosystems and Culture?

• Birds contribute toward many ecosystem services that either directly or indirectly benefit humanity. These include provisioning, regulating, cultural, and supporting services.
• The functional role of birds within ecosystems as pollinators, seed-dispersers, ecosystem engineers, scavengers and predators not only facilitate accrual and maintenance of biodiversity but also support human endeavors such as sustainable agriculture via pest control besides aiding other animals to multiply.
• Wild birds and products derived from them are also economically important as food (meat, eggs). Approximately 45% of all extant bird species are used in some way by people, primarily as pets (37%) and for food (14%).
• Beyond its symbolic and artistic values, birdwatching is a global pastime practiced by millions of people. Garden bird-feeding is valued at $5-6 billion per year and growing by 4% annually.

What are the threats contributing to avian Biodiversity Loss?

• The study lists eight factors, topped by land cover and land-use change.
•  The continued growth of human populations and of per capita rates of consumption lead directly to conversion and degradation of primary natural habitats and consequent loss of biodiversity.
• Although global tree cover increased between 1982 and 2016, including by 95,000 sq. km in the tropical dry forest biome and by 84,000 sq. km in the tropical moist deciduous forest biome, this has been driven by afforestation with plantations (often of non-native species) plus land abandonment in parts of the global North, with net loss in the tropics.
• The other factors are habitat fragmentation and degradation, especially in the tropics; hunting and trapping with 11 to 36 million birds estimated to be killed or taken illegally in the Mediterranean region alone; the impact of invasive alien species and disease (971 alien bird species introduced accidentally or deliberately to 230 countries over the centuries have affected the native species); infrastructure, energy demands and pollution; agrochemical and pharmaceutical usage (pesticide ingestion kills an estimated 2.7 million birds annually in Canada alone); global trade teleconnections; and climate change.

Can the Avian Biodiversity Loss be stemmed?

• The study says ornithologists have a good understanding of the spatio-temporal patterns of avian diversity to take measures needed to slow down avian biodiversity loss.
• The growing footprint of the human population represents the ultimate driver of most threats to avian biodiversity, so the success of solutions will depend on the degree to which they account for the social context in which they are implemented, and our ability to effect changes in individual and societal attitudes and behaviors. 
• Emerging concepts of conservation social science can inform efforts to address biodiversity loss and to achieve more effective and sustainable conservation outcomes, linking birds to human well-being, sustainability, climate resilience, and environmental justice.

Reference:

1. https://www.thehindu.com/sci-tech/energy-and-environment/the-grim-forewarnings-of-a-global-study-on-birds/article65401614.ece