“Avian diversity peaks globally in the tropics and it is there that we also find the highest richness of threatened species,” Alexander Lees, Senior Lecturer at Manchester Metropolitan University, and lead author of the study, said. “We know a lot less about the fortunes of tropical bird species than we do about temperate ones, but we are now witnessing the first signs of a new wave of extinctions of continentally-distributed bird species which has followed the historic loss of species on islands like the Dodo.”

The study involved scientists from Manchester Metropolitan University, Cornell University, Birdlife International, the University of Johannesburg, Pontifical Xavierian University and Nature Conservation Foundation, India. It found deterioration in the conservation status of the majority of bird populations at temperate latitudes, with threatened species were mostly concentrated in the tropics, which host the richest avian diversity.

The story of decline in India

In case of India, the report found, that the decline in bird populations was higher than the global average with around 50% of the populations falling strongly. The report said in case of forests, the decline was 60%, in wetlands 55% and in grasslands 50%. However, in north America and Europe, the bird population has remained the same or has witnessed marginal decline due to improvement in habitats and wetlands, the report said.

“Bucking these negative trends have been many wetland bird species in North America and Europe, where wetlands have experienced a net gain in bird abundance of 13% since 1970 (based on summing abundance estimates across species). This has been driven by a 56% increase in waterfowl populations in this period, associated with wetland restoration and management for hunting. In Europe, there have been similar increases, especially associated with thermally sensitive warm-dwelling species,” the report said.

The study said, with “sufficient confidence for 146 species” in India, that nearly 80% were found to be declining (50% of these declining strongly), while just over 6% had stable population trajectories, and 14% of species exhibited increasing population trends.

And the reason for the decline is the land-use change, especially in the wetlands and forested areas, where rampant mining and construction activity has been allowed in the past 30 years or so, the period of the decline identified.

The study has pointed out that the loss of habitat in Northeast and some other Himalayan regions as a reason for decline in bird population in India. It also said that for some species such as the Great Indian bustard, power lines represent the most significant threat. The GIB is found in western Rajasthan and Kutch region of Gujarat and the Supreme Court is hearing a petition to protect the bird species from the threat power lines and wind mills cause to them. The Supreme Court had sought an action plan to save them from Gujarat and Rajasthan governments.

Global trends

At a global scale, at least 50% of forest-dependent birds in South Africa are experiencing range declines, avian abundance in Costa Rica has declined over 12 years and abundance of forest interior species in one South America has declined over 35 years. BirdLife International’s latest assessment of all birds showed that 1,481 species (13.5% of 10,994 recognized extant species) are currently threatened with global extinction.

More threatened bird species are found in tropical than in temperate latitudes with hotspots for threatened species concentrated in the tropical Andes, southeast Brazil, the eastern Himalayas, eastern Madagascar, and Southeast Asian islands. All countries and territories host at least one globally threatened bird species, and ten have more than 75, with Brazil and Indonesia heading the list at 171 and 175, respectively, the study said, adding that 55% of threatened species are endemic to single countries or territories.

Seventy species have improved in status sufficiently to qualify for lower categories of extinction risk since 1988, almost entirely owing to successful conservation actions, the report said. However, 391 species that have deteriorated in status sufficient to qualify for higher categories of extinction risk during this period, resulting in an overall decline in the Red List Index of International Union for Conservation of Nature (IUCN). The decline in population is expected to continue with contemporary economic growth, consumption patterns, and energy mix.

The threats

Although the decline in the bird populations may not be uniform across the world, the reason for it is.

According to the report, the degradation of the wildlife habitats and loss of bio-diversity because of human consumption is the biggest reason for birds losing their homes. “Land-cover changes driven by human activities have been occurring for millennia and are likely to have reduced total bird abundance by between a fifth and a quarter since pre-agricultural times,” the report said. It added that 20th and 21th century habitat loss was imperiling more species with close to 1,370 species directly impacted by land use changes.

The report identified biosphere changes as a reason for threat to 2,250 species, agriculture practices to 2,100 species, climate to 1,100 species, invasive species to 1,000 species and natural system modifications to another 800. Pollution, the study said, impacted around 500 species and human interference about 400.

However, the report said that the climate crisis was emerging as a driver for change in bird communities and is a particular concern for tropical montane, polar, and migratory species.

However, in places, where the site based conservation has improved, the survival rate for 76% of the threatened bird species has gone up. There are close to 13,000 important bird and biodiversity areas identified for threatened species across the globe covering 6.7% of land and 1.6% of oceans (totaling 3.7% of earth’s surface area). Of these 127 biodiversity areas have been identified as Alliance for Zero Extinction sites as they hold the last remaining population of one or more of the 185 Critically Endangered or Endangered bird species, the report said.

However, in India, most of the biodiversity rich areas are not in best of green health. India has lost about 1.5 lakh hectares of forest land between 2000 and 2020 for developmental projects such as mining and hydro power in the best bird habitats like the ones in Western Ghats, Hasdeo Arand in Chhattisgarh and north-east India. Between 2015 and 2020, the government allowed diversion of about 55,000 hectares to projects, according to a statement made in Parliament in March 2022. About 30% of wetlands have been lost in India in the past 30 years due to illegal construction, unsustainable urbanisation, agriculture expansion and pollution, as per estimates of Wetland International South Asia released on 13 August 2021.

Protecting bird homes

The Convention on Biological Diversity (CBD) has proposed conserving 30% of land, sea and freshwater ecosystems for threatened bird species and wildlife. However, at a recent meeting of all signatories to the convention there was no consensus on the draft to achieve the goal. The Wildlife Conservation Society in a statement slammed the countries for lack of “ambition” to combat the biodiversity crisis that harms all.

“Biodiversity is in crisis, ecosystems are collapsing, and, without further action, we could experience another pandemic of zoonotic origin, and we call on all governments to exercise more political will, leave narrow interests at home, and come together between now and Kunming (China) to adopt a strong, ambitious, meaningful GBF (Global Biodiversity Framework)—for the sake of our planet, and all of humanity,” said Susan Lieberman, WCS Vice President of International Policy. The countries would be meeting again in second part of 2022 to discuss the framework that provides for 20-point charter to protect biodiversity.

The report clearly shows that the birds are losing their homes because of excessive developmental activity and encroachments, especially on the water bodies. If the trend is not reversed quickly, many birds, who provide several ecological services to humans, will go extinct, creating an imbalance in nature, which would be difficult to fill. Humans need to save bird habitats for themselves, not birds.

The views expressed are personal