In bird flight patterns, signs of looming disaster

A warming world is changing bird life for sure. Especially during the migration of bird species from the colder northern latitudes to the warmer tropics for food and shelter. In a global melting pot, as genes (with coded adaptive messages) are passed from one generation to the next, some bird populations may not wish to undertake the arduous journeys when food is available throughout the year. While the phenomenon of bird migration will not cease to exist anytime soon, we are getting more and more reports of birds staying back either in their summer breeding habitats or vice versa – in their winter homes or somewhere in between. For example, if you happen to go for a walk along the Yamuna, the Okhla Bird Sanctuary in Delhi, a few long-distance avian visitors from the Arctic region, Ruffs, Wood Sandpipers, Green Shanks, Little and Temminck’s Stints are still lingering way beyond from their usual time of departure. And we don’t know why!

May 11 is observed all over as World Migratory Bird Day, a day when the spotlight is on the protection of migratory birds and their habitats. This year, the campaign has an added focus on the state of insect populations--food for migratory birds – declining due to excessive pesticide usage and light pollution.

Taej Mundkur, senior advisor, Wetlands International, says that a population of the migratory Bar-headed goose, one of the highest-flying migratory birds, is not flying further north to their breeding grounds in Mongolia. The freezing conditions over the Tibetan plateau have transformed to more warmer climes giving way to agricultural expansion and unlocking food in plenty for the foraging geese to settle down. Long-term research states that while four of China’s six wintering populations of “grey” geese declined during the last decade, the wintering population of Bar-headed geese in the Tibet Autonomous Region has more than doubled. Similar narratives of geese not flying further north also come from the border regions of Afghanistan, Turkmenistan and Uzbekistan.

Birds are wired to migrate with food and nesting resources on their radar. Now with these examples, there is a clear trend pointing to a timing mismatch between migrants and their food sources. And these may be the reasons behind contracting or expanding bird populations. Specialist feeders are declining while generalists with a greater ability to adapt are expanding on a planet in flux. A classic local example is the Bank myna (the name comes from river bank), which has moved to colonise toll plazas and railway stations as its natural habitat flood plains are taken up for development. The toll plazas provide easy pickings, food grains from goods trucks and trains.

Long-term data from years of bird banding and satellite telemetry, traditional and modern tools to track birds, have helped ornithologists demarcate bird flyways on the globe and how different bird populations migrate seasonally from North to South. There are nine such flyways, scientific models for the conservation of bird species and their habitats. The Indian subcontinent sits at the base of the Central Asian Flyway (CAF), wintering home to populations of 600 plus species of migratory birds. Amongst these, 240 species of migratory birds are in decline. There are also gains like the case of the Bar-headed goose mentioned here.

While the Indian landmass offers diverse habitats for migratory birds, all are rapidly on the decline, due to our insatiable “developmental” needs. Increasing temperatures with extreme weather events are said to accelerate the further disappearance of bird habitats. Like the Bank myna or the Bar-headed goose, how others will take to newer conditions is still to be seen.

The State of Indian Birds (2023) report mentions 217 species are stable or have increased in the last eight years and 204 species are in decline in the past three decades. The report says that birds of open ecosystems, rivers, and coasts have declined the most. But as migration patterns change there is a need to expand and redesign population estimation models.

In February, at the 14th meeting of the Conference of the Parties to the Convention on the Conservation of Migratory Species (COP14/CMS) in Samarkand, Uzbekistan, it was agreed that India will host a coordinating office to act as a platform for capacity building, knowledge sharing, research and coordination with all 30 range countries. The ministry of environment, forest and climate change is the implementing agency and may be working on a plan but time is of the essence with extreme weather on top of the global risk for 2024 and the ominous news of the Indian Ocean moving towards a state of near-permanent marine heatwaves.

Extremely high April temperatures over eastern and peninsular India reflect the severity of the climate crisis. At the same time, the Supreme Court has stated that everyone has “the fundamental right to be free from the adverse effects of climate change”. The Court also highlighted the critical role of forests in mitigating the climate crisis, citing forests as a national asset linked to India’s financial security. It referred to the Reserve Bank of India report, “Macroeconomic Impact Of Climate Change In India (2023)”, which stated, “Climate change manifested through rising temperature and changing patterns of monsoon rainfall in India could cost the economy 2.8% of its GDP and depress the living standards of nearly half of its population by 2050.” These two recent judgments within a month clearly raise concerns over the state of the environment.

But is the climate alarm and what’s to be done about it for our survival alone? Definitely not. We are intrinsically linked to the fate of a vast diverse set of species sharing the human-altered world, fighting for survival and keeping the natural environment running through their complex ecological roles. We owe it to them as much as to ourselves.

Ananda Banerjee is an author, artist and wildlife conservationist. The views expressed are personal