The social media is erupting with news about how North America has lost 3 billion birds in 50 years. People definitely seem to be alarmed by the news. Nepal and Asia are losing birds at an alarming rate too, due mostly to anthropogenic causes, climate change, habitat destruction and trade. Birds need a place to nest, they’re either cavity nesters or open nesters. Habitat encroachment is affecting every single one of them. There are reports of a decrease in population of the species I work with, Passer domesticus, commonly known as the house sparrow.

House sparrows are secondary cavity nesters, meaning that they make nests in pre-existing cavities and spaces. They don’t build nests in trees. In traditional brick houses, the small holes left in the walls are often occupied by house sparrows. In recent years, as we’ve gone concrete and stopped leaving those gaps, it’s obvious that we don’t see house sparrows around. You will see house sparrows, pigeons and crows around human settlements, also swallows if there are agricultural fields nearby. In the countryside, you hear the melody of song birds.

Long-distance fliers

I remember going to Taudaha in 2008 during the migrating season, and it was different, it was natural, and there were tonnes of birds. When I went there last year, the size of the lake was considerably smaller with concrete structures encroaching on the water. The wetland had become more a place of recreation for humans than a stop for migratory birds that had flown thousands of kilometres to get there.

I was in Taudaha to see bar-headed geese. They fly above Everest to reach their breeding grounds in Nepal and India. Above Everest! Only to find humans occupying their habitat and encroaching upon it every year. One of the elderly citizens who owned a tea shop near the lake told me that there were fewer birds now. I wasn’t surprised. Taudaha was a barren land with no resources for water birds. We should be focusing on how to enrich the resources that can help the birds, instead of opening shops and restaurants, and playing loud music all around.

Taking about sound pollution, let’s talk about how noise affects birds. There can be a wide array of effect on birds from loud noises—from damaging the ears to increasing stress response or changes in foraging or call responses or even flight-fight response. One of the most important is the communication part. Birds rely on communication for many things, especially breeding. Various studies have shown that due to anthropogenic noise pollution, birds are forced to change their call frequency or amplitude. But it’s a two-way street, and the noise can dampen their ability to sense predatory attacks. Either way, the bird population is diminishing because of us.

Whether it's migratory birds or resident birds, their numbers are declining at an alarming rate. Birds are an integral part of our ecosystem. And with all the changes that we’re responsible for, we are only accelerating the rate of loss. We’re losing vultures every day at an alarming rate, all because of the use of the anti-inflammatory drug diclofenac in cattle. Vultures eat dead cattle and ingest the drug which is toxic to them. But extinction and population control is a natural phenomenon, animals have been going through the constraints of nature since they evolved. They adapt if they can; and if they can’t, they die and don’t get to reproduce. Over a long period of time, those who can adapt get to live, and those who can’t die.

But the problem is we are changing things so fast they don’t get a chance to adapt to the changes. Climate change is a force that’s definitely spurring this trend. The irregular warm and cold cycles affect the birds breeding and migrating habits as well. They depend on nature’s cues for such activities. Imagine reaching a breeding ground earlier than they’re supposed to because the temperature was all off. That’ll definitely affect their morphology as well as survivability.

How we can help

I think it would be better if we could act on it sooner than later. Leaving a small cavity in the wall of your multi-million-rupee house would provide a home to a few bird families. During the hot summer days, leaving a cup or bowl of water on the rooftop would help more families. It’d definitely help if conservation is applied to all species rather than the flagship or 'fancy' species. All animals are equal and we need them. In light of the recent dengue outbreak, it must be noted that birds are one of the primary consumers of both aquatic and aerial mosquitoes. If we had enough birds and bats around us, we’d definitely have less of those mosquitoes, and the outbreak could have been prevented.

What do I get from studying birds? I get to unravel the history of biological and physiological evolutions of these beautiful animals. They’re a chapter of our natural history, a remnant of the species that ruled our earth at one point, they’re dinosaurs, and I get to study them, while unravelling the poetry of the reality that science is.

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