Pilgrims in a skyscraper – The Hindu

Minion | Photo credit: Gnanaskandan, PRW

Aura is perched on the edge of a ledge 29 dizzying stories high, like a Marvel superhero. Overlooking a wetland domain surrounded by the city and a road that turns to the southwest, threatening further development. He scratches his chin sleepily, eyes closed against the blooming March sun. Aura is a female peregrine falcon (Falco peregrinus calidus). Its distinctive dark hood, white cheek patches, and slate-blue back contrast with a light belly marked with horizontal bars and arrowheads. A light peach color fades over his shoulders and chest.

I am here with members of the Madras Society of Naturalists’ raptor study group. The MNS has been tracking pilgrims in Chennai for almost two years, one of the first such studies in India. The study has revealed >35 people in the city; including some shaheen during the southwest monsoon months. shaheens (Falco peregrinus peregrinator) are a smaller, brighter-plumaged subspecies that resides in India and makes local movements. Unlike Aura, whose breeding grounds are in the far north, somewhere between the Eurasian tundra and eastern Siberia.

Dozing on another steep ledge to our right is a tiercel (male, smaller as is typical of hunting birds of prey), Minion. From time to time he is awakened from his trance by some wild rock pigeons, which frolic irreverently a few meters away from him. They may share an attic today, but peregrines and rock pigeons evolved together in their traditional homes: crags and steep cliffs. Both are designed for speed; bulky bodies and deep, muscular chests powered by pointed pinions and short tails. Faced with prey with a specific skill set, peregrines evolved to kill birds by flying quickly through the air.

Successful conservation

They hunt from high positions or rising to great heights. Once a target is locked on, it simply falls from the sky. The wings fold back in a searing dive (“lean”) to strike their prey with giant, clenched claws as they swish by. Most of the birds are stunned or killed by the impact, and the peregrine climbs back up to catch the falling bird. If they fail, the hawk will pursue them in a horizontal chase where zigzagging pigeons, plovers and swifts are more evenly matched in terms of speed. Pilgrims have been recorded ducking at a blinding speed of 389 kmph!

Peregrines are symbols of both successful conservation efforts and pure adaptability. By the late 1970s, they were in sharp decline worldwide and many local populations became extinct; decimated by the excessive use of pesticides such as DDT that weakened their eggshells. The phase out of DDT and painstaking breeding programs brought them back from the brink. When populations slowly recovered, a new trend was observed in the 1990s. Pilgrims began to move to the cities.

Where do living things thrive? Wherever there is abundant food and safe shelter. The pilgrims simply looked for places that were the best approximations to their natural cliff habitats: skyscrapers and apartments with ledges and overhangs, tall bridges and spiers, and pylons. Not only as viewpoints but as nesting sites.

A survey carried out by the British Trust for Ornithology in 2014, covering 1,769 breeding pairs in the UK, found that urban peregrines were faring better than in their traditional homes. As cities became increasingly better lit, some pilgrims became partially nocturnal, targeting flocks that migrated at night. From personal experience, most prefer west-facing skyscrapers with shaded ledges at least 15 to 16 stories high. Many people choose pylons, especially near wetlands. Like the dusky tiercel I saw last week, chasing a flock of flickering plovers in Kelambakkam.

Breeding pairs and pigeon hunters.

This movement also coincided with the explosion of feral pigeon populations. In India, their number has increased by 150% in the last two decades, as a result of the growth of cities, astrology driven food and the loss of green spaces. Some of the other predators of pigeons, such as the shikra which depends on tree cover, suddenly became less relevant.

Pigeons negatively affect local biodiversity by reducing the number of birds such as sparrows and mynahs (due to their large number and direct competition for food sources), and even food plants (they tend to attack young trees and grains). Worse still, they carry the threat of disease: there is a growing trend of hypersensitive pneumonia among people overexposed to pigeons. Give importance to the presence of urban pilgrims; In some places, pigeons make up 80% of their diet.

What also helped is that people kindly agreed to have this charismatic hunter as a nesting neighbor. London has 30 breeding pairs, some with a live feed of the nest! Shaheens have been sporadically reported to nest in Mumbai, our highest city. But relatively little is known about the number, movements and habits of pilgrims in Indian cities.

In Delhi, a handful of birds are known to frequent the same skyscrapers annually. But most other sightings come from wetlands and individuals are not tracked. What’s up with the vertigo-inducing jungle of skyscrapers spread across the NCR? This is where dedicated and technically grounded citizen science programs, like MNS, come into play, bridging the gap between nature and us. Long may the pilgrims rule our lonely celestial islands of cement.

The second in a series looking at urban spaces as havens for biodiversity and often overlooked species.

The author is a bird watcher and writer based in Chennai.