Kasavanahalli Lake used to be my little secret. Off the traffic-clogged Haralur and Sarjapur roads in suburban Bengaluru, this wetland, tucked in the heart of a residential neighbourhood, was my daily getaway for exercise, fresh air and meditative birding.

I discovered the lake years ago as an inviting blue speck on Google Maps. After cycling through backroads, I found myself facing a shimmering water body fringed by grand old Ficus trees and clumps of eucalyptus and acacia, surrounded by marshlands and even a patch of grassland. It became my morning haunt.

A view of Kasavanahalli Lake from the walking track

I used to get there just as the guards opened the gates, before the morning walkers arrived, and just as the fisherfolk in their coracles were hauling in their catch. Unlike Kaikondrahalli Lake, its popular northerly neighbour, Kasavanahalli Lake has seldom been the focal point of Kere Habbas or environmental activism. Yet, with its biodiversity, scenic sunrises and sunsets, and its organic links to the city’s web of freshwater wetland ecosystems, it has enthralled me for years. 

A huddle of Asian Openbills feeding in Kasavanahalli Lake

From basking keelbacks to skulking mongooses, from thousand-strong flocks of Rosy Starlings in the season, to a pair of amorous Shikras raising a brood, from a solitary Indian Roller to a secretive family of Bronze-winged Jacanas, from Bark Mantises and butterflies to orb-web spiders, this lake has gifted me with many memorable wild encounters.

A Eurasian Coot scopes out a nest of reeds

In the last few years, construction activity around the lake has intensified. The original neighbourhood of independent villas has transformed into a festering eyesore of towering high-rises. These buildings pump gallons of raw sewage into the drains that skirt the lake bed. Despite an industrious citizen-led tree planting drive, which has greened the walkways surrounding the lake, the water inflow has been choked, drying up parts of the lake. 

The birds, however, have kept their date with the seasons. At least so far.

A Great Egret (foreground) and a Grey Heron fish side by side in the marsh surrounding the lake

On an overcast monsoon morning, I chanced upon a family of Eurasian Coots, the chicks newly fledged, emerging from the reed beds. I had watched the adults nesting just a few weeks earlier. An Indian Spot-billed Duck looked slightly overweight until she spilled her secret: eight fluffy ducklings trooped out of her folded wings like soldiers from a Trojan Horse. Cattle Egrets and Pond Herons looked ravishing in full breeding costume. Grey-headed Swamphens, marked in my checklists by many aliases depending on the edition of the field guide I was using, glistened in resplendence as stray spells of sunshine flecked their iridescent hues. A tableau of egrets — Great, Intermediate and Little — foraged side by side with Grey Herons and Purple Herons, resembling an animated page from a birder’s textbook. White-throated Kingfishers chuckled merrily while the resident Common Kingfisher kept a low profile, zipping away like a dart at the sound of my footfalls. Occasionally, a Eurasian Hoopoe or Common Hawk-Cuckoo would grace the checklist.

One of a pair of Brahminy Kites that has successfully raised brood after brood near the lake

Not a morning person. A Spotted Owlet at Kasavanahalli Lake

Winters brought migratory warblers and wagtails to the environs of the lake. One morning, following the trail of the season’s first Blyth’s Reed Warbler, I saw a fine Checkered Keelback sunning itself on the path, oblivious to the party of senior citizens arriving to conduct their laughter club. Wagering that they wouldn’t be amused by this sight, I gently coaxed the snake off the track to the water’s edge. On another occasion, I saw a group of children inspecting a tiny Brahminy Worm Snake. It took an on-the-spot nature workshop to awaken them to the reality that they had just saved a beautiful reptile from being trampled.

A Three-Spot Grass Yellow at Kasavanahalli Lake

A Bark Mantis tries to blend in

Whatever the season, the old fruiting Ficus on the northeastern bank of the lake sheltered many surprises, including a pair of Spotted Owlets that shrieked invective if roused from their diurnal snooze. Rose-ringed Parakeets and barbets of two species — the White-cheeked and the Coppersmith — investigated the hollows, each for their own reasons. A Black Drongo occasionally kept guard, joined in winter by its cousins — the Ashy Drongos. When summer showers raised swarms of winged termites or ants, Green Bee-eaters joined the all-you-can-eat food festival.

A fruiting Ficus tree on the lake perimeter

A Pale-billed Flowerpecker enjoys a wholesome meal

On the eastern side, a fetid open sewer patrolled by White-breasted Waterhens runs beneath the maze of woodland and tangled shrubbery, emptying into a marshland choked with water hyacinth. Here, Black-headed Ibises foraged alongside Glossy Ibises. To the far edge of the marsh is a grassy verge where boys from a nearby shanty play cricket on weekends. Pied Bushchats and Ashy Prinias held court here. When all was quiet, a troika of Grey Francolins arrived, announcing their presence with reverberating calls.

A Purple Swamphen at Kasavanahalli Lake

The Indian Spot-billed Duck is the most common and abundant resident species of duck here

Over the years, I have made fifty or more checklists here. Last winter, however, I recorded a number of species I had not seen here before. The receding water attracted waders like Black-winged Stilts, Wood Sandpipers, Green Sandpipers, Little Stints, Little Ringed and Kentish Plovers, apart from Painted Storks, Spot-billed Pelicans and Asian Openbill Storks who made ravenously for the stranded big fish. Garganey and Northern Pintails dabbled in the shallows. As these birds thronged the depleted water body in enormous flocks to scoop up the last supper, they aroused the interest of a lurking Western Marsh Harrier. A pair of Pied Kingfishers took turns to hover over the desiccating swamp, looking for an easy bite.

A variegated flock of waterfowl makes for productive winter birding at the lake

This last summer has been harsh, and the weak monsoon has not helped. The water has all but dried up. Patches of dry land have been taken over by weeds. Cattle graze on the last of the grasslands, while humans and feral dogs have access to what were once safe hiding places for birds.

With the lake drying up and sheltered areas getting exposed, feral dogs become a threat to the waterfowl

The dry lake bed also makes provides easy access to humans, thereby discouraging the birds

Ideally, this natural cycle of the lake drying out and filling up with rainwater should not cause alarm, but the heightened human interference has raised my hackles. For the last few months, my access to the lake has been cut off. Tipper trucks ply on the rutted roads, raising clouds of gritty dust while yellow JCB excavators blocked my path. Officials have brought in equipment, apparently, to channel the sewerage system around the lake. There is hearsay that they intend to deepen the lake and “beautify” the surroundings. They have already razed the reed beds and turned up the earth.

An Asian Openbill basks in the reflected glory of urban housing

A Red-wattled Lapwing calls mournfully from atop of a mound of earth used to fill the marshland

The nesting coots were nowhere to be seen this season. There were fewer Spotbill Ducks than usual. Only a Red-wattled Lapwing sat dolefully upon a mound of excavated earth, asking the question it always asks.