For Harriers, finding prey in degraded grasslands and savannahs can be a laborious, energy consuming activity in late winter and summer. But the harriers have a secret trick! Like Drongos and Kestrels, they flock around raging daytime fires in the countryside in search of easy prey, escaping or killed by the fire. We witnessed this behaviour in Harriers first hand when a fire broke out unexpectedly one night. It was a cool January night and the birds were at roost in the darkness.
In a bizarre turn of events, the burning of a fire line that was meant to keep the fires under control spun out of control and led to a raging fire. At full blaze, when the adjoining hillocks were lit in deep red, the harriers in the grassland took to the air. Against the backdrop of the fire, we could see the Harriers seeking safer roosting areas a few hundred meters away.
Fire is a common occurrence around savannahs and grasslands of India. Harriers are well adapted to deal with such eventualities and even benefit from such fires as was obvious the next morning at the burnt patch.
Harriers usually find prey by scanning the terrain as they glide a few feet above the ground methodically, their vision focused on the grass. But that morning, there were no signs of the intense scans by harriers. They simply converged on the burnt patch scanning for fried and roasted grasshoppers, which are otherwise are so tedious to spot.
The Harriers' obsession with this uncontrolled fire was so intent that one bird barely noticed us walking towards it. We got as close as five to six feet’s distance when its senses finally kicked in and raised the alarm to fly away from the biggest of all predators!
It was a scientific experiment we could never have designed. As students of ecology, it was sheer luck! Harrier diet is usually analysed by picking pellets (undigested regurgitated bone, scales, feathers and hair fragments) from roosts, then dissecting and documenting them. But during this event, the fire had burnt everything, including the pellets, leaving behind nothing but soot. Even the dissected parts of the hoppers they ate were left as charcoal. Our job of sifting through the remnants was so much easier than in the expanse of tall grass vegetation.
Pellet collection is the easy part as long as the roosts are well monitored and marked in the grassland. Pellet dissection, on the other hand, can be a messy, unpleasant affair. After a long day's work at dissecting pellets, even a bowl of delicious fried food is likely to be viewed with suspicion! And then there are the jokes we have to put up with from friends and colleagues; “come what may avoid using the words – from my pellet analysis – in your talks and presentations”.