Friday, February 02, 2007

Migrations

It all began at the end of an uneventful day. I looked up at the sky as walked up the stairs to my room. And I saw birds. Not entirely unusual in itself, except this flock numbered in the middle tens. They wheeled in the air, changing direction with an almost audible snap, with the coordinated precision I have come to associate with migratory birds. Birds that must rely on each other to fly in harmony over long distances.

Many years ago I stood on a bund in an estuarine marsh and watched a huge flock of birds on the horizon. As the came nearer the sun glinted off their synchronous wings and they looked like a curtain rippling in a slow wind. A dense curtain made of thousands of migratory waders flying over Vedaranyam. Wheeling and moving as one body, they came closer and landed. It was an unforgettable sight.

One such curtain flutters over IISc right now. One made of thousands upon thousands of Rosy starlings. They were once called Rosy pastors, but were renamed starlings, perhaps to unambiguously link them their better known migratory kin in North America. And they are migratory, they have visited IISc before. But I didn't own a camera then and I didn't have the eyes I now have.

For a bird, a migration must be a great upheaval. Driven by the need for food, evolution has built some birds to fly incredible distances, to go from wintering grounds to breeding grounds and back. Migratory flights are often over large bodies of water where some can't land and for others over large land masses without much water in which they feed. Birds often double or more in body weight when they begin and are all skin and bones when they have arrived. They must beef up again before they return. Their digestive systems alter greatly in order to sustain these long flights. These changes might mean they need to stop and eat often in what are called stop-over locations. So not only are sites where they spend the winter important to these birds but also the IISc's they pay their flying visits to.

Their flights will be plagued not only by hunger but the old enemies predators, the cold, altitudes, the head-wind. And newer ones, man's alteration of their universe. Roads reflect light and mimic rivers, bright lights mislead them. Wires electrocute some, barbed wire fences impale others. Windmills cut these Quixotes from the skies, parabolas that collect the suns rays for heat burn them. And yet the ones that survive must go again and the young must find their way on a journey never undertaken before.

(Click on the picture below for a sense of just how many there are)

When the time is right, migratory birds show signs of Zugunruhe. Even birds that have never seen the outside of a cage slam the bars in a desperate desire to follow a map wired in their brain. du Maurier built a beautiful tale out of the frustration of birds denied their instincts by the weather and Hitchcock turned it into one of his many very watchable movies. The sheer power inherent in numbers is apparent. The motion of so many birds charges the evening skies. The usually restless crows are now nearly driven, cawing, driving, diving at the many potential targets, picking off the weak ones. Maybe even a little afraid and overwhelmed. The Mynas, relatives to the Starlings, seem to be reconciled with sharing their nocturnal roosts. Its chaos and energy worth watching as the dusk pinks over to a mellow evening.

5 comments:

Twilight Fairy said...

that closeup shot - are they related to the crow family?

Natasha said...

They belong to the same order, the Passeriformes, but different Families, the crows, the corvidae, the starlings the sturnidae.

Prashanth M said...

nice shots!! have you been to Ranganatittu or Kokkare Bellur?! Its the season now for migratory birds over there.

Swapna said...

Beautiful photos!

Natasha said...

Thanks Prashant and Swapna. I've been to Kokkre Bellur once, not to Ranganthittu. Maybe sometime this year.