Search the Internet           Tips

The Rediff Special/ Madhuri Velegar K

They flutter unsettlingly in front of your windscreen.

Wings in hues of blues and yellows, and you jam the brakes.

You don't expect to see butterflies -- big and small, colourful ones -- flitting across the long Intermediate Ring Road connecting Koramangala to Indira Nagar in Bangalore.

But since the past few days, roughly the time when the rains ebbed a bit, people have reported a number of 'sightings' of these fragile creatures flying across the road, with a few unlucky ones facing a powdery death in front of a speeding vehicle.

Education officer S Karthikeyan of the World Wide Fund for Nature (India) has a simple explanation. "They're migrating,'' he says.

From where to where?

"It's hard to say as there is no one in India who has researched butterfly migration. But we know that the Tirumala limniace (Blue Tiger), Danaus genutia (Striped Tiger), Euploea core (Common Crow), Danaus chrysippus (Plain Tiger), belonging to the family Danaidae, migrate twice a year, once before the monsoons (in April-May) and once after it (in Sept-Oct).''

Another species called Catopsilia pomona (Common Emigrant) which is also passing through comes from the family Pieridae.

According to bird watcher P A Ullas, "They are flying in a south westerly direction (towards Kerala). They breed there and the next generation or a third generation of butterflies head back to Bangalore during the months of April-May. We see so many of them, as they do not fall prey to predators like birds because the Danaidae family of butterflies are known to have a toxin in them which is bad tasting for their predators.''

According to butterfly experts, the Danaus genutia (or Striped Tiger) in India is the same as the Monarch butterfly in the US, and the Milk Weed in Africa. And research on the Monarch in the US shows that "The Monarch flies from the southern regions of Canada to the Gulf of Mexico, covering a distance of 3,200 kms. The flight speed of migrating Monarchs depends on environmental factors such as wind and direction relative to the heading (direction) of the butterfly. Their flight speeds have been measured at 5 metres per second, and 18 kms per hour but if disturbed, they can fly much faster for short distances."

"The journey back is made by another generation of butterflies which have metamorphosed from larvae to pupae to a newly born butterfly along the way. On reaching their winter destination, or their roost, they display a minimum amount of activity for a long time.'' (website: www.monarch.org)

The normal lifespan of a butterfly varies with every species. But by and large, the large adult butterflies can live from four-eight weeks, while smaller varieties live from a fortnight to three weeks. But a species of the migrating Monarch is said to live up to 10 months.

Research also shows that the Monarch, which weighs a mere .25 g to .75 g, conserves food right along the flight. The Monarch's survivor ability declines when nectar is scarce or when temperatures exceed 35 degrees centigrade. Female Monarchs or Striped Tigers are extremely choosy about the plant which they select to release their eggs. They do so only after having 'tasted' the plant with the help of their legs.

Monarch watchers state that "In the world, no butterflies migrate like the Monarchs of North America. They travel much farther than all other tropical butterflies (up to 3,000 kilometres). They are the only butterflies to make such a long migration every year. Amazingly, they fly in masses to the same winter roosts, often to the exact trees. Their migration is more the type we expect from birds or whales.

However, unlike birds and whales, they make a one way trip to areas with favourable conditions. It is their future generations (their grandchildren maybe) which return south the following fall.''

D S Srinivasa, an active member of the Mysore Amateur Naturalists which tracks wetlands and migration habits of water birds and ducks says: "I saw a congregation of roughly 3,000 butterflies, most of them were the Blue Tiger and the Dark Blue Tiger (Tirumala septentrionis) at the lake Lingambudhi in Mysore. Last year I saw more than 6,000 butterflies in the same lake area.

They could be seen in flocks of 500 or so, feeding on the plants. Today there are only a 1000, most of them have left and they are moving in a south-westerly direction. But you can still spot them in many areas right through this month and the next.''

Ullas adds: "The best time to spot the Striped Tiger in Bangalore is one or two hours after sunrise and one to two hours before sunset. Green spaces like Cubbon Park or Lalbaug could prove to be lucky for the 'spottings'. During hot days, they get fidgety and tend to fly higher.''

Karthikeyan, a keen naturalist, who has been studying butterflies since the last seven-eight years says, "There are roughly 300 species of butterflies in south India out of which 153 butterfly species are in Bangalore alone. (The Vertebrates and Butterflies of Bangalore: A checklist by S Karthikeyan). More than 70 of these species can be found in Lalbaug alone. India has 1500 butterfly species. But the only way to preserve the species and their numbers is to ensure that their habitats, which include the feeding plants for both the caterpillar and the butterfly remain intact. We can only speculate on reasons for their migration which could be in search of food plants and for mating reasons.''

Ullas says it's probably because butterflies are considered 'common place' that people do not take them seriously.

"They would rather be obsessed with big, charismatic animals like the tiger or the elephant, than spend time on a beautiful and fragile insect like the butterfly.''

Butterflies can be preserved by creating a butterfly garden and planting those plants on which the larvae/caterpillar feed and those which give nectar to adult butterflies. The Shri Chamarajendra Zoological Garden in Mysore has planted a few such feeding plants for butterflies, but besides this, there hasn't been a concerted effort to preserve or recreate butterfly habitats in India.

Those interested in watching butterflies in Bangalore can contact:

The Bird Watchers Field Club of Bangalore, which goes to the field every second Sunday of the month.

The Merlin Nature Club, started by birdwatcher J N Prasad and S Karthikeyan, also makes a nature trail on every fourth Sunday of the month.

Additional details can be obtained from S Karthikeyan, the World Wide Fund of Nature (India), who conducts butterfly workshops for nature clubs and students.

The Rediff Specials

Tell us what you think of this feature