Sunday Read: Nature's wingmen
Bangalore Butterfly Club
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native vegetation
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Every year, during pre-monsoon months, butterflies pass through the city in large numbers. Intrestingly, years with intense butterfly activity often coincide with higher rainfall. This suggests butterflies may be responding to wind and rain patterns using nature's cues as their navigation
–Haneesh M, Bangalore Butterfly Club
When migration is mentioned, images of thundering herds across Africa's Masai Mara often come to mind. Yet, right here in Bengaluru, a quieter, more delicate spectacle unfolds every year — the seasonal migration of butterflies gliding across South India's Western and Eastern Ghats.Butterflies, despite their fragile appearance, are powerful bio-indicators of a region's ecological health. Their presence reflects the diversity and condition of local flora. Bengaluru, situated along a crucial migratory corridor, witnesses thousands of butterflies each year during their seasonal journey, according to Haneesh KM, a founding member of the. The community actively documents butterfly sightings and contributes its data to the National Centre for Biological Sciences (NCBS).'Every year, during pre-monsoon months, butterflies pass through the city in large numbers. Interestingly, years with intense butterfly activity often coincide with higher rainfall,' Haneesh observed. 'This suggests butterflies may be responding to wind and rain patterns, using nature's cues as their navigation system.'India is home to an estimated 1,200 butterfly species, of which more than 170 have been recorded in Bengaluru alone. Karnataka's Western Ghats boast over 340 species. The city's common migratory species belong to the Danainae subfamily, including the Dark Blue Tiger, Blue Tiger, Common Crow, and Double Banded Crow. While the average lifespan of a butterfly is one to two weeks, migration can extend this to three or even four weeks.The recent uptick in butterfly sightings aligns with pre-monsoon showers, says Sammilan Shetty, founder of the Butterfly Park, Belvai.'Butterflies tend to move just ahead of the southwest monsoon. This could be an evolutionary strategy to escape the harsh conditions of the monsoon, particularly in the higher elevations of the Ghats.' He notes that certain species, like the Common Emigrant, follow a coastal route along the Arabian Sea and then head inland just before the rains arrive. 'It's a carefully timed survival tactic,' he explains.Although butterfly migration is not a newly observed phenomenon, public awareness has grown significantly in recent years. But this awareness has also brought challenges. Shetty warns against replacingwith ornamental plants in artificial butterfly gardens. 'Such interventions can harm butterflies, whose breeding cycles depend on indigenous host plants. Preserving native flora is crucial,' he said.Nature enthusiasts, like Sahana M, have been tracking butterfly behaviour for years. 'I've always been drawn to birds and butterflies.They're fragile, yet vibrant,' she shares. This year, Sahana observed an early migration of Danaid butterflies. 'That often signals an early monsoon,' she points out, reinforcing the idea that butterfly patterns can act as a natural weather forecast.Butterflies, being cold-blooded, are extremely sensitive to changes in their environment. Kiran Kiggal, Associate Professor of Electronics and a keen wildlife photographer, notes that butterflies rely on sunshine and nectar. 'During heavy rains, nectar becomes scarce. So, they often shift eastward to avoid these conditions. Many begin migrating even before the monsoon sets in, sensing early showers caused by low-pressure systems,' he says.According to Dr Abhijith APC from Team Saaliga, butterfly migration is not just about movement, but survival. 'They migrate to preserve their lineage. It's an instinctive intelligence,' he explains. Many butterflies are host-specific; the Common Lime butterfly relies on citrus plants, while the Common Crow prefers Ficus trees. The pre-monsoon season offers fresh vegetation, making it ideal for breeding.Experts and nature lovers agree: Butterfly migration is more than a visual delight; it's a strategic and essential survival mechanism deeply tied to ecological balance.Bengalureans too can play a role in this natural phenomenon. Planting native species, especially host and nectar plants, can provide critical support to migrating butterflies.Creating such green corridors not only aids their journey but also helps reduce roadkill. Citizen participation in recording butterfly movements can further contribute valuable data to scientists tracking their patterns.In the heart of India's Silicon Valley, the flutter of delicate wings tells a timeless story of survival, adaptation, and harmony with nature, a reminder that sometimes, the most extraordinary migrations happen right in our backyard.
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