COIMBATORE: The Nature and Butterfly Society (TNBS) observed that the migration of butterflies at the end of the southwest monsoon from the Eastern Ghats to the Western Ghats, an annual natural event, was back to full scale in the last week of September this year, after 2023.
The society’s members, headed by President A Pavendhan, found that in the last week of September, butterflies from the sub-family Danainae, called ‘Tigers’ and ‘Crows’ (especially Blue Tiger, Dark Blue Tiger, Double-branded Crow, and Common Crow) migrated from the Eastern Ghats and plains towards various nearby hill ranges before the onset of northeast monsoon.
The society observed that the large-scale movement could be attributed to good rainfall during the southwest monsoon season that just concluded in Yercaud Hills of the Eastern Ghats. 2023 saw poor migration due to rain deficit during both southwest and northeast monsoon until November, a report by the society said.
“This year, ‘Tigers’ and ‘Crows’ had a large scale movement from the Eastern Ghats, especially Yercaud hills, further towards Salem,” said A Pavendhan.
“The number of Tigers was high (at 95%) in comparison to Crows (at 5%). These migrating butterflies moved in the southwest direction to reach the arc of Western ghats between ATR (Anamalai Tiger Reserve) and Nilgiris. Throughout Coimbatore district, a huge movement moving in the southwest direction from the northeast.”