Tamil Nadu recently experienced a significant migration of butterflies from the Danainae sub-family, primarily moving from the Eastern Ghats to the Western Ghats throughout September. This event marked a stark increase compared to last year’s migrations during the same season.
Species such as the Blue Tiger, Dark Blue Tiger, Double-branded Crow, and Common Crow are known travelers, migrating to nearby hill ranges of the Western Ghats as the northeast monsoon approaches.
These butterflies typically journey from the Western Ghats to the Eastern Ghats and plains of Tamil Nadu in April and May, coinciding with the arrival of the southwest monsoon.
Local enthusiasts observing the migrations noted that large numbers of ‘tigers and crows’ emerged from Yercaud in the Eastern Ghats during the last week of September. The migration peak occurred from September 27 to 28, indicating a robust movement towards Salem.
Reports indicate that heavy migration continued on September 28, marked by an impressive movement rate of 10 to 200 butterflies per minute within a brief observational span in the skies over areas like Sathyamangalam, Tiruppur, and Coimbatore.
Wildlife experts monitored the migrations particularly in Sathyamangalam Tiger Reserve, with notable activity spotted over Dimbam hills, especially around September 28 and 29 when significant clusters were observed in the skies of Tiruppur.
The Coimbatore region notably benefited from this uplift, with large groups of butterflies landing in diverse areas such as Sirumugai, Annur, Mettupalayam, and Kunjappanai ghat road among others.
Ecologists suggest that the substantial butterfly migration can be attributed to favorable rainfall during the recent southwest monsoon, contrasting with the rainfall deficits experienced in the previous year which impacted migration patterns negatively.
In August 2024, Yercaud hills witnessed several rainfall events exceeding 8 cm, with Salem benefiting from 111% of its normal rainfall levels. Namakkal and Kallakurichi also reported above-normal precipitation, enhancing breeding conditions for the butterflies.
Members of the observing community have noted similar butterfly migrations occurring in areas including the Nilgiris, Krishnagiri, Hosur, Kanniyakumari, Dindigul, and Madurai, where additional species such as the Lemon Pansy, Tawny Coster, Common Emigrant, and Chocolate Pansy were also seen joining the migration.
Published on October 04, 2024, this update exemplifies the natural cycles and ecological dynamics prevalent in the region.
