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Migration Update: Lime Butterfly Outburst & Milkweeds
The butterfly migration is back in 2018 after missing out couple of years in trot (2016 & 2017) during March -May,
moving down in masses from the hills of Western Ghats to the plains and Eastern Ghats within Tamil Nadu land-
scape.
From end of September to November, every year, from time immemorial, Nymphalidae butterflies like Dark Blue
Tiger, Blue Tiger, Common Crow and Double-branded Crow along with a few other species will undertake their mi-
gration journey to Western Ghats from plains and Eastern Ghats of Tamil Nadu and the future generations descend
down during April- May.
Tamil Nadu Butterfly Society (TNBS) has been observing and documenting the migration since 2012 and the past
data showed that 2015 and 2016 are the worst years with respect to butterfly migration. It was almost nil and this
was attributed to the failed monsoons. Rains during 2017 South West Monsoon was more than the normal across
the state especially for the month of August and some good rains during the months of April and May too. Due to
good South West Monsson in 2017, we saw the Nymphalidae butterflies undertaking migration to the Western
Ghats. And the good rains during April- May 2017, induced a very interesting phenomenon with an unprecedented
generation of Emigrants butterfly throughout the Tamil Nadu Ghats and Plains and their migration an d they were
truly felt in Coimbatore District too.
Migration in 2018
Tamil Nadu and Coimbatore have been experiencing good rains during the current year between March and May,
and according to the IMD statistics, the rainfall received for example for the city of Coimbatore is well above the
period average (27 cm rain from Jan 2018 until June, and against a yearly average of 59 cm).
This made the conditions favourable to the Milkweed butterflies and the migration had commenced actually much
earlier than the usual dates in April, between March 17 and 21. The migration was felt and reported from all over
the district from Anamalai Tiger Reserve to Coimbatore city to the Kallar (extreme end of the district and at the
foothills of the Nilgiris). Both Euploea species (Double-branded Crow and Common Crow) and Tirumala species
(Dark Blue Tiger and Blue Tiger) were more or less equally represented. The presence of these species was seen in
good concentration as late as May 1 st week in many places, numbering to a few hundred in each place.
Migration of Lime Butterfly: When the Emigrants were in boom last year through out the state of Tamil Nadu, dur-
ing April and May, we also witnessed at certain pockets, huge presence of Lime Butterfly (Papilio demoleus, Linnae-
us 1758), from the Papilionidae family. This year too, this phenomenon was felt in Coimbatore District, especially
on the Mettupalayam- Kallar region. Along the rivers of Bhavani and Kallar, especially during morning when the
sunlight was bright and supporting, huge numbers, probably in many thousands, the Lime Butterflies were migrat-
ing. Common Emigrants and a few other Pieridae species were also migrating along with them. The open spots of
rivers were filled with mud-puddling of these butterflies. This was a treat to watch and thrilled those tourists who
were on the Mettupalayam-Ooty Road.
Jeswin Kingsly of Wildlife Wranglers, who is currently working as Naturalist in Kanha Tiger Reserve states that he
saw 1000s of Lime Butterflies migrating from hills to the plains near Kallar Mettupalayam. Major migrating species
was Lime Butterfly along with Emigrants. Lots of Mudpuddling activity is also observed in the area. It was noted
that on a peak day, 100+ species migrated per minute for two hours after which it gradually de-
creased. Mudpuddling of Lime in large numbers along with Common Mormons, Common Albatross, Common Gull,
Spot Swordtail, Pioneer and Common Emigrants were also seen.
Ramanasaran Hari, Nishanth CV and Gopalakrishnan S of Tamil nadu Butterfly Society also observed these and at
different locations of Bhavani river too. Ramanasran Hari has the following to say: “A huge number of lime, emi-
grants, gulls and milkweed butterflies are seen flying across the Kallar region. The rate of the butterflies would be
more than 200 per minute and it varied every day during this month. The dominant species in this migration is Lime
Butterfly. They moving from west to east direction and probably heading towards Bhavani Sagar River. There was
also huge mud puddling seen all around the Mettupalayam and public were excited to see that. The view of this
migration was magnificent and looked like colourful papers floating around us.”
PATTAMPOOCHI
A TNBS MAGAZINE
WINGS 2 VEINS 3
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