The Western Ghats of India is considered as one of the significant biodiversity hotspots in the world. In the scorching heat of summer when the rivers, lakes, and springs start drying without water, the butterflies strive hard for their survival. At such times, the Screw pine vegetation, which is capable of retaining the water throughout the year, offers a favourable habitat for this species of butterfly, the Malabar Tree Nymph.
The Malabar Tree Nymph, idea malabarica has been given a status of the State Butterfly of Goa. The Western Ghats of India which is a home for a diverse endemic species is, therefore, identified and recognised as one of the biodiversity hotspots in the World. Malabar Tree Nymph is one of such species that is endemic to the Western Ghats of India. It dwells in the moist evergreen forest.
The favourable habitat of the Malabar tree Nymph can be identified by the presence of Screw pines vegetation along the river course. Such rivers and streams never run completely dry. Villages falling on the periphery of the four wildlife sanctuaries and several places have been identified as being the abode of the Malabar Tree Nymph. Malpon, Dhave of Sattari, Perimol of Sacorda in Dharbandora, Sulkarna in Quepem, Colamb in Sanguem, Bhatwadi - Poiguinim and Bhars in Gaodongari of Canacona are the villages where the scholars and researchers
in Zoology have a lot of scope to study the behaviour of this butterfly.
White, with black striped butterfly flying across the landscape is indeed very thrilling to witness, especially when this butterfly is hovering in the air. It glides through the air effortlessly, barely fluttering the wings. One has to look up in the canopy to find this butterfly taking circular glides and suddenly turning back and sometimes hovering at the same point as if inspecting the area. The Malabar Tree Nymph is an indicator species of rich and pristine forest.
The butterfly looks like a piece of paper. It is one among the largest butterflies of India, preferably flying high above the forest canopy. It has a wingspan of around 120 - 154 millimetres. The wings are white in color marked with black lines and the spots. This butterfly is often sighted near the perennial springs and rivers flowing through the dense forested areas. That is the favourable habitat of this butterfly.
One or two eggs are laid on the underside of the leaf. They are minute and tubular in shape. After 10 to 15 days, the caterpillar crawls out of the eggs and first eats the eggs shell and then eats the leaves. The survival of these caterpillars is entirely dependent on availability of the specific host plant. It is a plant on which the life cycle of butterflies is completed.
In Goa, the host plant for Malabar Tree Nymph which is recorded at most places, is Parsonsia spiralis. It is a thin creeper having heart shaped leaves. This plant contains toxic sap. The caterpillars when eating these leaves they intake the toxin. The butterfly too become a toxic butterfly. This acts as a defence mechanism for them and the predators keep away from this unpalatable butterfly. This is the reason why it flies at a slow pace.
The caterpillar of the Malabar Tree Nymph has a very interesting and unique style of feeding. As most caterpillars eat the leaf from its outer edge, whereas the caterpillar of this butterfly starts eating the leaf from the middle portion, leaving circular cuts on the leaves. It feeds from the underside of the leaf in order to hide itself from the potential predator. The caterpillar voraciously eats the leaves. As it grows bigger, it sheds the skin several times which is called moulting. The adult caterpillar is around 4 - 5 centimetres in length. It has white coloured stripes over the black color along with a series of red spots on either side.
The caterpillar, after a month, is converted into a pupa. It is intriguing to note that the pupa of this butterfly is three times smaller than the size of the butterfly. It is attached to the underside of the leaf. Pupa are usually found at the height of one metre from the ground. Pupa is exquisitely coloured in a reflecting gold and silver. The size of pupa is just 1.5 centimetre.
The courtship behaviour displayed by male and female butterflies is a visual treat to eyes. The butterflies descend to the closer heights where the female butterfly takes a rest on a leaf. The male butterfly hovers at a one hand distance above the female butterfly. This activity can continue for an hour. The male releases the pheromones to attract the female. During this time, the difference between male and the female butterflies is easily noted. The male has a little dull color. In Advoi village of Sattari, near the river course, there were documented sightings of this butterfly during the mating season. Butterflies gathered in large numbers in the shady area on the bank of the river. They were in pairs of two engaged in playful courtship.
In Maloli, hamlet of Nagargao, there is a sacred grove, preserved and protected by the villagers. Despite the construction of road, houses and the adjoining cultivated field, the Malabar Tree Nymph has survived in this anthropogenic pressure only because of the sacred grove. In the coolness of this sacred grove offered asylum for innumerable species for 140 million years. It is the Myristica swamp vegetation. One can witness the graceful flight of Malabar Tree Nymph. The perennial spring inside the sacred grove is believed to have medicinal properties. The Malabar Tree Nymph is the indicator of presence of fresh water. According to the data, India is facing paucity of fresh water. Protecting Malabar Tree Nymph means protecting the freshwater bodies. Through lectures in schools with the help of slideshow presentations, students get visuals from the forest and learn the importance of butterflies as being one of the largest pollinators. These pollinators help in growth of the fruiting and flowering plants. Planting of Kadamb, Jhambul, Lemon plant and Kadipatta can invite a large number of butterflies.
The International Union for Conservation of Nature (IUCN) has identified it as the red listed butterfly that is a near threatened species. This species is accorded protection in India under Schedule II of the Wildlife Protection Act,1972. Goa Government has declared it as the state butterfly. This butterfly, though does not have attractive colour and look, but one should not forget that it is the indicator of the healthy ecosystem. There is an urgent need to provide legal protection to the natural habitat of this butterfly, which in turn helps in keeping intact Goa’s water sources.
(Adv Suraj Malik is currently practicing in the District and Sessions Court in Goa. As a member of Vivekanand Environment Awareness Brigade, Keri, he delivers lectures in schools to build a strong environmental consciousness among the students)