Searching for night-fliers in Uttarakhand6 min read . Updated: 28 Oct 2018, 03:47 PM IST
The Kedarnath Wildlife Sanctuary is a treasure trove of moth species that act as a vital indicator of biodiversity
As a 14-year-old, my first trekking experience was going up to the Kedarnath Temple from Gaurikund in Uttarakhand. Little did I realize then that an untiring inquisitiveness for moths would bring me back to this landscape many years later. The Kedarnath Wildlife Sanctuary (KWS), spread over 975 sq. km, houses the most fascinating biodiversity as well as medieval temples. With over 200 different species of rhododendrons (locally known as the buransh), the state flower of Uttarakhand, the area is resplendent in several shades of red and pink. Vast swathes of lush green oak (banj) forests cover the gentle slopes of the mountains. Spread over Chamoli and Rudraprayag districts of the state, the sanctuary is one of the most prominent protected areas in the western Himalayas, and home to the endangered musk deer.
The region was previously unexplored for its moth fauna, and the complex and dynamic nature of the insect’s ecosystem intrigued me.
Understudied and mostly outside the public gaze, these night-fliers are often described best by connecting them to their popular cousins, the day-tripping butterflies.
There is a constant struggle to preserve nature, as every year, between May and October, thousands of people embark upon the pilgrimage to the Kedarnath shrine. The 14km trek to the shrine, starting from the roadhead at Gaurikund, passes through the sanctuary. The other medieval Shiva shrines in the sanctuary area that attract devotees are those of Mandani, Madhyamaheshwar, Tungnath, Ansuya Devi and Rudranath.
Apart from the pilgrims, many birders and wildlife photographers also throng the area to get the desired “eye-level shot" of the Himalayan monal, the koklass pheasant, as well as the musk deer and the Himlayan tahr, among other high-altitude fauna. “Monal dikhna toh Mahadev ki kripa hain (the Himalayan monal can be seen only with Lord Shiva’s blessings)! " says a pilgrim as well as a bird lover, whom we met on our trek to the Deoria Taal, a high-altitude lake within the sanctuary, which is popular for its stunning views of the Chaukhamba massif.
With funding from the Rufford Foundation, UK, I undertook a project to explore the moth diversity of this protected area. I have been studying this in the western Himalayas for the past four years, but this area had remained unexplored. I was keen to understand moths in a scenario where humans and nature are at crossroads.
Looking out for moths was an engrossing experience in this landscape, with its varying habitats, ranging from temperate, coniferous and alpine forests to alpine meadows (bugyals). The sanctuary also possesses a diverse climate and topography, with dense forests of pine, rhododendron, birch, and banj oak. Every night we would set up a light trap (to attract and examine flying insects) for 4 hours and wait for moths to get attracted, and record every species; some of which I was encountering for the first time.
It started out on a great note with the Indian moon moth (Actias selene) gracing the light-trap sheet on the fourth night. It is a species that is widespread in South and South East Asia, but I had never seen this beauty in the wild. It was a normal light-trapping session within an oak-dominated forest, when right towards the end of the sampling hours we went to check the trap and Prabhat Singh Bisht, my field assistant, exclaimed “Itna bada moth aaya trap pe (such a huge moth is at the light trap)." There it was, a huge, pale-green female Indian moon moth, with the eponymous lunar markings on its forewings and elongated hindwing tails. These markings serve as a defence mechanism to confuse echolocating bats which prey upon them. Another night, just when I was wrapping up my trap, with startling sambar and barking deer calls piercing through the silence of the forest, a peach blossom moth (Thyatira batis) settled on the wire attached to the light. It is a beautiful moth with pinkish spots on its brown forewings and is found across Europe and Asia.
An interesting observation was when a large tiger moth (Aglaomorpha plagiata) started secreting a yellowish liquid from the back of its neck region (between the head and the thorax) as it rested on the light-trap sheet. This liquid is a defence mechanism, one that makes the moth unpalatable to predators. This behaviour has been reported in the wood tiger moth (Arctia plantaginis) and several other tiger moths (Family Erebidae, subfamily Arctiinae). The sanctuary region is moist and oak dominated, so there’s an abundance of the gypsy moth group (genus Lymantria), where the males are dark brown and smaller compared to the females with their white wings and black markings. We found several other interesting species of moths (from the end of March till the end of May), adding to the biodiversity of this area—like the silk moth, the Naga hawkmoth, the common grizzled hawkmoth, and many others.
What struck me was the awareness among local Garhwalis and their willingness to protect the forests and the wildlife. Hardworking and shy as they are, their days begin and end quite early. They tried to understand what we would be doing in the middle of the forest at night and what exactly moths were! As I was explaining my work, Gudduji (a local resident who hosted us at Ansuya village) exclaimed “Arre yeh toh pwotai hain, jo ghar mein light pe aati hain (ah! It is the pwotai which often comes to the lights around our home)". I was quite overjoyed to know that moths actually have a local name.
In such a biodiverse Himalayan landscape, one cannot miss out on any opportunity to look out for species other than the focal group of the study. Working on a nocturnal taxon and with most of the evenings washed out by rains, we had the mornings to explore the region. Armed with binoculars we would set off to observe scarlet finches, alpine accentors, koklass pheasants, Himalayan monals, the fulvettas, the tits, the forktails, the Himalayan tahrs, and many other bird and mammal species. As I started my field season in spring-summer, high-altitude birds like the snow partridge would generally migrate up along the mountains with the receding snow.
One day we hiked up to the 3,800m high pinnacle of Chandrashila (which stands for “moon rock") above the Tungnath shrine (the highest of the Panch Kedars). As we reached the top, a hailstorm began. Prabhat asked me to follow him to the site where he was quite sure we would spot a snow partridge. Our walk through the hail was rewarded when we saw three of these birds, a wonderful sight that’s still etched in my mind. Among nocturnal species, we would occasionally hear the distant “hoop-hoop" of the elusive Himalayan wood owl and the shrieking call of the spot-bellied eagle owl, during sampling (light-trapping) sessions in Bulkhan and Mandal villages inside the sanctuary. One night, as we were waiting to check the light trap, a pair of eyes shone in the dark in the branch of a nearby tree. Hurriedly, we grabbed our head lamps and torches and approached the tree to see, sitting quietly, oblivious to our presence, a red giant flying squirrel.
Unravelling the moth diversity of such a diverse Himalayan landscape is like finding the missing piece of a jigsaw puzzle. Mountains have always been considered centres of spectacular biological diversity and the Himalayas are certainly so. But human activities are threatening this important landscape. Moths have been proven to act as indicators of forest health, and this is extremely important in the present situation of habitat degradation and climate change. Studying their ecology would be helpful to understand the changes in the ecological hierarchy. But, very often the conservation efforts for moths would be directed towards the Himalayas as a unit, but because of the inherent diverse nature of this mountain system, area-specific conservation should be targeted.