A view of Nubra Valley in Ladakh, where the author counted around 30 species of moths in a single night. Photo: Sarthak232001 – CC BY-SA 4.0
It was with some trepidation that I began planning a butterfly and moth watching trip to Ladakh in 2016. Already facing scorn from friends for planning a Lepidoptera-focussed itinerary in Ladakh, I wondered: Would the cold desert landscape of Ladakh yield any moths? With nothing to lose I decided to take the plunge and carry my moth gear, consisting of a white moth screen, a mercury vapour bulb, and an actinic tube light as back up.
The first few nights at Leh were disappointing. There was too much light pollution at the guesthouse that we were staying at and my moth lights attracted no moths at all. Our next stop was in the small village of Tigger in the Nubra Valley. The area around this village consisted of agricultural fields and fruit orchards, and as I figured out later, excellent habitat for moths. We hit the jackpot on our first night at Tigger. More than 70 individuals and perhaps 30 species of moths appeared on the white wall where we had set our moth-attracting light bulb. The highlight of our moth watching in Ladakh was seeing three species of hawkmoths. As only six species of hawkmoths are recorded from Ladakh (Smetacek & Kitching 2012), spotting three of them was nothing short of incredible.
To the uninitiated, hawkmoths are stout-bodied, moderate to large moths that are powerful fliers. Most hawkmoths are nocturnal, though many bee or hummingbird hawkmoths are diurnal. Most hawkmoths feed on nectar from long-necked flowers using their long proboscis (tube-like mouthpart), and play a crucial role in flower pollination.
The author was part of a team at Tigger, Ladakh which, in 2016, rediscovered the sea buckthorn hawkmoth (Hyles hippophaes bienerti) after a hundred years. Photo: Sanjay Sondhi
The very first hawkmoth to appear at Tigger was the sea buckthorn hawkmoth (Hyles hippophaes bienerti). First one, then two, then half dozen of these moths appeared, attracted to our light. As we read up on this species, we discovered that Nubra Valley was the only known location for this species in India, and it was known only from a single specimen in the Natural History Museum, London, collected by A. Avinoff in 1912, and that we were the first people to report this species from Ladakh after 100 years! As its name suggests, this moth species lays its eggs on the sea buckthorn plant (Hippophae rhamnoides).
Overharvesting of sea buckthorn berries in Ladakh threatens the sea buckthorn moth, which lays its eggs on this shrub. Photo: Karunakar Rayker – CC BY-SA 2.0
The southern eyed hawkmoth (Smerinthus kindermannii) uses its brown forewings to camouflage itself, but when threatened, it flashes its pink hindwings to deter predators. Photo: Sanjay Sondhi
The second hawkmoth we saw at Tigger was a single individual of the southern eyed hawkmoth (Smerinthus kindermannii). With wonderfully patterned wings for camouflage, this hawkmoth lays eggs on the weeping willow tree (Salix babylonica), a common tree in the Nubra Valley.
The bedstraw hawkmoth (Hyles gallii) lays eggs on the Himalayan prostrate spurge plant (seen here), which is often overgrazed upon by livestock near villages. Hawkmoths struggle to survive when their host plants are wiped out by anthropogenic pressures. Photo 1: Sanjay Sondhi Photo 2: Jiang Tianmu/Shutterstock
The third moth that turned up, once again attracted to our moth light in the small village of Spangmik, was the bedstraw hawkmoth (Hyles gallii). It is known to lay its eggs on small herbs such as bedstraw (Galium sp.) and Himalayan prostrate spurge (Euphorbia stracheyi) that grows in the sparse, barren landscape that typifies Ladakh.
The bedstraw hawkmoth caterpillar has two rows of ten eye-like yellow spots on its back and a red horn above its tail. Photo: Ann-Charlotte Jansson Public Domain
All the three hawkmoths we spotted are only recorded from Ladakh in India. Intriguingly, all of them have pink on the hindwings, while the rest of the moth is a general dull brown or grey. Most hawkmoths sit with their hindwings covered, which helps them camouflage themselves. The pink on the wings is perhaps used to startle nocturnal or diurnal predators, when the moth feels threatened.
Sadly, like all of Ladakh’s wildlife, hawkmoths too face anthropogenic threats. Sea buckthorn berries are being over-harvested for their juice, whose popularity is growing with unsustainable and growing tourism in Ladakh. Spurge and bedstraw, herbs that grow on stony slopes and meadows are being over-grazed by livestock near villages. Without their specific larval host plants to lay eggs on, hawkmoths cannot survive. Already faced with harsh conditions in a cold desert, humans need to give hawkmoths (and other insects), the space to survive.
