The World Tiger Beetle Day celebrations draw attention to these lesser-known group of colourful insects

The World Tiger Beetle day celebrated on November 11 hopes to build respect, nurture, and conserve this lesser-known group of colourful insects

Many beetles are dark-coloured and go about their business in the underbrush, unseen by human eyes. The charismatic tiger beetles, a group of predatory insects, on the other hand are hard to miss. Their metallic-green bodies sparkle as they perch in the open. One of the species, the Enigmatic tiger beetle discovered at Ammayanaikanur in Dindigul district of Tamil Nadu hasn’t been seen for over 200 years, making it possibly extinct. Another one called Bengaluru tethys documented in Bengaluru in the 1990s is threatened due to rapid urbanisation the city has undergone.

As November 11 is now officially celebrated as World Tiger Beetle Day, which also marks the birthday of David Pearson, a trailblazer in tiger beetle research, conservation, and global outreach, a series of workshops and talks happen across the country that hope to build respect, nurture, and conserve the six-legged tigers. Pearson is also a primary author of the Field Guide to the Tiger Beetles of India.

At a virtual get together organised by South Asian Invertebrate Specialist Group (SAsISG), based at Zoo Outreach Organisation in Coimbatore, a diverse group of students, naturalists, wildlife educators, conservationists, nature lovers, and researchers listened in apt attention as David gave a talk on tiger beetles, their natural history, fascinating behaviours, diversity, ecology, and conservation methods. One of the recommendations is to create more awareness and interest in this lesser-known group of insects. “Tiger beetle is an indicator species of environmental and ecological health. The trends, diversity, and individual numbers of tiger beetles determine the quality of habitats available for biodiversity and for agriculture,” says Sanjay Molur, executive director of Zoo Outreach Organisation.

India has 241 species of tiger beetles, which is the third highest number of species in the world. To understand more on the tiger beetles, researchers across India, working on tiger beetles came together at IUCN Red List Assessment workshop conducted by SAsISG in May 2024. The team assessed 122 species endemic to India, which is tentatively 46 per cent of the species threatened with extinction. Plantations, mining, tourism, and urbanisation are the major threats for this group.

For example, Spindle-necked Tethys found only in Ponmudi, Periyar National Park of Kerala is threatened by plantations and tourism. While the Speckled Tehthys found in Anaimalai, Nilgiri, and Meghamalai foothills of Tamil Nadu at 300 to 700 metres altitude in shrub forested slopes is highly threatened by tourism, the Waxen tiger beetle, documented in 1987 at a single locality of Manapad district, Tuticorin in Tamil Nadu hasn’t been seen since.

“Tiger beetles are top-predators of the insect world characterised by their large bulging eyes, long legs, and long curvy jaws. They are excellent hunters and are known for their running speed. These beetles are spectacularly coloured, while some have restricted distribution, some have pan-India distribution ranging from moist forests to scrublands,” says Usha Ravindra, research assistant at SAsISG.

 The Thin Brush, endemic to the Northeast has beautiful metallic colourations and was last documented at south eastern Meghalaya at an altitude of 1400 metres. tiger beetles play crucial role in managing other insect populations, and maintaining ecosystem balance as the majestic beetles are the friends of farmers. 

A number of species are endemic too. For example, the Violet-sided tiger beetle, a large and charismatic tiger beetle, easily diagnosed by its blue-green and purple patches on the edges of its head is restricted to the Jorebungalow forest region of Darjeeling. The Wrinkled Knobby, a black and yellow beauty, is a rare species confined to small area at the foothills of the Eastern Himalayas in Darjeeling whose natural habitat is rapidly declining due to tourism and increased tea plantations. It calls for extensive surveys and behavioural studies to find out ways to conserve this beetle.

Published - November 19, 2024 03:06 pm IST