Meet Spiny, the Only Herbivorous Lizard Species in India

When asked to imagine a place that is buzzing with wildlife, most people think of a forest with thick foliage and tall trees — a far cry from the seemingly inhospitable environs of a desert with its arid climate and vast stretches of sand dunes. In reality, habitats like the Thar Desert are diverse in their own way. They are interspersed with rocky hillocks, sparse vegetation, and sandy and gravel plains, and are home to numerous species of wildlife, some endemic, others rare, or critically endangered. Spotting wildlife here can be a challenge, but observing creatures in the wilderness is great fun, as they have evolved mechanisms — both behavioural and physical — to tackle extreme temperatures.

In particular, it is the herpetofauna (reptiles and amphibians) that take one’s breath away. For instance, the saw-scaled viper, with its unique side-winding style of locomotion, has only two points of its body touching the surface which helps the snake gain traction on loose sand. Then there’s the fringe-toed lizard that raises its limbs alternatively to cool off while feeding on the hot ground during the day.

The spiny-tailed lizard, or ‘Spiny’ as we fondly call it, is another fascinating creature from the Thar Desert. This diurnal, ground-dwelling reptile is the only herbivorous lizard species currently known from the Indian subcontinent. Found in small, fragmented populations across arid regions of Kutch in Gujarat, Rajasthan, Spinys support the desert ecosystem through seed dispersal and are a favourite food source for predators. Their preferred habitat is open grounds with grass, shrubs, interspersed with khejri (Prosopis cineraria) and ker (Capparis decidua) trees.

Spiny-tailed lizards live in colonies with several individual burrows close to each other. Each burrow has a single opening that extends to form a spoon-shaped tunnel, complete with a chamber to make a U-turn to come back outside. The lizards spend their days outside, mostly foraging, and when the day’s activities are complete, they retire to their burrows and cover the entrance with loose sand. This ensures safety from predators, and from occasional rain.

One morning, while, driving through a small village in Thar, we saw the heads of a number of spiny-tailed lizards, peeping out of their burrows, and decided to stop and observe their movements. Upon closer inspection, we saw that the mouths of many burrows were still sealed, meaning most of the colony was yet to emerge. It was still early for peak activity to begin. We positioned ourselves near a closed burrow, under some shade, and pulled out our camera gear and water bottles. We knew it was going to be a long day ahead.

Around 10ish, we saw some sand flying out of a burrow, like a little volcano erupting. It would stop for a while and start again, and this went on for a few minutes. Then, after a brief break, there was some movement in the burrow and we saw a head appear.

Spiny-tailed lizards are extremely alert and well aware of their surroundings. Before emerging fully, they pop their heads out to study the situation and check if it’s safe. If the coast is clear, their hands and the rest of the body follow. Once outside, they lay completely still, basking in the sun in an open area close to their burrow. Exposed but on full alert for any threat. The one we were observing was an adult with a beautiful, blue spiny tail.

By noon, Spiny was actively foraging and chomping on the grass around its burrow. Once, it ventured into the territory of another Spiny and got chased back to its own area. Even though they live in close proximity to each other, they seemed very protective of their territories. Fighting and chasing each other seemed to be a common occurrence between them while foraging.

At a distance, we also saw a laggar falcon scanning the ground for prospective prey. After a dozen swoops, it finally scored a spiny-tailed lizard, only to be mobbed minutes later by a tawny eagle who tried to steal the catch. As it turned out, it was the falcon’s day, and it disappeared shortly after, to relish its hard-earned meal. As for our Spiny, it had successfully made its way back to its burrow, and a little volcano of sand later, it was safely sealed inside.

Spiny-tailed lizards are agile and alert. Photographing them can be a task! Out of all the photography trysts with them, one of the most challenging images to conceptualise was the image of a spiny-tailed lizard and its desert habitat. On another occasion, we decided to place our camera near a closed burrow. Initially we only left the camera there for short spans of time, to ensure we weren’t hampering the daily activities of the reptile. As the lizard got more comfortable, we increased the number of hours, until we were finally able to capture the animal in all its glory — after six long days.

The months preceding winter, in September-October, is the busiest time of year for spiny-tailed lizards. Following the monsoon, the vegetation is relatively rich and widespread, and the Spiny population spends much of its time eating and gathering additional fat before hibernating in the winter. We call this time of year ‘feeding frenzy’.

This season coincides with the arrival, to their wintering ground, of migratory raptors like the steppe eagle and long-legged buzzard. Resident raptors too join this feeding frenzy, as do desert foxes, desert cats, and reptiles like the red sand boa, spectacled cobra and desert monitor lizard. The abundance of the spiny-tailed lizards ensures easy prey for these ravenous predators.

There are much larger threats faced by spiny-tailed lizards today. They are vulnerable to habitat loss and degradation, as well as commercial exploitation for meat, skin, and oil. Even in conservation circles, reptiles do not attract as much attention as iconic species like the big cats. Unfortunately, the desert ecosystem has the same problem. There are few species with glamour quotient here, and as a result, the threats faced by this one-of-a-kind habitat remains largely ignored. Every year, more of it is being lost to agriculture and large industrial projects involving windmills and solar power plants, which in turn lead to road expansion, land procurement, etc., bringing irreparable changes to the ecosystem.

Species such as the spiny-tailed lizard have evolved in specific ways to adapt to their habitat, and can only thrive in the desert ecosystem. Efforts like ‘greenification’ drives, to convert deserts into a forest scape might drive these species to extinction. Climate change is also constantly altering the desert habitat. Non-seasonal rains encourage the spread of fast-growing grasses and shrubs like the invasive Prosopis juliflora, a species of mesquite, which has impacted the spread of native vegetation.

The desert ecosystem must be protected, because its role in our planet’s ecosystem is as significant as a rainforest. In India, the heat of the Thar Desert creates a low-pressure region contributing to the southwest monsoon in India. Without the desert, the rain patterns would alter in unforeseen ways.

Most importantly, our desert ecosystem must be protected for the life it supports. After all, the desert is not so deserted at all.