The shapers of jungles

Kanha is one of the most beautiful national parks. The first thing you notice are the enormous sal trees (Shorea robusta) forming patches with closed canopies. Then you notice that they are actually stands of trees in a larger grassland. The stands are carpeted with fallen leaves. The sunny grasslands are full of herds of chital (Axis axis, spotted deer). At the edges between the open grasslands and the forest are the more cautious sambar (Rusa unicolor) and barasingha (Rucervus duvaucelii, swamp deer). But if you look closer you see the species that shapes the landscape by removing litter and tilling the ground: termites. Some are visible by their mounds dotted throughout the forest, others hide in living trees and dead logs.

I spent quite a bit of time trying to figure out how high the termite mounds were. It sounds silly, but then I was in a jeep which spent three days rushing through the forest in search of tigers. Most tourists holiday in nearby resorts, and spend their times in swimming pools and air-conditioned rooms, making a couple of forays into the jungle. Of those who come to the forest, most are interested in tigers. So tigers are a boon to the locals who make their living on tourism, and their behaviour is geared to such people. A very few visitors come to the forest to see more, and the guides and jeep drivers are happy to talk to them about their own experiences. But you just cannot get off jeeps to make measurements. So I had to improvise by taking photos of termite mounds with different things to give a scale. Everything simplified when I saw two people, forest workers, walking between two mounds. That photo clearly told me that the large mounds were about two meters high. I saw the Northern plains gray langur (Semnopithecus entellus, hanuman) crouched behind a smaller mound. These langurs are about a meter tall. So that sort of verifies my estimate by eye that the larger mounds are twice as tall.

I’ve found termites (order Blattodea, infraorder Isoptera) fascinating for a while. They are cockroaches (order Blattodea) which adapted to eating wood by harbouring a microbiome of bacteria, protists, and fungi in their stomach. In fact, the study of termites gave the first clue that many animals could have flourishing ecosystems inside them, a discovery that is now increasingly used in treating human disorders like Type II diabetes. In a forest they munch up fallen logs and leaves and are important recyclers. But they bore into trees and wood, which makes them pests for us at home or in farms. This bunch of cockroaches also developed eusocial behaviour some time in the Triassic or Jurassic, becoming differentiated into castes of workers, queens, and kings. When I was young I would see yearly swarming of termites, as a queen and her retinue set off from their old palace in search of a new home. So I know that a termite is only a couple of millimeters in size. The mound is a thousand times larger. Calling it a palace is shortchanging the mound, because I know of no human queen who lives in a two-kilometer tall palace. Perhaps one should compare it to a medieval citadel, a city which houses the court and also all the industry which supports it.

I’d spent some time photographing termite mounds up close in the Bijrani range of Corbett NP. You can see from these photos that they have a contoured surface which is rather smooth. The material glitters in the sun, which makes me think that bits of minerals in the soil, or insect chitin could be incorporated into it. I found an interesting group of papers which studied the strength and engineering of these mounds in a non-destructive way. They found that two castes of termite workers continually build pellets of wet mud. Other castes of workers then cement these “bricks” into walls using liquids that they secrete from the body. The wetness of the mud allows the suspended granules of mud to settle into any cracks in the walls that need repair, and the termite-spit then makes it proof against the hard monsoon of this part of India. Another paper led me to believe that the two meter tall termite citadels could be several hundred years old.

But which termite made these mounds? I’m as sure as I can be, without a photo of a termite, that they are made by Odontotermes obesus. I wish this common forest termite in had an easier name. This is the species which builds these tall conical mounds with flutes which look like Gaudi could have dreamt them up. But I’d seen and photographed other shapes too. Not knowing enough about termites, I’d assumed that they were merely citadels in the early stages of construction. But apparently not. Very often, the shape of a mound tells you with certainty which species built it. But Chhotani, in his 45 year old gem of a paper on the termites of Kanha NP tells us of multiple species which can be found in the mounds and fungus gardens of O. obesus. And more interestingly, he describes four different shapes of mounds, all of which seem to be built by O. obesus. With this observation he speculates that when there are more detailed studies one would find that what we call a single species now will be resolved into multiple species, each one building a mound of a given shape. Unfortunately, the study of termites in India is in its infancy. Even a paper from five years ago, which claims that there are 286 species of termites in India, making up 10% of the world’s termite biodiversity, added six new species. I was not surprised that no one has performed a gene profile of O. obesus from Kanha to check Chhotani’s conjecture. So we don’t yet know whether we can really tell the species of a termite from the shape of its mound. There are so many angles to termite life, so many loose ends in their story, that one really has to look at several pictures to piece them into one view of these shapers of jungle landscapes.

Chital

We crossed the last river bed on the way back from Bijrani range in Corbett. This was goodbye. We stopped to see a Woolly-necked stork (Ciconia episcopus), our last addition to the trip’s list of birds. A family of chital (Axis axis) was grazing between the pebbles at the bottom of the stream. A healthy buck (the featured photo), a doe, and two fawns (photo below) ranged slowly over the stones, picking delicately at small shoots. Strange that they would venture here for such slim picking; they must find these leaves delicious.

Chital lie in a genus of their own, Axis, the last remnants of a five million years old twig on the tree of life. Fossil Axis are found from Iran eastwards to Southeast Asia. They are most closely related to the Barasingha (Rucervus duvaucelii, the swamp deer). Once these were common in the Dhikala range, north of this river. But when its homeland was inundated in the 1960s by the floodwaters gathered behind a dam in the neighbourhood, they went locally extinct. The Chital are now only found in India; a landscape with wild chital tells you definitely that it was taken in India. When they become extinct, a five million year old story will come to an end.

Science da kamaal! Posts appear automatically while I travel off net.

Serene Saturday

Sometime the jungle is peaceful and quiet. The trail broke out from thickets into an open meadow. It was early morning. A golden sun. A small herd of chital (Axis axis, also called spotted deer) grazed in front of us. A sambar (Rusa unicolor) walked through the herd. Chital are easily spooked, but this herd did not mind us. Sambars are alert. It looked up at us briefly and went back to breakfast.

The scene before me was a very clear illustration of how these two species of deer manage to live in the same forest without conflict. The chital is largely a grazer, the sambar a browser. The chital is an under-rated ecosystem engineer. Its grazing keeps small plants from growing too high and smothering jungle seedlings before they can reach their full growth. They also keep the spaces under trees clear. A jungle looks very different from a garden gone wild because of these grazers.

This difference between the two kinds of deer is also reflected in their sizes. The small chital cannot possibly reach the lower canopy. I waited for the sambar to flick out its long tongue, as it does when it wants to reach a leaf too high even for its long neck. But this canopy hung low enough that it could just use its lips.

The little group fed peacefully. No smell or sound of a predator bothered them that morning. On a stump nearby I saw a black drongo (Dicrurus macrocercus). It is as dark as a crow, as intelligent and aggressive, and an incredibly good mimic. It is hard to get a good photo of a drongo because of its colour. I was lucky here. It sat in full sunlight for this portrait before it rushed off to its next appointment.

The bitterness of life

He thought he saw an Elephant,
That practised on a fife:
He looked again, and found it was
A letter from his wife.
‘At length I realise,’ he said,
The bitterness of Life!’

Lewis Carroll, The Mad Gardener’s Song

Jungle safaris during the weekend is a wonderful idea for Diwali, as long as it remains a pipe dream. Long back I was told that tiger spotting is impossible after the monsoon, when the grass is tall, and the trees are full of leaves. If it wasn’t for the need to use a pre-pandemic booking before it expires, I would have listened to this advise. As it is, I can confirm that this jungle lore is correct.

Tadoba National Park is not one of the larger ones, nor one known to foreign tourists, but it has specialized in producing conditions where tigers can breed. Most tigresses litter every two or three years. The jungle is full of tigers, and in the dry months before the monsoon it is very easy to spot them. The jungle is full of tigers even now. Early in our first outing we heard a Chital’s alarm call just as we passed an open grassland and entered a dense thicket. Definitely a tiger. A herd of the deer bounded across the road. The alarm calls passed from one animal to another, and then stopped. The tiger had hunkered down. We backtracked to a little stream.

The jungle was still. We could hear the whistling of the wind in the leaves. Then a tiny rustle. A splash. Tiger? No. Peering through the trees we saw a Chital (Axis axis, a spotted deer). It crossed the stream. An older male followed it cautiously. They must have been the last lookouts. Only a deer! Beautiful, but not a tiger. The jungle can disappoint. But even in that disappointment it is enchanting.

The big misses

After all that driving around inside Pench National Park, there were still some major species of mammals that we missed seeing. One of the closest calls was a leopard. We heard a cheetal’s alarm call and then saw the deer. We heard a langur’s alarm call very soon after. Then nothing.

The cheetal was still alert, looking in the direction where it had just sensed the predator. You can see its tail mid-quiver in the featured photo. One movement from the hidden beast and it would go up, sending out a white flash of an alarm signal as it made an alarm call again. But nothing happened. We waited for more than half an hour, and then lost our patience. We weaved our way past the other waiting jeeps. Later, in the hotel, we heard that a minute after we left, the leopard had been sighted. That’s luck for you.

Dusk had fallen. We drove to a nearby water body, and saw nothing there. Later we heard that we had missed a shy two-year old tiger cub which was lying in the water where we went, and moved off as soon as a jeep came by. This happened as we waited for the leopard!

Wild boar spooked while crossing a road in Pench National Park

We did not exactly miss seeing wild boars. I managed to take the blurred photo which you can see above. These were part of a sounder which were crossing the road. They got spooked while crossing, and the rest of the group scuttled back into the undergrowth. In Pench wild board come out in such bad light.

We never saw a sloth bear, although there are many in Pench. The only reasonable view I’ve had of these bad tempered creatures was a few years back in Tadoba Tiger Reserve. One of them was demolishing a termite mound behind a copse of trees. I could see it between the trees. The one time I took photos of a sloth bear and its two cubs, they were running away across a meadow well after sunset. A lot of fiddling with the image could give me a recognizable picture.

Another wide miss was the Indian wolf, which apparently had made a minor comeback in this area. We never heard reports of anyone seeing them in the time that we were in Pench. The deer called the Barasingha is in the official checklist, but none of the guides said they had seen one. One of them was quite categorical that there were none here, “Go to Kanha,” he said.

A close miss was a sighting of wild dogs. We kept running into jeeps whose passengers would say, “We saw a pack just minutes back. I’m sure they’ll be back if you wait here.”. They never came back. The jungle is a chancy thing. You can be sure of seeing trees. Everything else is an extra.

Alarums and excursions

If you spend a day in one of the Project Tiger national parks, you may or may not see a tiger, but the one thing that you will learn about are alarm calls. Tourists like us move along designated tracks on a jeep inside the forest. Tigers seldom cross these paths. So the best way to find out whether a tiger is nearby is to listen to the jungle.

Wary cheetal and langurs at a waterhole in Pench National Park

Of the three animals which issue alarm calls, the spotted deer Cheetal (Axis axis) and the gray langur (Semnopithecus entellus) can be seen in the photo above, and the sambar deer (Rusa unicolor) is in the featured photo. The cheetal thrive in Pench National Park. They are easily spooked. Sometimes you see a herd grazing near a track, looking up at you warily as you pass. But very often you see them already running. A naturalist once told me that this is a good sign, because it shows that they are not habituated to humans. Cheetal alarm calls are the first thing you hear when a leopard or tiger is sighted. They may soon be followed by the alarm call of langurs. Usually, when you hear this, your guide will drop everything else and rush towards the sound. Since the calls carry easily in the jungle, you will find that there are several jeeps which arrive at the source of the calls.

Sambar wade into a waterhole with extreme caution in Pench National Park

Tiger spotting requires patience and persistence. Sometimes the calls stop, and you do not know whether that is because the predator has stopped moving, or because it was a false alarm. The lore amongst guides is that cheetal calls could be false alarms sometimes, but the alarm call sounded by sambar deer is always correct. I saw sambar approaching water holes on two occasions. Both times they were so cautious that it was a wonder. The featured photo shows a lone sambar moving between trees at the edge of a clearing around a waterhole. It spent almost twenty minutes walking a distance of about a hundred meters. The second time I saw a group coming to a large pond. There were wary groups of monkeys drinking water, taking turns to keep watch as the rest of the group drank. A couple of spotted deer were also drinking water (see photo above). They were quiveringly tense as they drank, but they walked to the water very quickly, drank, and walked away again.

The sambar are different, they took a long time to approach the water. Then after drinking, they waded into the water (photo above). Even inside the water they were extremely cautious: scanning their surroundings with every step they took. The two scouts were soon joined by others, including young. Their coats were matted, as if they were already wet. Sambar like to wade, but they were so wary that they stood in knee-deep water until the light began to fade and we were forced to leave.

From the difference in behaviour that I saw, I could believe our guide when he said that a sambar’s alarm call is always correct.

Adaptation

Cheetal grazing on fallen leaves, Bhitarkanika National Park, Odisha

One of the most striking things about wild animals is how easily they adapt to circumstances; a fancy term for this is behavioural plasticity. When I saw a group of Cheetal, apparently grazing in the mud next to the tidal creek, I was a little surprised. These animals are grazers, mostly dependent on grass. But the individuals I saw were eating fallen mangrove leaves. You can see them feeding in the photo alongside. In the featured photo you can see its whole body aligned along the tide line where fallen leaves have gathered. The strong reliance on a leafy diet struck me as an adaptation.

Another odd fact was that there were so many Cheetal near brackish water. These deer drink a lot of water, and I could not imagine them drinking sea water. It gradually dawned on me that there must be fresh water inland. Amar, our boatman, and Bijaya, our guide for the day, told us about ponds and wells which give sweet water. Around these there are also grassy meadows where we saw some deer.

We also saw small bands of rhesus monkeys on the muddy banks of creeks. Strangely, they seemed to be grazing in the mud. Bijaya said they were eating grass. Possibly, because they were certainly not picking up fallen leaves. I never came across them inside the forest, so I don’t know what fruits they eat. Mangrove fruits are unlikely fare for monkeys, but maybe they have adapted. Animal behaviour is so plastic that every niche yields delightful surprises.

Spotting deer

Chital is always associated with the following bad joke in my mind: “When is a spotted deer spotted? Only after you spot it, of course.” In fact it is born spotted, as you can see from the photo of the very young fawn below.

A very young cheetal fawn

The jungles of Ranthambore resonated with the agonized call of Chital that we came to recognize as the male’s rutting call. All the adult and adolescent males sported full grown antlers. Interestingly, these fall off and are regrown every year. There were also a number of young and year-old fawns in all the herds that we saw. The chital can mate all through the year, so the spread in ages was not unusual.

Sparring adolescent cheetals in Ranthambore

We had a grand view of two adolescent male Chital sparring while the dominant male of the herd calmly browsed in the background. The fight did not look serious; the two pushed at each other, and then broke away to continue to browse. I’ve never seen Chital badly damaged in a fight, and this is the usual end to a bout.

The previous day we had seen a Chital carcass. It had been brought down by a leopard, which came back several times to feed. The park is full of Chital, so it is not surprising that here this is the main prey for both leopards and tigers.