Almost the first thing I saw in Hollongapar Gibbon Sanctuary was an abandoned railway station. I’ve already written about the railway line which fragments the sanctuary and still has heavy train traffic. Because of my new-found interest in abandoned colonial-era structures, I made a beeline for it even as my companions were stretching their legs. Tall trees rose behind it. Grass and little herbs had taken root on the roof, but the sturdy brick structure was reasonably intact from inside.

The paint was peeling and the doors had disappeared, but the plasterwork inside was relatively undamaged. I could only see two or three places where large chunks of plaster had fallen away. The floor was pretty undamaged, although it was strewn with trash. It was interesting to stand inside and look out at the rain forest and the single railway track which passed by. It is not hard to reel back time in your head to see a slow train come to a halt, while waiting passengers streamed out of the room to board it.

The long cement bench against the wall with windows was also pretty serviceable. At a pinch one could think of dusting it off and settling down for the night. One of the windows was missing its lattice work, but this would be hardly worse than the doorways without doors. The walls were typical Indian Railways dado: darker colour below shoulder height, and light paint above.

Even so far away from civilization, the wall has become a canvas, even a palimpsest, for Amit, Amar, Samrit, Deep, and a few other men. There are loves that dare not speak their names: B+B and D+S were par for the course. I was more intrigued by L+G+D and Amit+3. Something different is developing in these places clearly.

This was clearly the waiting room. The ticket office was next door: inside the massive prefab container. The counter was still open. The corrugated metal sheets still held their paint; there was no obvious sign of corrosion. Even the net over the window did not look badly rusted. There must have been a little platform of wood in front of the window. Part of the support is still there, but the plank above it has been taken away.

I peered in through the window into the large hollow space beyond. Wouldn’t it be wonderful for a photographic exhibition on wildlife? I thought of hanging my photos here, with bright LEDs spotlighting each. I suppose the space still belongs to the Railways, and if I want to have an exhibition here, I’ll have to apply to them.

A birdwing butterfly

As we walked through the Hollongapar sanctuary, I saw several of the common birdwings (Troides helena). These are distinctive large black and yellow butterflies which usually fly fairly high but below the canopy of the forest. I’d first seen them several years back somewhat further south, in Tripura. Its range continues south and east from Nepal into the Indonesian archipelago. It is so distinctive, that I had no trouble recalling its name. I had seen a mating dance once, but this time I saw them only singly.

T. helena gets its colour from pigments, unlike many common butterflies in which diffraction of light plays a part. The strong colour advertises the fact that it is poisonous. Usually in butterflies most of the eating is done by the caterpillar (larva), so that the adult (imago) can spend its time flitting from flower to partner and so on. The poison is obtained by the larva from some of its food plants. I was surprised to find that it is fairly long-lived for a butterfly: the larval stage lasts for three to four weeks, then it pupates for about two weeks, and the adult can live as long as six weeks.

All morning we’d seen these butterflies. After lunch near the forest guest house, I walked back along one of the forest paths to see whether I could spot any more butterflies. The Lotus stayed behind near the guest house. When I returned disgruntled from a failed search, she had the wonderful shot which you see as the featured photo. This individual looks like a male. What a wonderful piece of serendipity, and what a lovely picture. The Lotus was kind enough to give me the photo for my use in this post; if you like it, please leave a note which I can pass on.

Bad design award

A railway line cuts through the Hollongapar Gibbon sanctuary. The gibbon census of 2008 recorded 3 families of Hoolock gibbons in the smaller part of the sanctuary and 26 in the larger part. Hoolocks never descend to the ground, preferring to swing from tree to tree in the middle and upper canopy. As you can see from the featured photo, the railway line creates an impassable barrier to these apes.

Hoolock gibbons (Hoolock hoolock) live up to 35 years, have a single baby every two or three years, and mature in 6 years. So, on the average, the number of families doubles in three years. According to an expert who walked us through the forest, there is no overcrowding yet. So the number of families may have tripled in the last 10 years since the census. This means that the population in the smaller section of the sanctuary is in danger of inbreeding.

Recognizing this, the forest department created what they thought was a gibbon bridge. That’s the strange structure which you can see in the photo, crossing the tracks at the level of the upper canopy. We were told that no gibbon has ever used this. When we followed a family of gibbons through the forest we realized that they never walked on branches. For over half an hour we saw them swing and jump from one branch to another. The bridge completely neglects this simple observation. If you know of a bad design award for wildlife conservation, I nominate this bridge.

Running through a forest

When we were young, my cousins and I would occasionally rumpus through the house and be brought up short by our grandmother calling us “A bunch of oolluks.” When we asked her what an oolluk is, she would clam up and say “You haven’t seen one.” Years later, when I first saw a small family of Hoolock gibbons hooting and swinging through trees, I knew that I’d finally found the referent.

The Western Hoolock Gibbon (Hoolock hoolock) is a creature of habits. It wakes late, breakfasts at about 9 in the morning, plucking tasty leaves and fruits while swinging through its home range. Hoolocks live in nuclear families, papa and mama with at most three children. They have one child at a time, and when children mature at the age of six or seven they leave their parents and younger children to find their own true love and settle down. We saw a family of four: one infant, one boisterous child, and the parents. The featured photo shows the mother with child. The child’s fur will turn dark after it is six months old.

In a year or so it will look like its sibling (photo above) running in loose circles around its parents and perhaps getting into tight spots like the older sibling. We saw this juvenile come too close to the nest of a pair of lesser racquet-tailed drongos (Dicrurus remifer), and be mobbed by the pair. Drongos are great imitators, and we heard them imitating the call of a fish eagle when trying to drive the gibbon away. They succeeded, perhaps by just being sufficient nuisance rather than by being scary.

We’d woken at an unearthly hour to drive 60 kilometers across bad roads to reach the Hollongapar Gibbon Sanctuary, where we met an expert to guide us through the forest. When we first sighted the Hoolock family, the parents were seated comfortably in the canopy, facing each other just like a couple at home (photo above). The male is very dark in colour, whereas the female has a buff coat; but they are very similar in size. The white eyebrows of the male get extended to a nearly complete circle of white around the face of the female. Their calls were loud and elaborate, and are meant to advertise their presence. They were not shy, and largely ignored us.

The IUCN red list classes H. hoolock as endangered because of enormous population losses: halving every three generations for the last couple of decades. While this is partly due to hunting, most of the reduction is due to loss of habitat as forests get cleared for tea and agriculture. Anecdotal evidence from the Hollangapar sanctuary says that locally the population is growing. We will know when the results of the census of 2015 are published, and can be compared with the result of the old census of 2008.

Gibbons move very fast through the canopy, swinging from branch to branch. As you can see from the photos, their load bearing limbs are the arms, and they seldom put their whole weight on their legs, using them mainly for balance. We ran stumbling through the rain-forest below them, trying to avoid falling into hollows or getting entangled in vines. Once I had to use an arm to swing around a tree-trunk, and it was only later that I noticed the interesting reversal in the use of limbs between me and the gibbons. When they quietened down to eat something it was easy to lose them in the gloom below the canopy. Then one could tell their position only by the slow fall of dry leaves from a disturbed branch. My spectacles misted up continuously, so a lot of the photography was guesswork. I was happy that I’d spent the previous year getting back in shape; following the Hoolock family through the rain-forest would have been difficult otherwise.

Dead leaves

I spent all of yesterday traveling; first a few hours by car, and then another few hours flying across the continental plate of India. Half a day cocooned in the dead space which surrounds air travelers is enough to create a distance between the fresh memories of the previous night and the next morning. The fact that I walked through a pristine rain forest all day long is a distant whisper from my memory.

Three days in the forest, and two days of travel bracketing that brief stay makes for a fairly long trip. Deep inside the forest you come across giant Hollongapar trees, some of which are over 50 meters tall. In the middle of the dense forest these immense trees seem to disappear through the canopy into the invisible sky. The dense undergrowth restricts your vision to a couple of meters around you. Apart from the awe-inspiring trunks of tall trees, all you can see are leaves and more leaves.

With my vision so restricted, I decided to concentrate on photos of dead leaves, and found that there are so many different ways that leaves can die! The Family asked me, “How old are these forests?” My first answer was that they must be a few hundred years old. But then I had second thoughts. Many of the species that we see have evolved within this ecosystem. Since some of these species are tens of millions of years old, the rain-forests must have been there at least that long. The few square kilometers of fragmented forests that we saw could well be the remains of a forest which has survived the ice ages. From all that we know, rain-forests have survived geological ages of radical warming and cooling. Their rapid decline could well be due to one particular animal: Homo sapiens.