Wearing boxers and nothing else, I step warily down the steps into the murky waters of a large tank, shivering on this crisp January evening. Satyan, toweling off, tells me the murkiness is actually nothing to worry about, but I should be careful of one step, underwater, that is broken. I find that one with my toes and gingerly inch forward ...

... suddenly I am slipping and falling and I land heavily on my butt, in the water, on the broken step. Takes a few seconds to realise nothing more than my ego is bruised. No, there is this sharp pain in my left pinky finger, and when I look I wish I hadn’t. The nail has a crack down the middle, and under it is a layer of black dirt, forced in there when my hand went out to break the fall.

And I think: here’s a nice coda to two days of birdwatching.

They have been a largely silent two days, the long but lovely hours punctuated only by shouts of “kingfisher!” or “Greater, ekta!”, or “Lesser, ekta!” and the like. Well, not quite only those sounds, for following them came the whirring shutter clicks of five or six cameras, and following them came excited exclamations like “Aaah, black-capped!”

Greater and Lesser Egrets, that is, almost always singly (“ekta”), and the black-capped Kingfisher. That kind of trip.

Last December, the Sundarban Tiger Reserve announced the second Sundarban Bird Festival and called for applications. I applied. Considering that about the only ornithological qualification I could claim was “I like watching birds from my balcony”, I didn't really expect to be invited. Yet I was, and later found they had selected 25 out of 70 applications. Why me?

Not that I especially wanted an answer. I was just thrilled to be going. Once the 25 of us arrived in the Sundarban, we were split into six groups. Six boats. Six different areas of the Reserve. Three days and nights we'd be on our boat, roaming the waterways in our designated area. We left the Park office that evening and I don't know about the others – Sundarban veterans some of them, it looked like – but I was flush with adrenaline, barely able to stand still.

A while afterward, utter darkness all around, I see them: Just under our prow, little flashes in the water, accompanied by small splashes. Is it light from our boat, reflected? But the flashes are too random for that, too ephemeral if you like – and there are those accompanying splashes. Next to me, Piyush says one word, “fish”, and climbs down to the lower deck.

Later, Avijit explains less laconically. The influx of sea water in these parts brings phosphorescence, he says. Some kind of fish flit through the water, lighting up the phosphor as they pass. Magical. Later, he will show me – pouring water into the river, we see the same thing. Or, he suggests, “dip your hands in, scoop up some water and let it flow out – it’s like your hands are on fire!” The joy of it all over his face, even though he has come to the Sunderban innumerable times.

Later still, we stop somewhere. On a night like this, place like this, I’d have expected a spectacular night sky. But sadly, with the light cloud cover, we can see only the few stars that poke weakly through. Still, the silence like never before more than makes up.

When I come down to my bed on the lower deck, my companions are all snoring. I lie there for a long time, thinking, strangely enough, of the young man piloting our boat. For the last few hours, he has been doing so in this blanket dark. But how? I actually asked, but all he offered me was that he never turns on his lights at night, because they interfere with navigation. That is, I had to come to terms with the idea that he was threading us through these waters purely on feel and knowledge and instinct. Left me both mildly uneasy and strangely comforted, at the same time. But as a thought to fall asleep with, I couldn’t have done better.

Wake at dawn and emerge up top to the same light cloud cover, a definite chill in the air. It’s foggy and silent, the water’s velvety – in appearance like thick slow-flowing oil or honey. Everything almost in monochromes. And this slight surprise: we are anchored smack in the middle of a broad stream. The pilot answers that question too: this way, it’s more difficult for a passing Sundarban tiger to come aboard. Note that he doesn’t say “impossible”. He says “more difficult”.

In these parts, in this habitat, the magnificent Royal Bengal Tiger has adapted to its surroundings – these animals know how to swim. Yes, swim! So I would have liked a calculation of how much safer we are at anchor in the middle rather than tethered to a stake on shore; how much safer we are, that is, in forcing a hungry tiger to have to swim to reach us rather than simply leap aboard.

There’s that tiger spectre to take in on this shivery morning, and too the realisation that we are cut off from the world. This deep in the Sundarban, there’s no signal on our phones. No way to speak to faraway loved ones. Only a couple of decades ago, this would not have been in the least unusual. But today? Mildly uneasy and strangely comforted, again. Can’t call or text, ok. But how delicious it will be to get back in touch with those faraway ones in a couple of days and have a whole load of images and impressions to offer them, instead of streaming WhatsApp photos at them nonstop as we roam!

Time to weigh anchor and move. Satyan sits in the prow, the rest of us on various perches behind, our cameras and binoculars at hand on a broad cot. Satyan it is who usually shouts the birds’ names – “Greater!” and the like – prompting the camera-wielders to swing into action, and I use that word “swing” advisedly. That’s the only way to describe how their enormous lenses are brought to bear on the target Satyan alerts us to. They swing up. Then the shutters start clicking, rapidfire. Then the camera-wielders swing the lenses back down and bring up the just-shot images on their screens, usually delighted by the results, showing them around.

Certainly I wield my camera too, but it is a far shorter lens and it doesn’t swing quite as elegantly. And I can’t get anywhere as close to the birds with it as these guys can. And anyway I don’t immediately look at my shots: I prefer to download them and browse on my laptop, later. This is not to say mine is the better way. If I had a monster lens I’d be looking at the results immediately too. But somehow the whole sequence – shout, swing, click-click-click, swing, peer, “Aaah, black-capped!”, and all in these largely grey-scale surroundings – made this birdwatching experience particularly memorable.

Grey-scale, did I say? Not the birds, though. Light-brown common sand plovers (“CSP” the shout, so common that the photographers soon stopped being tempted to shoot them), pearly-white egrets, black and white lesser adjutant storks, doves, curlews, whimbrels, herons, warblers, drongos, eagles ... many many more, and then there are the kingfishers. Several varieties, in magnificent colours, perched like watchful but hunched sentries, like flashing jewels as they fly.

I learned quickly from Satyan how to spot them, even at a distance, and even beat him to the shout a few times. I mean, I don’t think there is a bird on this planet I find unattractive, and our boat spotted some 70 different species, and all six boats accounted for over 130 species and nearly 9,000 sightings, and even so, for me the crown jewels were the kingfishers. No other avian quite matches their colour, their patience, their demeanour, their flight, their swift and precise dives and the head-twirling way they beat the life out of their prey before swallowing.

There in the Sundarban, we saw no tigers, whether swimming or trying to board. But we did see innumerable kingfishers. I have absolutely no complaints.

But yes, I hurt my pinky. Satyan called over a colleague, who brought a blade. I winced at the sight and braced for pain. But he held my finger firm and in a matter of seconds had sliced off the nail and cleaned out the dirt. Two swift, precise strokes. Could have been a kingfisher.

Dilip D’Souza’s most recent book is Roadwalker: A Few Miles on the Bharat Jodo Yatra.