Dear Readers, after the watery world of Tortuguero we headed inland to the volcanoes of the Arenal area. Mount Arenal itself was originally a huge draw for tourists – they could sit on their hotel verandahs in the evening and watch the lava trickling down. Sadly, as a live volcano ages, the crater deepens, and so no one has been able to see lava for a while. As a result, the many many hotels have had to be creative, and the one that we stayed at made a big feature of its thermal pools.

It also made a point of featuring the volcano everywhere, as in my Volcano dessert. It was only a ball of ice cream with a conical biscuit cover and some strawberry sauce, but it looked very impressive nonetheless.

We arrived after dark, but the following morning the clouds had cleared, and we saw this:

Mount Arenal now has nine separate craters (each new eruption changes the morphology of the area), and you can see how the volcano is emitting steam. Tourists are (very sensibly) not allowed to go walking up to the summit in case they get scalded to death/knocked on the head by exploding rocks/mown down in a stream of lava. Nonetheless, several tourists were killed when an unlicensed guide decided that it would be fun (and probably lucrative) to take them up for a look a few years ago. Stupidity and greed are unfortunately universal (as are generosity, responsibility and kindness, though they don’t get such extensive press).

John and I decided to go for an early morning walk around the extensive grounds of the hotel instead of risking immolation, and spotted some crested guans in one of the ornamental trees. It is always a privilege to see such wild creatures so close up. They seemed mildly curious, but kept a decent distance.

On the way back down the hill, I stopped to look at, and film, some leaf-cutter ants. They are a delight as they go about their business, harvesting great chunks of twig and leaf and taking them back into their nests. As I was filming, I sensed that I was being watched. I looked up to see an attractive young couple dressed for the spa.

‘What are they?’ asked the chap.

‘Leaf-cutter ants’, I said. ‘Do you want to know about them?’

My temptation is always to launch into a full lecture, but age has taught me that a) people are sometimes not interested and b) they often know more than I do, so I tend to be more careful than I was.

However, on this occasion, they both gave a kind of interrogatory shrug, which I interpreted as meaning ‘tell me in brief, but I am on my honeymoon you know’.

So I told them quickly about what the ants were doing, and how they grew fungus on the plant material.

‘So,’ I said with a flourish, ‘really they’re farmers!’

And then, the young man spoke up, and I was somewhat taken aback.

‘Can I ask how you know all this stuff?’ he asked.

Well. How do I know all this stuff?

‘I’m passionately interested in it, and so it just kind of sticks’, I said, with rather less eloquence than I’d have hoped. But it seemed to do the trick.

‘Good answer!’ said the chap, and then the two of them sashayed off to loaf around in the springs and no doubt drink martinis.

I do wonder about his question, though. Was he accusing me of ‘fake news?’ Did he not know how people found about stuff? Or was he just surprised that I knew about ants?

I really should have a ‘Bugwoman’ business card to hand out, to legitimize my interest in things buggy.

Lounging about in a thermal pool was not for us, however. We were off on a river trip. The nearby Rio Frio is an extremely biodiverse river, and we were going to get the chance to explore it. The boat was as usual kitted out with what seemed like garden chairs, but it had a roof (a fine feature when it can bucket down with rain with little warming) so we were delighted. Its captain, Herman, took us for a brief spin in the shallow part of the river, which was full of wood storks and a couple of roseate spoonbills. While the wood storks have fleshy, vulture-like heads and are in shades of black and dun and dirty white, the spoonsbills are cerise, a most exceptional colour. They were smaller than I expected, but at one point they started to skim the water with side to side sweeps of their bills. Mangrove swallows skimmed alongside the boat, their feathers iridescent purple and green.

We had heard howler monkeys before on the trip, but this time we had a chance to see a little group feeding. Every Costa Rican male has got the howler monkey’s call down pat, and Herman and Walter both tried to engage the heavy-set male howler in conversation. However, he was a taciturn individual and, after a few grunts, turned his attention back to food. When one of them jumped to another tree, the others thought about it for a few minutes, and then followed. Seeing these creatures free in the trees makes me regret the impoverished lives that captive monkeys live – there is no human-provided substitute that can make up for the loss of the variety and sheer scope of their wild lives.

Herman was a gentle and considerate captain, and we moved slowly and carefully from one bank to another. We came upon a group of white-faced capuchins in a date palm, and were able to approach to within ten metres. One of the monkeys looked up and bared his teeth at us in a threat display, so we came no closer. The monkey continued to dissect the tastiest morsels from the dates, and a few others became visible. They are so attentive and concentrated as they feed, their hands are so delicate and precise that they reminded me of jewellers, selecting the right stones for their pieces and then preparing them in an appropriate way. It was our only time with this species on the trip, but they are very charismatic – they are called ‘the apes of Central/South America’ and they have a intelligence which shines through in their nut-brown eyes. When you meet the eyes of one of these creatures you are definitely encountering a ‘person’, a being with thoughts, needs and a personality, not just some generic ‘monkey’. I suspect this is true of all sentient creatures, if we only took the time to look.

In the UK, you wait for a long time to see a kingfisher, but here they were everywhere, along with the elegant anhingas (a type of cormorant that swims with just its neck exposed) and a bird called a sun grebe, which is not closely related to ‘ordinary’ grebes, and which only rarely dives (unlike your standard grebe, which waits till you’ve focused your camera before disappearing for ten minutes).

And there on the bank was a very relaxed crocodile. With so many fish and birds and frogs and the occasional clumsy monkey to munch upon, no wonder s/he was grinning

But what I loved most of all was a fine view of a sloth. We’d seen a sloth before, of course, but as we rocked about on the boat and got our binoculars focused, it became clear that she was not on her own.

Can you see those tiny sloth ‘hands’ ? What a warm and cosy home for a new baby, wrapped up in his or her mother’s fur. What a heart-warming sight.

All too soon it was time to head back to the bus. A trip that took us two hours as we meandered up river took us just fifteen minutes as we cruised back. But what a ride! We were lucky to see so much, and to have such knowledgeable and sensitive guides. As we ate our rice and beans afterwards, we all agreed that it was one of the highlights of the trip.