Wednesday, August 13

Location: Cocha Salvador, Manu Reserve, Peru

Today's weather: 27°C.

Up at 6am. After a quick breakfast, I washed my clothes in the river then left them draped over a branch by the riverbank. Without shade it gets very hot and sunny by the river – so I was sure that my clothes would dry very quickly. I'd originally planned to dry my clothes on top of my tent which was pitched a little way into the forest, but Tino had pointed out that things don't dry so well within the cover of the jungle.

We crossed the river in the canoe and trekked through the rainforest to the bank of another small oxbow lake. Here there was another family of giant otters, and a small catamaran (really just two canoes joined together with a small platform) from which we would try to see them. Alliu and Rick paddled us into the centre of the lake (I then took over paddling from Rick for a while, then Tino took over). We paddled around the lake looking at the diverse birdlife – hawks, herons, vultures, kingfishers, hoatzins and orephendalas. We paddled passed a dead tree which had been taken over by a group of birds called yellow-rumped cassigi. We must have disturbed them because about 30 or 40 birds suddenly flew out of the nest as we passed by. The most impressive sight was watching an emerald-green kingfisher in a nearby branch trying to swallow a fish that it had caught. The fish was almost as big as the bird, itself – but somehow the kingfisher managed to eat it in a few gulps. Through our binoculars it appeared as if the fish was still wriggling about inside the kingfisher's stomach – but the kingfisher shook itself several times trying to rid itself of these final few after-effects.

Within the lake, we saw caimans swimming across with just the noses protruding above the lake surface, and several turtles resting in the sun of logs close to the bank. But the turtles were forced to share the log with a group of black cormorants attempting to dry themselves after diving for fish – their wings were outstretched to maximise the sun they received. Looking above, I saw a yellow-headed vulture circling over some nearby trees, a toucan, and several macaws also flying overhead. This was truly a wonderful place for wildlife. But we still didn't see any otters. Tino guessed that some of the other tourist groups had been rough – attempting to follow the otters too closely and forcing them to hide in the nearby forest or at another nearby lake for some peace and quiet. As a biologist, Tino had spent six months living at the lake studying the otters. He knew them well, and was concerned at the recent actions of some inexperienced tour guides who "chased" the otters in the catamaran to ensure thrills for the tourists. But otters are very sensitive about their environment – the best and least damaging strategy, according to Tino, was for the groups to keep their distance from the otters and just to watch them quietly (through binoculars for a really good view). This way, the otters could continue to live as normal and tourists would actually have a better chance of seeing them because the otters wouldn't be hiding. At the moment the only qualification that that many tour companies require for their guides is the ability to speak English – and only a few companies have policies regarding their treatment of the animals in the park.

We stopped paddling for a while, and rested while munching on a snack. Some NZ/Australia jokes were exchanged between Rick and myself. Tino told us that within Peru, the people of Arequipa (a Peruvian city) are the subject for most jokes. Arequipa is a very beautiful location – but, Tino said, the people just seem to be a little bit different from elsewhere in Peru. Arequipans are very proud, so the rest of the country enjoys having fun at their expense – and most Peruvian football teams make a point of humiliating them in soccer games.

After our time spent out on the lake, we trekked back through the forest for the short walk back to the canoe. Our canoe then took us back across the river to our camp. We had lunch and spent a few hours just relaxing, writing notes, or reading. I grabbed one of the mattresses and propped it up against the tree like a chair. I was very comfortable. The only problem was the sandflies and other biting insects around me – but all was taken care of with an application of insect repellent. All around me was luxuriant green rainforest, with brown leaf-litter that crunched underfoot like walking on cornflakes. The air was full of the sounds of crickets, cicadas, and other insects. Everything was perfect – although I'd probably have been prepared to kill for some decent ice-cream.

Having spent a few hours relaxing, Tino roused us to get back into the canoe once more and to go back into the rainforest around the lake. Everyone had gone to sleep after lunch – I heard Paula yell in the direction of Rick's tent: "Rick! Get up and STOP snoring!" in her strong Argentinean accent. I just smiled.

Trekking through the rainforest once more – Tino explained a little about the rainforest ecology. He started by showing us the biggest trees, notably the Saber trees. These trees grew upwards towards the light – they got very high and eventually formed the rainforest canopy. Because they were so big they needed strong roots to support and nourish them. This partly explained the huge buttresses supporting the biggest trees. The good soil wasn't very deep, so that the roots only went down a few metres although they extended out in the area around the tree for 50 to 100 metres.

Tino then moved on to show us the "strangler" trees. The seeds for these trees were often carried along by birds and other animals who would deposit them in the top-most branches of another big tree. The "strangler" would latch onto its host tree. Because the "strangler" starts growing in the top of another tree (close to the light) it grows downwards – with branches the creep down and wrap around the trunk of its host. Eventually, after about 30 years, the "strangler" reaches the ground – and its branches just begin to get thicker. The "strangler's" branches begin to constrict the host tree, preventing it from growing any more, and eventually kill the host although this might take another 30 years. Once the host is dead, its wood gets eaten away by animals and decomposes – leaving only the "strangler" which has a big hollow on the inside where the old tree used to be. These hollows can be big enough for people to walk inside, as we did for one "strangler" that we found. Some trees avoid "stranglers" by having bark that regularly peels off, so that the "stranglers" can never get a decent hold.

The third set of plants that Tino showed us were mangroves. These had roots that were visible half-way down the trunk. The roots were like this so that they could absorb nitrogen from the atmosphere. The were also used to collect minerals and other nutrients from the riverwater which flows around the tree during the wet season when the forest is flooded. Tino also pointed out palm trees (one type with a bulge in the centre of its trunk is a favourite nesting place for macaws), fruits, and a variety of other plants.

We didn't just see trees. Wildlife that we saw during our walk included brown capuchin monkeys playing in the wild sugarcane next to the river, and spider monkeys swinging through the trees of the forest canopy. According to Tino, spider monkeys were the biggest of all the American monkeys (I'd previously thought that Howler monkeys were bigger). They have a very long tail which they use like an extra limb for grabbing onto branches – and when swinging through the treetops of the Amazon rainforest they have no other equal. One of the spider monkeys was a female who had a small baby clinging to her back as she moved through the treetops.

We had our ritual swim/wash in the river, and returned for dinner back at the camp. After dinner we waited for it to get dark then went for a torchlight walk in the forest. We hoped to find some Owl monkeys. These are the world's only nocturnal monkeys – they have huge eyes like owls, and are well-suited to nightime foraging. Our walk took about an hour – and because it was very dark, we had to make sure to stick together in a group. Getting lost in the rainforest at night wasn't something that I wanted to experience. At one point we stopped, turned off our torches, and listened to the noises of the insects and other nightime animals – it was wonderful. Tino showed us a tree with fireants, but warned us not to touch because their bites can sting for up to 24 hours. Nearby was another tree with a column of leafcutter ants scurrying down the trunk carrying chunks of green leaves like green sails on their backs. The leafcutter ants don't actually eat the leaves – instead they take them back to their nest where the leaves are used to cultivate a special fungus. It is the fungus which provides the ants' food.

Unfortunately, we didn't find the monkeys – but we did hear them calling out and scampering in the treetops above. By the time we reached the camp everyone seemed to be feeling very tired due to our long activities for the day. We chatted a little, but then headed off for bed. The forest soon echoed to the sound of Rick's snoring – and somewhere nearby, I thought, there were bound to be some Owl monkeys complaining about the noise.