As we progressed further away from the camp (and from the road from which most interlopers are likely to have travelled) the vegetation became wilder. We journeyed through a still pool of water for nearly a kilometre. Then I notice up ahead that our way was almost completely blocked by rocks jutting out of the water. A few of these were full grown islands on which were small trees. I noticed many birds took up perches here, no doubt hoping they were safe from jungle predators. As we got closer, I realised that the rocks did not cover the whole riverbed, nor even cause any cascades, the water moved smoothly through several well defined channels. Once or twice we could see submerged rocks that slightly scraped the base of our canoe, and I could imagine in the dry season navigating by canoe would be much more difficult. And by seeing the exposed areas around us, I could also see that in the main wet season the river level could go much higher, and again the currents might stop easy navigation.
As we followed the twists and turns of the river through these rocks we became aware of a lot of bashing in the trees to our right. Monkeys were bouncing from branch to branch; eventually we realised they were tracking us from the bank, rushing along for a few seconds then peering out at us to see what our reaction was.
We dropped down below the rocks in to another large still pool in the river; it bent gently round the left and opened up into a long strait. The sky had all but cleared, just the odd small cumulus cloud peppering the horizon, and the water reflected it like a mirror. With the exception of a few slight ripples, and the odd ring created by a gulping fish, the only break was way in the distance. Through binoculars I could see two brownish lumps above the water edge – maybe more rocks, but then I noticed something flickering above these rocks; their ears. The rocks were moving too and causing a little ring of disturbance around them. We were fast approaching a herd of hippos. As we got closer it was obvious these creatures had been observing us since we turned into the strait but they were calm about it; they just watched, occasionally flicked flies with their ears and apart from their eyes and forehead, nothing else of them could be seen. The warden was quite happy to lead us close to them, on the shore furthest away from the herd. As we drew parallel we were aware it was not just two animals, more heads appeared from below the water also not too concerned with us. The first animal we had spotted still intently watched us, and was well positioned between us and the rest of the herd. It was fairly obvious this was the dominant bull protecting his family.