after which the vegetation gradually changed into a distinctive, relatively low-stature Nipa-Pandanus-Metroxylon (Sagu) community, extending all the way up to the base of the foothills.
We continued on until we are surrounded by thick, dense jungle,  and trees several tens of meters high bearing down on us.
At this point the river gradually narrowed and rapidly decreased in depth but, at least at high tide, was still surprisingly navigable. Immediately adjacent to the river was secondary lowland forest, testimony to the long history of human use, ongoing small-scale gardening, and some minor, now apparently ceased, commercial timber extraction.

As we had to wait for high tide to be able to cross a shallow river bend, our guides took us for a walk inside the forest.
Walking uphill we soon entered primary forest which extended all the way to a high point of approximately 230 m. We were on the top of the hill but unable to see any distance as we were enveloped in thick vegetation.

Back on the boat, we travelled further upstream and began to appreciate that river cruising provides a great platform for observation in what would otherwise be near impenetrable jungle.

Yonas, told us that crocodiles are still common along the Gam River and we repeatedly glimpsed a single individual submerging near its preferred roost.

Bird of Paradise

Like and Iwein monitored birds visually and aurally, from time to time pointing out some of the more interesting species. They also broadcast pre-recorded vocalisations of expected or most-wanted species in order to maximise the likelihood of detection. More than a sighting, it is the signature of a bird chirp that allow a reliable identification.
King Bird of Paradise,  Cicinnurus regius,  and Lesser Bird of Paradise, Paradisea minor,  were calling continually in these foothills but the highlight of our trip undoubtedly was the sighting of a solitary Pesquet’s Parrot, Psittrichas fulgidus, flying high across the river towards a karstic limestone ridge, early morning on January 5.