Near Ilha do Mutum (6° 42' S, 60° 26½' W)
Mutum Logging Road (left bank)
Tuesday, August 4th: We got an early start, with breakfast at 4am. The idea was to do a bit of nightbirding on the shore near Mutum. We started with a roosting Striped Woodcreeper as we came ashore. We then heard (Southern) Tawny-bellied Screech-Owl (heard). A Spix's Guan was in a tree. Finally, we called in a Long-tailed Potoo.
As it got light, we started to find other birds. We had been hearing them, and eventually saw a Screaming Piha overhead. A large tree had a number of both Channel-billed and White-throated Toucans. We soon added Rufous-faced Antbird. Both Golden-winged Parakeets and an single Blue-headed Parrot flew over. At this spot the trail had some dry quicksand. As we birded, our feet would sink in an inch or two, so we had to keep finding new places to stand. Later, we tracked down a Yellow-margined Flycatcher. This was followed by a Black-tailed Trogon. A Rufous-tailed Flatbill was spotted high overhead. Fortunately, its rufous tail and wide bill allowed us to identify it. At some point this morning we also heard Prince Bernard's Titi-Monkey this morning.
The trail was blocked, and we returned to the trailhead where we found a pair of Blue-and-yellow Macaws in a palm tree. An alternative trail (and some trail work by the crew) got us around the blockage. We added Sulphury Flycatcher and Black-faced Dacnis. A Snethlage's Tody-Tyrant was in the same area, as was a Gould's Toucanet.
I had not had sufficient sleep recently. I think the 2 hours on Friday finally caught up with me. Anyway, I could hardly stay awake, so I returned to the boat for a rest. The group continued to bird for another hour or so.
Later, we spotted a Bare-necked Fruitcrow from the upper deck as we headed upriver (south) to our afternoon birding location.
Castanheira Trail (right bank, 6° 54½' S, 60° 31' W)
In the afternoon, we birded a trail on the right bank south of the Mutum area that we dubbed the Castanheira Trail due to a number of large Brazil Nut Trees. We soon had an excellent scope view of a Great Jacamar. A Lafresnaye's Woodcreeper put in an appearance. This is part of the Buff-throated complex. It is likely that it will be further split, in which case the local birds, possibly race vicinalis, may take the name Dusky-billed Woodcreeper. Note that they do not seem closely related to the eytoni/gracilirostris group. We also found a White-winged Shrike-Tanager high overhead. By continuing to look as it moved, it was possible to see most of the bird.
About this time, Bret heard a noise on the ground. It sounded like a large mammal. We were very quiet as we looked for the source, and a Giant Anteater soon walked into view. When it finally noticed us, it gave a grunt of surprise and started heading the other way. Further along, we found Red-stained Woodpecker and Elegant Woodcreeper. Late in the day, we heard Variegated Tinamou and Variegated Antpitta. The latter had been seen singing in the area a few weeks ago, but refused to come back to its perch. As we left, we heard a Great Tinamou.
After dinner, a few of us went out in a canoe for some night birding. Highlights included the eye-shine of a Paca, a number of Spectacled Caiman, a Diving Lizard, Common Potoo (also seen near the Tumbira), Tropical Screech-Owl, and a surpise bird, Rufous Nightjar. The latter sat straight up on a branch. At first we thought it might be a potoo, but we eventually realized it was not. It took a while to properly identify it.
I ended the day with 35 bird species including 6 lifers. That brings the trip total to 165 species including 33 lifers.
Aboard Tumbira, near Castanheira Trail (6° 54½' S, 60° 31' W)