Well, the title of this short post is a bit of an exaggeration.
As you can see, Olive-spotted Hummingbird is not a very flashy member of the second most diverse family of birds in the world. Most birds with the word "olive" in their names aren't. Despite that, this was one of the highlights of this morning's birding on Yanamono Island, a major river island in the Amazon River opposite Explorama Lodge. There are a number of birds known only or primarily from such islands, and this hummer is one of them. The ranges of these birds, among which we also saw Zimmer's Woodcreeper, Red-and-white Spinetail, and Plain-breasted Piculet, appear not as amorphous blobs of color on the maps in your field guide, but rather are long squiggles that follow the Amazon and its major drainages, such as the Ucayali, Napo, and Madeira. If you haven't been to these areas, you haven't seen these birds.
This afternoon we rode the fast boat down the Amazon to its junction with the Napo, then went up that river to ExplorNapo lodge (and the ACTS field station) for the next five nights. Tomorrow we'll bird another island near here, looking for more specialties such as Parker's Spinetail and Riverside Tyrant.
Here we are about to board our boat from Yanamono Island. It's been overcast and cool from an unusually strong cold front. The low this morning was 62°F, the high only 68° today, close to an all-time record low for the normally steamy heart of the Amazon Basin.