Volcán El Reventador is one of the more active volcanoes in Ecuador, most recently blowing its top in 2002 and spewing ash all over Quito, which is located about 100km away. The resulting lava flow decimated the subtropical forest surrounding the resurgent summit cone, and even more recent lava flows have created a strangely beautiful landscape with layers of igneous rock, lichens, and moss, encircling small islands of woodland and forest. Recklessly, Griffin and I summitted the peak several years ago, camping at the edge of the scene of destruction and dashing up and down the cone in the early morning. As the adventure is one of the most memorable I've had here, when Mark Thurber, author of Climbing and Hiking in Ecuador, proposed a similar excursion, I jumped at the chance to revisit the area. 
After a difficult drive in darkness from Quito to the small town of El Reventador, four hours away, and a restless night at a roadside hotel, we awoke to clear skies over the normally rainy eastern slope. I spent an hour birding before breakfast, photographing the Magpie and Silver-Beaked Tanagers with some success, until I noticed a pair of parrots perched high in a tree on the other side of a stream adjacent to the hotel. Scaly-Naped Amazons aren't often seen perched out in the open, so I took out the scope and lined them up for some satisfying looks. As soon as the sun rose over the opposite ridge and shone fully on them, they took flight, brilliantly green in the rich morning light.
At the outset of our expedition, we walked along one of the oil pipelines in the area until we intersected paths with the trail. As our party of five included some rather slow hikers, I had ample time to sift the forest along the trail for birds, finding the local White-Tailed Hillstar at a recently fallen tree that was still in bloom; this dark-colored but striking hummingbird is on the target list of every hardcore birder who visits Ecuador, showing significant variation on the eastern and western slopes. At several points along the trail I also heard the White-Bellied Antpitta calling away, close enough at one spot for me to break out the playback and see if I could reel it in. There was some decent mixed flock activity along the trail as well; in fact, I was bombarded by close to two hundred birds as they sped past me through a clearing, moving so quickly that I only observed a small handful, including the Flame-Faced and Beryl-Spangled Tanagers, Common Bush-Tanager, and Bluish Flowerpiercer. 
After four hours of sweaty climbing, we finally burst through the forest and out into the open area created by the most recent lava flow in 2002. The summit cone stood impressively in the distance as we surveyed the larger horseshoe-shaped crater, its massive walls scorched in places and verdant in others. This scrubby open area was remarkably devoid of interesting birds, and I only noted the Rufous-Collared Sparrow, Sparkling and Green Violetears, and Band-Tailed Pigeon as we walked closer to the base of the summit cone. Stumbling around this broken and steaming landscape, I was blown away to notice that another huge lava flow had occurred in the two years since I was last here, streaming down the western side of the cone and spilling over previous flows. Trained as a geologist, Mark was particularly interested in deciphering the volcanic activity while Aimee was fixated on the botanical details of the environment, noting how the different mosses and lichens were breaking down the igneous rock into soil.
I had high hopes for birding the trail on the way back that afternoon, but activity was unusually low. While the ubiquitous Cinnamon Flycatcher was calling and sallying about as usual, I noted little else except for the Masked Trogon in a more mature patch of forest. Tantalizingly, at one point I heard two Black-Billed Mountain-Toucans calling in the distance, an eastern slope specialty that's frustrated me on more than one occasion. We returned at dusk to the hotel, then, having seen relatively few birds but having witnessed one of Ecuador's more impressive geological features.Notable birds seen: Scaly-Naped Amazon, White-Tailed Hillstar, Inca Jay, Masked Trogon, Spotted Barbtail, Streak-Necked Flycatcher, Handsome Flycatcher, Cinnamon Flycatcher, Black Phoebe, Andean Solitaire, Blackburnian Warbler, Three-Striped Warbler, Bluish Flowerpiercer, Flame-Faced Tanager, Orange-Eared Tangaer, Beryl-Spangled Tanager, Saffron-Crowned Tanager, Magpie Tanager, Silver-Beaked Tanager, Subtropical Cacique.