While attempting critically necessary sleep before a “big day” on May 9th, 2015, the vocalization of a Common Pauraque rang out, breaking my slumber at 03:15 a.m. The pauraque was the first of many bird species I would encounter that day. In addition to me and my three teammates, thousands of birders across the world participated in this Global Big Day event with two goals in mind: 1) to encounter as many bird species as possible within the 24 hours, and 2) to find as many endemic species (species that are specific to a certain area) to contribute to the overall worldwide species count. My team included Catherine Lindell, Ph.D., a professor at Michigan State University, Jorge Valdez, the manager of Los Amigos Biological Station, and Vania Tejada, a Peruvian student of ornithology. A big day is a rigorous race that tests one’s physical endurance, will, and most of all, skill at bird identification.
I rolled over, hoping my mind would settle, but another pauraque echoed. My backyard in the Peruvian Amazon held more than 500 species in an area the size of Central Park, and I could not extinguish the blazing thoughts of the species I would encounter that day. Would I count 200? 250?? Would I be able to find the endemic Rufous-fronted Antthrush? What about the equally range-restricted Peruvian Recurvebill?
Finally, 04:00 arrived and I allowed myself to get out of bed. I stood by the misty cliff near my cabin in the dark, and I listened. I scrutinized the silence for the next hour, but only picked up a few owls and nightjars. This was not a great start for a day that should end with more species than I’d ever recorded in my home county in Michigan. At the first hint of daylight, I headed into the bamboo thickets, where many species live that can only be found in southeast Peru and western Bolivia.
Though it was still too dark to see, the bamboo produced the expected endemic species with few exceptions. In the early morning hours, when the dark forest is illuminated by hundreds of singing birds, the strategy is to slowly creep and listen. In addition to species seen, species heard also count for the Big Day list. A single, soft “pep” is enough to count the Long-crested Pygmy-Tyrant, a bird whose name is bigger than the bird itself. Large-headed Flatbill? “Bwow bwoa!” Check! Peruvian Recurvebill? “Hyuak-ak-ak-ak-ak?” Check! I continued through the primary rainforest, which is like a gallery of wooden giants, and then river edge habitat, which is like a crammed procession of palms and powerful cicadas. In order to count the most species possible, I needed to visit the most habitat types possible. As the morning progressed, I made my way to the lower terrace forest, and finally to dense thickets and ponds in the southern end of the station’s land. Here, I cashed in on many species only found in this area, such as Wattled Jacana, Rufous-fronted Antthrush (woohoo, that was a load off my mind!) and Agami Heron. I beat it back to the station for lunch, harvesting calls from the canopy on the way – a repeating “spew” here (Slaty-capped Shrike-Vireo), a soft trill there (Pygmy Antwren).
Halfway through the day, I made a mental list of birds I still hoped to encounter. I counted 38 antbirds and a handful of hummingbird species. To fill the major holes in my list, I set off to the high terrace forest on the northern half of the property. The afternoon produced few forest birds compared to the morning; it was like pulling teeth to find even some of the most common species. The sun was beginning to set, so I dashed to a high overlook above a marshy oxbow lake, where I desperately sought my final species in the last moments of daylight. As the sun set, new species emerged; some Horned Screamers duetted, Masked Crimson Tanagers aerially pursued each other, and some hidden Rufous-sided Crakes burst into their raucous quaver. Night fell, producing the final species of the day – Long-tailed Potoo, species #282.
In the end, I logged 282 species in 18 hours of rigorous birding, a new personal record. My teammates were able to find an additional 26 species, bringing our total to 308. I was all but debilitated, physically and mentally. I was so drained after tracking down so many birds that for a second I almost thought, I wouldn’t mind not seeing a bird for a while. Regardless, I trudged into bed and attempted some critically necessary sleep, waiting for the next Common Pauraque to ring into the night.
Almost 6,000 of 10,000 bird species were recorded worldwide that day among 12,000 participants. Peru was the #1 country in the world for species with almost 1,200, and 308 was one of the highest species counts recorded for Peru.