A Cape Cod Birder in the Peruvian Amazon, Finding Species Unique and Familiar

Apr 5, 2017

A few weeks ago I got a call to fill in for a colleague leading a Mass Audubon birding cruise on the Peruvian Amazon leaving on March 24. The prospect was daunting – the field guide to the birds of Peru has the heft of an unabridged dictionary, and I had just a week to prepare. At around 1800 species, Peru is neck and neck with Columbia for most bird species of any country in the world. 

This was the big leagues. Luckily, a lot of the species only occur in the Andes mountains or at the coast, so I was really looking at only 800 species to study. No problem.


The ecological enormity of the Amazon is hard to convey. The thickly jungled drainage basin covers almost 3 million square miles, or 40% of the South American continent. The rich forests and rivers hide at least 12,000 species of trees and 2400 species of fish in addition to the well-known diversity of birds, monkeys, and cats. Holding fully one fifth of the world’s river water, the Amazon basin is so big it has two different species of freshwater dolphin, one of which is bright pink. Both were common on our cruise, though not always easy to see in the latte-colored water of the main rivers.


Starting in the isolated Amazonian city of Iquitos, which is reachable only by plane, we boarded our embarrassingly comfortable cruise ship and headed upstream on the main stem of the Amazon, then into two major tributaries, the Ucayali and Marañon Rivers. This was not roughing it. While Teddy Roosevelt lost 55 pounds and nearly died from malaria during his Amazon exploration in 1913, we were at more risk of pre-diabetic symptoms from the vast quantities of food we were consuming three times a day before retiring to our air conditioned cabins.


Up to three daily excursions in slender skiffs took us into the smaller tributaries, creeks, and oxbow lakes where the birding was best, or to small, remote villages where we met a local Shaman to learn about medicinal plants and visited a school whose location defined the term “middle of nowhere”.


The wildlife was overwhelming at times. We saw 18 species of parrots and parakeets, including 5 kinds of big macaws, plus 8 species of monkey, sloths, and fish-eating bats with two-foot wingspans. My favorite sighting may have been the tiny Pygmy Marmoset, which is the smallest monkey in the world at 5”, and an animal I’ve wanted to see since I was a little nature geek of a kid.


We had good luck finding one of the characteristic birds of the Amazon, a bizarre species known as the Hoatzin. The best way I can explain this bird to you is that it looks and acts like it just evolved from the dinosaurs yesterday, and is still trying to figure out how to be a bird. Two feet long with a crazy shaggy crest, they clamber gracelessly around in the trees, often holding their wings out for balance. The chicks actually have claws on their wings, which they use to climb back up into the shrubs after dropping into the water to avoid predators. Their cow-like digestive system is unique among birds, and allows them to digest leaves via bacterial fermentation. As a result, they smell and probably taste like cow manure, which keeps them safe from local hunters, though many other big birds along the river have been hunted into scarcity.


The Peruvian Amazon is pretty deep in South America, so few of our neotropical migrant birds make it that far – most winter in Central America and the Caribbean. But a few ambitious migrants do make it to the Amazon, including shorebirds like Spotted and Solitary Sandpipers, Purple Martins, Chimney Swifts, and Barn Swallows, thousands of which were staging along the river last week ahead of their return trip north, perhaps even to the Cape. We also saw a few Ospreys that almost certainly came from the northern United States. Since many of our local nesting Osprey have been back for a couple of weeks now, these were most likely juveniles that won’t be returning north to breed this year. Kind of like recent British high school grads, young Ospreys do a “gap year” in South America before returning north to attempt breeding as two year olds.


While the Osprey’s arduous 3000 mile journey home from the Amazon powered only by their own wings may seem impressive, I would submit that it’s nothing compared with surviving the red-eye from Lima seated next to a couple with two overtired toddlers. Now that was arduous.