Isidor's Eagles: Owners of the Cloud Forest
Ursula Valdez— 17 July 2000 — in Neotropical Environmental Education Program    ShareIt was about 11 years ago when I saw an Isidor's Eagle (Oroaetus isidori), also called Black-and-Chestnut Eagle, for the first time. I was crossing the cloud forest on my way to Amazonian lowlands in Peru. From a comfortable tourist truck that was giving me a ride, I could see a fantastic scene. A few meters from the road there was a mossy tree emerging from the steep slope and on the top of it there was a nest with an Isidor's Eagle and a nestling. I remember jumping from the truck and staying while the tourists were heading to a lodge not far down the road. I stayed there for three hours just watching the eagles, and I was fascinated with the experience. By that time I was a newly graduated biologist looking for a direction for my career and my interest in birds, and especially raptors, was starting to grow. Sadly, years later I found out that the eagles were not nesting there anymore, a man had cut down the tree and since then there was not evidence of a nesting activity around. During the next years, however, I had the chance to pass by that road several times and some of those I still was lucky to see an Isidor's Eagle flying along or across the valley.

By July of 2000, I was hired by The Peregrine Fund as a research biologist and I was assigned to find breeding pairs of Isidor's Eagles in South America. After a talk with Rick Watson where I told him about my sightings in Peru, we decided to search for the eagles on the cloud forest of the Cosnipata Valley. As a Peruvian biologist I considered this a great opportunity to conduct research in my own country and with raptors that have became my passion. But I was also excited about going in search of those enigmatic eagles that years ago fascinated me and that inhabit the pristine cloud forest of the southeastern Andean slopes of Peru.

After some paperwork and lots of bureaucracy in Lima (capital of Peru), I departed to Cuzco, a small city high in the Andes, which became our contact with civilization and source of supplies. In mid-July, after getting food supplies and all we may need for the following weeks, my assistant, Cynthia King, and I left Cuzco towards our field site. A dirt road that joins Cuzco and the Pilcopata Valley took us to the cloud forest inside of Manu Biosphere Reserve, the largest and most famous protected area in Peru.

Since the very first field trip, each journey has been an adventure—breakdowns, flat tires, landslides and waiting, sometimes days, for huge earthmovers to clear them, a truck jammed against a cliff after a misjudged corner, gruesome accidents at the bottom of the precipice, and more. The mountain road itself shows one of the most peculiar (and scary) transit systems. The road is so narrow and with deep precipices that traffic going down to the lowlands is allowed only three days a week (Mondays, Wednesdays, and Fridays), while traffic going up goes on the rest of the days. On Sundays when there is not much traffic, vehicles are allowed to go in both directions—at one's own risk. Of course, more than once we found a truck coming in our opposite direction. I swear, every time we had checked carefully which day to depart.

In many places along the road we saw crosses with flowers and some inscriptions marking the location of accidents and deaths, as a reminder of how careful you need to be when driving this road. However, every trip was a fantastic journey going across the high Andes; contemplating the high and vast mountains, and going through passes to the eastern slopes that go down to the Amazonian rainforest. On the highest location of the road we stopped the vehicle to look at the fantastic scenery: a green carpet-like vegetation covered the slopes below and then far in the horizon we could see the Amazonian plain.

When we arrived in our study area, Cynthia and I explored for several days, walking up and down many hours along the road. We camped in wet forests where mornings and nights were in fact wet and cold. Then we went through a mysterious and magic cloud forest, in which we walked under the rain or through dense fog. But we did not complain. We also had magnificent sunny and blue-sky days. During the walks, I stopped every bird-watcher we found along the road (not many) and asked if they had seen the eagle. Several times I just had a sympathetic smile for an answer as most of them consider the Isidor's Eagle one of the hardest species to see. But finally, by mid-August our efforts were rewarded with the sighting of our first Isidor`s Eagle high in the sky. Despite our exhaustion we jumped and celebrated with hugs and dances. For a couple of days we were able to see the eagle around the same area. On the same field trip, we found another Isidor's Eagle flying in a higher elevation locality. We were so excited. Our first goal was achieved: we confirmed that Isidor's Eagles were living in our study area. The next step was to find more individuals and nesting sites.

For the next three months my colleague, Sophie Osborn, gathered information on more individuals of Isidor's Eagle and their behavior, and the areas they frequently areas. In January 2001, during the visit of Rick Watson to our study area, we decided to put all of our efforts into finding a nest of Isidor's Eagles and in trapping an individual so we could radio track it. More challenges, but we took them again with my new and determined crew (Bryan Evans, Jose Campoy, and Daniel Huáman as my field assistants).

During the next five months we had one of the most fascinating experiences watching these eagles and observing their behavior. We will hardly forget the day we witnessed, not far from us, a young individual flying with its parents. Or when we saw the adult pair displaying to each other, grappling talons in mid-air and cartwheeling from the sky toward the forest canopy, and minutes later, mating. I observed in awe as an adult Isidor's Eagle captured a woolly monkey. Unfortunately, we haven't found a nest yet, but we found certain evidences of nesting activity. Our trapping attempts were unsuccessful as well. However, so far we have gathered information on the behavior and important aspects of the biology of the Isidor's Eagle.

No matter how much longer we need to keep searching for eagles’ nests or how many more long days we need to walk, we need to know more about Isidor's Eagles. We know, though, that Isidor's Eagles are the lords in the cloud forest and we hope they remain like that for a long time.

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