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Vida Libre: How a landfill is supporting Andean Condors in central Chile

 

February, 2024

Andean Condors scavenging at the landfill. All images courtesy of Eduardo Pavez.


 One day in 2005, Eduardo Pavez was contacted by KDM Company, a landfill management operation in Central Chile. At the time of this call, he was researching condors and working as a wildlife consultant for Bioamérica Consultores. He had also founded one of the first rehabilitation centers for raptors in South America, which currently operates under the auspices of the Unión de Ornitólogos de Chile. Since 1993, the center has admitted 148 Andean Condors (Vultur gryphus) from what Eduardo refers to as “vida libre,” meaning free life. Of those admitted, 90 have been released back to their free life. Chile is a small enough country that Eduardo’s work made him the condor guy. KDM called because seven condors had been poisoned at their site, and they knew Eduardo could help.   

 

Andean Condors are among the largest birds in the world. As obligate scavengers they rely on decaying animal matter, termed carrion, for sustenance. In central Chile, human livestock practices strongly influence the distribution of carrion available to Andean Condors. Landfills are predictable, and predictable food sources often alter the movement patterns of wildlife because understandably, most animals avoid working hard to find food if they don’t have to. Condors are no different.

 

On the day of that call, the seven poisoned condors were transported to the National Zoo’s veterinary clinic for care. Five of them died. The two that survived were transferred to Eduardo’s Raptor Rehabilitation Center where they recovered fully. Prior to release, one condor was fitted with a satellite transmitter. For three years Eduardo and his team were able to study that individual, and eventually they discovered the bird on a nest. A new vida libre.    


Adult female soaring in central Chile with broad wings, some of the largest of any bird. 

 

Although the presence of landfills can aid in condor survival by offering reliable food, they can also harm condors at the individual and population levels. Since the moment Eduardo was contacted by KDM, they have joined forces to study the relationship between condors and the landfill, in hopes of implementing measures to avoid negative impacts to the birds. One result of this collaboration has been a 17-year-long study of the site, during which Eduardo and his team have observed four poisoning events affecting 14 condors, 8 of which died as a result. Most of the afflicted were males, likely because adult males dominate over other condors at desirable food items. When those choice items are toxic, the males experience the worst of it. The poisonings were due to organophosphorus intoxication, which occurs when condors consume organophosphorus pesticides and suffer negative affects to the nervous system, and sometimes respiratory paralysis. The exact source of this poisoning was never revealed. 

 

Additional findings from the study show that condor numbers at the landfill are directly linked to the presence of available food in the surrounding landscape, namely the carcasses of cattle and rabbit. Condor numbers at the site fluctuate depending on the movements of grazing livestock across the region. Notably, condor numbers at the landfill decreased between 2013 and 2016, correlating with widespread cattle mortality due to drought, and rabbit mortality due to myxomatosis disease. And influx of carcasses available on the landscape drew condors away from the landfill. After 2019 both mortality events subsided, and condor numbers at the landfill increased. Eduardo says that this trend “shows how the presence of condors in landfills offers an indicator, a very sensitive barometer, of what is happening with the food supply on a broad geographic scale.” Andean Condors star as proxies for the environmental health of the places in which they reside, a trait that many scavengers exhibit, but few receive credit for.

 

Another interesting finding over the course of the study was that the age and sex ratios of condors at the landfill suggest those at the bottom of the social ladder (juveniles and females) visit the landfill more often than adult males. Successful scavenging is more difficult for young birds and subordinate individuals. Landfills offer easier pickings for those who might be bullied off of choice carcasses by adult males elsewhere. Condors, like many large raptors, undergo a lot of trial and error in their first years of life as they learn how to obtain food successfully. For condors specifically, social hierarchies at feeding sites require skillful interpersonal navigation, and young birds usually get the short end of the bone.  

 

A young male appears submissive in front of an old male. Condors are very hierarchical, with males dominating over females and the old over the young.

The results of this study were published in the December 2023 issue of the Journal of Raptor Research, in a paper titled “Landfill Use by Andean Condors in Central Chile.” The story has since been picked up by over eight news outlets around the world, including Spektrum, Science Magazine, LabManager, BNN, and Phys.Org. The popularity of this story speaks to the public’s interest in Andean Condors, as well as the uniqueness of this collaboration between a landfill management company and a passionate team of condor researchers. All too often we hear tales of companies abdicating responsibility for their role in affecting wildlife, but here, we see something different — shared intent to help these incredible birds stay healthy, to help them fulfill una vida libre.

 

Andean Condors, like all vultures, are important agents in the recycling of organic material across the landscape. They remove rotting flesh from the ground, for free, and they do it efficiently. Their continued existence in our skies is a worthwhile priority, not only in central Chile, but across the globe. After years of working with the condors, Eduardo speaks of them in poetic, strong terms — “When you contemplate the flight of the condor, it's easy to understand why it has been so relevant to Andean cultures since time immemorial. It is difficult to conceive a more beautiful, impressive, and harmonious spectacle. For many, he is the messenger, the one who carries men’s prayers to the top, where the Sun god lives. Working for the conservation of the condor is working for the conservation of an umbrella species, since under the shadow of its great wings inhabit many human and natural communities that need to be known and conserved.”

Adult male, probably of advanced age, due to the large size of the crest, dewlap, and folds on the head.



Meet Eduardo Pavez

Eduardo is general manager at Bioamérica Consultores and former president at the Unión de Ornitólogos de Chile. He is founder of the Rehabilitation Center for Birds of Prey of Chile and is the current director of the Andean Condor Conservation Project, or Manku Project, as it is known.

Andean Condor Art Gallery


Eduardo has generously offered to share here a collection of his scientific illustrations, done with rapidograph pens. Each drawing takes months of work. Among the intense daily activity, for Eduardo the hours of silence and thought, generally at night, is an activity that he considers therapeutic. Thank you Eduardo — for loving Andean Condors, and for depicting their beauty in memorable detail. These pieces speak for themselves. Welcome to the gallery.

Artist’s Statement

Eduardo, born and raised in Chile, has always been passionate about nature. In the early 80s, as a teenager, he self-taught himself to practice falconry with eagles and rehabilitate birds of prey. In addition to his work with captive raptors, Eduardo has dedicated much of his life to studying and observing them in nature. In addition to conducting research, he produces detailed illustrations of condors in a style reminiscent of the ancient naturalists whom he admires greatly. Eduardo has generously agreed to showcase some of his beautiful work here. In describing his hopes for this art, he says “sometimes a drawing, which is a representation of reality that passes through the filter of the artist’s consciousness, can transmit an even greater force than a photograph. Through my drawings I try to express what I feel and the strength that birds and condors transmit to me. I also intend to teach about their behavior, anatomy, or, in the case of condors, their physical characteristics associated with sex and age.” Eduardo also believes that portraying the condors in their natural habitat, and doing so in black and white, adds additional power to the impact of the illustration.



Juvenile female Andean condor less than one year old, recently hatched from the nest, faces the glaciers and cliffs of the Andes Mountain range of central Chile.

Adult female Andean condor, over eight years old, in the mountain range of central Chile.

Juvenile 3-year-old male Andean condor in the Cordillera del Paine, Chilean Patagonia.

Behind the clouds and the head of an adult male Andean condor hides the summit of Mount Aconcagua, the highest peak in the Americas with its almost 7,000 meters of altitude.

When I was 12 years old, I had to rest for several weeks due to an illness. To kill time, I made this drawing with a fountain pen, which turned out to be premonitory. At that moment, although I had been dreaming about birds for a long time, I did not imagine that in the future I would dedicate a large part of my life to condors.

Represents Patagonia during the Pleistocene. That was a time that I love, a time when animals populated the human spirit inspiring cave paintings, a time when the silhouettes of many species of giant vultures soared through the skies of the Americas.

I thank Zoey Greenberg and the prestigious Raptor Research Foundation for giving me the opportunity to disseminate part of our work and my modest naturalistic art.


Interview with a Raptor Researcher

At this year’s RRF conference in Albuquerque, Cheryl Dykstra received the Exceptional Service Award. This award recognizes RRF members who contribute outstanding work and service to the foundation. This year’s award goes to Cheryl for her notable work as Editor-in-chief of the Journal of Raptor Research (JRR), which just this year reached an all-time-high impact factor of 1.7. What follows is an interview with Cheryl on her career as a raptor researcher and editor.

Cheryl with a golden eagle, Aquila chrysaetos


Cheryl Dykstra, Editor-in-chief of the Journal of Raptor Research

 

Editor from: 2006 to current 

Years as an RRF Member: 28 years (1995 – current)

Favorite raptor: Red-shouldered hawk

Current position: Owner of a small research and consulting firm, Raptor Environmental, and Editor of JRR

Current research projects: Breeding ecology of urban red-shouldered hawks; survival and movements of juvenile American kestrels; survival and movements of Henslow’s sparrows

 

When and how did you first become interested in studying raptors?

I love working with all bird species. I learned how to do ecological field and lab research doing my master’s degree on house wrens at the Leopold Reserve while at the University of Wisconsin–Madison. I then had the opportunity to pursue a Ph.D. studying Great Lakes bald eagles. In addition to working with such an iconic species, I knew it had to be easier to take blood samples from an eagle than from a wren! My research showed that the depressed reproductive rate of Lake Superior eagles was likely not a result of the legacy contaminants DDE and PCBs (which were decreasing), but was due to the natural low productivity of the oligotrophic Lake Superior. Since then, I’ve never looked back – I’ve been fortunate enough to be able to work with raptors ever since. I’ve studied urban/suburban red-shouldered hawks in southern Ohio for the past 25 years, and have also had opportunities to research barred owls and kestrels in this region.

 

How did you become involved with editorial work?

I’ve always enjoyed scientific writing, and the satisfaction that comes with finishing a project by sharing the results in a publication. My father worked as an editor for most of his career, and my brother started a journal and served as its first editor, so who knows? maybe it’s in my genes too.

 

My work with JRR started when former JRR Editor Jim Bednarz asked me to serve as an Associate Editor and then a couple years later asked if I was interested in being Editor when he retired from the position. So Jim is entirely to blame!

 

Since 2006, I’ve been the Editor for 71 issues (8057 pages) of JRR, and I’ve also enjoyed working with Clint Boal to co-edit a book, Urban Raptors: Ecology and Conservation of Birds of Prey in Cities.

 

What is your favorite part of being an editor for JRR?

I love helping first-time authors, students, and international authors get their research published in JRR. Sometimes they have a lot of questions and sometimes their manuscripts take a bit more work, but it is gratifying to help shepherd their papers into print.

 

I also love working with the editorial team. JRR’s Associate Editors, editorial assistant, translators, publications committee, and the rest of the team are amazing! They are top-quality researchers volunteering their time to put together our journal, and we couldn’t continue to improve JRR without their dedication and expertise. On top of that, they are just excellent folks to know and work with.

 

Can you share a memorable moment in the field? Why was it worth remembering?

During my Ph.D research in northern Wisconsin, I had to climb a white pine to retrieve a weather station and data logger that we had placed 85 feet up in a super-canopy tree. When we arrived at the tree one day in late summer, we found that wasps had built a nest about 60 feet high and 10 feet from the trunk, and were circling busily around it. I had been taught to climb trees using only climbing spikes and my hands, with no lanyard around the trunk and with my rope trailing behind (in retrospect, perhaps not the safest technique!). Without pausing to think, I climbed to the first branch, about 50 feet off the ground, emptied a can of Raid spray toward the wasp nest, and then quickly rappelled down. Later that day, I returned wearing long sleeves, gloves, and a mosquito headnet (did I mention it was near 90 degrees that day?). I resolved to “sneak” past the wasps, so I climbed the tree again and got my face stung three times through the headnet in the process. But I kept going and did manage to safely retrieve our weather station and data. I think the reason it was memorable was the combination of stupidity with success.

 

What is something you wish more people knew about raptors?

Because I’ve worked with urban raptors on private lands for more than 25 years, I get to interact with many landowners and answer a lot of their questions. My top three most common answers are:

1)   No, my touching the nestlings will not cause the parents to abandon their nest.

2)   No, that raptor won’t kill your dog or cat.

3)   If raptors target your bird feeder, you’re still feeding birds, just different birds than you intended.

 

What has kept you invested in raptor work?

I think my answer will be the same as a lot of other folks in RRF. I’m passionate about raptors and want to contribute to their conservation, in whatever way I can. As we all know, raptor populations are vulnerable to anthropogenic threats and are likely to become more so in the face of increasing urbanization and climate change. Much of my research has focused on responses of red-shouldered hawks to urbanization, and I’ve been excited to see articles about their behavior, dispersal and survival, and reproduction published in JRR. And as a Christian, I also feel I can serve by doing my part to be a steward of the environment and the created avian biodiversity.

 

I’m also excited about talking to students about birds and conservation, helping them become engaged with the natural world. Raptors are fabulous “gateway” birds—few people can resist a raptor in the hand. Mentoring students and volunteer researchers in raptor and songbird research has been one of the highlights of my career.

 

And of course, working with raptors is just fun! I love being outside in wild areas, climbing to nests, and having an excuse to capture and study raptors. For my red-shouldered hawk research, I often get to travel to Hocking Hills in southeast Ohio, and I’ve enjoyed visiting raptor researchers studying Harris’ hawks in south Texas, peregrine falcons in Washington, and golden eagles in California. I also loved attending RRF conferences in places like Veracruz, Scotland, and South Africa.

 

What piece of advice would you offer to those early in their career of raptor research?

Keep at it—don’t be discouraged. Raptors (and other birds) need you more than ever. And don’t be afraid to contact us “senior” raptor professionals for help: advice, field opportunities, writing assistance, etc. We are a friendly lot (most of us!) and we sincerely want to help students advance their goals and careers. Volunteering with field research, at raptor rehab centers, or at your local museum or nature center is a great way to get started. Early in my career, I took classes at a field station, taught courses on ornithology, and volunteered with other graduate students to learn more about fieldwork. These are tough times for young wildlife ecologists, but all of us want you to succeed at bringing raptor conservation to the next generations.

 

You can view Cheryl and Clint’s book Urban Raptors: Ecology and Conservation of Birds of Prey in Cities here and explore the Journal of Raptor Research here.

 

Thank you Cheryl for all that you do!


It Began With a Vulture

Introducing your science writer and what it means

to be part of a raptor-loving community

Photo courtesy Mia McPherson

The Turkey Vulture was my spark raptor. In my early years as an intern-of-all-trades, I was at Penn State’s Shaver’s Creek Environmental Center training an adult male Turkey Vulture. He was, objectively speaking, a menace. He relished untying my shoelaces, tugging me off ladders, and dumping buckets of cleaning supplies when my back was turned. He pecked holes in my pants. Vomited on my shoes. But at the end of the day, he was the spunkiest bird in the place, and he learned fast. I grew increasingly fond of those hunched shoulders and featherless head, and endeavored to understand as much as I could about vultures in hopes of improving their reputation, at least locally. What a long road. Most visitors were so repulsed by him they fled the scene outright, seeking reprieve in the hawks next-door. Sometimes, people screamed. While this annoyed me, it also exposed me to a truism: everyone loved the other raptors. From the vulture enclosure, I had a secret mew-view of visitors as they strolled through the center, and their reactions were priceless — a child grabbing their parent’s hand to drag them in front of the Barred Owls, pointing and jumping, look how big their eyes are. A woman placing her hand on her chest, standing in front of the Golden Eagle speechless, her other hand on her partner’s arm. A teenager sitting on a rock, drawing the female Red-tailed Hawk, a perfect interpretation of predator unfolding on the page. Raptors evoke a slew of emotions that hook and reel people into new awareness. Seeing an owl up close can, it seems, facilitate a mental shift as significant as reconsidering the state of our planet and the way we treat the organisms we share it with. Visitors left the raptor center caring about the fate of those birds. Even when vultures were not included on their list of species to write home about, I was moved by the weight of the transformation. My interest in this human response, and my unsullied love for vultures, led me to a group of people who turned their own raptor response into a career — the Raptor Research Foundation (RRF).

 

I moved to Hawk Mountain Sanctuary to further my training in vulture conservation, and while there, became a member of RRF. In attending RRF’s annual conference I discovered a passionate, dedicated, and creative group of individuals who share a common goal of supporting healthy populations of raptors worldwide, vultures included. My first RRF conference was memorable — I strolled into a lobby and found folks with beers in hand, donning retro raptor t-shirts, and casually discussing Turkey Vulture genome sequences. Clearly, I’d found my crowd. I was at the conference to present a middle school curriculum I’d built on Black Vulture movement ecology, and as an educator, I was an outlier in a sea of numerically inclined researchers. They welcomed me nonetheless. I’ve attended the conference nearly every year since, and shared many more beers with researchers who are wing-deep in the complexities of raptor biology, and who recognize the value of education and art in furthering the holistic mission of raptor conservation. The challenge of supporting raptor populations is, of course, global in scope and therefore necessitates collaboration. RRF provides the community support, logistical framework, and intentional atmosphere for this collaboration.

 

Six years and a master’s degree later, I now have retro raptor shirts of my own, and I’ve joined the RRF team. I am your science writer. In this role, I will support the Foundation’s mission by disseminating information about raptors from the Journal of Raptor Research and other outlets within the society. It’s no secret that bridging the gap between academic research and the collective consciousness of the public is a big feat. We know that (most) raptors lend themselves to storytelling through their objective beauty, predatory prowess, and compelling life histories. They turn heads. Most fourth graders can list off several raptor facts, such as the speed of a Peregrine Falcon in a stoop, or the rotational capacity of an owl’s head. But the journey of how those facts reach their packaged and recitable form is often cloaked from the public eye. My job is to pull back that cloak — to craft writing that presents the academic accomplishments of the raptor research community to a broader audience, without compromising accuracy.

 

This post initiates a new RRF Blog which will serve as a platform for accomplishing these goals. On the blog you will find posts highlighting articles published quarterly in the Journal of Raptor Research, interviews with raptor researchers, guest blogs by members of the RRF community, notable member achievements, and more. At its core, this will be a hub for raptor research stories from multiple angles. For now, new posts will be announced on RRF’s Facebook and the announcement section of the RRF website. If you would like to post a guest blog on your focal species, the story of your project, or wish to nominate an interviewee for a raptor researcher highlight, please contact me at science.writer@raptorresearchfoundation.org. I can’t wait to hear from you.


Zoey is the science writer for the Raptor Research Foundation and the associated Journal of Raptor Research. She has spent over a decade writing and teaching about raptors. She is particularly interested in the lives of vultures and is a North American co-compiler for the IUCN’s biannual update on vulture research. She facilitates outdoor writing workshops for Freeflow Institute and works as a naturalist for Lindblad Expeditions. Zoey has a B.A in human ecology from College of the Atlantic and an M.S. in environmental studies from the University of Montana, where she wrote a thesis of prose poems critiquing conservation ethics. Zoey grew up in Bellingham, Washington, where the Salish Sea and temperate rainforest was a catalyst in sparking her love of the pacific northwest coast. When she’s not on ships or writing about raptors, she enjoys volleyball, ultimate frisbee, bellydance, and the color turquoise.