There is one condor I’ve gotten to know well over my time as a collaborator with the recovery program. The story of his life encapsulates the hopeful advances and the difficult challenges the species has experienced as a whole. California condor 401 hatched on April 13th 2006 at the Peregrine Fund’s World Center for Birds of Prey in Boise Idaho. As opposed to being raised by zoo keepers wearing condor puppets (i.e., “puppet-reared”), 401 was reared by his mother, condor 56 “Kareya” and father, condor 71 “Tapu” and released to the wild when he was about a year old to fly over the hills of central California and help his species recover from near extinction. I first encountered 401 by way of his blood sample that was collected during routine health monitoring in the spring of 2009 and sent to my lab to be archived for future analysis of lead. Lead poisoning is the number one threat preventing California condor recovery in the wild and my research includes measuring lead isotopes in condor blood samples to identify sources and effects of lead exposure.
Condor 401’s blood sample came to my special attention ~ six months later because a radiograph taken of him when he was admitted to the Los Angeles Zoo for treatment of lead poisoning showed he had been shot.
His wounds had healed but he had four birdshot pellets embedded in his soft tissue and curiously, he was the third condor that had been found to have been shot within six months (to read about this case see http://www.fws.gov/cno/es/calcondor/PDF_files/2014-9-Finkelstein-Enviromental-Research.pdf). Condor 401 survived his lead poisoning treatment and was released back to the central California countryside.
Less than a year later, in June 2010, condor 401 was back at the Los Angeles Zoo being treated for one of the highest blood leads we had seen up to that point – ~560 µg/dL! (Unfortunately in the past few years we have seen several other condors with equivalently high and lethal blood lead levels). Another radiograph showed that condor 401 had eaten a lead buckshot. 401 was fed rabbit fur to get him to expel the lead item without surgery. Luckily the rabbit fur worked and 401 regurgitated the buckshot! After a few months of intensive treatment by his amazing and talented medical staff, condor 401 recovered and was released again to fly free above the hills of central California.
But 401 was not going to be free for long – over the course of his short life in the wild he was treated for lead poisoning at least five times with the last and fatal poisoning event ending his life on June 15th 2014. Condor 401 was only eight years old when he died – just a teenager and well below his ‘normal’ lifespan of ~ about 50 years of age. Importantly, in terms of his species’ future survival, he would also never have the chance to reproduce.
I wish I could say that 401’s case was unique, but sadly it is not. Approximately half the condors free-flying in California have been treated for lead poisoning at least once, with many birds being treated more than once. Lead poisoning is the number one cause of mortality for free-flying juvenile and adult condors and our research has shown that condors are primarily lead poisoned by eating animals that have been shot with lead-based ammunition. With so many alternatives to lead ammunition available we are hopeful that one day a condor (or any scavenger) can eat their dinner without risk of being poisoned by lead. May 401’s suffering and death be a reminder to us all about the health risks from lead ammunition (for more information see https://escholarship.org/uc/item/6dq3h64x).
For more information on hunting with non-lead ammunition please see http://huntingwithnonlead.org/.
California condor juveniles have darkish grey heads and necks and then around four years of age start to become more and more pinkish/orange/red (see the field guide for more information and photos of examples here and at the bottom of the wreness’s slidshow here) until they are about six years old when they obtain the full coloring of a mature adult. However, like everything, a condor’s color is not so simple. We have some special thoughts and tips about a condor’s ability to change their coloring from Mike Clark (aka the Condor Whisperer) who works at the Los Angeles Zoo and is truly one of the heroes of the condor recovery movement.
Here are Mike’s thoughts/observations:
In my opinion females have a yellower coloration from the malar stripe forward than males. Of course it varies from bird to bird. but if you put them side by side I find the females have a yellower face generally from the malar stripe forward. Males can have the same yellow in this place but it is usually shaded with a little more flushed coloration mixed in . This is not a hard and fast rule obviously.
Here are some examples of the male/female difference:
Intensity of color varies widely. When birds are upset or angry around the nest or young the colors intensify. They also go starkly pale when in fear or being pursued (like by someone with a net when being trapped for health check-ups). [We don’t know what happened before this photo was taken, but Condor Watchers observed a remarkably pale female 190, aka Red 90, here]
Another observation is that the mature adults tend to have a bluish neck. [Again, CondorWatchers recently noted a particularly blue neck here] When they get a hold of food and start to dig in on the food the neck flushes (if its exposed and the ruff isn’t up) and the neck turns more purple than blue.
I think the bird’s diet, and beta carotene in particular, has very drastic effect on coloration of the birds’ faces. [Although we think of orange vegetables as sources of beta carotene, it is also found in meat and especially liver]
Can you guess from the descriptions above who here is the male and female of a current breeding pair at the Los Angeles Zoo?
Let us know if you see any extreme examples of these color variations by tagging the photos – especially if you see a condor with a bluish/purplish color when feeding! Who knows, maybe we will learn something new about condors and colors!
International Vulture Awareness Day is today! All across the globe, zoos and conservation organizations are holding special activities to honor these charismatic and often threatened scavengers. For more information: http://www.vultureday.org/2014/index.php
Slide shows. Our amazing moderator wreness has put together slide shows of condors and other species from various angles and in different lighting to aid with identification. She even highlighted body parts — condor feet anyone? http://goo.gl/Jtg3GV.
Her nice contribution was showcased by the DailyZoo here: http://daily.zooniverse.org/2014/08/26/condor-images-slide-show/
New study. Led by 2 scientists on the Condor Watch science team, a new study investigates and links the illegal shootings of 3 condors: 286 (Black86-2dots), 375 (Black75-3dots and Blue75), 401 (Black01underline and White1). Read it here: http://goo.gl/kZ24dE
Female 444. We were all rooting for 444, a female condor nicknamed “Ventana”. The oldest wild-reared condor in the central California flock, Ventana was badly lead poisoned last month. LA Zookeeper Mike Clark posted this report on his team’s efforts to save her life:
“Latest case of lead poisoning female condor 444. A wild fledged bird from Big Sur clinging to life currently. Just finished her second blood transfusion. At an impossible weight of 10.3 pounds she is a fighter. Unfortunately she has lost most of her appetite and has to have a small amount of food placed in her mouth bit by bit. All hands are on deck for this girl and we won’t give up until she does. Wish us luck.”
Despite their hard work on her behalf, she died on August 26th. At her passing, Ventana Wildlife Society noted “Ventana…was invaluable to the condor recovery effort in that she did not grow up in captivity and was raised in the wild by condor foster parents with minimal human intervention. RIP Ventana.”
Male 125. Earlier in the summer, on July 18, 2014, the southern California flock lost male 125, who died of suspected bobcat predation. At 19 years old, he was a seasoned and successful breeder with a chick in the nest, making his loss particularly difficult. Fortunately, his partner, female 111 has been able to continue to rear their 2014 chick.
Here is a nice writeup on his contributions to condor recovery: http://goo.gl/FT0Wfo.
The US Fish and Wildlife Service has a webcam trained on his nest and has posted numerous videos of his charming chick, prompting one condor biologist to assert #condorsarecuterthankittens. See whether you agree here: http://goo.gl/II86MJ, http://goo.gl/o3nvds, http://goo.gl/VMJ3UC, http://goo.gl/cKPyid.
Lead testing. US Fish and Wildlife Service distributed this excellent short video that describes blood lead testing, lead poisoning, and chelation treatment of wild California condors. Look for Condor Watch feeding site photos at 1:51! http://goo.gl/0jClU4
Summer travels. The US Fish and Wildlife Service shared the GPS tracks of condor 567 over a 3-week period. Although this degree of wanderlust is somewhat unusual, the condor’s huge wingspan is custom-made to enable them to range widely in search of food. USFWS notes:
“Check this out! Condor #567, a 4-year old wild-fledged male condor, took a trip on the wild side over a three week period in July – from just north of Los Angeles early in the month to 12 miles south of Livermore in northern California later in the month — sightseeing the Coast range soaring…..“
It is the job of California condor release site managers to monitor the condor flock. What this means is that they must attempt to locate every condor in their region on a daily basis. This kind of monitoring is above and beyond what is done for other species. Can you imagine trying to locate every single bluebird or coyote on earth, every day of the year? Such a feat is made possible only by the year-round work of biologists and volunteers, technologies such as radio and satellite telemetry (a.k.a. GPS), the regular capture of individuals for wing-tagging and blood lead tests, and the restricted condor population and range. Even with these advantages, it is a rare day that every individual bird is contacted. Once a condor has been off the radar for more than three days, targeted attempts are made to get a “visual” (visual observation) or a “signal” (radio-transmitter signal). After 5-7 days flights are chartered to search the remote parts of the condor range for the missing bird. Finding missing condors is important whether they are living or dead. If a condor is sick or injured, then they can be captured and treated. If they have been killed, determining the causes of death is also vital to the success of the program.
As an intern for Ventana Wildlife Society and Pinnacles National Park, I got the opportunity to track these amazing birds in the wild. Here’s an abridged description of a tracking day, one of the essential management responsibilities of California condor recovery partners:
A day of tracking usually starts at 9 a.m. or later, when condors are up and moving. Thermal updrafts, which occur when the ground is warmed by the sun and the surrounding air rises, are a boon to a foraging condor. So condor watching doesn’t require the pre-dawn motivation that other bird watchers must muster. Once at the office, we look at our records for the previous day’s condor activity and set our game plan for the day based on specific individuals we are looking for, or where a wild carcass may have been spotted.
As we drive or hike through condor territory we stop often to “take signals.” We receive the signals emitted by radio-transmitters on the birds wings or tail feathers, using a directional antenna and handheld receiver (as pictured). Since each condor has its own unique frequencies, we can tell who we’re hearing, and in what direction they are from our location. Additionally, by listening closely to the intensity of the signal we can make some assumptions about distance from the observer, and whether the bird is perched or flying. Over the course of the day we may get multiple signals from the same bird that may indicate longer range movements within their range (between canyons or even between release sites). Over the course of a tracking day we will also make visual observations of the condors we come across. These observations may just be a flyby, but when we’re lucky we might get to see the birds feed, or display mating behavior. All of this information is recorded in order to document the relative health of the bird (e.g. no symptoms of lead poisoning), monitor breeding efforts, and provide insight into location of the bird if they do go missing.
A tracking day usually ends at about 4 when condors are starting to seek out their roost for the night. When we make it back to the office we input this data and eventually incorporate it with GPS data downloaded from satellites. Hopefully, we contacted all the birds we were looking for! If not, we will increase our efforts to contact missing birds the following day.
I was brought onto the condor project by my collaborator and friend Dr. Myra Finkelstein to help decipher potential variations in California condor diets among the flocks in central and southern California. Up until then, I had only seen live California condors at the Santa Barbara Zoo and stuffed condors in a diorama at the Santa Barbara Natural History Museum. When the opportunity arose for me to join the US Fish and Wildlife Service for their summer condor round up and bird examination in summer 2011, I jumped at the chance.
My son Jeremiah was four years old at the time and he and my husband Christian had already accompanied me on several field excursions related to my other projects, so I invited them along for three days at the Bitter Creek National Wildlife Refuge. We drove to their field site and met with the scientists who would be rounding up the birds for health monitoring, testing for lead poisoning, and blood sampling and drove to the condor pen. It was over 100 degrees, so very hot and somewhat desolate, but beautiful.
My job was minimal – watch the USFWS personnel catch the condors from the capture pen, label the blood collection vials and hand them to the scientists drawing blood, and keep my blood samples cold in a small cooler I had brought along for sample transport. I would spin the blood in a centrifuge later, back at our hotel, to separate the red blood cells from the plasma portion of the blood. I would later prepare these samples for stable carbon and nitrogen isotope analysis in my lab at the University of California San Diego. I then combined these data with isotope data from blood samples previously collected from these southern California condors and from birds in the central California flock to better understand potential dietary differences between the flocks and how these diet differences affect the health and well-being of the condors.
The most amazing things about being up close to California condors were their incredible size and their overwhelmingly ugly-but-beautiful faces. It’s one thing to know that condors are the largest terrestrial bird in North America, with wingspans that range to three meters, but it’s another thing to actually see these birds up close and truly understand what such a large size really means. And, up close, their faces are so incredibly fierce and intimidating, that one can clearly see they share a common ancestor with dinosaurs. These birds look dangerous, but they were very mellow to handle and the USFWS personnel did an excellent job processing each bird. I have worked with many animals species in my work as a food web ecologist, but the condors are definitely one of my favorites. Especially because I got to share the experience with my young son.
Dr. Carolyn Kurle and her then 4 year old son Jeremiah getting their first glimpse of free-flying California condors at the USFWS capturing pen in summer 2011 at the Bitter Creek National Wildlife Refuge in Southern California.
The incredibly large wingspan of a California condor.
Dr. Kurle and her son organizing blood samples and preparing tubes for blood collection.
The beautifully “ugly” face of the California condor.
Condor Watch photo highlights
When you look through Talk at all the beautiful, interesting, funny, and unusual photos, and the astute and humorous comments of our Condor Watchers, it’s almost impossible to select just a few highlights. We could have picked 100. In the interest of not overwhelming you all, here are just a few.
- Here’s an image tagged by wreness capturing the impressive wingspan of 332. http://talk.condorwatch.org/#/subjects/ACW00042x1
- oldhitchhiker2 gave these birds kudos for their cheerleader formation. Great diversity of tag patterns too! http://talk.condorwatch.org/#/subjects/ACW0003zeb
- Canmore1919 spotted a condor conga line starting up. http://talk.condorwatch.org/#/subjects/ACW00015zg
- It’s the Luis Suarez of the condor world, caught in the act of chomping on a conspecific. Red card! Photo was tagged by wreness. http://talk.condorwatch.org/#/subjects/ACW0004ok0
- And here’s an excellent view of unusual tag A4, which looks confoundingly like 44, reported by miltonbosch. As wreness would say, Bravo, you win a fish!
It’s always fun to see some of the other charismatic fauna that frequent the feeding stations.
- Here’s a gorgeous golden eagle shot spotted by colin_2. http://talk.condorwatch.org/#/subjects/ACW0003n3g
- And this big-pawed black bear tagged by bliedtke and others. http://talk.condorwatch.org/#/subjects/ACW0002313
- And this simply awesome big cat tagged by mendocinosunrise. http://talk.condorwatch.org/#/subjects/ACW0002z23
- And finally, we know there’s still a lot of raven animosity out there, but wreness tagged this winsome “raven with tutu” photo, which makes us smile. http://talk.condorwatch.org/#/subjects/ACW000143j
Condor news and views from around the web:
- Mike Clark, LA Zoo’s condor keeper, shared this delightful video of a condor pool party. Unfortunately, the of the main reasons wild condors end up in the zoo is treatment for lead poisoning: http://goo.gl/xfyPEv
- This radio piece features an interview with the Yurok tribe about the proposal to release condors on the North Coast in California. “They haven’t really been seen in this area for 100 years,”says Tiana Williams, a biologist and Yurok tribal member, “but they figure heavily in our stories and feature heavily in our world renewal ceremonies.” http://radio.krcb.org/post/groups-seek-return-condors-north-coast
- And all on their own, California condors are slowly expanding their range. A three-year-old female condor, 597 (Black 97), caused a stir recently when she was caught on a private land owner’s wildlife camera in San Mateo county. This was the first condor sighting this far north since 1904. http://www.mercurynews.com/science/ci_25959192/first-california-condor-spotted-san-mateo-county-since. And in early June, came the arrival of the first condor to hatch in the wild in Utah since condors were reintroduced in 1996. We have not heard an update on the status of this chick since then. http://kutv.com/news/top-stories/stories/rare-california-condor-chick-hatches-utah-11747.shtml
- Several different video clips have been posted recently of action at feeding stations and elsewhere that we miss in our photo stills. Not for the squeamish, here a condor eats a very gloopy calf lung, courtesy of Hunting with Non-lead Bullets: http://goo.gl/UHpdvj And while it doesn’t always work out this way, here’s a clip of a condor chasing an eagle from a carcass, also from Hunting with Non-lead Bullets: http://goo.gl/32iquH
- Condors sometimes are lured into dangerous situations by road kill. Here a tourist filmed a condor causing a traffic jam on the highway in the Big Sur area. It’s Yellow8, aka 208, a female hatched in 1999: http://goo.gl/1RqZeR
- US Fish and Wildlife Service posted a clip of a 60-day old chick dancing the hokey pokey in its nest cave: http://goo.gl/j8BtcE
- Finally, we’ll leave off on some sad notes, the ones that for now always play in the background as we work for the future of condors. First, here’s a heart-breaking video of condor 401, in the final throes of lead poisoning. This guy hatched in 2006 and had been treated at least 5 times for lead poisoning. RIP 401 — you shouldn’t have had to endure this. http://goo.gl/fbVXm6
- And a photo of what the sand looks like after being traversed by a lead poisoned condor. The Peregrine Fund offers this description: When a California Condor suffers from severe lead-poisoning, the digestive system paralyzes, unable to pass food or water through the system. The bird is hungry, losing weight, dehydrated, and continues to forage and feed, despite the distended crop full of rotting meat. It will continue to pack food in, because despite the greater than 3lbs of food it possesses in the crop, it feels starved and becomes anemic. This condition, we call crop-stasis, is usually the last telling sign that the bird is withering away, and it will not be long before it dies. When a 13-yr-old male condor spends days on a beach next to the river, withering away, unable to fly, and barely able to walk, dragging his wings in the sand cause his strength can no longer hold them up, but he continues to saunter the 20ft to the river to drink water, it looks like this… http://goo.gl/MrJJQJ
Anyone living near southern California can attend a free screening of A Condor’s Shadow and meet Dolly, a 3-year old condor at An Evening With Condors and Friends – July 18th 7-9:30PM @Ojai, CA Libbey Bowl
The Wiyot Tribe of Humboldt Bay describes the origins of mankind through a tale of survival and rebirth. The creator of all things, Gouriqhdat Gaqilh, had become weary of the wicked ways of man and summoned a deluge to drown the Earth and destroy all living things. The sole survivor was the great Wiyot hero Shadash, or Condor, who started a new civilization cleansed of evil.
In 1860, about 100 Wiyot people were massacred while celebrating a ceremony honoring that tale of rebirth and survival. Like Condor, the tribe’s survivors endured. Today, the Wiyot still see condors—and condor feathers—as symbols of renewal. Recently, they performed their first World Renewal Ceremony in more than 150 years, with a gift of 48 condor feathers from the Sía Essential Species Repository. However, the jet-black plumage provides a glimpse into another story of survival—this time for the birds themselves.
These condor feathers reveal the chemical traces of lead poisoning, a serious continuing threat to the population in California. Despite decades of progress, scientists still intensively manage the birds in the wild and continue to treat the ones exposed to lead. A new state law offers hope that the birds may endure for centuries, but lead poisoning—once unseen and unappreciated—continues to play a part in their private lives today.
UC Santa Cruz toxicologist Myra Finkelstein is one of the researchers using feathers to tell this story. “Analyzing their feathers has really become a powerful way to understand what’s going on with these birds when they’re out there in the wild,” Finkelstein says.
The California condor is one of North America’s most impressive and rare birds. It is the largest land bird on the continent, with a wingspan stretching nearly 10 feet. Wild condors can soar as high as 15,000 feet, and they fly up to 120 miles per day. With their large, cherry-colored eyes, the bald-headed birds scrupulously survey the terrain looking for carcasses of deer, cattle, and other animals. They devour carcasses, or carrion, with razor-sharp beaks, and they can store up to three pounds of meat in a part of their esophagus called a crop. Although these scavengers can survive two weeks without a scrap, they rarely have to because they have complementary admission to an all-you-can-eat buffet at feeding spots high in the back country, courtesy of researchers.
In 1987, the International Union for Conservation of Nature designated the birds “extinct in the wild.” Conservationists placed all 22 known California condors into captive breeding programs at the Los Angeles Zoo and San Diego Zoo. In 1992, researchers reintroduced the condors to the wild and nurtured the population back to more than 400 birds. Today, more than half of these condors are free-flying in California and nearby states, but they are still “critically endangered”—largely due to lead poisoning.
Survival has not been easy. Wild condors produce only one egg per clutch, and it takes them about six years to reach sexual maturity. This makes their population especially vulnerable to environmental hazards, such carrion contaminated by DDT, power lines, wind turbines, and microtrash: bottle caps, wires, and bullet casings. However, lead poisoning poses the greatest threat.
In one study, scientists at the Minnesota Department of Natural Resources showed that lead bullets can fracture into tiny fragments, wildly scattering throughout an animal’s tissue like toxic hail. Only a few fragments are enough to poison a condor—equivalent to a few grains of sand. Condors unwittingly swallow these pieces after dining on unretrieved carrion killed by hunters.
Once this lead enters the bloodstream, it migrates into the birds’ tissue, bones, and feathers. Lead exposure irreversibly destroys the myelin sheath that protects sensitive nerves, setting off tremors and impairing coordination. Severe poisoning can shut down the digestive system. The only way to remove the lead is by flushing it out of their blood with chelation therapy, which binds the contaminant with a drug. But often, the damage is already too great.
Evidence that lead ammunition was harming condors first came from a UC Santa Cruz study in 2006. Environmental toxicologist Donald Smith and former graduate student Molly Church found that the blood-lead concentration of condors released in the wild had increased tenfold since they were in captivity. They determined that such severe lead poisoning could only arise if a bird had eaten lead and that the lead came from locally purchased bullets. In 2008, lead ammunition was banned in all condor ranges within California.
Even with the ban, things haven’t improved. “At least half of them have been lead poisoned and have had to be treated at the L.A. Zoo,” Finkelstein says. Today, paired with blood-lead analysis, tracing lead exposure through feathers has become a powerful research tool. Each condor is tested for lead at least twice a year—more frequently if the bird recently suffered from lead poisoning. But blood tests can only show the bird’s current lead poisoning. A single fully grown feather can reveal the bird’s lead exposure from the previous four months.
Testing the feathers require some high-tech tools. Researchers digest small pieces of a feather with acid, then pump it into an inductively coupled plasma mass spectrometer. This instrument uses a high-energy beam of electrons to ionize the feather solution with temperatures comparable to the surface of the sun. Now ionized, the feather atoms get sorted within a magnetic field, according to their mass and charge. A detector zeroes in on each sample, quantifying the feather’s lead.
Like human hair, feathers contain mostly carbon, nitrogen, oxygen and hydrogen—the essential building blocks of life. But when a condor has eaten lead, large amounts of the heavy metal show up in its feathers. This painstaking approach allows Finkelstein to measure the degree of poisoning during the months before the blood tests.
“We’re realizing that the blood monitoring isn’t even catching the tip of the iceberg for the degree of lead exposure,” Finkelstein says. “Even though the blood monitoring shows the lead exposure is of epidemic proportions and that they’re chronically poisoned, the feathers show that it’s way worse.” She found that one-fifth of free-flying condors have near-lethal or lethal blood-lead levels. And according to her population model, condors will only successfully recover when lead is completely removed from the equation. “The number of birds born just doesn’t make up for the number of birds that die. That’s what needs to change,” Finkelstein says.
She and a collaborator are now improving the model to predict how lead poisoning impacts condor breeding and how hazards such as microtrash affect the birds as a group—as well as other animals. “Condors might serve as a canary in the coal mine for other species that we aren’t actively tracking on a daily basis, but who are also foraging on animals shot with lead,” Finkelstein says.
The birds have a generously funded and well-staffed support system, which many other species don’t have. Scientists track condors using radio and GPS transponders. Indeed, the program’s researchers are daring adventurers, flying near treacherous ranges, and rappelling into unexplored ravines to find injured, poisoned, and deceased condors. The team performs full necropsies on each dead condor they recover to determine its cause of death.
“We know that other species are dying from lead poisoning, but we can make the link even stronger with the condors,” Finkelstein notes. “The amount of hands-on knowledge we’ve gained from them is phenomenal.”
California condors also have new allies who don’t need to leave home to find adventure: citizen scientists. Using the online Condor Watch program, condor fans can explore more than 170,000 photos taken at feeding stations. This helps researchers keep track of the birds and their wildlife neighbors, such as mountain lions, bears, and feral pigs. With each click, users can discover tidbits about each tagged condor. For instance, condor #32—the son of #42 and #39—was hatched in 2004 at the L.A. Zoo and is “still kickin’.” Aspiring condor aficionados can aid scientists and learn about their new feathered friends at the same time.
The scientific studies and public support are making a difference. In late 2013, California Gov. Jerry Brown signed AB 711 after reviewing expert testimonies and the results of Finkelstein’s research. The bill will ban all lead ammunition in California by 2019, marking a transition into a safer era for condors and other scavengers.
At least that is Finkelstein’s hope. She believes that the new law, alternative hunting ammunition, and increased public outreach through programs like Condor Watch will help the California condor population grow, stabilize, and thrive. But the threat of extinction is still very real. Californian zoos and organizations continue to treat lead-poisoned condors with chelation therapy. Despite the odds, the California condor may survive its own near extinction, much like its heroic namesake and the Wiyot people that revere them both.
Alex Tamura, an undergraduate majoring in astrophysics at UC Santa Cruz, wrote this story in spring 2014 for SCIC 160: Introduction to Science Writing.
Here at Condor Watch, we are using the data we glean from the feeding stations to ask many different questions that will help us better understand the ecology of California Condors. One of the major goals of Condor Watch is to understand how individual condors feed together. Using the identities of tagged individuals in photos, we can begin to construct the social network of California Condors. When you hear “social network”, you probably think of Facebook, Twitter, etc. And in effect, we are trying to building the “Facebook of Condors”. That is, we’d like to know which condors are “friends” that feed together, and potentially lead each other to feeding sites.
By combining information about individual histories of lead poisoning and the social network across time, we hope to understand how social relationships might affect the spread of lead poisoning through the population. We hope that this type of analysis will reveal important pieces of the puzzle for mitigating the effects of lead poisoning in this highly endangered species.
How things spread through social networks
The study of social networks originated at the intersection of sociology and mathematics, but it has increasingly become an important tool for ecologists as well. These studies have shown us how “social contagion” can facilitate the spread of all kinds of things–behaviors, ideas, germs, etc. Thus, understanding the structures of the social networks in which we live can help us who smokes or gains weight, or how we think and feel (see this TED Talk by Nicholas Christakis for a summary).
What do we know about social networks in animals? There has been an explosion of recent research investigating this question, and the results have been fascinating. For example, studies of animal social networks have shown that unique foraging strategies spread through social networks in monkeys, birds, as well as whales. Social networks are also important to the spread of diseases that are threatening animal populations around the world. For example, network structure can help explain how facial tumor disease spreads in Tasmanian Devils.
How to build the social network of California Condors
So, how can we apply these ideas about social networks to understand the dynamics of lead poisoning in California Condors? THIS IS WHERE WE NEED YOUR HELP! With your efforts in identifying individual birds in our photographs, we can start to piece together the social network of condors. Here is a little example of how this works:
Let’s say you saw these 5 photos…
From these photos, we can start to build a social network. It might look something like this:
Here, each circle, or “node” represents an individual condor, and the lines connecting them represent their propensity to feed together. Thus, individuals 3 and 12 are connected by a thick line because they always feed together (whenever 3 is seen, 12 is also there). We can already start to see some features of this hypothetical social network. For example:
- There are two clusters of individuals that often feed with each other (3, 6, and 12 vs. 31 and 5).
- Individual 14 feeds sometimes with both clusters–she is a “connector” of social clusters.
And these two patterns can have implications for the spread of lead poisoning if these social relationships turn out to be important. Say #31 and #5 find a lead-laden carcass and get lead poisoning. But is individual #3 likely to also get lead poisoning from this carcass? This might depend in part on #14–if she learns where the carcass is from #31 and #5, then this information might get passed on to the others more rapidly. This is the importance of the “connector” or “social broker”–she facilitates the spread of information across the entire network, and this might be the key to understanding who gets poisoned and why.
In truth, we do not yet know whether lead poisoning spreads this way–this is just one hypothesis. The first step is to get these valuable data from the photographs we have and start understanding what the “Facebook of Condors” looks like. This is one way in which your efforts on Condor Watch will help in the larger goal of conserving these magnificent birds. We greatly appreciate your help!!
Integrating other data
The social network analysis is only one of many datasets and analytical tools we will be using to help conserve these majestic birds. From the photographs, we will also be looking at other social dynamics such as social dominance–e.g., are dominant or subordinate birds more susceptible to lead poisoning? For some birds, we are also collecting detailed data on their home ranges using GPS units mounted on their wing tags (you can sometimes see these in the photos). Ongoing studies on physiology and toxicology of lead poisoning are key to understanding the impact of lead on an individual level (see this previous post). These and other data sets will ultimately be used to better understand what factors help or hinder the recovery of the condor population. A really exciting aspect of the Condor Watch project is that it is a true collaboration between behavioral ecologists, spatial ecologists, ecotoxicologists, population ecologists and citizen scientists!
We will continue to post more tidbits on our scientific plans and progress, so please keep checking back!
Condor Watch has a growing group of thousands of enthusiastic, hard-working volunteers. These volunteers have already produced over 150,000 classifications of images. We have volunteers from every ice-free continent, hailing from over 130 countries!
We have two fabulous and incredibly energetic moderators: Wreness and ElisabethB. Many thanks to both for their hard work monitoring posts and keeping the site fun and productive while both doing mind-blowing numbers of classifications!!
We are pleasantly surprised at the proportion of images that have multiple readable tags, which are yielding good data on social structure and the amount of time different types of individuals use feeding stations.
We expected to see other species besides condors, but we have been amazed by the frequency of other scavengers and the breadth of species seen – including large groups of coyotes, as well as mountain lions, bears, golden eagles, and wild pigs. We will be quantifying carcass use by scavengers so please do hashtag these ‘other’ species you see.
The first few months have not been without some website problems and annoyances, as our volunteers have helped us discover! We will be deploying a series of site updates today that should address many of these issues. Here’s a rundown of the fixes/upgrades:
- Ravens! We have heard the cries of despairs. We do want to know how many ravens are present at carcasses but we confess, we just didn’t realize how tedious it would be to mark large unkindnesses of ravens (how fitting a term for a group of animals) in the same manner that condors are marked. We are happy to announce that marking distance to carcass for ravens is NEVERMORE!
- Carcass/scale marking: We have now removed the marking of scales, and only ask that you mark carcasses. We have included a section in the field guide on the best way to do this.
- Back button: Many have reported that it is too easy to mistakenly press “all animals marked”. To try and stop this from happening we have relocated this button so that it appears under the image being classified.
- Mis-identifications and unknown birds. We have struggled to get the code linking tag information to bird ID working seamlessly, and the site still occasionally reports the wrong bio, or no bio at all. We have added some extra tools behind the scenes to help us troubleshoot this, and we will eventually conquer this problem. However, we want to be very clear for anyone worried about how this affects our science–it doesn’t! We have a complete record of all tag data that each volunteer enters and the science team is assigning bios and assessing consensus using a separate process.
We’ve been posting interesting Condor Watch images and general news about condors to Facebook and Twitter several times a week. We’ve heard feedback that there are still people who are not on Facebook, and so to reach the entire community, we’ll also be posting these to this blog as Condor News and Project Updates.
Finally, there are many places to find more help:
The Field Guide: we’ve added clarifying instructions on how to enter wing tag information, how to enter other species, and how to distinguish turkey vultures from condors
Thanks to our volunteers the world over for their hard work and enthusiasm, which is making our site a success and is making a difference for California Condors! Please keep helping us at www.condorwatch.org