Meeting California Condors at Bitter Creek National Wildlife Refuge

Today, my birding group and I went to visit Bitter Creek National Wildlife Refuge in Kern County, California. The refuge, a former ranch, is a grassland habitat located at the foothills of the southwestern San Joaquin Valley. The land has historically been inhabited my the Chumash peoples who have used the area as a major center for trade. The landscape was covered in junipers and native grasses up until European settlers arrived in the late 16th century. Native grasses were taken over by a non-native cultivar, which was then grazed on by the settlers’ cattle. Today, the landscape is primarily this non-native grass and cattle still graze the land, but native plants like junipers and small shrubs still adorn some of the hillsides.

Our main goal while visiting the refuge was to see California Condors (Gymnogyps californianus). As a bit of background (and you can visit this blog post for more info), California Condor fossils date back all the way to the Pleistocene epoch (“the ice age”) at about 10,000 years ago. They historically inhabited much of North America, spanning from coast to coast. As European settlers traveled west a few hundred years ago, they shot, poisoned, captured, and killed condors. Condor range became limited to just the Pacific Coast (Canada to Mexico). By the late 1900’s, condors were put at risk even further, with their range becoming limited to just the mountains of California. The population took a huge hit, eventually decreasing to just 22 condors by the 1980’s. This was because of the use of lead ammunition in hunting.

California Condors are scavengers, meaning they eat carrion (dead animals). Animals that were shot and killed with lead bullets would end up having hundreds of fragments of lead in their bodies. When condors came to eat the carrion, they would ingest the lead. Doing so could then lead to lead poisoning and death if not treated (in time). To keep things simple, biologists realized in the 1980’s that condors were going to go extinct if action wasn’t taken. They started captive breeding programs at three zoos and the last wild condor was captured in 1987. From there, condor chicks were raised in captivity, released into the wild with a wing tag and transmitter, and then extensively monitored by biologists for lead poising. If lead levels in the condor’s blood were too high, they would be taken to a zoo to receive treatment, then released back into the wild if they survived. Every condor was critical for the survival of the species. Today, condors are still extensively monitored, but not as heavily as they were now that there is a stronger population. The species has since been reintroduced to Big Sur and Pinnacles National Park in Central California and parts of Arizona and Utah by biologists.

Okay, now back to Bitter Creek. While there are 91 condors living on the reserve and in the surrounding mountains today (a little over 500 in the world), seeing one was no guarantee. When condor numbers were plummeting in the late 20th century, Bitter Creek National Wildlife Refuge became a critical area for condor recovery, but securing the land was no easy task. The area was formerly a ranch. When the owner of the land wanted to sell the area to building developers, biologists suggested they give it to the U.S. Fish and Wildlife Service instead, knowing that condors used the space for nesting, feeding, and such. After a few years, the government secured the land and intensive condor field work and conservation began. Today, cattle still roam the land and rusted metal machines are strewn across the grasses, but the condors still fly.

My mom and I drove two hours from my house for a once in a lifetime opportunity to potentially see these condors. We joined the other cars on Hudson Ranch Road, just outside the gates to the refuge. We talked with the other birders in my group, watched ravens in the sky, and saw cattle grazing on the nearby hillsides. California ground squirrels scurried across the grassland in front of us. Then all of a sudden, someone excitedly pointed out the first condor: a tiny black dot flying over a mountain ridge that must have been a few miles away! We couldn’t believe our luck! We had only been at the refuge for an hour!

When the park ranger and wildlife biologists arrived, we entered through the gates and made our way to the bunkhouse in our respective vehicles. There, we spotted multiple Western Kingbirds, a Desert Cottontail, a few Western Fence Lizards, and more California Ground Squirrels. A Red-tailed Hawk soaring high up in the sky carried a snake (either gopher or some rattlesnake) in their talons, the snake swaying from side to side as the hawk rode on thermals. The park ranger briefed us on what we were expecting to see and notified us of the potential risks of sudden fires and rattlesnakes (we luckily didn’t experience any of that)! Our eyes couldn’t help but look to the sky as he spoke when three more condors soared in the distance. How lucky were we?

After the briefing, we drove our vehicles along a dirt path to get to our first stop: a now retired pit trap. When condors were being captured for the captive breeding programs, biologists had to well, catch them. They did so with pit traps, a traditional method developed by the Hidatsa Indigenous Peoples to capture eagles along the Missouri River. A pit trap is a shallow pit in the ground covered with woven sticks and leaves. Inside the pit, a biologist would wait to grab a condor’s legs when they came to feed on the provided carcass, usually a stillborn calf. This method for catching condors was somewhat controversial, but that is what condor conservation had come to. In 1987, California Condors became extinct in the wild when the last one was captured at Bitter Creek. Every single condor had to be captured for captive breeding, every last one.

Now, the pit trap is no longer necessary for condor recovery as better, less invasive methods have been developed. The pit has since been filled, but its location is still noticeable; though it has started blending into the landscape quite nicely. Short chains where carcasses are sometimes attached have taken their place. The bones of a donated domestic horse that was used to attract condors at one point lay not too far from the covered pit.

While visiting the pit, two other biologists showed us how radio telemetry works. Radio telemetry is a way of tracking the movements and locations of an animal with a radio transmitter on them. The system is composed of three parts: the transmitter, a radio antenna, and a radio receiver. Many California Condors wear VHF transmitters, which give biologists real time information on the bird’s location. How does it work? Each transmitter worn by a condor gives off a radio signal that is detected by the antenna, which the biologist will have with them. The signal is then converted to a beeping sound by the receiver. The more frequent the beeps, the closer you are to the direction of the bird.

I got to try my hand in radio telemetry, which was super cool! By changing the frequency on the receiver, I was able to listen for a different condor. The biologists use a Yagi-Uda antenna, also simply referred to as “the Yagi”, a directional antenna invented by Shintaro Uda and his colleague Hidetsugu Yagi in Japan in 1926. The multiple parallel resonant antennae create an antenna array that works together as one larger antenna that receives radio waves. Ah, good amount of radio engineering there for a zoology blog! 😉

As I rotated in a circle, I began hearing the beeps: a condor, a wild, free flying condor. By adjusting the gauge on the receiver, I was able to home in on the direction of the bird as the frequency of the beeps increased. Hearing the sound of a condor’s location, you are assured that a species that nearly went extinct is still out there. It was truly beautiful.

Biologists will check in on condors daily by flipping through the frequencies and making sure that the birds are moving around and exhibiting their typical condor behavior. A method known as triangulation can help determine the exact location of a condor. The method involves observing and mapping lines indicating the direction of strong radio signals coming from the condor’s transmitter. The spot where the three lines intersect is the location of the bird. If a condor seems to be staying in the same area and not moving around much, biologists may need to investigate as this could mean the bird is unwell. Motionless “condors” could also be dropped transmitters or attributed to faulty technology. Dropped transmitters, what do you mean? 60% of the condors at Bitter Creek have transmitters placed on their tails. But birds molt their tail feathers, so the transmitter can be dropped and the condor could actually be totally fine.

Not all condors carry VHF transmitters with them tough. Some wear GPS transmitters and others have a combination of the two. It all depends on what data scientists want to collect. Unlike VHF transmitters that provide a condor’s location in real time, GPS transmitters collect this data every 15 minutes or so. The data is then sent to biologists whenever the condor is within range of a cell tower. The transmitters are usually fitted onto the wing tag of the bird.

After visiting the pit trap, everyone entered their respective vehicles and we drove to the condor flight pen. Flight pens are large enclosures that biologists use to trap condors. Some form of bait, usually a stillborn calf, is placed inside the pen. Condors can then enter through a door at their own will, biologists can’t force them inside. Biologists hope to catch as many condors as possible so that they can get a better idea of how individuals are doing. This might include checking for symptoms of lead poisoning, putting wing tags on birds without them, and replacing transmitters for more updated ones. 

When we arrived at the flight pen, there were already six condors waiting on top of the enclosure: five adults and one juvenile. We parked the cars on a hill and from there, we looked down at the pen, the condors probably a only a couple hundred feet away. It was so breathtaking to witness these magnificent birds up so close. My group was so fortunate to have so many condors to view and appreciate as condors at the flight pen is never a guarantee. All six of the condors were tagged. Majority had either black or green tags, the 500s and the 700s. One had a pink tag, an 800, and another a white tag, which in this case was for an 1100 bird. We watched the condors as they meandered about the top of the enclosure. Some showed off their 9.5 foot wingspan by flapping their wings to move short distances. Other socialized in small groups. Some condors would leave the flight pen, soar throughout the canyon, then come back.

Eventually, a condor with an orange tag flew in and walked around the flight pen. This historic condor was 20, formerly know as AC-4. Condor 20, a 42 year old male, was one of the original 22 condors that remained in the wild before they were all brought into captivity by 1987. He was one of the few condors that were able to survive lead poising long enough to be taken in. 20 eluded biologists who needed to capture him for years. He was brought to the Los Angeles Zoo for the captive breeding program and was there for 30 years, where his DNA was used to help increase the population. He was released back to Bitter Creek in 2015 in a historic and awe-inspiring ceremony. After his soft release, 20 soared about the canyon, eventually returning to the nest where he had hatched. It’s amazing how after decades, the bird still knew where he had come from. 

A few people in my birding group actually had the opportunity of witnessing Condor 20’s release. Seeing him again brought back powerful memories for them. We hope 20 will continue to live a happy life back at his home in Bitter Creek National Wildlife Refuge. 

The sun’s intensity increased as we hit high noon. Despite the light wind that made the weather a bit more bearable and of course the condors, everyone was getting hungry for lunch. We said our goodbyes to the magnificent vultures and drove down the road to return to the bunkhouse. Our visit at the reserve was down to its final hour. When we arrived, we explored around the area a bit before heading to the picnic tables. The park ranger led us to a small barn that sat not far from where we would be eating. The dirt floor was littered with sticks, owl pellets, and bones (the past meals of owls and coyotes). The ranger pointed out an active Common Raven nest tucked away in the rafters and an owl nest box that had recently housed Barn Owl chicks.

Also in the barn were dozens of large crates. These crates are used to transport the condors who need immediate medical attention to the Los Angeles Zoo. After watching condors soaring in the sky and socializing on top of the flight pen for hours, you almost forget that they are an endangered species. Seeing these cages made things very real. They brought me back to the reality of the ongoing plight of condors. Yes, they are wild birds, but they are not off the hook. They continue to be extensively monitored and cared for. There isn’t a wild condor out there that doesn’t have lead in their bodies. In humans, the only acceptable lead level is 0µg/dL (micrograms/deciliter). For California Condors, they have to live with levels much, much higher. Any one of them could end up getting severe lead poisoning that causes them to become sick, lethargic, and limp. Any one of them could be stripped from their wild habitats to seek life saving, but invasive, medical treatment because of human actions. Any one of them could die because of a preventable, human-caused issue.

And it’s not that biologists aren’t doing everything they can (they certainly are!) but, you can’t treat every condor for an issue that’s going to routinely show up. They can’t all be treated when the issues caused by lead itself aren’t treated. Poising caused by lead ammunition continues to stand as the leading cause of death in condors, accounting for about 50% of deaths. The survival of the species is dependent on the conversation with hunters to discontinue their use of lead bullets. Many have already switched to condor-friendly ammunition and have encouraged others to do the same, but until everyone makes the switch, one bullet that shatters in a single carcass can still poison the many condors that will come to feed on it. As long as there is lead in the environment, condors will continue to be at risk of dying from lead toxocosis.

Getting to see all these condors in one place was unbelievably special. Only a few decades ago, the species was in such a dire condition that many were certain the species would go extinct. Instead, thanks to the tireless work of wildlife biologist, veterinarians, park rangers, zoos, and the public, California Condors still fly today. Getting to see each and every one of the condors we saw that day was a symbol of teamwork, perseverance, and dedication. Each one was beautiful, a part of the ever unfolding story of the California Condor.

Today, more condors are flying free in the wild than there have been in decades. Progress has been made and more progress is on its way, if we can all work together. If we can all educate ourselves and others about the condor’s story. If we continue to say no to lead ammunition and find condor-friendly alternatives. If the important work done by the condor biologists and conservationists who have paved the way continues to teach and inspire, then we will garner the attention of tomorrow’s condor advocates. If we do all this, the condors stand a pretty good chance in my mind.

Suggested Resources

• U.S. Fish and Wildlife Service- Bitter Creek National Wildlife Refuge
  https://www.fws.gov/refuge/bitter-creek
• National Park Service- Condors at Pinnacles National Park plus a lot of other great resources
  https://www.nps.gov/pinn/learn/nature/condor.htm
• Ventana Wildlife Society- Condor Bios
  https://www.ventanaws.org/my-condor-bios.html
• Condor Spotter- Identify individuals by their wing tags!
  https://www.condorspotter.com
• Check out the free Xplore Condor Recovery Program augmented reality app by TimeLooper! The app is available for Apple and Android devices.
• The Condor’s Shadow documentary- MUST watch!! 😉
  https://vimeo.com/506404783
• Dedicated Zoologist- Check out a past blog post of mine where I talk a lot about condors!
  Volunteering at the L.A. Zoo: California Condor Outreach
• Resources by Morgan– Flyers about condors in PDF form
  A Bit About California Condors
  How to Help California Condors

Sources used for this article

• https://ielc.libguides.com/sdzg/factsheets/californiacondor/taxonomy
• http://trailtribes.org/kniferiver/eagle-trapping.htm
• https://www.npr.org/2006/02/03/5186603/saving-the-california-condor
• https://nationalzoo.si.edu/migratory-birds/what-radio-telemetry
• https://www.flickr.com/photos/usfws_pacificsw/with/14522907345/
• https://www.condorspotter.com
• “The Condor’s Shadow”, a documentary by Jeff McLoughlin

Special Thanks To:

• Susan Gilliland for organizing Los Angeles Birders-Students’ trip to Bitter Creek National Wildlife Refuge
• Daniel Cook (park ranger with the U.S. Fish and Wildlife Service) for leading our tour around the refuge and answering our questions
• Erin (a condor biologist at the refuge) for showing us how to track condors, explaining things to us, and answering our questions
• and to the biologists, veterinarians, park rangers, zoos, and the public for their continued dedication to California Condors