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Condor Cam

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Condor Chick Ready to Fledge

The Condor Cam caught Su'nan perched on the ledge.

Su’nan is perched on the barrier between the nest box and the roost area.

As many Condor Cam viewers have experienced, the rearing process for a California condor can be long and slow. It makes sense, though, for a condor to develop so slowly. She has lots of growing to do! When our chick, Su’nan, hatched on April 29, she weighed approximately 6.3 ounces (180 grams). When she reaches her fledge weight of 17 pounds (8 kilograms) or more, she will have increased her hatch weight by 44 times! In contrast, I have only increased my birth weight by 19 times.

On August 27, at 121 days of age, Su’nan took her most recent step toward leaving the nest: she jumped up onto the barrier between her nest box and the adjoining roost area. She quickly hopped back into her nest, but that’s okay. There’s no hurry to fledge, or leave the nest, just yet. Her feathers still need time to fill in. Hopping up and down from the barrier will exercise her muscles, as well as improve her balance. She has since started hopping into the roost area on the other side of the barrier. Here, she can warm herself in the sun, if she chooses.

Su'nan stretches out one of her fast-growing wings.

Su’nan stretches out one of her fast-growing wings.

While out in the roost, she can also rest or sleep in the shade, perch with her parents (if they are not perched out in the flight pen), or step out to the roost ledge to soak up the sun’s rays for the first time. The ledge is about 8 feet (2.4 meters) from the ground—high enough to make the parents feel comfortable and secure in their nest but not as high as a condor nest in the wild. Su’nan may get near the edge, but she will be cautious in doing so, so she doesn’t teeter off. It is natural for condor chicks to explore and exercise on the edge of their nest cavities. Rarely do they fall out; in 32 years of raising California condors here at the San Diego Zoo Safari Park, we have never seen a chick fall from its nest area.

The next step of Su’nan’s development will be to fledge. When she is ready, she will jump off of the nest ledge. She will either slow her fall to the ground below the ledge or fly to a nearby perch. We consider her fledged when she can get up on a perch by herself. The youngest we have seen a condor chick fledge here at the San Diego Zoo Safari Park is 123 days old. Sometimes chicks have waited until over 165 days. It all depends on the chick.

She's made it to the other side!

She’s made it to the other side!

The parents tend to be very vigilant during this phase of their chick’s development. It could appear overprotective to us, but keep in mind that they have invested an entire breeding season and lots of energy into this one chick. It benefits them greatly to make sure that their sole offspring is safe, healthy, and strong. They usually don’t coax or pressure their chick to leave the nest; on the contrary, we have seen parents make sure a chick doesn’t stray too far from the nest if it’s not ready yet. The parents will usually perch and/or roost near the fledgling.

They also will join her when she finally starts going to the feeding area of the flight pen. Most of the time, though, they will push her aside and eat first, feeding her when they are done. In condor culture, the bigger, more dominant birds usually eat first, while the subordinate birds wait their turn. The earlier Su’nan learns this from her parents, the better she will assimilate into a wild population after she is released. Don’t worry: Towich and Sulu won’t let Su’nan starve. They will continue to feed her even when she is out in the flight pen. Eventually, she will eat more and more on her own.

Her foster parents keep her company in the roost area.

Her foster parents keep her company in the roost area.

Depending on Su’nan’s development and activity levels, we will try to switch the Condor Cam view from the nest box/roost area to the flight pen. You’ll be able to see the roost area, most of the perches in the pen, the feeding area, shade areas created by plants, and the pool, where she can either drink on her own or bathe (one of my favorite condor activities to observe!). The view will be wide, so detail will be harder to discern. Also, we do minimal maintenance in the pen once the chick is large enough to look over the nest box barrier. So the pen has lots of plant growth and dried food (animal carcasses) in it. We limit our activities in/near chick pens so as not to expose the chick to humans, thus desensitizing her to our presence. We have found that chicks raised in isolation from humans tend to be more successful once they are released to the wild. The flight pen won’t look as nice as an exhibit you might see at the Zoo or the Safari Park, but Towich and Sulu prefer it that way, if it means we stay away from their precious chick!

Thanks so much to all of our faithful and dedicated Condor Cam viewers. Soon, your support and devotion will be rewarded when our “little big girl” spreads her wings and takes that next step. Rest assured, though, that Su’nan’s story will be far from over!

Ron Webb is a senior keeper at the San Diego Zoo Safari Park. Read his previous post, Condor Chick Foster: Name is Chosen!

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Condor Chick: Name is Chosen!

Su'nan peeks over the ledge at Dad, left, and Mom.

Su’nan peeks over the ledge at Dad, left, and Mom.

The naming poll results are in: the name of the California condor chick featured on San Diego Zoo Global’s Condor Cam is Su’nan, Chumash for “to continue to, to keep on”! She is now over 90 days old and is starting to get her big-bird feathers. Some of the first feathers that start to grow are the wing feathers.

It is easy to see the feathers growing through Su’nan’s down: the down feathers are gray, but the new flight feathers are black. The long feathers that grow from the tip of the wing are called primary feathers, and the feathers from the wrist to the armpit are secondary feathers. Primary and secondary feathers are the giant feathers that make the California condor’s wing so large and impressive. An adult can have a wingspan of up to 9.5 feet (2.9 meters)! We are estimating Su’nan’s wingspan to be around 5 feet (1.5 meters) right now, between the size of a red-tailed hawk and a bald eagle. Her tail feathers are also starting to grow. They’re a little harder to see on camera, but you should be able to spot them soon.

After the wing and tail feathers fill in, the feathers on Su’nan’s back will start to grow, as well as the small feathers on the top of the wing, called coverts. Even though many new, black feathers will be covering parts of her body, she will still have lots of gray down showing, making it easy to differentiate her from her parents. Eventually, her light-colored skin will turn dark gray or black and be covered with fine, fuzzy feathers, but this won’t happen until well after she leaves the nest. Her skin will stay dark until she reaches maturity at 6 years, and it turns pink-orange, just like her foster parents’, Towich and Sulu.

Su’nan had her second health exam on July 14, during which our veterinary staff administered her second, and final, West Nile virus inoculation. A blood sample was obtained, and she weighed 11 pounds (5 kilograms), over half of her projected adult weight. Even though our little girl is getting big, she still has room to grow!

The adult condors are fed four days a week. The other three days they are fasted. They often don’t eat every day in the wild, sometimes fasting for up to two weeks, so our nutritionists recommend not feeding them every day to prevent obesity and food waste. Their diet, depending on the day, can consist of rats, rabbits, trout, beef spleen, or ground meat. We offer 2 to 3 pounds (1 to 1.3 kilograms) of food per bird per feeding day. When the condors are raising a chick, we offer extra food every day: 1 rat, 1.5 pounds (0.7 kilograms) of beef spleen, 1 trout, and 0.5 pounds (0.2 kilograms) of ground meat. They don’t end up feeding all of this food to Su’nan, but we want to be sure they have enough for the growing baby. It’s difficult to calculate exactly how much food Su’nan is eating each day, but we estimate that she could be eating 1.5 to 2.5 pounds (0.7 to 1.1 kilograms) of food per day.

Many Condor Cam viewers have seen some rough-looking interactions between Su’nan and her parents. What may have been happening was a form of discipline. As Su’nan has gotten bigger, her begging displays and efforts have gotten more vigorous, which can be bothersome or problematic for parents wanting some peace and quiet. They have two ways to make sure Su’nan does not cause too much trouble while begging: leave immediately after providing food, which is what we’ve seen a lot of on Condor Cam, or discipline the unruly chick. This discipline can come in the form of the parent sitting or standing on Su’nan, or the parent may nip or tug at her. Either of these behaviors results in Su’nan being put in her place by the dominant bird in the nest, thus ending the undesired behavior. Sometimes, this discipline may occur before the chick acts up. Be mindful that this is perfectly normal for condors to do, even though it would be cruel for us to treat our own babies like that! When condors fledge, or leave the nest, they need to know how to interact with dominant birds at a feeding or roost site. This seemingly rough behavior from the parents will benefit Su’nan later when she encounters a big, unrelated bird that might not be as gentle.

Su’nan hasn’t jumped up on the nest box ledge yet, but she may soon. Stay tuned for our next blog that will discuss this big milestone! Also, we would like to thank all of the Condor Cam viewers for their patience while we had camera difficulties for a week or so in July. Our technician replaced the power supply and the camera with very minimal disturbance to the condor family.

Ron Webb is a senior keeper at the San Diego Zoo Safari Park. Read his previous post, Condor Chick Fostering: First Exam.

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Condor Cam Chick Needs Name

Name the Condor ChickHatched on April 29, a small condor chick emerged into the world observed closely by animal care staff at the San Diego Zoo Safari Park. Adding to the more than 180 condors hatched at the Safari Park since the breeding program began in 1982, the little chick was placed with adult condors Sulu and Towich so they could raise it to adulthood. Its growth has been watched by thousands of people through a live Condor Cam placed in the nest box. Now animal care staff are asking these interested watchers to help choose a name for the young female bird.

Viewers can go online at http://bit.ly/condorname to vote for one of five suggested names. In keeping with the tradition of the condor program, the names have been selected from the Kumeyaay language. The name receiving the most votes will be used for the chick for the rest of its life. Voting closes at end of day on July 20.

“California condors are an important native species in the western United States and hold a special place not only in the ecosystem but in the culture of the people native to this area,” said Michael Mace, curator of birds at the San Diego Zoo Safari Park. “By giving condors names from the Kumeyaay language, we hope to honor the role of condors in human culture throughout history.”

At more than 2 months of age, the condor chick is covered with fluffy, gray feathers and is still closely cared for by its foster parents. The young bird will continue to grow and mature over the next couple of months until its flight feathers grow in and it is ready to leave the nest. Animal care staff at the Safari Park hope that the chick will be able to take its place among the wild populations that have been released in California, Arizona and Mexico.

CONTACT: SAN DIEGO ZOO GLOBAL PUBLIC RELATIONS, 619-685-3291

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Condor Chick Fostering: First Exam

Boy or girl? We'll find out soon!

Boy or girl? We’ll find out soon!

On Thursday, June 12, 2014, the California condor chick you’ve been watching on Condor Cam received its first health exam. The goal was to obtain a blood sample for our labs, administer a vaccine for West Nile virus, inject a microchip for identification, and weigh the chick.

The first step in this process is to separate the parents from the chick. Of course, the foster parents (father Towich and mother Sulu) don’t want any invaders in the nest and do their best to defend the chick and keep it safe, as all good parents do. Adjacent to the flight pen, we have a shift pen, used to safely and calmly move large or dangerous animals from one area to another. We offer all of the condors’ diet in the shift pen, so Towich and Sulu are very comfortable entering the shift pen for every meal. We shifted Towich into the pen and kept him there until after the exam. From his shift pen, he cannot see the nest area, so he was unaware that we were even in his nest, thus keeping him very calm. He ate and waited patiently until he had access back into his flight pen.

Sulu was not shifted but instead was able to see us go into her nest. We posted one keeper in the nest entryway to keep Sulu out, while another keeper entered the nest and covered the little chick with a towel. This is the first time that the 45-day-old chick had ever seen a person and was understandably nervous and defensive, hissing and lunging at the intruder. Once under the cover of the towel, the chick could not see and calmed down. It was then brought into the adjoining vestibule where our veterinarian staff was waiting.

First, the veterinarian obtained a blood sample from the chick’s leg. This sample was sent to the lab to make sure that the chick is healthy. Also, our geneticists can determine if it is male or female from this sample. Next, a vaccine for West Nile virus was administered and a microchip was injected under the chick’s skin. The veterinarian did a quick health assessment, checking the chick’s eyes, nares (nostrils), beak, feet, legs, wings, and abdomen. Lastly, we weighed the chick to make sure it was growing on schedule.

While the exam took place, a third keeper was able to enter the nest to clean the camera domes and make sure there were no hazards in the nest cavity. The whole exam, from capture to release, took about 10 minutes.

Once the exam was over, the chick was returned to the nest and Sulu was allowed to approach and check on her baby. The chick was rightfully disturbed by this process, despite our best intentions to minimize stress. Although we feel bad that the chick was so nervous, it is actually good that it was not comfortable in our presence. We have to keep in mind that we don’t want the young condor to become accustomed to or feel reassured by humans; we want it to be a wild condor, uninterested and wary of humans, so that it may someday fly free in California, Arizona, or Mexico. Condors that show an affinity for humans seldom survive in the wild.

For several minutes, the chick showed a defensive posture, hissing at everything it saw, even its mother. Sulu slowly approached her chick and calmly preened it, eventually soothing it. That is the reason we shifted only one parent; we wanted the other parent present to calm the chick after the exam. After only about two minutes, the chick was showing proper begging behavior, resulting in a feeding session from Sulu. With everyone appearing calmer, Towich was let out of his shift pen. About five minutes after that, he approached the nest to peek in on the chick and to perch in the adjoining roost area.

So far, the health exam looks to have been successful. Hopefully, the blood work will show that the chick is healthy. The veterinarian’s initial inspection revealed that the chick’s eyes and nares were clear, the feet, legs, and wings were solid, and its vitality was very strong. The chick weighed 6.8 pounds (3.10 kilograms) and was about the size of a bowling ball. We hope to receive the sex results from the Genetics Lab soon. When we do, we’ll let you know if the chick is a male or a female.

Ron Webb is a senior keeper at the San Diego Zoo Safari Park. Read his previous post, Condor Chick Fostering: 30 to 45 Days.

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Condor Chick Fostering: 30 to 45 Days

The growing chick has lots of feathers to play with.

The growing chick has lots of feathers to play with.

At a little over 1 month of age, our California condor chick should weigh around 4.5 pounds (2 kilograms) (see previous post, Condor Chick Fostering: 1 Week to 1 Month). The foster parents, Towich and Sulu, have started leaving the chick alone overnight, sleeping near the nest. If the weather is still cool or it’s raining, the parents may brood overnight until the weather improves. Even though the parents are increasing their time away from the chick, they remain VERY vigilant and protective of their nest and, especially, their chick. Some field biologists have even seen wild condor parents chasing black bears away from the nest area!

Up until now, the chick has been scooting around the nest on its tarsal joints—we call it the tarsal crawl. It’s not uncommon, at this age, to see the chick standing all the way up on its feet, teetering around the nest, holding its wings out for balance. As its legs get sturdier, the chick may even approach the parent, begging for food. The wing-begging behavior we’ve been seeing gets more pronounced: lots of wing-flapping, head-bobbing, and trying to position itself in front of the parent.

It is possible that the parents, who are offering larger quantities of food per feeding session, might be providing a small amount of fur/hair in the chick’s diet. (Part of the adults’ diet includes mammals, like rats and rabbits.) Condors can digest just about every part of the animals they eat, except for fur. This fur accumulates in the digestive tract and is eventually regurgitated as waste. We refer to this as casting. A condor’s cast is composed of predominantly fur, whereas a cast from an owl has fur and bones; owls can’t digest bones, but condors can. We have seen condor chicks cast hair pellets as young as three weeks of age. When the chick casts, it throws its head forward several times, mouth open, until the pellet is ejected from its mouth. It can look like the chick is in trouble, but it is perfectly normal, and good for the chick.

At 45 days of age, or around June 12, the chick will get its first health exam. We will obtain a blood sample for the lab to make sure it is healthy and to determine if the chick is male or female. Also, during the exam, we will weigh the chick—it should weigh between 7.7 and 8.8 pounds (3.5 and 4 kilograms)—and inject a transponder chip as a form of identification. It’s the same kind of chip you can get for your dog or cat. Most importantly, this exam allows us to administer a vaccine for West Nile virus, a disease that originated in Africa and was accidently introduced to North America by humans. North American wildlife, including condors, usually doesn’t have a natural immune response to West Nile virus, so we are trying to give the chicks as much of a head start as we can.

This exam will be the first time that the chick will see humans, so it will naturally be disturbing for it. We try to be quick (9 to 10 minutes) to minimize the disturbance. Additionally, we will keep the chick covered with a towel to reduce its exposure to humans and to provide it a bit of security. Towich and Sulu are usually away from the nest when we perform the procedure, to keep them as calm as possible as well. We don’t want the chick to become accustomed to or feel reassured by our presence; we want it to be a wild condor, uninterested and wary of humans, so that it may someday fly free in California, Arizona, or Mexico.

The chick will look very large at this age compared to how big it was at hatch, but remember that it is still less than half of its adult weight. There is much more growth and fun to come on Condor Cam!

Ron Webb is a senior keeper at the San Diego Zoo Safari Park.

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Condor Chick Fostering: 1 Week to 1 Month

The condor chick is staying cool today!

The condor chick is staying cool today!

At two to three weeks of age, the real fun of condor chick-viewing begins! (See previous post, Condor Chick Fostering: Week 1) Our Condor Cam chick is getting bigger, weighing between 17 and 42 ounces (500 and 1,200 grams), and can often be seen poking its head out from under a parent’s wings. Towich and Sulu might be spending less time sitting on their foster chick, weather permitting, leaving it unattended for longer periods of time, possibly 30 minutes or so. Never fear! They are nearby, often just out of the camera’s view, just a few feet away.

It is usually easier to observe feeding behavior at this age, as well. Sulu or Towich stand a little to the side of the chick now, so you may catch a glimpse of food actually being transferred from parent to chick. The chick’s crop may be visible as a bald patch of skin when it’s full. It is between the size of a golf ball and a tennis ball. You will also witness a very common behavior called wing-begging; the chick is begging for food, flapping one or both of its stubby little wings and bobbing its head excitedly. This behavior can persist until after the chick fledges, or leaves its nest, at four to five months.

The chick hatched wearing a fluffy coat of white down feathers. The main function of down is insulation; it can either keep a bird cool or warm, whatever its body needs. At this stage, the chick’s white down is starting to transition to gray. Sometimes this can make the chick look dirty or scruffy, but it is still as healthy as it ever has been. It and the parents are frequently grooming the feathers to make sure they are working the way they should be. These dark feathers also help the chick blend in with the substrate and the nest cave walls, since Towich and Sulu are not covering the chick as much as they were.

You may have noted that the chick looks like it has scabs on its head/neck or has wounds on its body, matting its down feathers. This is actually regurgitated food stuck to its face or body. Feeding can be quite exciting for the chick, and some food doesn’t always end up in its mouth! The chick obviously can’t take a bath at this age, but the food will dries up, gets crusty, and flakes off, a major benefit of having a bald head! Anyone who has seen the adult condors eat on exhibit at Condor Ridge at the San Diego Zoo Safari Park or Elephant Odyssey at the San Diego Zoo can attest to the condors’ ability to keep clean after a messy meal. Also, the presence of flies in the nest is nothing to worry about. Keep in mind that condors are carnivores, feed their chicks via regurgitation, and nest in cavities (caves, crevices, etc.) that are often sheltered from the wind. All of these components add up to a very comfortable environment for flies as well as condors. Yet condors have excellent immune systems and are only mildly annoyed by the flies!

As of this writing, our Condor Cam chick is a little over two weeks old. At three weeks of age, it can start to thermo-regulate, or control its own body temperature. This is when its devoted foster parents can start leaving the chick on its own during the day. Depending on the ambient temperature, the chick may be seen shivering or panting in an effort to warm or cool itself. Also, on warm days, the chick may inflate the air sacs in its chin and neck to cool down. Air sac inflation can also occur after a particularly filling meal. Often, Sulu or Towich may spend time in the nest with the chick, but they may not necessarily sit on the chick.

The chick is more mobile, scooting around the nest on its haunches, or tarsal joints. We refer to this as a tarsal crawl. It’s not quite standing up on its feet, but it can move about, following the parents and investigating different parts of the nest. You may see the chick start to gather items (feather, scraps of old food) from around the nest and move them to one corner. The chick likes to sit or sleep on this pile and play with the different items. These feathers and old food scraps are often brought to the nest by the parents. Birds replace their feathers molting, similar to when mammals shed their hair/fur. We don’t know if the parents are bringing these items to the nest specifically for the chick or if it’s just happenstance, but the chick loves to investigate and play with them!

As the parents start leaving the chick alone for longer periods of time, it will be easier to watch the chick when it sleeps. Just like all growing youngsters, condor chicks sleep A LOT. With longer legs and gawky bodies, they often are sprawled out, wings askew, in odd positions when they sleep. Do not worry! The chick is perfectly fine.

At approximately 1 month of age, the chick should weigh around 4 pounds (1.8 kilograms). The parents may start leaving the chick alone overnight, sleeping near the nest. If the weather turns cool or it’s raining, the parents may continue to brood overnight. Even though the parents are increasing their time away from the chick, they remain VERY vigilant and protective of their nest and, especially, their chick.

Happy viewing, and thanks so much for your support!

Ron Webb is a senior keeper at the San Diego Zoo Safari Park.

1

Condor Chick Fostering: Week 1

Towich dutifully sits tight.

Towich dutifully sits tight.

The San Diego Zoo Safari Park’s newest California condor chick hatched on April 29, 2014, weighing around 6 ounces or 180 grams (see post Fostering Condor Chicks). The hatching process can be grueling, so afterward, the chick usually rests a lot and is brooded—or sat on—by the parents. We often call this sitting tight. The parents are providing protection and warmth, especially while the newly hatched chick is drying off. With the chick being weak and wobbly, it often is hard to feed, but that is okay. The chick is getting nutrients from the yolk sac that it absorbed into its belly just before hatching.

After about a day, the chick can hold its head steady, and the parents then start providing food. They eat food that we offer out in the flight pen and then bring it to the chick in their crop (a bulge in their esophagus where they can store up to 3 pounds of food). The food is regurgitated for the chick, providing a warm and nutritious meal. Mmmmmmm! The diet we provide varies, depending on the day, but it can include rabbits, rats, trout, beef spleen, and ground meat. While the chick is very young, it is often difficult to witness a feeding on Condor Cam, since the parents are standing directly above the chick, blocking the camera’s view. If you see the parents slightly bobbing their heads while standing over the chick, feeding is occurring. Feeding sessions are fairly short for small chicks, since their crops are only about the size of a lima bean.

Condor Cam zoomed in on the doting father this morning.

Condor Cam zoomed in on the doting father this morning.

Both the male and female California condor provide care for the chick. This drive is very strong, and it’s not uncommon to see the parents vying for time with the chick, especially immediately after hatching. This happens in the form of leaning into each other, pushing one’s way onto the chick; scooping the chick from one parent to the other; or nipping at neck skin or tugging at feathers to get the other parent to move. Usually, one parent acts more dominantly and controls the interactions a little more than the other parent. This time, father Towich took this dominant role. Other years, we’ve seen Sulu take this role. We interpret this periodic shift in dominance, and the other bird’s acceptance of this shift, as a very good trait in a condor pair. As time passes after hatch, they settle into a routine, and the nest exchanges become much calmer.

Sometimes Condor Cam viewers are concerned about the number of times that the chick gets stepped on by the parents. In many species, ranging from hummingbirds to elephants, babies get slightly squished by the parents. Usually, it’s just a minor misstep, and the baby lets the parent know with a brief vocalization. Condors are no different or no more fragile. They are very hearty little chicks!

As young as 4 days of age, we have seen chicks sifting through the sand in the nest, picking up items on their own. We’ve even seen chicks swallowing small pieces of their eggshell for dietary calcium.

At the end of the condor chick’s first week of life, it weighs around 10.5 ounces (300 grams). It is getting much stronger but is not venturing around the nest very much yet. Coordination is improving, and we can witness social interactions with the parents: nibbling, preening, and nuzzling. Every once in a while, you may see the chick quivering, almost like it has the hiccups. It is actually vocalizing. Condors don’t have a true voice box or syrinx like other birds, but they can make crude, primitive vocalizations. Adults may grunt, wheeze, or hiss. Chicks can make a high-pitched, scraping squawk, usually when begging or when out from under the parents for too long.

The next few weeks of development are very exciting, not just for the condor family but for any of us watching on the Condor Cam. Stay tuned!

Ron Webb is a senior keeper at the San Diego Zoo Safari Park.

3

Fostering Condor Chicks

Towich carefully keeps his new chick warm underneath him.

Towich carefully keeps his new chick warm underneath him.

Sometimes things go exactly as you plan. Sometimes Fate throws you a big curveball, forcing you to change that plan. As our Condor Cam viewers know, the egg that was going to hatch on Condor Cam this year under our experienced parents, Sisquoc and Shatash, died unexpectedly at the end of its incubation period on March 16 (see Condor Egg Loss). As a result, we moved the Condor Cam to a different nest in our Condor Breeding Facility at the San Diego Zoo Safari Park so that you could watch another pair, Towich and Sulu, hatch and rear a chick.

The male is Towich (pronounced TOH-witch) and the female is Sulu (SOO-loo). Towich is wearing yellow wing tags, numbered 35. Sulu is not wearing any tags. Towich hatched at the Los Angeles Zoo, one of our valuable partners in the California Condor Recovery Program, in 1996. He was released to the wild in Southern California in 1997 but was returned to captivity when he started showing interest in humans. More than likely, he was fed by people when he was young, causing him to lose his wariness of them. He is no longer suitable as a release bird. Towich’s story serves as an essential reminder that when viewing condors in the wild (or any wildlife, for that matter), it is of the utmost importance that we do not feed them or approach them too closely. Getting that extreme close-up picture or having the thrill of feeding a wild animal is not worth having the condor removed from the wild.

Sulu hatched at the Safari Park in 1990, and she has lived here with us her whole life. Towich is her second mate. She was separated from her first mate in 2000, when it was determined that she and Towich were a better genetic pairing. The pairing process in a breeding program can sound a bit clinical, especially in a species such as the California condor, whose population dropped to only 22 birds in 1982, but we have to be very careful who gets paired with whom in order to maintain as much genetic diversity as possible. Despite the lack of romance in being paired together, Towich and Sulu have developed into an awesome couple. They seldom squabble over food; they often perch near each other in the flight pen; they have excellent nest exchanges when incubating eggs or brooding chicks; and they seem to like to sit or lay down together, along with their chick, in the nest box or the roost.

The egg that Towich and Sulu produced this year was expected to hatch here at the Safari Park sometime around mid-April, but plans change. It was determined that their egg would be sent to the Los Angeles Zoo, along with another of our eggs, and that we would receive two Los Angeles Zoo eggs to hatch here. The U.S. Fish & Wildlife Service, which oversees the California Condor Recovery Program, analyzed the free-flying condor population and decided that the two eggs produced at the Safari Park would be good candidates to eventually release in California and that the two Los Angeles Zoo eggs would be better to release at the site in Baja California, Mexico. We were asked to raise the two chicks destined for Mexico, hence the exchange with the Los Angeles Zoo.

Sometimes it can get confusing trying to plan (or explain!) egg exchanges, but it’s all to ensure that we are maximizing genetic diversity among the California condor population, not just in the breeding facilities but at the release sites as well. We received good news from the Los Angeles condor keepers that Towich and Sulu’s egg successfully hatched on April 19, 2014!

Of the two eggs that we received from the Los Angeles Zoo, one hatched on April 12 under two birds familiar to Condor Cam viewers: Sisquoc and Shatash. After their original egg failed to hatch, we kept them sitting on their fake egg (a dummy egg) to keep them in breeding mode, just in case another egg needed to be hatched. Normally, condors incubate their egg for about 56 days until it hatches. If it does not hatch for any reason, they will sit for a little while longer before abandoning the egg. Sisquoc and Shatash were very attentive and sat for a whopping 80 days until their foster egg hatched! The chick is doing very well and is growing quickly, thanks to Sisquoc and Shatash’s devotion.

The second Los Angeles egg was fostered to Towich and Sulu. We were hoping that it would hatch live on Condor Cam, but to follow this year’s theme, plans changed. The embryo in this egg wasn’t positioned quite right in the shell, making hatching on its own very unlikely. We cut a hole in the shell, allowing the chick to breathe more easily. When it looked strong enough, we exchanged the dummy egg in Towich and Sulu’s nest with this newly pipped egg. They bonded immediately to the egg, tending to it faithfully. The next day, on April 29, while they were eating in the pen, we sneaked into the nest to break off some of the shell, simulating a natural hatch. After we were able to evaluate the chick’s health, we carefully placed it back in the empty shell and set it back in the nest. Within 30 minutes, Towich and Sulu removed the chick from the shell and started taking care of it. So far, the chick looks great and can now be seen on Condor Cam!

Fostering is a common technique used in avian breeding. The parents usually accept the new egg and hatch it and raise the chick as if it was their own. This process is very valuable in the California Condor Recovery Program, increasing the opportunities to release parent-reared birds to the wild. Also, fostering allows pairs that lose their eggs, for any reason, to successfully raise a chick together. Repeated success in a nest strengthens the bond between the two parents. Too many failures often lead to the pair squabbling and ultimately dissolving their bond.

Have fun watching Towich and Sulu raise their foster chick this season. They are great parents and should provide you with lots of fun viewing opportunities! We will offer blog updates explaining the chick’s growth process and will try to answer any questions you may have.

Ron Webb is a senior keeper at the San Diego Zoo Safari Park.

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Condor Egg Fails to Hatch

This dummy egg looks just like a real California condor egg and serves as a placeholder.

This dummy egg looks just like a real California condor egg and serves as a placeholder.

As keepers, we often have the privilege to witness or even help usher in a new hatch or birth into the world. Of course, working alongside our excellent veterinary staff, we provide assistance and supportive care to maximize survivability, but sadly, sometimes it isn’t enough. We experienced this recently at our California condor breeding facility at the San Diego Zoo Safari Park when one of our condor eggs failed to hatch. This egg was expected to hatch under our experienced Condor Cam parents, Sisquoc and Shatash, who for the last two years have raised their chicks, Saticoy and Cuyamaca, under the watchful and adoring eyes of thousands of their fans. Saticoy is now flying free in Southern California, and Cuyamaca was recently sent to Arizona to be prepared for release there.

We usually remove the egg after it is laid so we can artificially incubate it and monitor its development without disturbing the very protective parents. While we are caring for the real egg, we give the parents a fake egg (called a dummy egg) to incubate. This dummy egg serves as a placeholder until the real egg is ready to hatch; without it, the parents would not accept the real egg when we would try to replace it in their nest.

While we were caring for Sisquoc and Shatash’s egg, we weighed it daily to track its weight loss, and we candled it periodically to monitor development inside the shell. During incubation, we noticed that the embryo was slightly in the wrong position to hatch—a malposition. Some malpositions are lethal or need our help to hatch successfully. This embryo’s malposition was not extreme and would not normally need our assistance. What was more concerning was the condition of the membranes surrounding the embryo: loose and saggy when they should have been taut. Concern grew that these membranes would cause difficulty in breathing for the embryo once it moved into the egg’s air cell to begin pulmonary respiration. The loose membranes could adhere to the embryo’s nostrils, suffocating it.

Despite 24-hour care from our keepers and a valiant effort from our veterinary staff, the embryo stopped breathing partway through the hatching process on Sunday, March 16, 2014. The egg was expected to hatch around March 20. The embryo and egg are now at our Pathology Lab; hopefully, we will have more information regarding the cause of death.

Egg mortality is highest at the beginning and at the end of the egg’s incubation period. Sometimes there can be a genetic issue causing the embryo to stop developing. Sometimes the egg can get too hot or too cold during incubation, the egg can get jostled, humidity can be too high or too low, etc. Despite setbacks such as this, our “hatchability” rate at the Safari Park is still very high at over 85% success, much higher than wild eggs that have to contend with nest predators, competitors, and a lack of veterinary support.

So, what’s next for Sisquoc and Shatash? They are still incubating their dummy egg perfectly and are being considered as potential foster parents if another condor egg needs to be parent-reared. They will still sit on the dummy egg, even after the due date of their original egg, but only for about a month or so. After that, they will start to tend to the egg less. We see this behavior in birds that are incubating an infertile egg or an egg that died during incubation. If another condor egg needs to be foster-reared, we can return that egg to their nest, and they will hatch it and raise it as their own. Their drive to care for an egg/chick is so strong that they don’t know or care if it’s not their egg. If another egg doesn’t need fostering, we will remove the dummy egg from their nest. They will then shift from nest-caring duties and spend more time in their flight pen. It may seem sad, but that is what happens to wild birds whose eggs do not hatch.

What’s next for Condor Cam? We have moved the camera to a different nest to show you another of our awesome condor pairs, Sulu and Towich, whose egg is due mid-April. Stay tuned for a blog introducing the new pair.

Thanks so much for all of the comments and condolences regarding the loss of Sisquoc and Shatash’s egg. There are still 30 other California condors at the Safari Park that need us to give them the best care we can. With hope, luck, and your support, we can continue to maximize success for these magnificent birds!

Ron Webb is a senior keeper at the San Diego Zoo Safari Park. Read his previous post,
Egg-citing News on Condor Cam
.

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Egg-citing News on Condor Cam

A precious California condor egg is candled to check on fertility and condition.

A precious California condor egg is candled to check on fertility and condition.

We have good news to report: California condors Sisquoc and Shatash’s egg is FERTILE! Shatash laid the egg on January 22, 2014, and we are expecting it to begin the hatching process around March 18. So, it is approximately one-third of the way through its 56-day incubation period.

Condor Cam viewers have been watching Sisquoc and Shatash take turns caring for and incubating their egg. Well, actually, they’ve been caring for a wooden egg that we refer to as a dummy egg. We use a dummy egg as a placeholder until their real egg is ready to hatch. It’s not as if we don’t trust them with a real egg; on the contrary, they have proven to be very reliable parents! When we place the egg in an incubator, and let the parents sit on a dummy egg, we can more closely and conveniently monitor the egg’s progress and offer any necessary assistance without disturbing the doting parents.

We weigh the egg every day and candle it every few days. When we candle the egg, we hold it up to a bright light that illuminates the interior of the egg, allowing us to see inside. We can monitor blood vessels, membrane development, embryo growth, and movement. As of now, we can see the embryo, which is about 2 inches (5 centimeters) long, moving inside the shell; we can also see its eyes! By weighing and candling during the incubation period, we can make sure that the embryo is progressing normally, and if it isn’t, we can prepare to offer help if and when it is needed.

If all goes well during incubation, and the egg begins the hatching process, we carefully switch it with the dummy egg while the parents are out in the flight pen eating or sunning. They usually don’t even realize we switched eggs on them; they just return to their incubation duties.

As previously mentioned, both the male and female condor take turns sitting on the egg. An incubation bout may only last a few minutes before the parent gets off of the egg and leaves the nest box, or it may sit for the whole day. When the parents take turns on the egg, we call it a nest exchange. Sometimes a nest exchange is immediate: one parent enters the nest, and the other parent gets off of the egg and leaves. Other times, a nest exchange may be long, leaving the egg unattended for up to 30 minutes while the parents are outside eating, bathing, sunning, or socializing. During a long nest exchange, the egg cools down, but not usually enough to endanger the egg, especially with successful and experienced parents like Sisquoc and Shatash. Many times both parents are in the nest area—one may perch in the nearby roost while the other sits on the egg—seemingly keeping each other company.

During nesting season, California condors can be surprisingly territorial and defensive of their nest. Usually, they are very mild-mannered and calm, but when they have a precious egg or chick in the area, they defend it. One of the field biologists in California reported a pair of condors swooping and chasing a black bear away from their nest! Despite being very tough and strong birds, they can be very gentle when it comes to caring for their egg or their chick.

Keep checking in on Condor Cam to follow the progress of Sisquoc and Shatash’s egg and eventual chick!

Ron Webb is a senior keeper at the San Diego Zoo Safari Park. Read his previous post, A New Egg on Condor Cam.