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condor parents

3

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.

5

Condor Chick: 30 to 45 Days

Flashback: This chick, similar in age to Saticoy, was hand-raised in 2001. It was the 100th chick to hatch at the San Diego Zoo Safari Park.

See Ron’s previous post, Condor Chick: 1 to 3 Weeks.

At approximately 1 month of age, California condor chick Saticoy should weigh around 4.4 pounds (2 kilograms). The parents, Sisquoc and Shatash, may start leaving the chick alone overnight while they sleep near the nest. If the weather is still cool or it’s raining, the parents may continue to brood overnight until the weather improves. Even though the parents are increasing their time away from the chick (and hence, Condor Cam), 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 refer to that as a “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 will get more pronounced: lots of wing-flapping and head-bobbing as it tries 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 rats and rabbits. Condors can digest just about every part of the animal 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 as young as three weeks cast hair pellets. 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 44 days of age (April 23), Saticoy will get his/her first health exam at the San Diego Zoo Safari Park. We will obtain a blood sample to make sure the chick is healthy and send a portion of this sample to our Genetics Division, who can determine if Saticoy is male or female. Also, during the exam we will weigh Saticoy 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 at the veterinarian. 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 animals, including condors, usually don’t have a natural immune response to West Nile virus, so we try to give the chicks as much of a head start as we can.

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

Saticoy will look very large at this age compared to how big the chick was at hatch, but remember that this little one is still less than half of her/his adult weight. There is much more growth and fun to come!

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

11

Condors: Big Day Approaching!

The real egg starts to pip!

The big hatch day is quickly approaching, and our devoted California condor parents, Sisquoc and Shatash, have been patiently caring for and incubating their egg that is now beginning the first stage of hatching. And you can help us name this little chick (details below)! Until now, they’ve been caring for a wooden egg that we refer to as a “dummy” egg. We use a dummy egg as a type of 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 artificially incubate the eggs 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. When the real egg is about to hatch, 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’ve switched eggs on them; they just return to their incubation duties, but now their egg is moving and squawking underneath them as they sit.

California condor eggs start the hatching process after 53 to 56 days of incubation. The process can first be seen when the air cell begins to quickly expand. The air cell is a pocket of air at the big end of the egg. Next time you crack open a chicken egg at home, look for the air cell. Once the air cell expands against the embryo’s beak, the membrane of the air cell is pierced, initiating pulmonary respiration. This is the first time the condor chick is breathing air, inhaling more oxygen than can enter through the pores of the eggshell. Consequently, carbon dioxide builds up in the egg. This buildup stimulates the chick to start pushing from inside the egg until the shell is finally broken. A dime-sized bump is raised in the shell. This is called a “pip.”

Once the chick pips the shell, more oxygen can enter the egg, and the chick continues with the hatching process. Blood vessels lining the interior of the egg are shut off and the yolk sac is retracted into the chick via its umbilicus. We obviously cannot see these processes, but we can see the chick breathing, pushing or poking at the pip site, nibbling on shell membranes, and enlarging the pip site by breaking more shell. Every once in a while, we can even hear the chick squawk from inside!

When the yolk sac is fully retracted and the blood vessels are ready, the chick begins to rotate inside the egg. As the chick pushes against the interior of the shell, it rotates inside the egg, breaking the shell as it does so. As you can imagine, this is a very tiring activity for the little chick! The parents don’t break off any new shell for the chick, but they do remove broken pieces of shell. When the chick is almost fully rotated, it starts to push harder inside the egg, resulting in the shell expanding until the top of the egg comes off. This is called “capping.” At this point, the parents help the chick more, removing the capped shell or even pulling the bottom of the eggshell off of the chick. At this point, we consider the chick hatched!

The pip-to-hatch period can vary for each species of bird, but for California condors it can last between 48 and 72 hours. We have seen some parent-hatched chicks take a little longer (about 85 hours) to hatch with no ill effects. If all continues to go well, we are expecting Sisquoc and Shatash’s egg to hatch very soon. You can check on them frequently via our Condor Cam, and maybe you’ll get to see the hatch in progress! This is the first time we have been able to show you the inside of a condor nest and the hatching of chick. We hope you enjoy watching as much as we do.

And to make it that much more exciting, we want to hear your suggestions for a name. There is a catch, though! The name must be submitted in the Chumash language and have a special meaning. For example, Sisquoc was named after the first protected space set aside for this species in 1937, the Sisquoc Condor Sanctuary in Los Padres National Forest. Sisquoc is a Chumash word that means “in the thick tule.”

Submit your condor chick name suggestions by posting them on our Facebook wall at facebook.com/sdzglobal or by tweeting them to us at twitter.com/sdzglobal and using the hashtag #CondorName. Don’t post them here, as we want you to get social and suggest a name on Facebook or Twitter! The deadline for name submissions is March 15. Keepers will pick their favorite three names, and we will give you another chance to get involved by voting for your favorite of the three names selected by keepers from your original submissions. Fun prizes will be awarded, so get creative. And happy viewing!

Ron Webb is a senior keeper at the San Diego Zoo Safari Park. Read his previous post, Condor Cam: The Proud Parents.