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About Author: Athena Wilson

Posts by Athena Wilson

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Cock-of-the-Rock Ruckus

A male cock-of-the-rock peers at Keeper Athena.

A male cock-of-the-rock peers at Keeper Athena.

If you’ve walked through Parker Aviary at the San Diego Zoo recently, you’ve probably wondered what all the commotion is about. There has been a lot of activity as well as a lot of noise coming out of the mouths of some extravagant and brightly colored birds. At first, most seem to think that the birds are showing some aggression toward each other or are being territorial. However, there’s a different explanation for this activity, and I’d like to shed some light on it for you.

The bright reddish-orange birds with black wings and tail feathers, pale gray wing coverts (feathers on their backs), and arcing crests that extend from the back of their head to their bill, almost concealing their bill, are male Andean cocks-of-the-rock Rupicola peruvianus. The females of the species look quite different, with dull plumage that is an orange-brown color and much smaller crests. They all have strong, hooked bills and powerful legs with very sharp claws. My hands can attest to these sharp claws as I learned quickly to be extra careful when handling them. Once they get their grips on something, they won’t easily let go!

A female cock-of-the-rock gathers nesting material.

A female cock-of-the-rock gathers nesting material.

There are two species of cocks-of-the-rock: Andean and Guianan. They belong to a family of birds known as the contingas, which is an amazingly diverse neotropical family of birds containing 34 genera and 97 species. The Andean cock-of-the-rock is sometimes referred to as the national bird of Peru. The genus name Rupicola means the dweller among the rocks and explains their preferred habitat. Andean cocks-of-the-rock are found in mountainous subtropical forests of the Andes in South America, which are often close to rocky outcrops next to streams. Their diet consists of fruit, insects, and occasionally small amphibians, reptiles, and mice, which make up a significant portion of the diet that is fed to chicks.

The San Diego Zoo is proud to be home to the second largest cock-of-the-rock group in the US after the Dallas World Aquarium, where most of our birds were hatched. You can view some of them in Jungle Trails next to the Children’s Zoo as well as in the Parker Aviary. In Parker, we have six birds: four males and two females. Two of these males are housed in the walk-through side of the aviary to help simulate what happens in the wild. They participate in the display but do not participate in breeding.

One of the unique characteristics of the cock-of-the-rock occurs during breeding season: males gather at communal courtship sites known as leks where they engage in elaborate vocalization, displays, or dances. These gatherings are a form of competition for breeding females and an opportunity for the males to show off their skills. Fifteen or more males may participate in a lek.

A female observes a male cautiously.

A female observes a male cautiously.

Breeding season varies depending on the area but is prompted by the rainy season and will likely continue through February as long as they are stimulated by rain. Therefore, this is the best time of year to watch them display. As you walk through Parker Aviary, you can hear peculiar loud, hoarse grunts, chuckles, squawks, and snapping of bills as males dramatically bow, jump and flap their wings. The displays usually take place on exposed branches and occur more often early in the morning and early in the evening when the light is less intense. This may be related to the bright coloration of the males and vulnerability to predators during the display periods.

At the lek, males may be observed breaking up into pairs and performing confrontation displays. This is when most of the bowing, jumping, and bill clapping occurs, which becomes even more intense when a female approaches to investigate. The advantage of housing four males in close proximity to each other in Parker Aviary is that it provides us with the opportunity to observe these confrontation displays up close.

The female defends her nest when the male gets too close.

The female defends her nest when the male gets too close.

Following mating, the female constructs a concave cup nest of mud and vegetation. Mixing saliva with the plant matter and mud, the nest is built under a rocky overhang, in a cave, or attached to a cliff face. Occasionally, females may nest closely together if the site is suitable; however, they may also be territorial of their nest sites, as our dominant female is of her cave in Parker. A typical clutch contains 2 eggs that are incubated for 25 to 28 days. Females are solely responsible for incubation as well as chick rearing. It takes 42 to 48 days before a chick fledges. Away from lek sites, females are usually alone. Males forage in pairs, but they roost alone at night.

For now, these birds are not globally threatened. Threats in the wild include birds of prey, snakes, and encroachment on the birds’ habitat. A few fortunate visitors to places like Machu Picchu may have had the incredible opportunity to enjoy these birds in their native home. This is on my personal “to do” list. In the meantime, I will continue to enjoy working with them at the San Diego Zoo and be thankful for the privilege to experience such an incredible species. I hope you may also have this opportunity and find it equally rewarding and enlightening.

Athena Wilson is a senior keeper at the San Diego Zoo. Read her previous post, First Flamingo Hatch of 2012.

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First Flamingo Hatch of 2012

Flamingo mother 30 Black Left watches over her newest chick.

Our famous flamingo pair has done it again! The San Diego Zoo’s flamingo breeding season kicked off on April 24 when the first egg was laid by none other than my favorite girl and oldest female, 30 Black Left (see post Our Oldest Female Flamingo). She and her mate, 26 White Right, did the usual fantastic job that they do with incubating duties, sitting tightly on their precious egg. Like clockwork, 28 days later, the first flamingo chick of 2012 hatched on Tuesday, May 22. The incubation period for flamingo eggs is between 27 to 31 days.

When I went out to the exhibit at 6:30 that morning, I saw that the egg had pipped. A small hole had started the hatching process, and I could see the little beak diligently working on breaking out. By 10:30 a.m., the chick had chiseled half way around the shell, and by 2 p.m. it was free! Mom and Dad have been brooding the chick very tightly, keeping it nice and warm. By Wednesday morning, the chick was vocalizing, begging to be fed (Mom happily obliged); in the afternoon it was already trying to stand.

It never ceases to amaze me how incredible these birds really are, and after six years as their keeper, it never gets old. I am just as excited with each and every hatch as I was the first time I ever saw one. It warms my heart that our sweet old girl continues to be such a great mother and wonderful example to the rest of the flock. She will be 53 on June 23. Just as much credit goes to her mate, at only 20 years of age this year. He may be 33 years younger, but he is a great flamingo dad, and I truly believe that their bond is what is keeping her going strong!

I’ll be checking on the chick tomorrow morning (Saturday, May 26) to make sure all is well. I anticipate that sometime next week the chick will be off of its nest mound and starting to explore. They grow quickly, so you definitely want to see the sweet little ones before they get big.

I can’t forget about the rest of the flock: our second chick of 2012 hatched yesterday (Thursday, May 24). We hope to hatch more chicks this season, with about half of those being hatched and hand-reared at our Avian Propagation Center. These hand-reared birds will be joining the flamingos that are currently part of our Backstage Pass experience. If you haven’t had the opportunity to feed the sweet flamingos there, it is a life experience that can’t be missed! Even though I get to work with flamingos every day, I still had to partake in the fun and share with family members. They loved it, and so will you!

Athena Wilson is a senior keeper at the San Diego Zoo. Read her previous post, Screamer Family Returns.

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Screamer Family Returns

On Tuesday, July 12, we returned the crested screamer family to its home in the San Diego Zoo’s Flamingo Lagoon.  The family has been in an off-exhibit area, enclosed as a means to protect the chicks and provide them with the best opportunity for survival.  The chicks are two months old now, and we feel they have reached a good age and size for success in their mixed-species home.  Of the three chicks, one of them is a male and the other two are females.  One of the two females is noticeably smaller than her brother and sister, but all three seem to be in good health, and we will be keeping a close eye on the family!

Upon their release, Mom and Dad immediately began claiming their territory again. They displaced two of our male scarlet ibis and chased the female scarlet ibis around a bit as well.  There were also a few short sprints toward the flamingo flock, compliments of daddy screamer.  These behaviors were anticipated, and no one was hurt.  The screamer family has been settling in well over the past couple of days and even enjoyed a nice swim across the pool together yesterday afternoon.  We are happy to have them back for your viewing pleasure and hope that you enjoy them as well!

On a side note, for those who have been following the story of 30 Black Left, our oldest female flamingo, her chick hatched last Friday, July 8, and is doing very well! We don’t know the gender yet, but the chick is strong and in good health. It is still on the island with Mom and Dad (26 White Right) but should be exploring the rest of the exhibit soon. Come by and see flamingo chick #11 of the season and our crested screamer family!

Athena Wilson is a senior keeper at the San Diego Zoo. Read her previous post, Our Oldest Flamingo Female.

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Our Oldest Flamingo Female

30 Black Left.

In my last post (Happy Birthday, Flamingos!), I mentioned that our oldest female Caribbean flamingo, 30 Black Left, has a unique story. (Remember, we refer to the flamingos by their ID band’s number, color, and placement on the leg.) She hatched right here at the San Diego Zoo on June 23, 1959, making her 52 years old. Her reproductive history is a little unclear prior to 2005, but I can tell you something that makes her extra special, besides being the oldest female—almost every year she lays the first egg of the season!  The exceptions are in 2007, when she laid the third egg of the season (but it was the first to hatch a chick that year!), and in 2008, and I’ll tell you why in just a bit.

 

Since 2005, she has parented six chicks with the same male (26 White Right). This male is only 19 years old; he hatched at SeaWorld San Diego on June 1, 1992, and came to us in 1994. As with the oldest male in our flock (4 Green Right), they have one offspring who was hand raised and is currently residing in the Zoo’s Urban Jungle. If you participate in our Backstage Pass adventure and get to hand feed the flamingos, look for 246 White Right; he is their son, hatched in 2009. 30 Black Left and her mate are also internationally represented, having both their chicks from 2006 and 2007 shipped to the Emperor Valley Zoo in Trinidad in early March. Currently, they are incubating their second egg of the season. 30 Black Left laid the first egg of the season again this year, but it was not viable. The egg they are incubating now is due to hatch between July 7 and July 11. Fingers crossed that this one will hatch!

Now, why she wasn’t with 26 White Right in 2008? Early February of that year, the entire flock was moved to the Zoo’s Jennings Center for Zoological Medicine while we had some exhibit maintenance done. During that hospital stay, 26 White Right sustained an injury to his trachea that would require surgery, a tracheal resection. Having a world-class veterinary staff, we were not worried. However, this meant that he would have to stay at the hospital and recover while the rest of the flock returned to their newly renovated exhibit.

30 Black Left holds her own with the kids!

With breeding season quickly approaching, I became nervous that he would not be back in time for the pair to have their “first egg of the season!” All the while, a young male not even three years old started showing interest in 30 Black Left. Surprisingly, she did not refuse his advances. Then again, how could she have realized that her beloved mate would return? As far as she knew, he was gone.  And even though flamingos are usually monogamous, if something happens to their mate, they will quickly form a new bond so as to not miss a breeding opportunity. I was saddened by what was happening, but had not lost hope. 26 White Right returned to the exhibit on April 1, 2008—just 12 days after his surgery! After his release, I was sure that 30 Black Left would break the bond with the young male and return to her old mate. But wait—she didn’t even seem to recognize him!

Was his vocalization different due to the surgery and that was why she didn’t seem to know who he was? She ended up laying the second egg of the season soon thereafter; it was infertile, likely the result of the male being so young. Flamingos typically reach reproductive maturity between three and five years of age, and it usually takes a few tries before they are successful. Without any other choice, and in order to not miss a breeding opportunity, 26 White Right bonded with a new female. They had an egg together, but it did not hatch. It seemed that the bond between 30 Black Left and 26 White Right was broken forever, and this broke my heart—a pair I had seen so tightly bonded since I started working with the flock in 2006 was no more.

When the breeding season ended in 2008, since neither newly bonded pair had hatched an egg, they were free to roam about the exhibit since they did not have chick-rearing responsibilities. I started noticing that 30 Black Left and 26 White Right were spending time together again. With each day that passed, their bond seemed to get stronger until they appeared to be back to their old behaviors; they were almost never apart. During the breeding season of 2009, they were definitely back together again, and she laid the first egg of the season. I was so thrilled! How amazing is nature? And how awesome to have witnessed the strength of a bond between two very special birds?! They’ve been inseparable ever since.

Athena Wilson is a senior keeper at the San Diego Zoo.

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Happy Birthday, Flamingos!

This male is the oldest flamingo at the San Diego Zoo.

Today, June 23, is a very important day for the San Diego Zoo’s flamingo flock: it’s the birthday of the two oldest flamingos, which are exactly one year apart! In the wild, flamingos typically live to be between 20 and 30 years old. Remove predation, habitat destruction, and food scarcity and give them world-class veterinary care, and you can add at least 20 years to their lives! The oldest male flamingo hatched out right here at the San Diego Zoo on June 23, 1958, making him 53 years old. Exactly one year later, June 23, 1959, our oldest female hatched. Since then, they have both enjoyed extraordinary lives.

To tell individual birds apart, we put bands on their legs that may have a combination of letters, numbers, and colors. When possible, we try to band the males on the right leg and the females on the left leg. This is not always the case, depending on circumstances, but applies to the majority of avian individuals in the Zoo’s collection. I would like you to be able to pick out the birthday boy and girl on your next visit, but this is challenging when you’re searching a flock currently numbering 96 birds! But if you’re patient, you will be rewarded.

First, let me introduce you to our long-lived male. He has a green-colored band on his right leg with the number 4 on it. There are very few birds in the flock that have green bands anymore, so he won’t be too hard to find. We’ll call him “4 Green Right.” Males are also usually taller than females, so keeping that in mind will aid your search. His mate has a white-colored band on her left leg with a number 46 on it. If you see her first, he will likely be close by, unless they have an egg, in which case one of them will be incubating. They have had one egg together already this breeding season, but it was pulled due to infertility to give them another opportunity to lay a fertile egg. His mate is almost 13 years old and they have been together since 2009.

This pair has had two chicks together: one in 2009 that was hand-raised and can be hand-fed by you! He lives in the Zoo’s Urban Jungle and is part of our Backstage Pass experience. Look for his white band on the right leg with the number 243. The chick our pair had in 2010 is also a male and is on exhibit with the rest of the flock. When I looked back into our records, I discovered that 4 Green Right has parented at least 9 chicks since 1996. As a result of this, he is also a grandfather to 16 members of our flock. Not only is he currently well represented in our main exhibit and in the Urban Jungle, his female offspring from 2006 was recently sent to the Emperor Valley Zoo in Trinidad. His genes are being represented internationally as well!

Happy birthday, 30 Black Left!

Our long-lived female is one of my absolute favorite birds I’ve ever worked with (even though I try not to have favorites).  She has a beautiful and unique story that I don’t have time to go into today. Please check back for my next blog post, which will be just about her—she deserves it!

In the meantime, if you come to visit the birthday boy and girl before the next blog is posted, she is banded with a black band on her left leg with a number 30 on it (30 Black Left).  She is also currently incubating her second egg of the season with her mate, who is banded white, right leg, number 26. Look for either of them on the northwest end of the island where their current nest is located. Or if you see me in the exhibit feeding, she is usually standing close by.

Athena Wilson is a senior keeper at the San Diego Zoo. Read her previous post, Flamingo Egg-stravaganza. http://blogs.sandiegozoo.org/2011/06/20/flamingo-egg-stravaganza/

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Flamingo Egg-stravaganza

The San Diego Zoo’s Flamingo Lagoon is home to 86 adult Caribbean flamingos, several species of waterfowl, and many free-loading mallards. In the middle of the exhibit is a very “active” island, as it is breeding season for our beloved flamingos. On that island are several mounds—the flamingos’ nests. These mounds are started every April by the keepers to help us track which bird is on which mound and when exactly eggs are laid so we can anticipate when they will hatch.

We build small starter nest mounds in rows and draw a map of the island, further aiding in record keeping. Bonded pairs compete for the mound they want, occupy it, build it up, and lay their egg. The mounds can reach a height of 2 feet (0 .6 meters)! The clutch size for flamingos is a single egg, and both parents share incubation duties. The egg hatches 27 to 31 days later.

From the time the egg is pipped, it can take up to 36 hours for the chick to hatch completely, resulting in one of the cutest and softest chicks I’ve had the pleasure of working with. They are covered with white to light gray down, with swollen pink legs and a straight pink bill. After about a week, those swollen legs turn a charcoal gray, and their bill starts to curve downward. When their feathers start to come in, they are a brownish gray color. They slowly turn pale pink and won’t reach their mature bright coloration for two to three years. Their legs take about the same amount of time to turn back to pink. Another transformation they undergo is their eye color: young flamingos have dark eyes that turn to a pale yellow as they mature.

We usually process each chick when it is three to five days old; this involves weighing it, giving it a microchip ID, and performing a quick visual exam before being returned to its eagerly awaiting parents. I find these days rewarding, as I get to hold the chicks and, as I mentioned, they are one of the softest chicks I’ve ever felt!

A total of 27 eggs have been laid so far this season. Some of these were pulled due to infertility, some were left unattended and therefore removed, and a few were broken by pairs trying to take over occupied mounds. As of today we have 10 chicks. The first chick hatched out on May 27, and the youngest chick hatched on June 11. Both Mom and Dad take turns brooding their chick (keeping it warm). They also share feeding responsibilities. Flamingo chicks are fed crop milk, which is very rich in fat and protein and is a blood red color. The chicks’ vocalizations stimulate the production of crop milk. If you listen closely, you’ll hear a distinct difference in their vocalization when they are standing under their parents, begging to be fed. It is a higher pitch and more rapid than their usual calls.

As the chicks get older, feedings may last several minutes. Some feedings last so long that I have gotten calls on the radio about concerns from guests that the birds’ beaks are stuck together. Fortunately, this is never the case. Sometimes the parents are sloppy feeders and spill some of the crop milk on their chicks; this makes it look like the chick is injured, but again, this is not the case. What’s interesting is that as the parents feed their chicks this crop milk, they are drained of their color—so much so that their plumage turns a pale pink or white! The parents gain this color back eventually as the chicks become independent and eat on their own. It may takes months, though, because some of our chicks like to be fed until they are 10 months old, even though they are perfectly capable of eating on their own.

We are hoping to hatch out two more chicks this year to make it a full dozen! Fingers crossed, but in the meantime the 10 chicks present are growing fast! Come by and see them as soon as you can. They are my reward for working hard all year, and I hope you all enjoy them as much as I do!

Athena Wilson is a senior keeper at the San Diego Zoo. Read her previous post, Crested Screamer Family Update.

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Crested Screamer Family Update

The screamer family relaxes in an off-exhibit area.

For those of you who have been eagerly searching for our crested screamer family in the San Diego Zoo’s Flamingo Lagoon, I appreciate your patience. I wanted to make sure that our screamer family was doing well before updating everyone and hoped to have good news to report. And good news I have. The screamers’ second clutch consisted of only three eggs; amazingly, all three hatched! The first two chicks hatched on May 12, and the third chick hatched on May 13.

Three healthy, and hungry, screamer chicks!

Based on our unfortunate loss of the previous three chicks (see post Welcome to the World, Screamers), we had planned to move the family to our bird holding area where they could be protected from any potential dangers. The entire family was moved on May 14. The move went very well, thanks to my amazing coworkers in the Bird Department. Both screamer parents have been doing a great job caring for their chicks, as they have little to no disturbances to worry about in their current holding pen. They don’t have to worry about flamingos marching by their nest, ducks stealing their food, and, most importantly, native birds that are potential predators. The chicks are a month old now, and even though that may seem to be a decent age for a chick, they are extremely slow growers!

I don’t have an exact date as to when the family will be returning to its exhibit, as we want to make absolute sure that we have given them the best chance for success. I CAN say that it will be worth the wait, and it should be sometime soon. It will be the first time that the Flamingo Lagoon will be home to a family of 5 crested screamers, and with at least 10 flamingo kids running around as well, I’m sure there will be plenty of entertainment. I hope everyone will get along and the youngsters take after their father. Many of you are already aware that their mother is very aggressive and can make my job quite challenging☺.

Athena Wilson is a senior keeper at the San Diego Zoo. Read her previous post, Sociable Weavers: Amazing Architects.

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Sociable Weavers: Amazing Architects

One of the most intriguing species of bird that I have the pleasure of working with is also one of the most overlooked: the sociable weaver. Their exhibit is located in the San Diego Zoo’s Lost Forest, across from the gibbons. It’s easy to pass right by them, since at first glance their appearance is not that impressive. They look very similar to the common house sparrow, so what could be that interesting about them? Please allow me to enlighten you.

Athena checks the sociable weaver nest.

Despite their small size, they are capable of completing an extremely large task. They create the largest communal nest of any bird in the world! These nests are often referred to as “apartment complexes,” as they are used for both roosting and breeding. A single colony nest can weigh up to a ton and may house over a hundred birds. There are several chambers in the nest, and the colony may use it for many generations.

In the interest of being efficient, these birds are constantly communicating with each other and constantly building! You can hear all the chatter as you approach their exhibit. You’ll also notice a large pile of nesting material on the ground that they can pull from throughout the day. As their keeper, it is my job to keep the material coming, and it has been a challenge to provide the proper items.

In the wild they would have access to a variety of plants, and each item they add to the nest serves a different purpose. Sociable weavers prefer rigid material for the roof, chambers are made stable with various dried grasses, access to these chambers are usually surrounded by straw, and the chambers are lined with soft materials (grasses, feathers, cotton, etc.) for comfort. Over the years they have been offered feathers, silk floss, camel hair, small sticks, pine needles, Bermuda hay, and dried grasses. I have worked with this colony for 4½ years now, and I have learned that their favorite items are pine needles, Bermuda hay, and dried Pennisetum grasses. And they certainly keep me busy with the challenge of providing them with plenty of material every day!

Recently the nest was the largest that it has ever been. Due to its ever-increasing size, as well as the weather, portions of the nest have started to fall. This is a natural process, and the birds have already begun investigating other potential nesting locations. They may also choose to repair the areas where chunks of the nest have been lost. Whatever the outcome may be, the colony benefits as they have the opportunity to renew their nest and start with fresh material. A healthy nest helps to maintain a healthy colony of birds.

The next time you’re walking along Monkey Trail in Lost Forest, take a moment to watch these active birds. I’m sure you’ll be impressed by their nest-building skills. And since the San Diego Zoo is home to the only sociable weaver colony in the United States, you won’t want to miss the opportunity to see them up close!

Athena Wilson is a senior keeper at the San Diego Zoo. Read her previous post, Welcome to the World, Screamers!

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Welcome to the World, Screamers!

On Monday, February 7, we welcomed three crested Screamer chicks to our San Diego Zoo family (see post, Something to Scream About). I had been eagerly checking the nest every day to see if the eggs had pipped yet. When I checked at 9 a.m., the eggs were still completely intact, but less than two hours later, they decided it was time to come out. The female screamer assisted with the hatching process, turning the eggs so that the chicks could come out more easily. By 4 p.m., all three had hatched! This was quite a surprise to us all, as it was a very quick pip-to-hatch time period. Some bird species take anywhere from 24 to 48 hours to hatch; I guess these kids were ready to see their new world. They remained on the nest with Mom and Dad taking turns brooding them for the first couple of days. On Thursday, February 10, the chicks came off the nest for the first time.

Screamer chicks are precocial, which means that upon hatching their eyes are open, they are covered with down, and they are mobile. They are able to pick up food on their own, although they may need some assistance from their parents in finding food. A precocial chick is developmentally more mature than an altricial chick, which usually hatches with eyes closed, are relatively immobile, and are also completely dependent on the adults.

So far, so good. All three chicks have been observed eating and drinking. We provide them with a mixture of nutritionally balanced waterfowl pellets that are ground up to allow for easier consumption, finely chopped romaine lettuce and fruit, as well as mealworms and young crickets. Adult screamers are herbivores, but chicks require a diet higher in protein during development, which is why we provide them with insects. Mom and Dad will care for the chicks, keeping them close by and brooding them when they are cold for 8 to 10 weeks. They will be fully independent between 12 and 14 weeks of age, although it is not unlikely that the chicks will stay close to the parents as long as their presence is tolerated.

The first several days and even weeks of a chick’s life are nerve-racking for a bird keeper. We must keep a very close eye on them and watch for any behavioral, developmental, or health abnormalities. I am thrilled that all three chicks hatched and am feeling optimistic, as this is the second parental opportunity for the female, and our male is a seasoned pro.

Stop by our Caribbean flamingo lagoon at the front plaza to see our beautiful crested screamer family. The chicks will be right next to Mom and Dad or under foot. You may even be lucky enough to see them taking a swim, which is always entertaining. Even though they’re precocial, they can still be a bit clumsy at times.

Athena Wilson is a senior keeper at the San Diego Zoo.

Update: February 21, 2011
Unfortunately, we lost all three screamer chicks. We lost one of them of unknown causes, the second one due to predation by a wild great egret. The third one went to the veterinary hospital; despite the efforts of the veterinary staff, this chick passed away a day later of unknown causes. A necropsy will be done on each one of them to determine the cause of death. I hope we will learn from them to see if there is something we can do in the future.

The good news is that we will be allowing them to breed again this year (it’s not too late). If we get chicks again, we will most likely move them to a safe place off exhibit and bring them back as a family when the chicks are big enough to not be at risk for predation. I apologize for the sad news. It was a rough few days for me as their keeper :(
~Athena

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Something to Scream About

A sharp, keratinous spur on each wing helps screamers protect themselves by wing slapping and striking with these spurs. Click on images to enlarge.

What are those large, gray birds in the San Diego Zoo‘s Caribbean flamingo exhibit?  They look like turkeys or “raptors on stilts,” as I like to call them.  Interestingly, they are classified into the same scientific order as waterfowl (ducks) but are in their own unique family. There are three different species of screamers, all of which reside in South America.  We are home to a pair of crested screamers Chauna torquata, also known as southern screamers.  They can be heard from far away, and if you are lucky enough to hear them vocalize, you will quickly learn how they got their name. Screamers are excellent swimmers, even though they barely have any webbing on their feet. They can also be very aggressive, and if you have ever seen me in the exhibit speaking loudly at them, telling them to “back-up,” it is not because I am trying to be mean; my intention is to establish my dominance.

Our screamer pair is unique because they have a very romantic story (in my opinion, at least).  First, let me give you a little history about our male. He is approximately 30 years old now! He came to us when he was about a year old in February 1982. He was paired up with a female and together they parented a total of 24 chicks over a span of 8 years from 1988 to 1996. Sadly, his original mate passed away in 1997. In the wild, these birds would live to be anywhere from 10 to 15 years old but can live to be up to 35 years old in zoos.

Will our screamers become parents again?

The male was by himself until one beautiful day in 2008, when we received a young female from the Louisville Zoo. She was a sight to see!  Barely over a year old when she arrived, she still had some reminiscent juvenile plumage but nevertheless was larger and more robust than the male. They were introduced in adjacent pens up at the Zoo’s hospital, and it was love at first sight. They would often be seen standing near each other (still separated by fencing), bill-clapping  to each other, which in screamer language can be interpreted as “I like you.”  This behavior can also be observed on exhibit, and following the bill clapping you can see them preening each other.

As soon as it was apparent that they would get along if put in the same enclosure, they were brought to the Caribbean flamingo lagoon on the Zoo’s front plaza and have been inseparable ever since. The female was not yet reproductively mature, so we did not anticipate breeding for quite some time.  Early last year was the first time we observed copulation; in the bird world, that is the term we use for breeding.  Much excitement followed as the female laid her first egg!  But with the male being at the age he was, we wondered if the eggs could even be fertile.  Their first clutch consisted of two eggs that were laid seven days apart.  Typically, a clutch contains two to six eggs, with an egg being laid every two days.  Both eggs proved to be infertile, so they were pulled from the nest to allow the pair to try again. Shortly after, the female laid five eggs perfectly, each one laid two days after the previous egg.  How exciting! Two of the five eggs hatched, and the female behaved like a seasoned parent with her experienced mate showing her the ropes. They successfully parent-reared one of the two chicks (the other passed away at only two weeks of age due to health complications), and that male will be transferred to another institution soon!

Currently you can observe the crested screamer pair on their nest for their second breeding season together. Six eggs were laid, but only three remain, as the other three were candled and proven infertile or not viable.  The remaining three eggs are due anytime now up until February 14! The pair can be easily viewed from the bridge of the flamingo exhibit, where one of them will be sitting tightly atop a clump of Liriopes at the water’s edge.  If you get the chance to stop by, we hope that all three eggs will hatch, and we can enjoy seeing some of the cutest chicks in the bird world.  A screamer chick looks like a miniature Big Bird from “Sesame Street” with bright yellow down and thick, swollen orange legs. What a perfect Valentine’s Day gift for their keepers and the Bird Department!

Athena Wilson is a senior keeper at the San Diego Zoo.