Happy Birthday Willie!!!

The Houston Zoo is wishing chimpanzee Willie a very Happy Birthday! Over the past five years, since the opening of the chimpanzee exhibit in 2010, we have watched as Willie has grown from a playful juvenile chimpanzee to a mature adult chimpanzee. During this past year, he has risen in rank to become the dominant male in the group.

10 - year old Willie the Boss
10 – year old Willie the ‘Boss’

When Willie first came to the Houston Zoo, he was the smallest member of the group and at six years old still spent the majority of his time with Lulu and Lucy, the mothers of the group. He continued to rely on them for protection during group conflicts and his primary goal in life and in interactions with the group was to just have fun and play. He played an important part in getting the original chimpanzee group comfortable living together in their new home as his solution to any tension or nervousness was to encourage everyone to play!

Willie (2)
6 – year old Willie the ‘Kid’

In the wild, chimpanzees spend the first seven years of their lives with their mothers. These juvenile chimpanzees are characterized by tan faces and a white tuft of hair above their rear ends. Between the ages of 6-9, adolescent chimpanzees will start interacting more socially with other members of the group. They lose their white tuft of hair and their faces start to change from a light tan color to black. During this time, males will spend less and less time with their family and more time interacting with adult males in the group. It is during this time that young males start participating in boundary patrols and begin to try to figure out their place in the male hierarchy. These young ‘teenage’ chimpanzees often find themselves involved more in conflicts as they try pushing boundaries and establishing themselves in the hierarchy.

At eight years old, Willie started spending less time with Lucy and Lulu and more time with Mac, the dominant male at the time. Keepers called him “Mac’s Shadow” as he would never be very far from Mac’s side. He always seemed to be looking to Mac for guidance on how to behave. During this time, Willie also started challenging the females and lower ranking males. Anytime a conflict occurred, you could find Willie right in the middle of it. His favorite tactic was to throw dirt and then run away before anyone could catch him. The only chimpanzee that could discipline ‘teenage’ Willie successfully was Mac. Willie gained rank quickly.

Willie 1
8 – year old Willie the ‘Teenager’

Over the last two years, the original chimpanzee group has been integrated with a new chimpanzee group of six chimpanzees. Willie initially was very friendly but shy about meeting his new friends. His initial interactions with the new chimpanzees were submissive and friendly. Due to his friendly initial interactions and his playful nature, Willie quickly made friends with the new chimpanzees. As the groups were combined and Willie became more confident in the new group, keepers started noticing him intervening in conflicts instead of causing them. Keepers also noticed that many of the chimpanzees started to look to Willie for reassurance and support during conflicts. One of a dominant male chimpanzee’s main roles is to manage conflict within the group. Willie seemed to be fulfilling this role in the new group.

Willie can often be found at the center of grooming and play sessions within the newly combined chimpanzee group. Besides being strong enough to maintain order, another important trait for a high ranking chimpanzee is the ability to gain and maintain allies. Bullies usually don’t last long as dominant males as the other chimpanzees in a group often band together and overthrow them. Willie’s friendly nature has gained him lots of allies. Even though he is now in charge, his favorite strategy to maintaining order is to encourage everyone to play. The one thing that has not changed about Willie in the past five years is that his primary goal in life is to just have fun and play!
Chimpanzees in zoos can live into their sixties. We look forward to celebrating many more birthdays with Willie and watching him as he continues to learn and grow into an impressive adult male chimpanzee!

Zoe the Zookeeper's Adventure

This post is written by Houston Zoo Aquarist Amy Trang.

If you have ever visited Kipp Aquarium here at the Houston Zoo, you may know we have a sea turtle in one of our main exhibits. But what you might not know is these sea turtles are being rehabilitated and will be released back into the ocean when they are healthy! I am here to tell you the process of how this happens…

Sea turtle
Green sea turtle at the Kipp Aquarium.


The NOAA (National Oceanic and Atmospheric Administration) facility in Galveston responds any time there is a report of a stranded or injured sea turtle. A few reasons a sea turtle might get stranded is an injury from a hook or fishing line, missing flippers, caught in sargassum that has washed ashore, or stressed due to the cold in winter months. NOAA staff will bring any turtle needing medical attention to our veterinary clinic. If space is available in Kipp Aquarium, we are given a turtle to rehab while on exhibit for the public to learn about these awesome creatures!

Our main goal when rehabilitating a sea turtle is to make sure it is eating and growing. Most turtles we care for just need a safe place to gain some weight, giving them a much higher chance of survival. In the wild, a green sea turtle is primarily herbivorous as an adult, therefore each day the sea turtle eats lettuce in the morning, which we spread throughout the exhibit so the turtle can forage for itself. Most of the weight gain will come from the turtle receiving some sort of protein (shrimp, capelin fish, and squid) in the afternoon. The turtles receive monthly weights and measurements to ensure it is growing. To give you an idea, the green sea turtle we rehabilitated from June 2013 to May 2014 came in weighing about 6 pounds and when released weighed over 25 pounds! We usually have them for about a year before they get released. When our veterinarian and NOAA staff agrees that they are at an optimum size and the temperature of the Gulf of Mexico is warm enough (usually May or June), we will prep the animal for release. The sea turtle will have its measurements taken one last time and will be given pit tags. Pit tags are a means of identification for an individual sea turtle.

Pit Tag being placed in a sea turtle before release.
Pit Tag being placed in a sea turtle before release.

If a turtle becomes stranded, a handheld scanning device can be placed over the area where a tag was inserted and will read a code that can identify this turtle. If no code appears, this turtle has not been stranded before. Pit tags don’t track the turtle, but allows NOAA to know if they have seen the turtle if it becomes stranded again.
One last crucial aspect of the release is the location. The release location depends on the species of sea turtle and what its primary diet is. A green sea turtle would be released on the bay side of Galveston Island because this is where seagrass, a green’s main food source, is plentiful. We would release a kemp’s ridley sea turtle on the ocean side of the island, however, because its primary diet is crabs and that is where crabs are more common. Then we drive out to the island, let them go and say good luck!

Sea turtle being released by Houston Zoo staff.
Sea turtle being released by Houston Zoo staff.

We love successfully rehabbing sea turtles each year and returning them to the wild. We hope you enjoy learning about these amazing animals!
If you ever seen a stranded or injured sea turtle, please call 1-866-TURTLE-5 to report it!

Be sure to stop by “Zoe the Zookeeper’s Adventures” on Fridays October 10, 17, 24 from 9am-1pm and on Saturdays and Sundays October 11 & 12, 18 & 19, 25 &26 from 9am-4pm to learn more about these efforts and to participate in some fun activities.

Zoe the Zookeeper's Adventure

Houston Zoo keepers are very passionate about conservation efforts concerning a variety of animals! One of the awesome aspects of working at the zoo is the opportunity to assist with rehabilitation and release efforts for some of these animal species.

During the month of October, guests can learn about four of the rehabilitation and release programs that Houston Zoo staff have had had the opportunity to work with by participating in “Zoe the Zookeeper’s Adventures”. Each Friday, we will also highlight one of these programs in this blog.
The first amazing animal we are featuring is the Howler Monkey!Howler Monkey Female-0001

There are several species of howler monkeys that can be found in forests throughout Central and South America. One of the most distinctive features of the howler monkey is their territorial call, which is where the name “howler” monkey comes from. This call can be heard from over 2 miles away. They actually have an enlarged hyoid bone which is what enables them to produce this call.

Another cool feature of the howler monkey is that they have a prehensile tail. This basically means that they can use their tail like a third hand! This is really helpful for the howler monkey since they rarely come down to the forest floor and spend all their time in the trees. Being able to hold on to branches with their tail allows them to use their hands for other important tasks like picking leaves and fruit to eat.

Howler monkeys, like other primates, do not make good pets. Having a howler monkey as a pet can be harmful for both the people and the monkeys involved. Houston Zoo primate keepers have traveled to Belize the last three years to assist ‘Wildtracks’ in its program to rehabilitate confiscated ex-pet howler monkeys. Once they have been integrated into a group and mastered the skills needed to thrive in the wild, they are then released and monitored in an area of protected forest.


Be sure to stop by “Zoe the Zookeeper’s Adventures” on Fridays October 10, 17, 24 from 9am-1pm and on Saturdays and Sundays October 11 & 12, 18 & 19, 25 &26 from 9am-4pm to learn more about these efforts and to participate in some fun activities.

Chimpanzee Introductions: Where to Begin?

Chimpanzee Introductions:  Where to Begin?

As our newest group of six chimpanzees has become very comfortable in their new home, we have begun the slow process of combining them with our original group of ten into one large community.

Chimpanzees are very social and live in large fission-fusion communities, meaning that they come together at certain times, but may not see every individual of their community every day. The regular interactions that occur between members of the group are a very important part of their lives and provide both mental and physical stimulation. The bonds that are formed from these interactions are crucial in developing alliances and play a large part in the make-up of the group hierarchy.

In the wild, young females that are leaving their birth community would first encounter males from the new group. Due to this, our first step in integrating the two groups has been introducing the young females from the new group to the males in the original group. Since alliances play such a large part in group dynamics, most of the introductions are done with a chimpanzee from one group meeting a chimpanzee from another though often a shy chimpanzees will be introduced with a friendly buddy from their own group.

In addition to natural history, keepers have been observing the interactions between the two groups for the past few months as the chimpanzees have been able to see and hear each other though not touch. These observations, along with knowledge of each chimpanzee’s personality, have helped keepers plan introductions so that they are a positive experience and so that bonds can start to form between different members of the two groups.

Positive interactions have occurred between several members of both groups but two specific chimpanzees have been instrumental in making members of both their own group as well as new friends feel comfortable with introductions.

In the original group or Mac’s group:

Abe, a calm and friendly older male, was an instant hit with the females of Toby’s group. He and Kira kissed on first meeting. He won Tanzee’s heart by letting her steal broccoli right from his hands. His laid back personality and willingness to do whatever the females choose, whether it be sitting still for hours so they can groom him or playing a rowdy game of chase, has made him a favorite.

Abe grooming Sierra, the dominant female in the new group.
Abe grooming Sierra, the dominant female in the new group.


In the new group or Toby’s group:

Kira, the youngest and a very playful female, has instantly greeted every new friend with a hug. She is always willing to play a friendly game of chase or tug of war with a blanket. Since the males in Mac’s group have always loved to play, her enthusiastic greeting and friendliness has been very well received.

Kira and Willie: the ten year olds.
Kira and Willie: the ten year olds.


The next steps will depend on what the chimps are telling us.  There is no guarantee all individuals will get along with all other individuals, and that’s OK.  We are fortunate enough to have a large and very flexible housing area and can manage multiple groups as necessary.  Stay tuned, we will update you further as we progress!

‘Spotlight on Species’ Chimpanzee

Chimpanzees are very intelligent and incredibly resourceful when in comes to creating ways to obtain their food.  Visitors to the Houston Zoo can see an example of this creativity on a daily basis during the 12:30 keeper chat. The chimpanzee exhibit has its very own termite mound replica and guests can watch the chimpanzees modify and use branches to retrieve delicious treats such as yogurt, bananas, or juice .

Lucy fishing at replica termite mound.

Chimpanzees in the wild exhibit a similar behavior by modifying branches to fish for termites. Other examples of tool use by chimpanzees in the wild include modifying branches into spears for hunting small mammals, using rocks to crack nuts, wadding leaves as sponges to soak up water, and bunching leaves and branches to make comfortable nests to sleep in at night.

When visiting the Houston Zoo chimpanzee exhibit, take a second to watch the different techniques the chimpanzees use to ‘fish’ for their treats in the termite mound.  Lucy’s favorite spot is the top of the termite mound. This is prime real estate when it is time to ‘fish.’ It is also a great spot for her to observe guests of the zoo and all their entertaining antics. She usually chews on the end of her branch in order to make it better able to soak up liquids or makes it flatter so that it can scoop more treats out of the tubes.



Willie, the juvenile, has his own unique technique. Instead of modifying his own branch, he usually tries to steal someone else’s already modified tool. If he doesn’t steal the tool, he may sit just next to another chimpanzee and take their delicious treat off the end of their branch before they get a chance to enjoy it.




Let us know your suggestions for what tasty treat to put in the chimpanzees’ termite mound, then stop by on May 25-27 for a ‘Spotlight on Species’ focusing on Chimpanzees to see what they are fishing for that day. The ‘Spotlight on Species’ will be from 10am-3pm and there will be many fun and educational activities to help visitors learn about chimpanzees. You can bring in old cell phones for recycling in exchange for a chimpanzee conservation bracelet. Meet the primate keepers who care for the Houston Zoo’s chimpanzees at 12:30 and 2:30 during a keeper chat.

The Houston Zoo is Leaping for Lemurs & We Want You to Join In!!!!!!!

Did you know that Coquerel’s sifaka can leap over 20 feet from tree to tree?


Gaius: Male Coquerel’s Sifaka


These amazing animals are endangered and found only in the northwestern forests of Madagascar. They have strong legs that not only help them make these incredible long leaps but also assist in their typical locomotion style called vertical clinging and leaping. It is called this because they maintain an upright posture when moving. On the ground, they move in a distinct sideways hop. High up in the trees, they leap from branch to branch or tree trunk to tree trunk, swivel in mid-air,  and then cling to whatever they land on.


Zenobia: Female Coquerel’s Sifaka

Interested in learning more about these leaping lemurs? Join the primate zookeepers on September 1, 2 & 3 from 9am-3pm in the Wortham World of Primates at the Houston Zoo for a Spotlight on Species event highlighting the Coquerel’s Sifaka as well as many other Madagascar species. In addition to speaking with zookeepers, visitors will have a chance to take part in several fun ‘lemur’ activities as well as support lemur conservation through the purchase of unique item from Madagascar and Houston Zoo animal paintings. Then see how your leaping skills measure up by visiting Sky Zone Sports (www.houston.skyzonesports.com) indoor trampoline park for “Leaping for Lemurs” on September 5th & 6th. They will donate 25% of the proceeds on these two days to lemur conservation in Madagascar. So come out and leap into action to help save these rare and beautiful animals!

The Houston Zoo is Leaping for Lemurs and We Want You to Join In!!!!!!!

Lemurs are an amazing group of primates that are only found in Madagascar, an island off the east coast of Africa. There are a wide variety of lemur species with a great deal of diversity in appearance and behavior, from the tiny mouse lemur to the elusive nocturnal aye-aye. Different species consume a vast array of diets such as the bamboo lemurs that survive mainly on bamboo or the fruit-eating ruffed lemurs. Some lemurs, like the ring-tailed lemur, live in large troupes led by a dominant female, others, like the red-fronted lemur, have no noticeable hierarchy within their smaller groups. Despite all their differences, one thing that all lemurs have in common is that they are all affected by habitat loss, poaching and the pet trade, and need our help.


Travis, a crowned lemur, and
Beet, a red-fronted lemur. Photo by Tina Carpenter.


With so much diversity and with so many fascinating facts, we can’t help but love lemurs and that is why we are having almost a whole week dedicated to promoting lemur conservation!

It all starts on September 1st with a three day Spotlight on Species highlighting the Coquerel’s sifaka. This event will occur from 9am-3pm in the Wortham World of Primates at the Houston Zoo every day through September 3rd. Visitors to the zoo will be able to learn all about lemurs and other animals native to Madagascar from the zookeepers that care for these species here at the zoo. They will be able to see a wide variety of Madagascar species including our very own Coquerel’s sifaka pair, “Zenobia” and “Gaius”, as well as the newest addition to the primate department, a baby ring-tailed lemur! There will also be face-painting and fun ‘lemur’ activities for the whole family. While learning about lemurs, you can also support lemur conservation as zookeepers will be selling a wide variety of unique items from Madagascar as well as paintings completed by animals here at the zoo with the profits going to support conservation efforts in Madagascar.

Ring-tailed Lemur Family. Photo by Stephanie Adams.

On September 5th & 6th, show off your lemur leaping skills by visiting Sky Zone Sports indoor trampoline park (www.houston.skyzonesports.comfor “Leaping for Lemurs”. They will donate 25% of the proceeds on these two days to lemur conservation in Madagascar. So come out and leap into action to help save these amazing animals!

Problem Solving with Apes: An App for an Ape

How do we decide which apps to introduce to the chimpanzees and the orangutans?

When trying to develop new enrichment activities, a good starting point is to look at the natural history of the animal. What would they be doing in the wild? How do we encourage these natural behaviors with our enrichment activities?

Orangutans are semi-solitary, meaning they spend most of their time alone, though offspring stay with their mothers for 8-9 years. They also live high in the canopy of forests, which generally has dense foliage making it easier to stay out of sight.

Aurora & Cheyenne (Photo by Stephanie Adams)

On the other hand, chimpanzees live in large groups called communities. They are very social and spend a majority of their time interacting with other chimpanzees. Chimpanzees are very expressive having many vocalizations and facial expressions in order to communicate with each other. They also are known for their loud and impressive displays.

The major portion of the diet of both chimpanzees and orangutans consists of brightly colored fruit. Both species also use tools to help them obtain their food. Chimpanzees, particularly younger individuals, can become easily distracted when faced with a new challenging task. In contrast, orangutans can spend hours completely focused on the same task.

Now we have some background on orangutans and chimpanzees, but how does that help us pick out apps for them? And how is the iPad encouraging natural behaviors? Obviously, apes in the wild are not using iPads.

While apes in the wild may not be using iPads, a natural behavior for them is to observe their environment and investigate when something is different or unusual. The iPad can be used to continuously provide the apes with new apps to study. Another natural behavior for apes is problem-solving, which specific apps can be used to encourage.

We know that both chimpanzees and orangutans are curious as well as liking brightly colored objects as these often signal delicious food. So we want to look for apps that have lots of bright colors.  Since chimpanzees are easily distracted, they will probably do better with apps that have lots of movement to keep their attention. Orangutans may be interested in apps that have lots of movement but as they are more focused they may also use apps that are not so busy. We started out by looking at apps that were aimed at young children. These tend to be bright and aimed at keeping the user’s attention.

Indah, an orangutan, looking at pictures on the iPad

Apps include: Zoo Sounds and Various interactive storybooks

Both the orangutans and chimpanzees at the Houston Zoo already enjoy painting, so painting apps were a good option.

Apps include: Doodle Buddy, Paint Sparkles, and Finger Paint

Chimpanzees, especially males, who often produce noisy displays, may appreciate apps that are very noisy.

Apps include: Music Sparkles, Tap Drums, and Monsters

Orangutans are very goal-oriented so apps that involve completing a task may pique their interest.

Apps include: Cat Fishing, Tap Tap Ants and Match Animals

Since both species are naturally curious about the world around them, apps that include videos, pictures, and audio of nature as well as other animals were also introduced.

Apps include: Sound Touch Lite, Go to the Zoo, and Discover Uganda

The basic camera and video app for the iPad can be useful in capturing exciting behaviors and playing it back to them. Most of the apes become particularly excited when they are viewing themselves on the iPad.

Now that you have learned how we go about picking iPad apps to introduce to the Houston Zoo chimpanzees and orangutans, perhaps you can suggest a few apps that may capture their interest.




Learning how to use all this new technology is hard work!

Well, except if you are a chimpanzee or an orangutan at the Houston Zoo, then it can be tons of fun. As mentioned previously in Problem Solving with Apes, the orangutans and chimpanzees are using the iPad as a form of enrichment.

So how does a chimpanzee or orangutan use an iPad?

Kelly using iPad

For starters, the iPad is held by a keeper outside of the ape’s enclosure. Orangutans with their curious nature love to take things apart to see how they work. Rambunctious chimpanzees tend to use everything in their path when creating big noisy displays. Unfortunately, the iPad would not withstand either one of these situations. A protective case called an Otterbox is also used to ensure that the iPad is not damaged by the more enthusiastic apes.

Both the orangutans and chimpanzees are still able to touch and interact with the iPad. The choice to interact is completely up to the individual. They can walk away from the iPad when they choose and no food treats are given as a reward for interacting with the iPad. Playing with apps on the iPad is the treat! Most of our chimpanzees and orangutans love this new enrichment item and become very excited when they see the keeper approaching with it.

Mac playing the piano



To introduce the iPad, keepers started with just showing it to the apes. Videos were shown first as well as various storybooks. They are especially fond of videos featuring themselves or other apes! Keepers then began to demonstrate apps to them. As individuals showed interest in touching the screen and interacting with the iPad, keepers gave them the opportunity.

Cheyenne and Aurora fishing on the iPad






At this point, one of the most difficult challenges was discovered. The iPad reacts to an electrical current from the body. Touching with a fingernail does not work and as Cheyenne, an orangutan that is particularly good at problem solving, discovered neither did any of the amazing tools she created using branches, paper, or cardboard.





Some quickly figured out that the finger pad was the best option to use to work with the iPad. Others eventually caught on after observing the successful interactions of other apes. Lulu, an independent chimpanzee, invented her own way of interacting with the iPad using the back of her finger. This is particularly useful if you want to paint a large area of the iPad screen quickly. Lulu, who is one of the older mothers in the chimpanzee group, was also helpful in demonstrating how to use the iPad to other more hesitant chimpanzees.

Now that most of the chimpanzees and orangutans have figured out how to interact with the iPad, the next step is introducing them to a wide variety of apps. Stay posted for details on just how we pick out apps for them to use.


Problem Solving with Apes

Chimpanzees and orangutans, two great ape species, can be found at the Houston Zoo. These amazing animals are incredibly intelligent. In the wild, this intelligence is constantly being put to the test as they encounter novel situations on a daily basis. To deal with these novel situations as well as completing everyday tasks, apes have developed keen problem solving skills. They use tools such as branches or rocks to help them obtain difficult food items such as nuts or termites. They build complicated nests out of branches and leaves each night high up in the trees to help keep them safe as they sleep. They use leaves to shelter them from rain or to collect water to drink.

Indah painting on iPad

Great apes that live in zoos such as the orangutans and chimpanzees have a team of dedicated keepers that ensure that their basic necessities such as food, water, and safe shelter are met on a daily basis. However, a zoo keeper’s job also involves ensuring that the animal has the highest quality of life possible. So not only are keepers interested in meeting the animal’s basic needs but also in making sure that the animals are constantly being engaged and stimulated by their environment. This is an especially important challenge when working with great apes due to their intelligence. The devices and activities that keepers use to accomplish this goal are referred to as enrichment as they enrich the lives of the animals.

Apes can quickly figure out many enrichment devices and keepers constantly are faced with the problem of trying to come up with new ideas to capture their interest. The Houston Zoo primate department’s newest solution to this problem is ……. the iPad!

Sally creating a masterpiece with a musical app.


Now many of you may wonder, what do the orangutans and chimpanzees do with an iPad? The answer is … they play with apps, of course! The iPad screen is the perfect fit for orangutan and chimpanzee fingers. Its small size makes it very easy to move so keepers can introduce it to the chimpanzees in the training room, to the orangutans at the viewing window or at any of the many rooms found in the animals’ holding area. The quantity and variety of apps available make it easy to keep the device novel and interesting for both the orangutans and the chimpanzees. Stay posted for more updates on this new fun enrichment project with our orangutans and chimpanzees!



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