Mac the Chimpanzee Passes Away

It is with great sadness and a profound sense of loss that the Houston Zoo announces the passing of Mac, one of our beloved chimpanzees.


On Tuesday, May 13, Mac and 2 members of the Houston Zoo’s chimpanzee family were sedated for their regularly scheduled veterinary medical examinations. The sedation and the exams proceeded normally. However, when the Zoo’s veterinary team began to reverse Mac’s sedation, he did not immediately respond. The veterinary team immediately administered aggressive supportive therapy including oxygen support, antibiotics, and analgesics (pain medication). An analysis of an MRI scan by experts in human neurological medicine revealed that despite the supportive care provided following the sedation reversal, Mac’s neurological functions were compromised and irreversible. Mac was humanely euthanized.


Mac has lived at the chimpanzee habitat in the Houston Zoo’s African Forest since he arrived in July 2010 with 9 members of his extended chimpanzee family. Mac settled in to his new home, his family and his keepers saw him emerge as a leader of the troop. The Houston Zoo’s chimpanzee keepers will closely observe the family’s behavior over the coming days and weeks and provide supportive care for Mac’s family. The Houston Zoo is providing grief counseling during this time as Mac’s keepers mourn the loss of a respected and beloved member of their animal family.

Please join us in extending our deepest condolences to the members of the veterinary medical team and the primate keepers who loved and cared for Mac during his time with us.


It's A Boy! – Baby Elephant Born Overnight at the Zoo

After a pregnancy lasting almost 23 months, Shanti, a 24 year old Asian elephant delivered a healthy 385 pound male calf shortly after 2:00 a.m. today at the Houston Zoo’s McNair Asian Elephant Habitat. “The elephant keepers have named the calf Duncan,” said Houston Zoo Large Mammal Curator Daryl Hoffman.  “They like the way it sounds,” he added.
baby ele1


Attended by the Houston Zoo’s elephant care team and assisted by the Zoo’s veterinary staff, Shanti delivered the baby at 2:13 a.m. today.  “After months of preparation and tender loving care, Shanti’s labor was very brief and the delivery was  quick and easy for her” said  Hoffman.  “The keepers helped the calf to his feet and he was standing on his own within about an hour after his birth,” he added.

“The calf started nursing at 9 this morning,” said Hoffman.  “In the first 90 minutes after his first meal we saw him nurse more than 15 times.  Duncan has a very good appetite,” added Hoffman. Thai, the baby’s father, is 48 years old.

Immediately after the calf was born, the elephant care team and the Zoo’s veterinary staff performed a neonatal exam.  “We weighed and measured the calf and took a blood sample.” said Houston Zoo Chief Veterinarian Dr. Joe Flanagan. “Duncan is almost 40 inches tall at the shoulder,” added Flanagan.

babyele2Elephant keepers will keep Shanti and Duncan under a 24-hour watch for the next few weeks.   The viewing windows in the barn at the McNair Asian Elephant Habitat are temporarily closed to the public. The windows will reopen to the public after the elephant care team has seen signs that Duncan is well-bonded with his mother and is comfortable in his new home, possibly next week. Duncan is Shanti’s fourth calf.

The 8 members of the Houston Zoo’s elephant care team, assisted by the Zoo’s 4 full time veterinarians and veterinary staff and a core group of Zoo volunteers have been monitoring Shanti closely for the past 11 months.  The routine intensified over the past 12 weeks with regular ultrasounds to monitor the baby’s health and blood work to gauge the mother’s progesterone level.   Through out the delivery, Shanti was attended by the entire elephant care team and assisted by Zoo veterinarians and Zoo hospital veterinary technicians.

More than 50 volunteers and Zoo staff began a seven-day a week overnight birth watch in late-November.  Utilizing a state of the art closed-circuit television system, the birth watch team observed and documented Shanti’s behavior.  When blood tests indicated Shanti’s progesterone level had fallen to a low baseline level, members of the elephant care team and veterinarians remained at the McNair Asian Elephant Habitat around the clock watching for indications that labor might begin at any moment.


Birth Preparation Time Line 2012 – 2014

 Approximate date of conception                                        March 23, 2012

Progesterone monitoring continues                                       March 23, 2012

Transabdominal ultrasounds begin (2X per month)               Sept. 10, 2013

Transrectal ultrasounds begin (2X per month)                       Oct. 25

Birth watch volunteer training                                                 Nov. 13

Biweekly progesterone monitoring begins                              Nov. 13

Birth watch begins with Zoo volunteers                                  Nov. 23

Biweekly ultrasounds begin                                                    Nov. 24

Daily progesterone monitoring begins                                    Dec. 11

Ultrasound frequency increased if required                           Dec. 11

Elephant keepers join birth watch schedule                           Dec. 11


About Asian Elephants

 Asian elephants are herbivores. At maturity, adult males can grow up to 10 feet tall (measured at the shoulders) and weigh up to 13,000 pounds.  Adult females grow up to eight and a half feet tall and will weigh less than males.  Amazingly, despite their weight, they are able to walk silently.  Elephants are the largest land mammals in the world and among  the most intelligent animals on earth.  Unfortunately, Asian elephants are also among  the world’s most endangered species.

Approximately 300 Asian elephants currently live in North American zoos; however, a number of factors are jeopardizing their sustainability:  an aging population, low birth rates and an insufficient number—less than 30—of breeding bulls (male elephants).  Also, if cows (female elephants), are not bred by age 25, their reproductive ability is immensely diminished.  In the wild, Asian elephants typically live about 45 years.

Fortunately for the endangered species, there has been resurgence among zoos to bolster breeding efforts to help stabilize the population.  The Houston Zoo’s Asian elephant breeding program falls under the auspices of the Elephant Species Survival Plan administered by the Association of Zoos and Aquariums (AZA).

At the turn of the 20th century, more than 100,000 Asian elephants roamed their native habitat.  Today, only 35,000 remain in the wild—scattered among pockets of Nepal, India, Sri Lanka, Thailand, Bhutan, Indonesia and Vietnam.  Decades of war, an explosive human population growth and intensive agriculture continue to shrink their once abundant territories, leading to human-elephant conflict and leaving elephants prone to poaching and starvation.  Consequently, the gene pool for future generations of elephants is in a dire situation.

Baby Giraffe at the Houston Zoo!

We are proud to announce the birth of a male Masai giraffe. Mom Tyra delivered the healthy male calf shortly before 1 p.m. on Tuesday at the McGovern Giraffe Habitat at The African Forest following a 14 month pregnancy.
140204 - Baby Giraffe

“Tyra went into labor at approximately 10:45 AM on Tuesday, February 4 and delivered her baby boy at 12:49 p.m.,” said Houston Zoo Giraffe Senior Keeper Kim Siegl.  “The calf was standing on his own by 1:17 p.m. and was nursing by 1:57 p.m.,” added Siegl.

140204 - Baby Giraffe“The calf weighs 165 pounds and is 6 and a half feet tall. He’s a big healthy boy,” said Siegl.  This is 15 year old Tyra’s eighth calf.  The proud father, Mtembei is 6 years old.  With this new arrival, the Houston Zoo’s herd of Masai giraffe has grown to 9, including 5 males and 3 females.

The giraffe keepers who cared for Tyra during her pregnancy and were present for the birth will have the honor of naming the newest addition to the Houston Zoo’s giraffe herd.

Giraffe numbers in the wild appear to have plummeted by 40% over the last decade. There are currently slightly over 100 Masai giraffe living in 28 North American zoos according to the statistics available from the Association of Zoos and Aquariums. Giraffes are the tallest living terrestrial animal.  The average male is about 17 feet tall and can weigh 3,000 pounds, while an average female is over 14 feet tall.  On average, Masai giraffes typically weigh between 125 and 150 pounds at birth and stand approximately 6 feet tall.

140204 - Baby Giraffe

How the Zoo Handles Cold Weather – Then and Now

Houston winters rarely approach the category of water-pipe-busting hard freezes.  Yes, it’s happened but thankfully not that often. Still, when you’re caring for 6,000 exotic animals, some of whom find 50 degrees uncomfortable, winter preparations are essential. The Houston Zoo begins winter weather preparations early. Tropical birds are particularly sensitive to cold weather so some bird habitats are wrapped in heavy plastic and others get  wind breaks and keepers make sure gas heaters and heat lamps are all in working order.

Blue-throated Macaw-0002

But in the Houston Zoo’s early days, keeping animals warm and comfortable during the winter involved rather low tech  methodology – lots of hay for some animals, wood burning stoves for others – as this Houston Press clipping from November 1936 indicates.


Yes, that is a monkey sitting on a box in front of a pot bellied stove.  The raccoons seen at the top of the photo are being housed in the warm second floor of the Museum of Natural History which was on Zoo grounds at that time.   The Galapagos tortoise in the photo bottom left is nestled in a bed of hay having been removed from his outdoor exhibit at the first hint of cold weather and held over the winter indoors.  Although tropical birds were not included in the Houston Press’ photo montage, zookeepers in the mid 1930s employed a similar tactic to today’s Zoo to keep the macaws warm, wrapping heavy fabric curtains around the bird’s containment fencing instead of the thick fiber reinforced plastic tarps we use today.

The  photo montage was accompanied by a bit of poetry, written by Houston Press photographer Francis Miller. He had been working for the Press for 9 years when this article was published, filling mutiple roles as photographer, reporter, and even layout artist.  Miller went on to garner no small amount of fame as a LIFE magazine photographer, working in LIFE’s Washington, D. C. and Atlanta bureaus.  It was Miller who photographed President Lyndon Johnson’s beagles on the White House lawn in 1964, employing rubber bones, dog treats and a harmonica to capture their expressive faces. Miller retired from LIFE magazine in 1968 and passed away on November 5, 1973 at the age of 67, leaving behind a body of work that is still revered and sought after today.


We're Expecting! Preparing for an Asian Elephant Birth

We are preparing for a big delivery next year!  Following the back to back births of Asian elephant calves Baylor and Tupelo in 2010, we are making preparations for Shanti, a 23 year old Asian elephant to give birth in January, 2014.

“The average gestation period for an Asian elephant is 22 months,” said Houston Zoo Director Rick Barongi.  “Our nine member elephant care staff along with our four Zoo veterinarians as well as research partners at Baylor College of Medicine have been monitoring Shanti throughout her pregnancy. We’re looking forward to a successful birth and the new addition to our multigenerational herd,” added Barongi.


Young elephants Baylor and Tupelo look forward to meeting the new addition to the elephant family.
Young elephants Baylor and Tupelo look forward to meeting the new addition to the elephant family.

The Houston Zoo’s elephant care staff along with veterinarians have been monitoring the progress of Shanti’s pregnancy with regular ultrasound procedures since the late spring of last year.  Keepers have also been monitoring Shanti’s weight and her diet and leading the expectant mother through a regular exercise program.

In mid-November, training of a night watch pregnancy monitoring team made up of volunteers and Zoo employees will commence.  The team will observe Shanti via closed circuit TV cameras in the barn at the Zoo’s McNair Asian Elephant Habitat, monitoring and recording her behavior and watching for signs of labor.  The night watch pregnancy monitoring will begin in late November and will continue until the calf’s birth.

In December, daily blood sample collection to monitor Shanti’s progesterone levels will begin. A steeply declining blood progesterone level typically occurs 3-5 days prior to delivery.

The Houston Zoo is home to 7 Asian elephants including 3 males and 4 females. Shanti’s last calf was Baylor, a male born May 4, 2010.  Weighing 348-pounds at birth, Baylor was named in recognition of the unprecedented and ongoing advances made by Baylor College of Medicine’s research team to significantly reduce the threat of a potentially lethal elephant herpes virus.

Houston Zoo to Receive Federal Grant for Elephant Project

IMLS_photoThe Institute of Museum and Library Services (IMLS) recently announced nearly $30,000,000 in grants to museums across the nation.  The Houston Zoo is receiving one of the 244 awards through the agency’s grant programs.  The Zoo is receiving $459,147 through the National Leadership Grants for Museums program for a project to support the Zoo’s research partnership with Baylor College of Medicine (BCM), Johns Hopkins University and the National Elephant Herpesvirus Laboratory at the Smithsonian’s National Zoological Park which is making significant advances in the understanding of elephant endotheliotropic herpesvirus (EEHV).

Dr. Paul Ling, associate professor of virology and microbiology at BCM and Houston Zoo Associate Veterinarian Dr. Lauren Howard will travel to Washington, DC, for a workshop and ceremony on September 18, to be recognized for the award. The event will showcase the many ways museums support learning experiences, serve as community anchors, and are stewards of cultural and scientific heritage through the preservation of their collections.

“IMLS recognizes three valuable roles museums have in their communities: putting the learner at the center, serving as community anchors, and serving as stewards of cultural and scientific collections,” said IMLS Director Susan Hildreth.  “It is exciting to see the many ways our newly announced grants further these important museum roles. I congratulate the slate of 2013 museum grant recipients for planning projects that advance innovation in museum practice, lifelong learning, and community engagement.”

The Houston Zoo and its partners will conduct a research project to deepen the zoo community’s understanding of Elephant Endotheliotropic Herpesvirus (EEHV). The research will determine whether any of the currently available anti-herpesvirus drugs have efficacy against EEHV, develop sensitive tests to evaluate specific immune responses to EEHV, and continue attempts to grow the virus in the laboratory. The results of this project will be treatments for elephants with EEHV and a better understanding of elephant immunity which will inform future vaccine development.

“IMLS grants are very competitive and highly regarded in the non-profit community,” said Houston Zoo Director Rick Barongi.  “Receiving such a large grant is testimony to the critical need for more research into the most serious threat to the survival of young Asian elephants in zoos and the wild.  This grant will not only help all elephants but heighten awareness of this devastating disease so more people join the fight to find a treatment, a vaccine and eventually a cure”

Reminder: No Free Afternoon at the Houston Zoo on August 6

The Houston Zoo offers free admission to our guests on the first Tuesday of each month, September through May, from 2 p.m. until closing. June, July, and August do not have Free Afternoons.

Q: Why has the Houston Zoo eliminated the free first Tuesday afternoons between 2 and closing during the summer months?
A: Nearly 12,000 people came to the Houston Zoo in a 3 hour period on the first Tuesday in June last year (2012). Traffic on Cambridge Street was extremely congested. Houston Fire Department ambulances and other emergency vehicles use Cambridge Street to access the emergency rooms at Ben Taub and Hermann Hospitals. The heavy traffic created a potentially adverse atmosphere that could have impacted the health and safety of citizens. The Houston Zoo is committed to providing free and discounted admissions to our guests, but not at the risk of creating a potential hazard to health and safety of the people of Houston.

Q: Why is the traffic congestion such a concern? Couldn’t you just have police direct traffic?
A: Houston and Metro police and Harris County Deputies bring great skill to bear managing heavy traffic for a variety of events. But when traffic congestion reaches a certain level regardless of the traffic management skill brought to bear, delays will occur. When people need emergency medical care in the Texas Medical Center access to that care must not be delayed.

Q: The free first Tuesday afternoons during the summer are really the only time families can participate. I don’t think that’s fair.
A: We understand your concern. However, the Zoo will still observe nine other First Tuesday free admission opportunities. On average over the last two years, nearly 30,000 people have enjoyed the Free First Tuesdays between September and May.

Q: What other free and discounted admission opportunities are available at the Houston Zoo?
A: We have many and they are all listed on our website on our Buy Tickets page:

Visit the Buy Tickets webpage to browse discounts and offers

Here’s some of our many discounts. Check the Buy Tickets page for the complete list.

  • Since 1989 public and private schools within the city limits of the City of Houston have been bringing their students to the Houston Zoo for free field trips. In 2011 that meant 67,643 children enjoyed the Zoo free of charge. In 2012 more than 76,000 children participated.
  • We partner with Fiesta stores which sell discounted adult and child admissions.
  • We are a part of Bank of America’s Museums on Us program which offers Bank of America card holders a free admission on the first full weekend of each month.
  • METRO bus and METRORail riders can get a discount when they present their Q Card or fare ticket at our admission booths.
  • Rice, St. Thomas, and University of Houston students receive one free admission when they present their valid current student ID.
  • Houston Community College Students receive a discount when they show a valid current ID.
  • There is a AAA auto club discount
  • We also offer discounts for employees of the Johnson Space Center and discounts for employees of M. D. Anderson Cancer Center, Baylor College of Medicine, Kelsey-Seybold, and Texas Children’s Hospital when they present their employee ID.
  • We also offer free admission to the families of active duty military personnel and discounts to the families of retired military personnel.

Giraffe Calf, Yao, Loses Valiant Battle Against Bone Infection

February 25 – April 19, 2013

Following an aggressive course of treatment since mid-March, it is with a deep sense of loss and profound sadness that the Houston Zoo reports that Yao, a 7 week old Masai giraffe calf has lost a valiant battle against a life threatening bone infection.

This morning, Yao was sedated and Dr. Wyatt Winchell, an equine orthopedic specialist who has treated Yao since diagnosing the bone infection and the Zoo hospital staff x-rayed his right shoulder and left hip.  “The x-rays indicated Yao’s right shoulder had stabilized,” said Dr. Winchell. “However, the images also indicated degenerative joint disease and cartilage loss around the area of the hip joint, a secondary effect of the original bacterial infection which had shown indications of being resolved,” Dr. Winchell added.

“The antibiotics had performed as expected to control the bacterial infection,” said Houston Zoo Director of Veterinary Services Dr. Joe Flanagan.  “In consultation with Dr. Winchell, we determined the resulting degenerative joint disease and cartilage loss in the left hip would mean a reduced quality of life marked by life-long chronic pain,” Said Dr. Flanagan.

After consultation between Dr. Winchell, Zoo veterinarians, John Register and the giraffe keepers, Yao was humanely euthanized this morning.

One week after his birth on February 25, Houston Zoo giraffe keepers and Zoo veterinarians noticed Yao was favoring his left rear leg. Yao and his mother Neema were kept in a separate stall for observation.  When the limp gradually became worse, the Zoo veterinary staff x-rayed the leg, found no evidence of bone damage, and placed Yao on antibiotics and other medication including anti-inflammatory analgesics.

When Yao was observed limping on his right front leg, the Zoo brought in equine orthopedic specialist Dr. Wyatt Winchell of Brazos Valley Equine Hospital who determined that Yao had developed a bone infection in his right shoulder. Immediately an aggressive treatment regime began that included stronger antibiotics, arthroscopic surgery to remove infected bone, regular saline flushes of the joint and twice daily physical therapy.

Since mid-March, Yao’s course of treatment included analgesics, twice daily antibiotic treatments, regular saline flushes to remove infected fluid from his right front shoulder, and twice daily physical therapy – walks in an outdoor paddock next to the McGovern Giraffe Exhibit giraffe barn with the giraffe keepers.

“Yao was always very calm and cooperative during the procedures,” said Houston Zoo Hoofed Stock Supervisor John Register.  “We couldn’t have asked for a better patient,” said Register.  “They were performed in the giraffe barn where his mother Neema could watch from an adjacent ‘bedroom’ and she would occasionally bend her head down and lick his face during the procedures,” added Register.

“Neema was a first time mother,” said Register.  “But if there was one good thing that came out of all this it was that Neema was a wonderful, caring and loving mother to Yao. We’re certain she will demonstrate the same qualities with her future calves,” he added.

There's a hippo on a what?

Over the Houston Zoo’s 90 years, we’ve answered many calls for assistance from law enforcement agencies and animal care agencies.  The Zoo answers the call from our area sheriffs’ departments (Harris, Montgomery, Brazoria) for  exotic animal emergencies. We also have a long history of assisting the Houston SPCA with exotic animal cases providing expert evaluations of animals’ conditions and assisting with veterinary care.

But the call the Houston Zoo received on a December morning in 1986 was unique.

Houston Zoo Mammal Curator Richard Quick considers his options during a ‘hippo’ round up south of Houston in December 1986.

No, your eyes are not fooling you. This is not trick photography.  Yes, that is a young hippo standing on the front porch of a house south of Houston.

Former Houston Zoo Children’s Zoo Curator John Donaho tells us that for a time in the 1980s a circus maintained its winter quarters near Alvin. At the time, there was nothing terribly unusual or unique about that.  Houston’s relatively mild winters had made the area attractive as winter quarters for various circus operators since the 1890s.  The Christy Brothers Circus made its winter home near the city of South Houston from 1920 to 1930.

But John says when the phone rang that December morning, the Houston Zoo staff learned this call for help was a bit different. This circus had hippos and they had managed to escape their containment and were roaming free after eluding the best efforts of the circus staff to round them up.

After getting the OK from Houston Zoo Director John Werler, Houston Zoo Mammal Curator Richard Quick enlisted John and several other Zoo staff and the team took off for Alvin.  As John recalls, it took  the Zoo staffers and several members of the circus staff more than 4 hours to collect all the hippos and return them safely to their winter quarters.

We don’t know if the Zoo staff listened to Christmas music on the radio on the way back to Houston.  Maybe they all joined in a chorus of “I Want a Hippopotamus for Christmas.”

A House Call for Yao


Equine orthopedic specialist Dr. Wyatt Winchell of Brazos Valley Equine Hospital paid a house call at the Houston Zoo on Tuesday morning, checking up on Yao, the Zoo’s month old Masai giraffe who is battling a life threatening bone infection.

Assisted by the Zoo’s giraffe care team led by supervisor John Register, Yao was sedated to allow Dr. Winchell to take x-rays of Yao’s left rear hip and right front shoulder and performed a saline flush of Yao’s right front shoulder joint.

“The front shoulder joint is the location of the bone infection,” said Register.  “There is an infection in the left rear hip, but not a bone infection,” added Register.

After the x-rays were taken, Dr. Winchell performed a saline flush of the front shoulder joint. Fluid from the joint was sampled and will be cultured to assess the status of the infection.  Results of the culture are expected in a few days.

“Yao was sedated around 9: 30 a.m. When the sedation was reversed after the procedure he was up and standing by about 10:45 and nursed immediately,” said Register.

Register described the month old giraffe as stable and steady on his feet.  “Yao and his mother Neema enjoyed some quiet time outdoors in the fenced paddock outside the barn by themselves,” said Register.

“Yao is headed in the right direction,” said Dr. Winchell, who added that he is encouraged by what he saw during his house call.

“Yao is being a good patient,” said Register.  “His appetite is good and he’s gaining weight,” he added.

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