Category — Exhibits
Many visitors to the Zoo have met our two African lions, John and Imani, in the new Africa exhibit. These two young cats were paired up earlier this year with the hope that they would breed and produce their first litter of cubs in the near future. The good news is that breeding activity has been observed on several occasions this past year, and, after at least one pseudopregnancy, it appears that Imani is now pregnant and due to give birth within the next month. Which raises the question – how do you diagnose pregnancy in a lion anyway?
Scientists at the Zoo’s Center for Conservation and Research of Endangered Wildlife (CREW) commonly use three methods for pregnancy diagnosis in wildlife species: ultrasonography, fecal progesterone analysis, and urine relaxin analysis. Ultrasonography remains the gold standard since visualization of a fetus with a strong heartbeat is the definitive proof of pregnancy. CREW frequently uses abdominal ultrasonography to diagnose and monitor pregnancies in our domestic cats (see below). However, this method can be challenging to apply with a potentially dangerous carnivore, like Imani. Through the Zoo’s operant conditioning program, Imani eventually may be trained to allow voluntary abdominal ultrasound exams, but this method is currently not an option with her.
The second approach for pregnancy diagnosis is the use of fecal progesterone analysis. Lions, like other felids, show an increase in fecal progesterone levels shortly after ovulation that is detectable using CREW’s hormone assays. If lions ovulate but don’t conceive, they will have a pseudopregnancy that lasts 50 to 60 days and then progesterone will decline back to baseline levels. If progesterone concentrations stay elevated beyond 60 days post-breeding, then the female is most likely pregnant. Imani’s fecal hormone profile (below) shows progesterone levels increasing coincident with her last breeding activity and staying elevated through at least 66 days post-breeding (the last fecal sample tested).
The third option for pregnancy diagnosis involves measurement of another hormone, relaxin, that is produced by the placenta and excreted in the urine. CREW has helped to pioneer the use of a bench-top relaxin test for pregnancy diagnosis with urine from cats. Our previous research has found that pregnant domestic cats and Pallas’ cats produce high levels of urinary relaxin that are detectable with the bench-top test, but pregnant cheetahs and clouded leopards apparently do not. Imani is the first lion that we have evaluated late in a suspected pregnancy. Urine samples collected from Imani at day 73 and 74 post-breeding were both positive for relaxin (below, circled line in window #2), providing further presumptive evidence of an ongoing pregnancy. In the absence of a sonogram showing a viable fetus, the positive results from the progesterone and relaxin assays provide our best evidence that Imani is pregnant.
Hopefully, Imani will confirm our diagnosis in the next few weeks with the anticipated birth of her first litter of cubs. Since Imani will be a first-time mom, she will be provided with a quiet, off-exhibit den area to give birth and bond with her cubs, and likely will remain off-exhibit until early spring when the cubs are a bit older.
October 28, 2014 No Comments
You probably already know that the Cincinnati Zoo is committed to the conservation of lions, tigers and cheetahs, but did you know that we are also leading the way in small cat conservation? And our Small Cat Signature Project just got bigger! Our Center for Conservation and Research of Endangered Wildlife (CREW) recently received a Museums for America Grant from the Institute of Museum and Library Services to improve our ability to maintain healthy captive populations of five small cat species across the country—the Brazilian ocelot, the Pallas’ cat, the black-footed cat, the Arabian sand cat and the fishing cat.
Unfortunately, none of these small cat populations are considered sustainable through natural breeding alone. That’s where Dr. Bill Swanson, CREW’s Director of Animal Research and the world’s leading expert on small cat reproduction, comes in. Working in partnership with Dr. Jason Herrick of the National Foundation for Fertility Research and the Species Survival Plan coordinators for each species, Dr. Swanson will direct the project with a focus on three goals: 1) Collect and freeze semen from the most valuable cats for each species, 2) Produce viable offspring using artificial insemination in recommended breeding pairs that fail to reproduce naturally, 3) Produce offspring with frozen-thawed semen from genetically valuable or under-represented males.
Building on CREW’s decades of ground-breaking research on small cat reproduction, successful completion of this project will greatly enhance the sustainability and stewardship of small cat collections in AZA zoos. Now that’s big news!
October 9, 2014 1 Comment
If you are a frequent visitor to the Zoo, you might have noticed a new addition to our Andean condor exhibit as of late. With the tremendous help of some extremely dedicated volunteers, the Aviculture Department was able to research, help build, and install a nesting chamber for our breeding pair of Andean condors.
Background on the birds:
Like other vultures, Andean condors act as nature’s recyclers! Befitting their role of scavengers, condors have several physical adaptations to help them clean up the environment. Their strong, hooked beaks aid in holding and ripping food, while the lack of a well-feathered head minimizes contamination when dining upon carcasses. Not-so-obvious on the outside, the condor’s extremely strong and resilient digestive system is able to break down bone to obtain much-needed calcium as well as to kill the toxic bacteria that cause anthrax and botulism. All of these facets certainly reveal the condor’s important role in maintaining healthy, well-balanced environments.
Like many other long-lived (over 70 years) and slow-breeding (one chick every other year) species, however, the Andean condor is having some trouble keeping its own population in balance in the wild. It was first listed by CITES as endangered on July 1, 1975. Andean condors are currently listed as Endangered by the U.S. Fish and Wildlife Service and Threatened by the International Union for Conservation of Nature. This species historically had a significant range in South America, from Colombia and Venezuela to the Strait of Magellan and Tierra del Fuego. They are exceedingly rare in the northern ranges of South America, and are most frequently sighted in Colombia, Venezuela, Peru, Chile and Argentina. The condor is still subject to persecution by poisoning and gunshot over most of its home range, and it has been historically difficult to monitor the population in the wild according to the AZA Andean Condor Care Manual (2010).
The Cincinnati Zoo has participated in conservation efforts involving both the Andean condor and its even rarer cousin, the California condor, since 1989. Along with participating in the captive breeding program, the Zoo has also served as a staging area for North American-hatched Andean condors destined for release in their native country of Colombia. Juvenile condors and breeding pairs are housed at our off-site facility where they are conditioned for release into the wild. In the summer of 2013, a breeding pair of Andean condors was transported from the Zoo’s off-site facility to Miami, Florida, where they boarded a plane bound for Colombia. We have been ecstatic to hear reports from the Andean Condor Species Survival Plan that birds we have held here at the Zoo have produced chicks in the wild!
How can we increase the chances our condors here in Cincinnati will have a family of their own? Both of our birds – “Laurel” and “Gryph” – celebrated their 32nd birthdays this past June, so they are well within breeding age. They have lived in their display overlooking Wildlife Canyon since 2008, so should be well-settled. (Note: They first came to us when they were very young, left the Zoo in 1998, and then returned to us in 2008.) Since that time, we have recorded a lot of success with pair-bonding and copulating, and even with laying at least one egg per year, but unfortunately this pair has never successfully hatched out and raised a chick.
The idea of building a large protective nesting box that could mimic the wild cliffside caves the birds prefer as well as reduce the chances of egg breakage during the incubation process was formulated.
Background on the box:
Andean condors typically stand around four feet tall and can weigh up to 33 pounds. Thanks to its massive wingspan of 10.5 feet, this species can rightly claim the title of the largest flying land bird in the Western Hemisphere. Taking their overall size, enormous wingspan, and hooked flesh-tearing beak all into consideration, I knew this would need to be –by far– the largest and strongest nesting box we had ever embarked upon the creation of here at the Cincinnati Zoo!
Research and guidance provided by Aviculture Curator Robert Webster was critical in the development of a blueprint for our new Condor Condo. With a game plan in place, lumber, hardware and stain was purchased and transported to our most crafty carpenter, Mr. Bill Rettig, one of the Zoo’s Bird House and Manatee dive volunteers extraordinaire.
Bill worked out of his basement and garage during the construction process, while his wife generously gave up her indoor parking space! He also enlisted the help of several other family members and neighbors in the nest box building and installation process. Lucky for him, there are several engineers and mathematicians in the family. With the completed project weighing in easily over 300 lbs and measuring over six feet wide and six feet tall, this was truly a group effort!
What the keepers will be looking for this winter:
As part of their mating rituals, Andean condors typically perform courtship displays such as walking back and forth with outstretched wings and making hissing and clucking sounds. The male usually initiates this ritualized courtship display, approaching the female with his body upright, his neck arched, inflated and more intensely flushed with red, and with his wings fully open in a forward-curving arc. He walks stiffly, swaying from side to side. Initially he may make a hissing sound, similar to air brakes on a truck, followed by a deep, repetitive drumming sound that has been compared to a helicopter. If the female is interested, she will remain near him and may bite at his neck or wings, although not aggressively. Females may also engage in the wings-out courtship display, although typically not as elaborately or for as long as the male.
Andean condors are sequentially monogamous in the wild, often remaining with the same mate indefinitely. Eggs may be laid between March and June and fertility for established pairs is typically very high. Males and females share both egg incubation and chick rearing duties roughly equally. The egg incubation period for this species is 58-62 days.
Special thanks to Bill for his undying enthusiasm for this project, and his family for jumping in to help without question, even though nest box installation was a stinky, sweaty, tough job! Ultimately, success in collective Andean condor management and care will allow AZA-accredited institutions to contribute to Andean condor conservation and to ensure that Andean condors are helping to clean up the Earth we all share for generations to come.
September 23, 2014 No Comments