I couldn’t wait to get to work this morning! My excitement surrounded yesterday’s developments at the cheetah breeding facility at the San Diego Zoo Safari Park. Our young, inexperienced female cheetah, Lindiwe, has been showing signs of estrus, and at long last our experienced male cheetah, Noka, has taken an interest in her. This is a very exciting development in the world of cheetah breeding!
I grab my raincoat and notebook and head over for more cheetah watching. Our breeding facility is not accessible to guests. After arriving, I try to control my excitement and optimism about the possible outcome of today’s breeding attempt. I’m pretty sure today is the day that Lindiwe and Noka will breed successfully.
My hopefulness increases as I view a short video recorded by our animal care staff just hours earlier, showing positive signs of interest between Lindiwe and Noka. These include both cheetahs laying down next to each other in their adjacent enclosures and touching noses through the fence. Noka then proceeds to make a vocalization called a stutter-bark in Lindiwe’s direction. The stutter-bark is a rarely heard vocalization primarily used by male cheetahs in breeding situations. We believe the stutter-bark plays a significant role in a male cheetah’s attempt to breed a female.
Listen to a cheetah stutter-bark:
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To better understand the possible role of the stutter-bark vocalization, a little background on cheetah reproduction is needed. In most mammals (including humans), the release of eggs happens spontaneously and predictably (with cycles of varying length). However, there are a number of species that possess a different type of reproductive strategy where eggs are released from the ovaries after some sort of stimuli but not on a predictable cycle. The stimuli could include the physical act of mating, among many other possibilities.
In cheetahs, the stimuli that lead to egg release are not clearly understood. In the wild, female cheetahs are predominantly solitary, so we think that when a male encounters a female, the stutter-bark vocalization may be part of the reproductive strategy to help bring a female cheetah into estrus.
Our team moves Lindiwe to a neighboring enclosure while Noka is brought into Lindiwe’s enclosure, which he thoroughly investigates by patrolling the area, sniffing, and spraying. While he is investigating, we record details about both cheetahs’ behavior. We are hoping for a “strong” behavioral response from them, including both cats being very focused on each other, the female rolling on the ground and flicking her tail. Most of all, we are hoping that she won’t be aggressive toward him and that Noka will stutter-bark while pacing her fence line.
The breeding attempt continues for approximately 30 minutes, during which time we see the positive signs we are hoping for from both cheetahs. We decide to attempt an introduction between Noka and Lindiwe. At this point we’re also considering the possible downsides of an introduction with a female cheetah that may not be in estrus and, as a result, can be unpredictable and aggressive. This is definitely something we do not want in a breeding situation! Having weighed the costs and benefits, we move forward with our introduction: a keeper opens a fence separating Lindiwe and Noka while I continue observing and taking notes.
The breeding attempt begins positively, with no aggression from the male or female. Lindiwe is active and moving while the male stutters quietly toward her. He begins to follow her but occasionally gets a little too close, resulting in Lindiwe turning and moving toward him slightly. Then she turns and continues to walk around the enclosure. Noka is somewhat focused on her but is also not responding very strongly and appears to be somewhat distracted. After some time, we decide that the male’s response is not adequate and reluctantly separate the cats in the hope for a better response tomorrow.
If Lindiwe is truly coming into estrus, we expect to see a much stronger response from Noka. We do not currently have a scientific test that will tell us if Lindiwe is in estrus on the day of the introduction. If we attempt a blood draw, the possible stress associated with the procedure could affect the female’s reproductive hormones. Our current approach is to noninvasively examine Lindiwe’s reproductive hormones by collecting her fecal samples and determining her hormone levels back at the Behavioral Biology endocrinology lab. Stay tuned for my next blog post detailing the laboratory approaches I use to determine reproductive hormone levels in cheetahs and my determination (via hormone levels) of whether Lindiwe was truly in estrus during this breeding attempt.
Corinne Pisacane is a senior research technician in the Behavioral Biology Division of the San Diego Zoo Institute for Conservation Research.
What other animals breeding behaviors requires some sort of stimuli to bring on estrus? Is there a name for this?
Good luck with the Cheetahs!
Thank you!
Hi Dianna,
Thanks for your comment and very good question. In most animals, estrus and ovulation happen spontaneously. But in a few animals, ovulation is induced, as in cheetahs. This doesn’t necessarily mean that cheetahs need a stimuli to bring on estrus. We believe they naturally go through a type of “cycle” where eggs and follicles develop in their ovaries and get close to being mature enough for ovulation. When this “cycle” reaches its peak, that would represent estrus in cheetahs. We are trying to accelerate this process by using a playback of a male cheetah stutter-bark in the beginning of our breeding attempt. We hope this stutter-bark will bring on female estrus quicker so we can save time in our breeding attempts.
Female animals will naturally come into estrus when they are ready to breed, but it’s unclear what stimuli might aid or bring about their estrus. It’s a really great question, and thanks for asking!
Thanks for this blog Corinne. I of course know nothing about cheetah breeding but found this very interesting.
It is too bad that all the animals don’t come with an instruction manual. Life would be so much easier for you and your team then. I hope the next meeting of these two make all the work you do have the result you and we all want.
Thank you Corinne for an informative blog on the cheetah breeding approach and look forward to your updates on the process.
Cheetahs are my absolute favorite animal, and I was fortunate enough to view a Cheetah run at the SD Safari Park a few years back and was blown away by their speed and grace. Having one only a foot away for pictures will be one of the most memorable experiences of my life. I can’t tell you how thrilled I was to be in the presence of such a magnificent, beautiful animal. You have a job I’d take in an instant! I’ll keep my fingers crossed and hope for some cubs next year!
thanks. that does sound exciting. good luck for a successful breeding.
Fascinating blog! I hope Noka’s stutter bark will successfully woo Lindiwe into her estrus and their next encounter will have the romantic behavior you are looking for. I’m sure you were relieved that this first introduction went calmly without aggression by either cat. Guess they need a few more nose rubs before they get to the more serious action. LOL. Good luck the next time. We can never have too many cheetahs. They are such beautiful cats.
Thanks for the sound clip. Keeping my paws crossed for successful breeding.
I tell you I think some cat nip, a few femur bones and some berry white will do the trick!