Estrus in Earnest
Posted at 1:17 pm April 20, 2007 by Suzanne Hall
Bai Yun is now officially in estrus! Our latest laboratory results reveal that as of April 13, her hormones crossed a threshold delineating estrus from pre-estrus. She is now showing a nice hormonal incline towards a peak that will likely result in ovulation—and a mating window—sometime between April 23 and 25. As a result of these hormonal changes, her vaginal cytology now signals a similar trend, indicating a probable ovulation date of April 25. As tricky as her estrus has been thus far this year, it will be interesting to see if her schedule from here on out will follow our predicted models as closely as it has in years past. Will she truncate, and breed over the weekend? Frankly, I want to know as much as you do!
We have finally started to see some behavior signaling that the hormones are having an effect. As of yesterday, she is starting to lose her appetite, has begun scent marking, and is interacting with water more frequently. Gao Gao has yet to respond to these changes in her, though he is keeping a close eye out. After his initial whirlwind days of excitement once the howdy gate was opened, he settled into a routine of checking the gate many times a day, sometimes calling to Bai Yun with soft bleats. With no response from her, Gao Gao would settle for a nap near the gate, often where he could see her while he rested. He’s being very patient, and soon that may pay off.
Bai Yun’s handlers have begun testing her for mating receptiveness using a very simple test. When our girl is brought into the back each morning to check her weight and get a urine sample (which she has been trained to offer on command), the keepers now use a slim piece of bamboo to perform a “tail-up test.” They use the bamboo to simulate the touch of a male who may be trying to mount, and apply pressure with it to the region of her lower back above the tail. When she closes in on her peak of estrus, such a touch will elicit a tail-up response, a flicking of the tail that seems to be a reflex in response to the touch. At her peak, the tail-up response becomes very strong, with her holding her tail high for several seconds, often backing up in the process. This type of behavior facilitates the mating process when the time is right. Thus far, Bai Yun’s response to the tail-up test is to sit down, which certainly wouldn’t help Gao Gao achieve the correct mating posture with her. Obviously, she is not yet at her peak!
I encourage everyone to come see Bai Yun in estrus over the next few days. It’s a fun time to watch the pandas, who usually are much more sedate, and it’s a rare occurrence around here since Bai Yun and Gao Gao have been so successful in producing cubs. If they succeed again this year, it will be at least two years before this happens again. This may even be the last solid estrus Bai Yun ever has, as the aged females have atypical, unpredictable cycles as they get older.
A word of note: once Bai Yun peaks and we are ready to pair the bears for mating encounters, we will close the exhibit. No visitors will be allowed in the queue during breeding attempts. This is largely because the queue is full of staff that is manipulating the enclosure gates from the queue, watching the bears to make on-the-spot decisions, and recording data. When mating is underway, we will open alternative areas of the panda facility for viewing Su Lin in her classroom exhibit.
Suzanne Hall is the senior research laboratory technician for the Giant Panda Conservation Unit of Applied Animal Ecology/CRES.
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April 20th, 2007 at 1:44 pm
The plot thickens. Sounds like it is getting really exciting. All I have observed today is Bai Yun sleeping and GaoGao eating. Getting their energy ready for the big moment I think.
For those who have been waiting to see Su Lin since she is a Princess in her own “castle” your chance sounds like it is days away. I hope as many of you as possible get to the zoo this weekend and catch all the pandas in action as the animals on exhibit are re-directed to the youngsters once again.
If a mating takes place in the next week, when will it be likely that Mei and Su can be placed back in rotation to exhibit 2 so their admiring fans can get to see them again? It has been a long time for patient zoogoers.
April 20th, 2007 at 1:48 pm
With all the discussion of Pandas and their favorite Springtime treat of shoots, has Bai been eating many leading up to estrus. I have read that some research suggests that panda’s fondness for shoots in Springtime may be because they are possibly more nutritious than the normal stalks, culm, and leaves that they eat the rest of the year. The shoots may provide added nutrition that helps with mating, and cub development. Even Mai Lan has discovered them and likes to chew them up.
Does Su Lin show any preference for the succulent shoots as opposed to the steady supply of bamboo she has learned to eat? The boys seem to eat whatever is put their way to keep them from starvation and in good healthy condition.
April 20th, 2007 at 2:03 pm
Thank you Suzanne.
April 20th, 2007 at 2:17 pm
WOOHOO!!! Here We Go….Good luck Bai and Gao and also to all the Panda Keepers, how exciting…
April 20th, 2007 at 2:39 pm
I’ll be there at 9:00 a.m. sharp!
April 20th, 2007 at 2:49 pm
How exciting! Thanks for the updates.
How is our lovely lady doing on her weight? Has her break brought her a few more pounds?
I love your description of what Gao Gao is doing - such a great Romeo, so patient, always checking, staying nearby at the ready… gotta love him!
Another question - where will the panda cam be focused during all the excitement?
Fingers crossed!
April 20th, 2007 at 4:11 pm
That’s the best news I’ve heard all week! Good luck to all!
April 20th, 2007 at 4:19 pm
Many thanks for your welcome and informative update on the progression of Bai’s estrus.
I am very pleased that it is highly likely Bai Yun and Gao Gao will mate again in the next few days, seems likely Bai’s ‘water walking’ pm. on the 14th April was the start of her campaign to woo Gao Gao!!
I am keeping my fingers crosssed that everything goes according to plan and you will shortly advise us that a mating has taken place.
If so is it likely to be backed up with AI?
Congratulations to everyone at SDZ who lavish so much care and attention on the Panda’s……..
April 20th, 2007 at 4:33 pm
That is so exciting! I have been watching a bit and did see Gao Gao by the howdy gate at one point. I can’t wait to see what happens. I have become so interested in watching all of the pandas. I admit I peek in daily since I’m no where near San Diego. Hope to get there sometime and see the beautiful animals for myself. Good Luck!
April 20th, 2007 at 4:34 pm
thanks for the update. that part about Bai sitting down at the tail up test is so funny. i can just imagine her doing that. Bai anwsers to no one. except for her casanova Gao Gao.
April 20th, 2007 at 5:39 pm
I will keep my fingers crossed that they succeed in their endeavors!
April 20th, 2007 at 5:46 pm
Thank You for this update! How very excited you all must be about the possiblities in the days to come! What fine Panda babies Gao and Bai have made; now the real thought that they may create yet another perfect panda is filling me with joy! You All keep us so well informed; the writings are appreciated! Did the Bears have fun in the rain today? And Thank You for having the cameras on Su Lin and Mei Sheng this week:)
Sincerely, Bobbie Wood
April 20th, 2007 at 5:51 pm
Fascinating! Every day I learn something new. Keep up the good work.
April 20th, 2007 at 5:54 pm
I appreciate your updates and all the nitty gritty details! I read everything I can about pandas, but you guys provide the best insight, making me feel as if I am standing along side of you.
Many, many thanks,
Jamie
April 20th, 2007 at 6:04 pm
Thank you for the detailed update on Bai Yun’s estrus and the behavioral changes to come. Im a panda fanatic and have been concerned that Bai may not have one this year. Bai Yun is my ‘gal’ and Gao Gao my ‘guy’ and I’m always interested in their health and activities.
If mating is sucessful, I’m sure Bai Yun and Gao Gao will present us with a third beautiful, happy and healthy cub - of course mama’s fourth! It would really be nice to add to the family this year and have all five pandas at the zoo at the same time, before Mei Sheng returns to China. Also, I’m watching Mei Xiang, at the National Zoo, in hopes that the AI was successful and Gao Gao will become the first bi-coastal panda dad in the U.S. You have to watch the quite ones - Gao Gao is an unassuming, no-nonsense guy - but what a dynamo!!!
I’m going to try to get to Panda Canyon early next week to check on my bears. Thanks again.
April 20th, 2007 at 7:31 pm
I appreciate the zoo keeping me updated on the pandas. I am an True Panda lover. I was in a store here in Montgomery, Alabama, lo and behold, I was looking at an Panda Throw. I could not believe it. That is one thing, that I did not have in my collection.
I have a room just full of Pandas and accessories. That are having all kinds of parties, and they didn’t even invite me. LOL!!!!!!!
Enjoy reading the information that you send. Keep up the good work. I am hoping I will be able to make it out to San Diego this yr. My cousin lives there.
Thanks again.
Susan McNeal
April 20th, 2007 at 7:55 pm
This whole pand thing is so amazing! Thank you all for your tremendous hard work to insurewe have pandas to enjoy in the future!
April 21st, 2007 at 12:09 am
Ahhhhhhh love is in the air for Lady Bai and Sir Gao! I am so happy and excited for them both, and for all you wonderful folks at SDZ who take such wonderful care of our beloved panda family. Best of luck to you all….I have all my fingers and paws crossed, and sending good vibes westward to Cali and the lovebears!
April 21st, 2007 at 6:20 am
I am 70 years old but love the panda’s so much. I have loved them since I was a little girl and even though I live many miles away I love the video cam and enjoy it almost everyday. I hope you all have great sucess with the mating. What a wonder it must be to work with these wonderful animals. My grandson Tripp who lives in Marietta, Ga. dreams of one day working as a vet or whatever at the zoo there. I saw the panda’s in Washington D.C. many years ago and what a treat. I am not overly religious but I know God worked a little wonder on these beautiful creatures. Bless you ALL in your endevers and great sucess in getting a new little.
April 21st, 2007 at 8:04 am
Hi Suzanne,
Great News! — Looking forward to visiting our beautiful Pandas this coming week. I found your update regarding Bai Yun’s testing both fascinating and very informative. If we find the exhibit closed, we’ll be elated knowing Bai & Gao are together. Also, we will be happy to once again visit with our “sweetie” Su Lin. It will turn out to be a win/win for us.
Regards, and many thanks to you and everyones hard work and patience at this time.
Rose N.
April 22nd, 2007 at 8:05 am
patience is a virtue and big daddy has plenty of it. hope he gets his reward soon. I have a question, will you AI Bai if no natural breeding takes place. I asked this because she is supposed to be returned to China next year per the loan agreement and if she has a cub or two they would be very young to travel and also Su LIn would be returning to China next year. whould we be getting new pandas? just a note on the issue of global warming. Our local t.v. has been doing a piece from every continent for earth day and it features all the effects on animals. such as polar bears and birds and all the animals that face extinction. hope this wakes up alot of people
April 22nd, 2007 at 9:14 am
What fascinating and exciting news! Thank you so much, Suzanne, for explaining the process of the estrus in so much detail. It sounds as if Bai Yun is nearly “there”. Good luck to Bai Yun and Gao Gao who sounds like a real gentleman. I am sure his patience will pay off! Being involved with these lovely creatures it must be wonderful for you and all the other staff to follow Bai Yun’s estrus peaking. I wish all of you lots of success in catching the “small mating window” of Bai Yun and, thus, hopefully ensuring another offspring (s). Thank you for all your dedication!
April 22nd, 2007 at 12:57 pm
Let’s hope that Bai Yun is ready to mate soon!
April 22nd, 2007 at 5:44 pm
What a polite and patient gentleman, our Mr. Gao Gao. I visited Gao Gao and Bai Yun Sunday around noon, and there he was eating his lunch close by the howdy gate. He’d stop eating every so often, go to the howdy gate, leave his calling card, and return to his lunch post and consume another stalk. Then, he’d roll around in the dirt, and sing a song, hoping, I am sure, that his girl across the gate would be listening. All the while, Bai Yun was chowing down, no appetite loss during this particular meal. She looked beautiful as always and appeared quite content with the pile of bamboo surrounding her. And here we are, watching every move, listening for every sound–wondering how and when all of this might lead to those precious moments we hope for. Time will tell, but in the meantime, I continue to be thankful that I can witness all of this and continue to learn about these incredible animals. What treasures!
April 23rd, 2007 at 12:55 pm
Thanks Diana for a first-hand account of your visit on Sunday. Let’s hope GaoGao’s behavior around the gate indicates that Bai Yun is “progressing.” Meanwhile she just has to sit and wait, and eat enough to keep her body bulked up for the whole process.
April 24th, 2007 at 6:31 am
ah love is in the air or something is in the air, I was checking in on our D.C. family yesterday and boy were they going crazy. Tai was in and out of the water running and climing and acting like a gymnast in the trees. everyone here was laughing for a good 5 minutes. later in the day Mei was walking in and out of the indoor enclosure and being very vocal,she was scratching and sitting in the water and just plain pacing for a good hour. Yesterday was the first time i have seen something get Tai’s attention at the veiwing window because he sat and looked at all the children that were sitting at the ledge. It seem that yesterday was a great day for all our Bears. Bai please you are making me nervous and that’s when i start to eat. Not Good Sweetie.
May 12th, 2007 at 6:01 pm
i wonder there will be will be girls or a boys or both that gao gao and bai yun will have ! its so exciting!!:O
June 2nd, 2007 at 6:05 pm
I was watching Gao Gao eating bamboo via pandacam around 5:50 p.m. on 6/2/07. After a few minutes, he got up, walked a few steps and dropped dudus on some bamboo on the ground. Does that mean he is done with the stack of bamboo and not coming back to eat at the same spot?
June 4th, 2007 at 9:50 pm
After posting my question on 6/2/07, I went back to pandacam. Gao Gao was back at the pile of bamboo, only a few feet away from his dudus, eating away!! I am loosing respect for pandas. Why didn’t he go away from his food to dudu if he was going to come back to eat??