Scientists blamed the cold start to the year for slowing down female Tian Tian’s hormone levels, but the bear showed clear signs this weekend that she was about to reach her breeding peak.
Seemingly aware from Tian Tian’s signals that his big moment was approaching, Yang Guang could be seen staring into her enclosure in the sunshine yesterday. The pair met briefly in a shared enclosure in the morning.
A zoo spokeswoman said last night:“Tian Tian continues to progress both behaviourally and hormonally and we do not have much further to go to peak. When she gets there we will begin introductions between the two pandas and the breeding window of 36 hours will begin.”
Once Tian Tian starts her 36-hour fertile period, the pair will meet in an enclosure up to three times for short 15 to 30-minute intervals, following the pattern of how pandas get together briefly in the wild to mate and then separate. Giant pandas only mate when the female is in season.
Iain Valentine, director of giant pandas at the zoo, and Alison Maclean, head panda keeper, are among those overseeing the mating programme.
The team has been joined by a specialist from the China Conservation and Research Centre for Giant Pandas and experts on artificial insemination and reproduction management from the Leibniz Institute for Zoo and Wildlife Research in Berlin to assist in ensuring that Tian Tian has the best chance of becoming pregnant.
Artificial insemination will take place regardless of whether natural mating occurs.
As soon as Tian Tian hits her peak, her hormone levels will start to fall and artificial insemination is expected to take place very soon afterwards.
Zoo staff say they will know via ultrasound scans in late July or early August whether Tian Tian has become pregnant.