Extracting the urine from a bear

Panda cubs are exceptionally cute, but in Edinburgh, increasing the chances of two giant panda parents reproducing is no mean feat.

Edinburgh Zoo is hoping that its resident giant pandas, Tian Tian and Yang Guang, will mate soon, and the bears are being closely monitored as Tian Tian enters her short fertile period. Writing on theconversation.com this week, scientist Forbes Howie from the University of Edinburgh went into detail about monitoring urine samples from Tian Tian.

"We are looking at the oestrogen levels, which rise near the time of ovulation, " he writes. "Once Tian Tian ovulates and the egg is released, that's the prime time for her to mate."

But getting the samples is not without its perils. Tian Tian’s habits are changing, according to Howie: she is urinating outside her usual spot in the den, and the bears are not to be toyed with.

“They look cuddly, but the keepers warned me not to put my arms through the bars because they could quite easily take your arm off,” he writes. “This makes it harder to collect those urine samples. If she pees in the wrong place and doesn’t move away, the sample soaks into the earth and is lost.”

The keepers have been monitoring Tian Tian on CCTV cameras. “As soon as she’s peed, they try to get in to suck it up in a syringe so that it can be sent to my lab for analysis.”

But there are positive signs. Last week the zoo reported the giant pandas were “one step closer to the anticipated 36-hour annual breeding window, with experts confirming a crucial hormone crossover in female panda Tian Tian has now taken place and that she should come into oestrus in the next seven to 14 days”.