Tokyo's Ueno Zoo halted public viewing of two giant pandas on Wednesday after it emerged female panda Shin Shin appears to be in heat.
The zoo, in Taito Ward, is preparing to house the two pandas, Shin Shin and male panda Ri Ri, both 11 years old, together in the hope that they will mate. The two pandas are normally housed in separate enclosures.
According to the zoo, Shin Shin has been attracted to the scent of Ri Ri, while Ri Ri has also been displaying actions that seem to indicate heightened sexual desire.
The two pandas are expected to start living in the same enclosure within several days.
In 2012, a cub was born to Shin Shin and Ri Ri but died after six days due to pneumonia. In 2013, Shin Shin showed signs that she was pregnant, but it was not the case.
Since 2014, the two pandas have not mated.
Panda breeding season runs from February to May, though conception is only likely for a few days within this time frame, experts say.
The zoo is considering artificial insemination if the pair don't conceive this time.
