You read that right. Feng Yi, the Malaysian female giant panda, gave birth to a single cub on 14 January 2018. It is the first panda cub to be born in 2018. What’s more, her cub was born exactly two months after her first born Nuan Nuan was returned to China. Yup, Nuan Nuan is now a big sister!

A panda cub born so early in the year? Isn’t it usually around August? Did Feng Yi experience a late estrus for the 2017 breeding season, or an early estrus for the 2018 breeding season?

So many questions. First things first.

Giant pandas have a definite breeding season between the months of March and May, i.e., the spring season, every year. During those months, the females go into estrus which peak within a very narrow time frame of just 36 hours. Cubs are usually born between July and September, with late births recorded for October and November.

This was the standard for many years until a pair of giant pandas was sent to Adelaide Zoo in Australia and the female went into estrus in the second half of the year. Why did she go into estrus out of season? But she didn’t. Adelaide Zoo is located in the Southern Hemisphere where the spring season is from August to October.

So, there are actually two spring seasons, one for the Northern Hemisphere and the other for the Southern Hemisphere. Depending on where a female giant panda is living, she could go into estrus between March and May, or between August and October. With the arrival of a pair of giant pandas in Taman Safari Indonesia on the island of Java, there are now two female giant pandas living in the Southern Hemisphere.

Wait a minute. Malaysia is not located in the Southern Hemisphere but just north of the Equator. Would Feng Yi’s estrus follow the northern or southern spring? Nuan Nuan, her first cub in Malaysia, was born following the standard, i.e., northern, breeding season. Her newborn, however, was a result of an estrus that was more aligned with the southern breeding season.

Feng Yi actually missed the 2017 northern breeding season because Nuan Nuan was still with her and still nursing at the time. So how come she went into estrus during the 2017 southern spring season?

My first thought was maybe Feng Yi’s mind migrated south and persuaded her body to go into estrus at that time of year. Or maybe she went into estrus in sympathy with her sister-in-law, Fu Wa’s twin Fu Ni, who lives in Adelaide Zoo. Yes, I know, silly thoughts both.

It could very well be that she experienced a late estrus and papa Fu Wa was in sync with her at the same time. The Malaysian panda team has a part in this, too; when they saw she was in estrus, they monitored her. When her estrus peaked, she was put with Fu Wa, and they mated, even though it was later than the usual northern spring season.

The real reason, however, could be the panda complex where they live. Since Malaysia is too hot for Fu Wa and Feng Yi to spend time outdoors, they live 24/7/365 inside the panda complex which is temperature-controlled to provide an environment similar to their home in China. But it is an indoor environment where they don’t get natural light and air. Without these indicators, maybe, over time, they are less able to sense the changing of seasons necessary for their bodies to go through the same changes as back home. As a result, Feng Yi’s body went into estrus at the “wrong” time according to the norm but it was the right time according to her. That’s what I think, anyway.

Whatever the reason, Zoo Negara Malaysia now has the distinction of having the first-born giant panda cub of 2018. We didn’t have to wait for the 2018 breeding season to begin, and to wait another few months to know if papa Fu Wa has met his KPI again. He already has.

As to the question whether Feng Yi experienced a late estrus for the 2017 breeding season or an early estrus for the 2018 breeding season, the answer is neither. It’s just Feng Yi being Feng Yi, following her body’s wishes.