Urine analysis has started and Calgary Zoo officials will soon renew training so Er Shun, a female giant panda, will accept ultrasound examinations to help determine whether she is pregnant.

Er Shun was artificially inseminated in April, and despite the ongoing observations, officials say they won’t know for sure whether she is pregnant until a heartbeat can be detected, usually about two to three weeks before she gives birth.

Gestation for giant pandas is three to five months and pandas can experience what’s known as delayed implantation in the uterus, meaning it could be August before officials can be certain.

Adding to the difficulty is the fact newborn giant panda cubs typically weigh about 90 grams, which is only 1/900th of their mother’s weight, making them the smallest placental mammal baby on earth in proportion to its adult size.

Along with Calgary Zoo staff, a specialized team is also here from China assisting.

The abdominal ultrasounds will be used to detect any enlarging of the uterus and urine analysis will look at hormone levels, another possible indicator of pregnancy.

A nursing den at Panda Passage is also being prepared.

“The value of breeding these international and vulnerable symbols of conservation is a tremendous opportunity to engage our community in making a difference for wildlife in Canada and around the world,” said Calgary Zoo president and CEO, Dr. Clément Lanthier, in a release.

“We believe that small actions often lead to big changes that help sustain the incredible biodiversity on the planet.”

There are currently four giant pandas at the Calgary Zoo. Adults Er Shun and Da Mao arrived at the Toronto Zoo in March 2013 and she gave birth to two cubs, Jia Panpan and Jia Yueyue, later that year, making them the first giant pandas born in Canada.

They arrived in Calgary in March 2018.

Er Sun and Da Mao are expected to remain here for another four years while her cubs are expected to be returned to China this fall.

There are fewer than 1,800 pandas living in the wild.