Staff members help a doctor to carry out a B-scan ultrasound examination for a pregnant sea lion at Harbin Polarland in Harbin, capital of Northeast China's Heilongjiang province, Aug 2, 2016. Harbin Polarland invited a doctor of ultrasound department of the No 2 Hospital Affiliated to Harbin Medical University to examine the sea lion, which is expected to deliver a baby at the end of August. [Photo/Xinhua]
 

Staff members help a doctor to carry out a B-scan ultrasound examination for a pregnant sea lion at Harbin Polarland in Harbin, capital of Northeast China's Heilongjiang province, Aug 2, 2016. Harbin Polarland invited a doctor of ultrasound department of the No 2 Hospital Affiliated to Harbin Medical University to examine the sea lion, which is expected to deliver a baby at the end of August. [Photo/Xinhua]

Photo taken on Aug 2, 2016 shows B-scan image of a sea lion fetus in an examination for a pregnant sea lion at Harbin Polarland in Harbin, capital of northeast China's Heilongjiang province. Harbin Polarland invited a doctor of ultrasound department of the No 2 Hospital Affiliated to Harbin Medical University to examine the sea lion, which is expected to deliver a baby at the end of August. [Photo/Xinhua]

A staff member helps a doctor to carry out a B-scan ultrasound examination for a pregnant sea lion at Harbin Polarland in Harbin, capital of northeast China's Heilongjiang province, Aug 2, 2016. Harbin Polarland invited a doctor of ultrasound department of the No 2 Hospital Affiliated to Harbin Medical University to examine the sea lion, which is expected to deliver a baby at the end of August. [Photo/Xinhua]