Ocean Park reported yesterday that two of their recently imported rare Chinese sturgeons (Acipenser sinensis) died at the park yesterday.

The sturgeons were imported from the mainland China on February 18th with 13 other fish. The two sturgeons were found to be swimming abnormally on April 21st. By May 11th they were given immediate support but still died shortly after.

Ocean Park found one sturgeon died of a gill infection and the other had infections in several internal organs.

Wild Chinese sturgeons are critically endangered and protected species that have existed for a 140 million years. Most sturgeon are anadromous meaning they spawn in fresh water and migrate to salt water to mature. Historically this fish was found in China, Japan and the Korean Peninsula, but it has been extirpated from most regions due to habitat loss and overfishing. They dwell along the coasts of China’s eastern areas and migrate back up rivers to reproduce when they reach sexual maturity. Although females carry in excess of a million eggs in one pregnancy, the Chinese sturgeon’s reproductive capacity is poor because it only breeds three or four times during its life and the survival rate to hatching is estimated to be less than 1 percent.