People view living corals in the aquarium's laboratory during the World Oceans Day event at Vancouver Aquarium in Vancouver, Canada, June 8, 2019. Thousands of people visited Vancouver Aquarium and participated in different aquatic-themed activities to mark the World Oceans Day. (Xinhua/Liang Sen)

People take closer look at marine animals during the behind the scene tour of the aquarium's laboratory during the World Oceans Day event at Vancouver Aquarium in Vancouver, Canada, June 8, 2019. Thousands of people visited Vancouver Aquarium and participated in different aquatic-themed activities to mark the World Oceans Day. (Xinhua/Liang Sen)

A girl tries to feel the surface of a sea star in the aquarium's laboratory during the World Oceans Day event at Vancouver Aquarium in Vancouver, Canada, June 8, 2019. Thousands of people visited Vancouver Aquarium and participated in different aquatic-themed activities to mark the World Oceans Day. (Xinhua/Liang Sen)

A visitor views a tank displaying the plastic waste which is hazardous to the ocean during the World Oceans Day event at Vancouver Aquarium in Vancouver, Canada, June 8, 2019. Thousands of people visited Vancouver Aquarium and participated in different aquatic-themed activities to mark the World Oceans Day. (Xinhua/Liang Sen)

Children learn about different types of bones from the ocean mammals during the World Oceans Day event at Vancouver Aquarium in Vancouver, Canada, June 8, 2019. Thousands of people visited Vancouver Aquarium and participated in different aquatic-themed activities to mark the World Oceans Day. (Xinhua/Liang Sen)

People view ocean garbages displayed during the World Oceans Day event at Vancouver Aquarium in Vancouver, Canada, June 8, 2019. Thousands of people visited Vancouver Aquarium and participated in different aquatic-themed activities to mark the World Oceans Day. (Xinhua/Liang Sen)

People view water creatures in the aquarium's laboratory during the World Oceans Day event at Vancouver Aquarium in Vancouver, Canada, June 8, 2019. Thousands of people visited Vancouver Aquarium and participated in different aquatic-themed activities to mark the World Oceans Day. (Xinhua/Liang Sen)

People participate in the behind the scene tour of the aquarium's laboratory during the World Oceans Day event at Vancouver Aquarium in Vancouver, Canada, June 8, 2019. Thousands of people visited Vancouver Aquarium and participated in different aquatic-themed activities to mark the World Oceans Day. (Xinhua/Liang Sen)