Chinese scientists onboard the Snow Dragon icebreaker, which is travelling through Arctic waters, have been treated to a rare sight of a polar bear in its natural habitat.

The polar bear seen by the Chinese scientists is said to be a male bear in its prime, around two meters in length and weighing at least four hundred kilograms. In what appears to be a sign curiosity to those onboard, the bear lingered beneath the vessel for a good thirty minutes, strolling on floated ice and occasionally laying down for a rest. But the scientists say the encounter might have been much less pleasant if they were on ice with the bear, as polar bears are known to be very territorial.

This is China’s sixth Arctic expedition, aimed at researching environmental changes in polar regions, which is endangering many species, including polar bears.