During a patrol on Lake Kenon, rescuers discovered a poor dog lying in the cold weather, legs and tail stuck under an ice hole. In countries near the North Pole, the cold climate causes rivers to freeze all year round. Ice forms a thin layer on the surface of the lake, preventing cold air from continuing to spread down, freezing all the water in the lake. Although the water under the ice is still very cold (about 4 degrees Celsius), there are still many fish species here. These cold-blooded animals have the ability to change their body temperature to adapt to the harsh climate here.