Japanese Cranes, also known as Tancho ('red head' in Japanese), were thought to have gone extinct due to overhunting and farming expansion. However, in the beginning of the 20th century a group of about 20 birds was discovered in the marshes of Kushiro. Since then their number grew to over 1,000 thanks to the conservation efforts. Now the Kushiro Marshland attracts hundreds of photographers and birdwatchers.
It's best to watch cranes when they perform their pair dance, surprisingly choreographed and synchronised. The cranes usually gather around winter feeding sites easily accessible either by car or by public transportation. Feeding takes place once or twice a day, depending on the station.
One of the best spots to go to is the Tancho Observation Center where besides an observation point you can find other facilities such as restroom and a restaurant. Another spot you can choose is Tsurumidai feeding ground.
The area doesn't receive much snowfall even in winter months, but hopefully you are lucky to spot the cranes with the snowy background!