So the first image is, obviously, from YKA but the second one is an emblem of polish 22nd Transport Company that existed during the II World War.
Why bear? Because Poland has a bear-soldier. Really. His name was Wojtek and he was corporal.
So the story begins in 1942. Polish soldiers of Anders Army* were wandering through Iran. A young, local boy has showed them a baby bear whose mother had been killed and the soldiers decided to keep the animal. They called him Wojtek (meaning of the name - "person who enjoys the war") and took care of him.
They fed him with things suitable for bear like honey or fruits but also with beer and cigarettes. Not on daily basis - only as a reward.
What's interesting, Wojtek was able to smoke cigarettes but he preferred to eat them.
The soldiers have even managed to teach him how to salute.
He liked a company and sometimes slept with soldiers (and hugged them).
And the army was wandering through Iraq, Syria and finally Egypt. But in Egypt soldiers had faced a huge problem - no one wanted to allow to transport a bear in ship from Egypt to Italy. But soldiers simply made Wojtek a soldier in rank of corporal so he could stay with them.
He was grown-up bear then so soldiers decided to make him carry ammunition and due to the reports he was doing his job very well.
After the war he spent some time in Switzerland but in 1947 he was moved to the Zoo in Edinburgh.
Soldiers were not satisfied because they wanted to keep him forever but they were trying to pay him a visits frequently.
Wojtek died in 1963.

*army was created by Soviet Union and consisted of Poles who were forced to live in the East