There are often squirrels as main characters. They are very active and curious, always running around the trees and exploring. Also, rabbits are common, with their cute appearance and sometimes a bit timid nature.
The deer can also be a main character. It is often depicted as the prey, always on the lookout for predators like the wolf or the tiger. Its story is about survival and being vigilant in a dangerous world.
There are probably several main characters in the 'animal picnic story'. For example, the birds are important as they add a lively atmosphere. The bear can also be a main character, being large and noticeable. And of course, the little mice that brought their cheese are also key characters as they contribute to the variety of the picnic food.
Since I don't know the specific 'the last animal stories', it's hard to say exactly. But it could be different animals like a wise old elephant, a clever fox, or a brave little bird.
The main characters could be a group of mischievous monkeys. They are always up to something, like stealing food from other animals or playing pranks on the visitors. Their antics could form the main plot of the story.
It could be a variety of animals. Maybe there are lions as the leaders in some stories, and zebras or antelopes as the ones being protected or following the lead.
Maybe there are some lead animals like an old and wise owl that gives advice about the bridge, and a strong beaver that actually helps build or repair the bridge. There could also be a curious little mouse that discovers the bridge first.
Polar bears are often main characters. They are large and powerful, ruling the Arctic ice. Their hunting for seals and interactions with their cubs are common in these stories.