Non-violence is the greatest Dharma; So too is all righteous violence.
No life without Sun
Coming to the question raised here. All creatures either try and escape or put up a fight when their life is in danger. Since the bear finds itself trapped my guess is that it will try and defend itself. Here is what the bear will probably do –
1. Turn around and face its predator
2. Stand on its hind legs to appear more menacing
3. Bare its fangs and claws in an attempt to threaten
4. Make angry sounds to intimidate its attacker
5. Charge towards its attacker and battle it out
The chances of its predator being smaller than the bear are high. How many predators are there in the wild that actually attack bears? My guess is that the bear will overcome its fear and take on its predator and defeat it.
"A love affair with knowledge will never end in heartbreak" - Michael Garrett Marino
https://www.youtube.com/watch?v=o5SgYAVaIpQ ( watch this video this is really wonderful video )
But leaving that possibility I think the bear is trying to find something in tree shell ( may be honey or something to eat) and suddenly realized some animal is behind it and so it is just checking .
"It is hardest thing in the world to be good thinker without being a good self examiner"
But I honestly don't believe that there'd be an animal courageous enough to chase a bear. If it is another bear, then not even swimming away would help. Because both of them are adept at swimming. And fighting in water is difficult and exhausting. So I think the bear might just leap onto it's enemy with all the courage it can muster.
The stronger a light shines the darker are the shadows around it.
If enemy is powerful, bear has not much choices either he has to jump down in the marsh or water and try to swim away or wait on the tree trunk till night and try to take advantage of dark in confronting the enemy.
In any case waiting may sometimes resolve the crisis as other animals may be passing through and that may distract the enemy to easier preys and bear may be forgotten.
Knowledge is power.
Another situation which can be imagined is. the bear is on the tree. The enemy is waiting near down there. Meanwhile another animal slowly coming towards that place. This has been noticed by the enemy and the enemy started chasing the animal coming that way forgetting about the bear. It has gone long way. Bear is relaxed now, came down happily and gone back to its place.
'Idhuvum Kadandhu Pogum "
Even this challenging situation would ease