The Cranes and the Serpent
Once in a fig tree on the bank of the river Airavati some cranes had built their nests. A serpent living in a hole under the tree used to feed on the eggs and the young ones of the cranes.

In distress the cranes sought the advice of an elderly crane. The old crane told them a plan. "At a little distance from here is a burrow of a mongoose and its family. Catch plenty of fish and lay a trail from the hole of the serpent to the burrow. It will lead the mongoose to the serpent and being natural enemies will kill the serpent and thus you will be rid of it".

The cranes did as they were told. The smell of the fish brought the mongoose out from its burrow till it reached the snake's hole. Then a fierce fight ensued and at last the serpent was killed. The cranes were delighted that their plan was a success. But suddenly to their dismay they noticed that the mongoose was attracted by the cries of the young birds. It climbed up and feasted on the young birds. The cranes had got rid of one enemy only to invite another. They had entirely forgotten that the mongoose was the enemy of not only serpents but also of cranes. It is truly said that one should not place any confidence in one's enemies.
The Cranes and the Serpent