There are more carnivore animals than just snakes.
You still don't understand.
They disembarked from the ark about precisely one year later.
A flood like it say in the bible would also destroy the land. A lot of the natural habitat would be gone, and would need more than just a few day.
For the humans:
- Water would be undrinkable for months.
- They can't eat the animals that they have because they have to allow the animals to repopulate the earth, and that would take a lot while.
- They can't begin farming immediately, and even if they did, it would take a whole season or 2 to grow them before harvest.
For the animals:
- What would the animals eat at the meantime, while the other animals repopulate the earth or for the plants to grow?
- What would they drink?
If they release the wild animals, the carnivore would eat herbivorous animals. The herbivorous animals would starve while they wait for the right plants to grow. And if much of the lands have indeed being under water for so long, then you can't pick fruits from bushes and trees, because these plants would have rotted.
Humans would starve too, because they can't the animals they have, and they can't eat anything they could farm, because it would take time to grow.
You are forgetting that the bible say they landed on Mt Ararat.