From what I’ve personally seen NEAR my property….there is no training.
A ferret will naturally smell the existence of rabbits, and immediately go down the rabbit hole to investigate. The rabbits, then are afraid, and quickly escape from another hole.
Hunters know that the distance between holes is usually 4 or 5 meters, and stand prepared to blast the first bigger animal to leave that distant hole.

The ferret comes happily out of the hole a minute later.

This make rabbit hunting so easy, that it is illegal here in Belgium. But people still do it. Usually the richer people who own the land, and consider it their right to break the laws.
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