[Pigtails]

Saw two last evening on my croft, I hae domestic fowl, should I be worried?

[HappyHippy]

If there's plenty of other alternative food for them they might not bother with your chickens, but I dare say if food was scarce they might have a go at them.
If the chickens are a new introduction and this is the first time you've seen the polecats they might be checking them out.
Others will know better than me, but I'd just keep a close eye on things and wait and see what happens.