If you want to find out where your rats are coming from go outside at night with a black light, (the kind that were popular during 70's), and the trails of their urine will show up under it. You can then mount an attack to block out where they get in, or trace where they may be spending most their time. If it is away from your chickens you can set up other traps there or along the path - they use the urine to mark off for others to follow.

One farmer suggested using a deep bucket, one they can't climb out of or knock over. Fill it full of water at night and place an apple in it - they jump for the bobbing apple and they drown. He says he catches 10 or 12 a night sometimes using this. Cheers from Canada, Nancy

~~ For further information ~~ : There is a report on the humane control of rodents on the Universities Federation for Animals Welfare (UFAW) website here :
http://www.ufaw.org.uk/documents/GuidanceonhumanecontrolofrodentsFeb2509V19.pdf
The information is UK-based but may still be of interest to those outside of the UK as well.

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