Couldn't You create a snake-free area by a snake-fence?
http://www.snake-removal.com/fencing.html
http://snakefence.net/products/snake-barrier/
http://www.boddingtonsonline.com/product...arden-fence.php

With this fence, it could be possible to reduce additionally the mouse invasion and protect the chicks (if the poultry fence has bigger mesh size) against cats, other four feet predator and snakes. I would prefer the Boddington fence, as it is more stable and probably longer persistent as the real snake fence - If You don't prefer the traditional solution with stainless steel wire mesh with similar mesh size?
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