I've got 5 chooks in an modest city suburban block. Their run is one metre by 6 metres, which is plenty. They can be kept in less, much less. Their original run was one metre by 3m, and we expanded it when we cleared some more overgrowth in the yard. Every now and then we let them loose on the lawn - they poop everywhere, but the kids have a ball "poop collecting" afterwards,

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They eat just about everything, and go totally nuts over any meat!
If you can give them a run anything over 2sqm, then they'll be fine.
There are a few magazine publications about chook raising that make good reading that can be had from good news agents.
We've had our 5 chooks for over a year now. An average of 4 eggs a day, and chook pooh enriched compost to boot.
The only thing is you need to keep on top of cleaning out their pen, and especially their coup - man they crap a lot, and pest rodents can be attacted to the food scraps. You'll also need to make sure where the coup sits is fox proof. No kidding, the buggers will dig several inches under a fence to get to the birds.
I would have loved to take these birds, but 9 chooks would just be too much for us where I live,

. Not that there would be too many eggs - egg diplomacy works wonders with neighbours and family,

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