WHOA! Hold on folks. 4 sq ft per bird is bare minimum for interior floor space in a coop intended for night roosting only. It is NOWHERE near enough for birds in general, especially outside, especially long term. 100 birds in an 8 x 12 space is criminal.
DO NOT, I repeat DO NOT, use that as a standard space allowance.
In the old days of Free-Range production, 500 birds per acre was considered maximum. Thats 89 sq.ft./bird, give or take. These birds slept in range shelters, not confined coops. That was considered intense management, as well, and this was rotated between fields to allow the land to rest and "sweeten" between flocks. You can add a few more birds if dealing with Mediterranean breeds or banties, up to about 15% over.
I have an area about 40 x 40 and will only have 10 birds in there. That's 160 sq ft/bird. Experience has taught me that the land can readily absorb their waste with this density and I don't have to lime, or mulch, or shovel s**t, or deal with flies, or diseased, muddy moonscapes when it rains and so on. I can stop being a waste manager this way and actually enjoy my cluckers.
So, keep whatever birds you want, they all lay eggs to one degree or another. But avoid overcrowding at all costs. Less is more.
Here's the rule of thumb for you: If you wonder that you have too many birds for your space... you've answered your own question by using the words "too many" in the first place.
Simply put, the answer is yes.
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I now return you to your previsously scheduled "best egg layer" thread.
