The major reason I'd consider getting guineas would be to get rid of ticks. Do they really do that?? how many would I need for a 3 acre property.
That's why I originally got Guineas, and altho it was not instantaneous, mission accomplished! So YES they are effective tick control, but to maintain the perk of their tick controlling abilities, it takes some serious work on your part to maintain a flock of Guineas. For 3 acres... I would keep no less than 6, but more (like 10-12) would be more effective and you'd have a much happier flock.
I have chickens, and they would have to share the same coop.
I'm not gonna sugar coat this one, and I am not out to be offensive to you or anyone with this answer, so please don't take it that way, but... Unless it's a really large coop and covered run set-up, everybody gets plenty of free range time, AND you have a plan B at the ready (aka a separate place to put the Guineas)
if it doesn't work out... it might not be a good idea (for all those involved... Guineas, chickens and YOU). A lot of new, inexperienced Guinea owners that try to integrate Guineas with their flock of chickens fail at it, either right away or come the following spring/breeding season. Not all breeds of chickens can deal with Guineas and "Guinea energy" (aka Guinea aggression). Many have no problems at all, many have nothing but problems, it all depends on the set up, the temperament of all birds involved, and your poultry routine and experience (plus a few other contributing factors... like patience and tolerance, lol). There's plenty of pros and cons about co-mingled flocks to read about on this forum (and elsewhere), so grab a comfy chair, a cup of coffee and read EVERYTHING you can find about that topic. Guineas are not at all like chickens (other than they all have feathers and beaks, they all roost when they sleep and they can all eat a variety of the basically the same feeds once they mature) and IMO they shouldn't be raised or treated as such. Guineas need 4 sq ft of floor space in the coop PER BIRD, twice that in a covered run for the days they can't be let out to free range, (this is mainly JMO tho, because it is what works for me and has worked for me for years. Overcrowding ALWAYS results in aggression where Guineas are concerned). Guineas are not for everyone, so I'd do
a lot of homework on them if I were you prior to buying any. And I do not say that lightly.
When I was growing up we had guineas, so I know they're funny, but they are also noisy, want to sleep outside on the trees etc. So... are they worth the trouble?
If you want effective, chemical free, natural tick control and you have the set-up, time, energy and patience for dealing with Guineas and all their personality and behavioral quirks... then yes. Again, this is JMO, I am sure you will get a variety of answers to these questions, lol.
And if so, should I get only males ( I hear they're less noisy) ?
Both the males and females tend to scream bloody murder CHI-CHI-CHI-CHI-CHI-CHI-CHI at
anything that startles them or even looks sideways at them, but the females pretty much constantly buck-wheat all day long (and sometimes all night) and all year long, lol. They settle down some as they mature, but let me really emphasize the word
some.
Good luck with your reading...