Pretty much all the Watchers we've seen appear with masculine caharacteristics (bald heads, beards, general facial structure, wide shoulders and thin hips)
Now, are we to assume that there are female Watchers out there and we just don't see them?
then again, it has been said on some occaasions that Watchers aren't really corporeal beings, so gender would be entirely arbitrary, but I'd still ask why they take the forms of male humans
than again, I don't think anything with hips wide enough to pass those heads would be able to walk...
are there "female" Watchers?