Quail babysitting behavior

I've noticed where I live that two to four quail will guard the young
of several parents. I have counted up to 50+ young being herded by two
or three adults, usually one up on a wall and one or two more on the
ground. I am wondering if other birds also work as collective when
raising the young? I've also noticed the number of young in these
flocks, coveys, or whatever we call them gradually shrink over the
summer until there is slightly less than half what will hatch in late
spring or early summer. By the time the next spring comes not that
many more adults show up. There is already of course a large visible
population of adult quail.

Bob G
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