Are shrimp social like schooling/shoaling fish?

I've got a few stray feeder shrimp (maybe they are ghost shrimp?) in my tanks, and I believe that there is only one in my 55.
Is he ok by himself? Or do shrimp need the company of their own species like some fish?

Well, as luck would have it, I found a female with eggs in my 20, so I caught her and moved her to the 55. Maybe this will start up a colony in there. Although, I hope I still have at least one female left in the 20. They're good hiders I rarely see more than one at a time, although I once saw at least three together, which is what makes me think the 20 has a decent colony going.

I only have bettas, one in the 55 and another in the 20.
I think the betta in the 55 pretty much ignores the shrimp, so I'm hoping a few babies will grow up and start breeding.
Oh, and I found another berried female in the 20, so it looks like both tanks now have at least one berried female each.