I have a small colony in a poly nuc that requires a small boost of workers to really get it going before autumn. They're already stretched across the current brood frames so I don't want to just add a frame of capped brood as its likely to chill. Does anyone have any good methods for introducing workers straight into a hive? Or am I just going to be starting all out warfare? The nuc is away from the main apiary so returning workers wouldn't be an issue.