Once Childermass has settled down into whatever place the carnival has fortified (assuming that hedge fort did happen?), he'll be sending his shadow birds out as surveillance. He's been asked to keep an eye out for two specific things:

A. The Ringmaster, since she's been noted as MIA and B. If the hunters are originating from around one point in particular (a certain location, a certain being, etc) or if they're just flooding in with no real way of telling from where or how.