I know a lot do be lamp shy Neil. But you'd be surprised how fast they come to a call at first/last light. I've done it several times over the years here. Just not practical some methods with fields of young lambs. It can be to warm sometimes to drop a terrier, Hounds for me are a no no this time of year. All mine are stock broken but guaranteed fox will head straight through the middle of the young lambs. So daytime calling is an option I use a bit