I've only called in a couple of bears, and actually that isn't true- I didn't call them in, the electronic caller did. But with these two incidents, the bears came in both times right at a full hour of calling. At least that is when we first saw them. I have no idea how long they had been responding to the call or how far they came to get there. So I would say to try to give it at least an hour. I don't know if the time of day is significant but both bears came in somewhere around 10 to 11 in the morning.