Just the other day I shot a yote at 4:45 in the afternoon. Yesterday my buddy and I called one in about 5:30. My luck has been in the evenings, but I think it depends on the individual pack and area. If the area isn't being hit hard by hunters I would say it really wouldn't matter. If there hungry and they hear you with that squealer, it will be less than 20 minutes before they come running in. Both of mine have been within 15 minutes of my first call. Good Luck