the birds i hunt tend to have two different season patterns...spring/summer and fall/winter...it might not vary too far from each other...but i do know on one farm i hunt they travel from one end of the property in their transition to the other....where they were this past fall and late winter (forage and survive)....they wont be this spring and summer (breed and hatch eggs)..not sure why?!..my guess is your seeing that transition.