Pastor maybe it is a depends situation. Put them out and if truly birds just coming into loaf or migrating through should not be an issue. I hunt permanent spread on our rice lease all season and I do fine. Each day just tweak spread for wind, etc. As a trial, if a day or two you have time to pick them up before you have to leave, do it and toss them out the next time you hunt, but just leave them at the spot, cover with some cover/brush. See if results are any better.