Rather than humidity it might be that frequnet rains in late spring with sparse nesting habitat combine to produce very few offspring. NE is quite humid in the late spring and early summer, our pheasant numbers tend to go way up in dry years and down in very wet years. Our wild pheasant numbers are very dependent on having good or bad nesting conditions in June & July. We are in the 5th year of drought and the pheasant numbers are better here than they have been in a long time. \:\)