Wintertime in Iowa means that your light conditions are constantly changing. There have been times where I have seen the weather change from cloudy to sunny and back in a matter of minutes. There are also many days that are overcast, and it is hard to draw out the details in your photography subjects.
Elements on the landscape can also cause shadows that ruin a picture. It is not uncommon to delete multiple shots of a creature that was in poor lighting. By paying attention to the lighting conditions, I could have saved my shots for when they were in a better position. Waiting for your subject to move a couple of inches or across the clearing can make a world of difference in your final image.
Be patient, watch your lighting, and you will find that you have fewer photos to delete when you get around to editing.