It's a tradition observed throughout most states with upland bird populations-annual predictions based on calls heard along rural postal runs. Between the calls noted by a mail carrier and the birds encountered, wildlife biologists form a framework for the seasons ahead, tallying up the numbers and making the necessary projections. So it is in Iowa this time of year. However, biologists won't need a crystal ball to determine what the pheasant and quail numbers will be. According to Todd Bogenschutz, upland wildlife research biologist for the Iowa Department of Natural Resources (DNR), population counts will be down in almost every county because of a heavy winter mortality, due, in part, to the loss of habitat. Come opening day, hunters may find their favorite species at all-time lows for the past decade. Despite the bad news, northwestern Iowa, especially Emmett County, traditionally has good hunting, even in the lean years, as does the north-central region of the state. Use Highways 7 and 3, both of which run east and west, as a rough dividing line. You'll find birds from 25 to 30 miles south of the blacktop up to the Minnesota border. Contact: Iowa DNR, Wildlife Bureau (515-281-5918).