Essential pronghorn habitat is that habitat that ODFW district biologists determined to be necessary to maintain current pronghorn populations. It is not all the occupied pronghorn habitat in Oregon but loss of this habitat would result in the declne of pronghorn herds. All these habitats are considered essential although they have different types. The types include essential and important summer range; essential and important winter range; essential and important transitional habitats or migration corridors; high concentration areas; fawning habitat; migration/transition range, and a combinations of multiple types. The mapping is based on existing Goal 5 mapping, expert knowledge of field staff, collar data, herd composition surveys, and other aerial surveys.