Kofa National Wildlife Refuge was established in 1939 and is managed by the U.S. Fish and Wildlife Service. The refuge encompasses 664,327 (1,038 square miles) acres of pristine desert of which some 82% (547,719 acres/856 square miles ) was designated as wilderness with the passage of the 1990 Arizona Desert Wilderness Act. Some 278,400 acres (435 sq mi) of the refuge provide a home for the desert bighorn sheep. The refuge is also home to the California palm, the only native palm in Arizona.
For the purposes of hunt management, Arizona Game and Fish has long divided the state into a series of Game Management Units. In the case of the Kofa NWR, the refuge is divided into three GMUs: Unit 45 A comprises roughly the northwestern third of the refuge, Unit 45B the southeastern third, and Unit 45C the southwestern third. Other surrounding GMUs contain the remaining sections of the greater Kofa Mountains Complex.
In the early part of this century, a number of mines were established in the mountainous areas of the refuge. One of the most notable was the King of Arizona mine. It gave the Kofa Mountains their name-- "Kofa" being contracted from King of Arizona.
Two mountain ranges dominate the landscape--the Kofa Mountains and the Castle Dome Mountains. Although these ranges are not especially high, they are extremely rugged and rise sharply from the surrounding desert plains, providing ideal bighorn sheep country.
Palm Canyon, in the west end of the Kofa Mountains, is well known for its native palms. These palm trees are probably remnants from when this area was wetter and cooler than it is now. Though numbering less than 100, this handful of trees is among the only native palms in Arizona.
The Kofa Mountain barberry (a rare plant found only in southwest Arizona) occurs on the refuge. At the highest elevations in the refuge, oak trees can be found, remnants of more extensive populations from the much wetter conditions that occurred on the refuge millennia ago.
Notable wildlife species found in the area include the white-winged dove, desert tortoise, and desert kit fox. The Refuge has one of the largest desert bighorn sheep populations in the southwestern United States. In recent years, this herd has provided animals for transplanting throughout Arizona and neighboring states.
Birds that are likely to be seen at Kofa include American kestrel, white-winged dove, northern flicker, Say's phoebe, cactus wren, phainopepla, and orange-crowned warbler.