BLM Special Areas

Woodbury Desert Study Area

The Woodbury Desert Study Area (WDSA) was designated by BLM in June, 1977, and includes 3,040 acres. The WDSA is located on a desert bajada in southwest Washington County with numerous washes that run to the south and west into the Beaver Dam Wash. The area is dominated by Joshua trees, creosote bush, and white bursage. The WDSA contains many unique plant and animal species found nowhere else in Utah. The following species are found in or near the WDSA: desert tortoise, desert iguana, desert night lizard, Mohave rattlesnake, speckled rattlesnake, desert kangaroo rat, desert glossy snake, western threadsnake, and Utah blind snake.

From 1930 to 1948, Angus M. Woodbury, and Ross Hardy, with the help of many students from University of Utah, Weber State College, and Dixie State College completed a study on desert tortoises within the WDSA. This study has scientific significance because it contained the oldest population of marked desert tortoises and possibly the oldest marked populations of vertebrates in the United States. During this study, desert tortoises were removed from their winter dens by a person crawling back in the tunnel and removing the desert tortoise. Once removed, they were measured, weighed, and marked with paint or with a brand on their scutes (marginal bones on shell), and then returned to their dens. There were a total of 117 desert tortoises captured and measured during this study.
The Utah Division of Wildlife Resources (UDWR) has constructed several small wildlife guzzlers (rainfall catchments) within the WDSA which provide a permanent source of water for Gambel’s quail and other small animals. Some of these guzzlers were originally constructed in the 1950’s, and were completed through a cooperative agreement between UDWR and the livestock users. Some of these guzzlers have been modified to provide additional water for the expanding herd of desert bighorn sheep in the area.

Once designated, the WDSA was fenced, and signs erected to provide protection to the unique flora, and fauna of the area. In 1998, the St. George Field Office established the Beaver Dam Slope Area of Critical Environmental Concern (ACEC). This ACEC is managed to protect and further the objectives of the Woodbury Desert Study Area, the Joshua Tree National Natural Landmark, and the maintenance of important desert ecosystems that include numerous other plants, and animals listed under state and federal procedures. The ACEC boundaries have been drawn to coincide as much as possible with the boundaries of the same unit in Arizona and Nevada. The entire ACEC links with Desert Wildlife Management Areas, refuges, and other ACECs in the remainder of the desert tortoise Northeastern Mojave Recovery Unit to provide a contiguous recovery zone of more than 1,750 square miles.

UPDATE:   The Woodbury Desert Study Area is now within the Beaver Dam Wash National Conservation Area, which was designated by Congress in 2009.  In 2006, a major wildland fire swept through  a large section of the Beaver Dam Wash National Conservation Area east of Old Highway 91.  Much of the desert vegetation within the WDSA was consumed in the fire.  The ultimate fate of the desert tortoise and other species inhabiting this area remains unclear.

Location Map

    The speckled rattlesnake is found in the Woodbury Desert Study Area.  Photo by Cameron Rognan (copyrighted).





 Single tortoise den in small drainage inside the Woodbury Desert Study Area.





 Desert tortoise just outside its den within the Woodbury Desert Study Area. 





Woodbury Desert Study Area in 2013 after the devastating 2006 fire.