THE SUPERIOR VALLEY TORTOISES
The Southwestern Expansion of Fort Irwin Will Accelerate Loss of the Imperiled Desert Tortoise from the Western Mojave Desert
- In January 2000, a blue ribbon panel of 12 scientists convened to determine conservation measures to offset the Fort Irwin expansion concluded that the status of the desert tortoise had deteriorated so much that the tortoise population in the West Mojave Recovery Unit is more appropriately characterized as "endangered" than "threatened" even if Fort Irwin does not expand.
- New field studies show that the desert tortoise population in California's western Mojave Desert is still undergoing a massive decline. The March/April 2001 USGS survey of the Fremont Valley permanent study plot has found 50% less live tortoises and 50% more dead than in 1996.
- The Army's own surveys completed in 1998 and 1999, show that the expansion areas support some of the highest numbers of desert tortoises remaining in the West Mojave Desert.
- The tortoise would lose over 87,000 acres (136 square miles) of designated critical habitat under the proposed expansion. As many as 15% of the West Mojave tortoises would be taken. The tortoises and their critical habitat on the Naval Air Weapons Station will be effectively isolated from tortoise to the south.
The Key Elements document drafted for Congress by the Secretaries of the Army and Interior states that the 21,000 acres in the south that are currently set aside on the NTC will return to training use. The thriving tortoise population in the UTM 90 area at the south end of the base will be lost.