Vertebrate Pest Conference: Proceedings
Vertebrate Pest Conference Proceedings: 15th (1992)
Accessibility Remediation
If you are unable to use this item in its current form due to accessibility barriers, you may request remediation through our remediation request form.
Date of this Version
March 1992
Document Type
Article
Abstract
Common ravens (Corvus corax) are a major predator on the threatened desert tortoise (Gopherus [=Xerobates] agassizii). Large numbers of juvenile tortoise shells have been found beneath known raven nests and perches; many shells that show evidence consistent with raven predation have been found sporadically throughout the range of the tortoise; significant proportional decreases in juvenile size/age class distributions have been identified; and people have observed ravens killing, carrying, and consuming juveniles. In 1988 the U. S. Bureau of Land Management initiated a process to evaluate, design, and implement a program to reduce raven predation on desert tortoises. A pilot program was temporarily halted by a law suit filed by the Humane Society of the United States, and a draft long-term plan and Draft Environmental Impact Statement were subsequently issued and are now being modified. Several complex issues have arisen in attempting to design and implement control of ravens including: pitting one native species against another, making management decisions in light of data of varying scientific validity and depth, targeting individuals versus populations, and managing a predation problem over a broad geographic range. Addressing each of the concerns is highly problematic and the solutions are not always satisfying.