Conservation in Conflict: the Tale of Two Endangered Species
With its umbrella of provisions, the U.S. Endangered Species Act ( ESA ) provides critical protection to threatened or endangered wildlife. It provides minimal guidance, however, on identifying taxa worthy of conservation, lacks guidelines for resolving endangered species conflicts, and subsequent recovery programs often focus on the species rather than the ecosystem. These deficiencies are exemplified by the recovery program for the San Clemente Loggerhead Shrike ( Lanius ludovicianus mearnsi ) and the recent proposed rule to grant federal protection to one of its predators, the island fox ( Urocyon littoralis ). Recovery actions that have included euthanasia of foxes have likely contributed to a 40–60% decline in the population size of the San Clemente Island fox ( U. l. clementae ), a subspecies listed by the state of California as threatened. The U.S. Fish and Wildlife Service proposes to list four other subspecies of the island fox as endangered but excludes the San Clemente Island fox and the sixth and last subspecies, the San Nicolas Island fox ( U. l. dickeyi ), ignoring their evolutionary distinctness and the recent decline in population size of U. l. clementae. Using published morphological and genetic information, we show that the shrike's current taxonomic and legal status should be reevaluated. We also reexamine the current recovery program for the shrike and conclude that the implementation of the ESA's provisions to protect the shrike was species-centric. The shrike recovery program is primarily centered on two approaches: the release of captive-bred shrikes and control of native and non-native predators. The predator control program has contributed to the endangerment of the distinct San Clemente Island fox. Given that five of the six fox subspecies face extirpation, the proposed rule to list only four of the six as endangered is inadequate. This endangered-species conflict might have been avoided through a more balanced ecosystem approach that considers the ecological role of all native taxa and strives to enhance habitats critical to both the shrike and the fox.
Document Type: Research Article
Affiliations: 1: Department of Fishery and Wildlife Sciences, New Mexico State University, P.O. Box 30003, MSC 4901 Las Cruces, NM 88003-8003, U.S.A., 2: Department of Organismic Biology, Ecology, & Evolution ( OBEE ), University of California, 621 Charles E. Young Drive South, Los Angeles, CA 90095–1606, U.S.A.
Publication date: October 1, 2003