In October 1977, Southern California Edison and Arizona Public Service issued a five year contract to Dr. E. Linwood Smith and Associates of Tucson, Arizona, to study potential impacts of a proposed 500 kV transmission line on desert bighorn sheep. The study is divided into three phases: 1) preconstruction baseline data acquisition, 2) construction-impact monitoring, and 3) post-construction impact evaluation. The proposed line will transmit power from the Palo Verde Nuclear Power Plant, approximately 30 miles west of Phoenix, Arizona, to Edison's Devers Substation near Palm Springs, California. The line will traverse bighorn habitat in the Plomosa and Dome Rock Mountains of western Arizona. In November 1977, 20 bighorn were captured and fitted with radio telemetry collars. Seventy percent of the collars on rams failed during the first year. Thus, in November 1978, in an attempt to replace nonfunctioning collars and to increase the study population, 18 bighorn were captured, three of which were originally collared in 1977. A total of 38 captures have been made; effective December 1978, 26 sheep had functioning radio-transmitting collars. Radio telemetry flights were flown every five days to monitor movement of collared sheep. During the first 12 months of study, over 1100 relocations were made. This paper is designed to serve as an introduction to the study. Data on capture activities and preliminary trends resulting from telemetry monitoring are presented.
|
