DOCSLIB.ORG

California Department of Fish and Wildlife Peninsular Bighorn Sheep Annual Report 2015

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
California Department of Fish and Wildlife Peninsular Bighorn Sheep Annual Report 2015 CALIFORNIA DEPARTMENT OF FISH AND WILDLIFE PENINSULAR BIGHORN SHEEP 2015 ANNUAL REPORT A cooperative effort by the California Department of Fish and Wildlife, U.S. Fish and Wildlife Service, and California Department of Parks and Recreation Photo by Janene Colby This report presents information on the status, distribution, and management of peninsular bighorn sheep in eastern San Diego County and portions of Riverside and Imperial Counties for 2015 Authors Janene Colby and Randy Botta South Coast Region California Department of Fish and Wildlife Peninsular Bighorn Sheep Annual Report 2015 Table of Contents Executive Summary………………………………………………...1 Background……………………………………………………….......3 Capture and Radio-collaring……………………………………3 Radio Collar Status………………………………………………….4 Population Size and Estimation…………………….………..5 Respiratory Disease………………………………………………..5 Cause Specific Mortality and Survival……………………..6 Lamb Survival and Recruitment……………………………...8 Distribution and Movement………………………………….11 San Jacinto Mountains………………………………………...12 Central Santa Rosa Mountains………………………........12 Southern Santa Rosa Mountains……………………….....15 Vallecito Mountains………………………………………......16 Threats to Recovery………………………………………….….17 San Jacinto Mountains…………………………................17 Northern Santa Rosa Mountains………………………….17 Central Santa Rosa Mountains………………….……...…17 Southern Santa Rosa Mountains…………………….……19 Coyote Canyon…………………………………………….….…19 Northern San Ysidro Mountains………………….….…...19 Southern San Ysidro Mountains……………………..…...20 Vallecito Mountains……………………………………………20 Carrizo Canyon……………………………………………..…...21 Future Actions……………………………………………………...22 Citations……………………………………………………………....23 California Department of Fish and Wildlife South Coast Region 3883 Ruffin Road San Diego, CA. 92123 www.wildlife.ca.gov Photo by Jeff Young EXECUTIVE SUMMARY Desert bighorn sheep (Ovis canadensis nelsoni) inhabit the desert slopes of the Peninsular Ranges of southern California and extend into the mountains of Baja California in Mexico. The population within the Peninsular Ranges was first listed as threatened in 1971 under the California Endangered Species Act. In 1974, the population was estimated at 1,171 (Weaver 1975) but by 1996 the rangewide population estimate had declined to only 276 adult sheep (USFWS 2000). Peninsular bighorn sheep were listed as a federally endangered population segment in 1998 (63 FR 13134) due to: 1) habitat fragmentation, degradation, and loss by urban and commercial development; 2) disease; 3) predation coinciding with low population numbers; 4) response to human disturbance; 5) insufficient lamb recruitment; 6) nonnative toxic plants; and 7) prolonged drought (USFWS 2000). Presently, the population of desert bighorn sheep in the Peninsular Ranges is considered to be stable to increasing based on the most recent 2010 California Department of Fish and Wildlife (CDFW) rangewide survey estimate of 955 bighorn sheep. In order for CDFW to estimate ewe (female) abundance it is necessary to maintain radio-collars on at least 25% of the ewes within each of the 9 recovery regions within the Peninsular Ranges. At the beginning of 2015, there were a total of 94 active radio-collars throughout the Peninsular Ranges (89 ewes & 5 rams). This represented only 16% of the ewe population rangewide. During the fall 2015 capture an additional 91 active radio-collars (84 ewes & 7 rams) were deployed in the San Jacinto Mountains (SJM), Northern (NSRM), Central (CSRM) and Southern (SSRM) Santa Rosa Mountains, Coyote Canyon (CoC), Northern (NSYM) and Southern (SSYM) San Ysidro Mountains, and Vallecito Mountains (VM) recovery regions. In 2015, there were 13 radio- collared sheep mortalities (11 ewes and 2 rams). Mortalities by recovery region were: NSRM = 1 ewe, CSRM = 1 ewe, CoC = 2 ewes, SSYM = 1 ewe, VM = 2 ewes, and Carrizo Canyon (CC) = 4 ewes & 2 rams. At the close of 2015, 29% of the ewe population was radio-collared with a total of 171 active radio-collars throughout the Peninsular Ranges (161 ewes & 10 rams). A field-based capture is tentatively planned for October 2016 to fill any remaining radio-collared gaps prior to the rangewide population survey in November 2016. From 1992 to 2016, on average, 12% of all active radio-collared sheep died each year of which 7% was due to predation. In 2015, only 7% of all active radio-collared sheep died of which 3.2% were due to predation, 2.2% California Department of Fish and Wildlife Annual Report 2015 Page 1 the cause was unknown, and 1.6% was attributed to nonpredation. The average age of radio-collared ewes in 2015 was 7.1 years with a range between 1.5 and 19 years (n = 173). In comparison, the average age of radio- collared ewes that died was 12.0 years with a range between 8 and 16 years (n = 11). In 2015, average rangewide survival of radio-collared ewes was 87%. Over the past 5 years (2011 – 2015), average survival of radio-collared ewes from highest to lowest was SJM (100%), followed by VM (98%), NSRM (93%), NSYM (91%), CC (91%), CSRM (88%), CoC (86%), and SSYM (80%). Survival statistics were not available for the SSRM due to lack of radio-collared sheep. CDFW has monitored lamb survival (survival to 3 months) and recruitment (survival to 1 year = yearlings) within 2 to 5 recovery regions from 2008 to 2015. The percentage of 2015 lambs that were recruited to yearlings was lowest in CoC (10%), followed by the NSYM (11%), the “urban” ewe group in CSRM (11%), the “wild” ewe group in CSRM (33%), and the IKP ewe group in CC (35%) recovery regions. Typically, lamb survival levels below 30% indicate the presence of lamb respiratory disease within a ewe group. Clinical signs of lamb pneumonia have been documented in all 5 recovery regions; however, rates of lamb survival and recruitment have varied by ewe group, season, and year. For the past 8 years, the average recruitment ratio has been very low (18%) in both CoC and NSYM. Presently, there is substantial genetic variation and gene flow among bighorn sheep populations within the Peninsular Ranges and across the US-Mexico Border indicating functional connectivity (Buchalski et al. 2015). However, as traffic levels continue to increase connectivity will be lost. The most frequent reports of sheep being killed while attempting to cross roads are on Highways 74 and 78, Interstate 8, and County Roads S22 and S3. Other concerns that may hinder recovery efforts are: disease, the loss of natural water sources, reduction and fragmentation of sheep habitat, habitat modification due to invasive nonnative plants, sheep use of urban areas, and human disturbance of essential sheep habitat especially around the urban centers. Yet, even in more remote regions renewable energy projects, completion of the US-Mexico border fence, mining, and human activities (border enforcement and off-road vehicles) may alter, discourage, or restrict sheep movement and habitat use of important resources. Hopefully, continued efforts by CDFW to monitor sheep health, habitat use, and movements throughout the range will provide federal, state, and local governmental agencies and city planners information to make land and public use decisions that allow for the health and long-term survival of peninsular bighorn sheep. Photo by Jeff Young California Department of Fish and Wildlife Annual Report 2015 Page 2 BACKGROUND This annual report highlights capture and radio- Peninsular Bighorn Sheep collaring, radio-collar monitoring, disease Map 1 Recovery Regions surveillance, cause specific mortality investigation, 3,208 km2 1 – San Jacinto Mountains – 168 km2 and lamb survival monitoring undertaken by the 2 – N. Santa Rosa Mountains – 194 km2 1 3 – C. Santa Rosa Mountains – 257 km2 California Department of Fish and Wildlife (CDFW) 10 4 – S. Santa Rosa Mountains – 562 km2 5 – Coyote Canyon – 250 km2 of bighorn sheep in the Peninsular Mountain 6 – N. San Ysidro Mountains – 86 km2 Ranges of southern California from 1 January 2015 7 – S. San Ysidro Mountains – 117 km2 8 – Vallecito Mountains – 708 km2 through 31 December 2015. 2 9 – Carrizo Canyon – 866 km2 Riverside 74 USFWS Critical Habitat The Peninsular Mountain Ranges contain 9 3 Anza-Borrego Desert State Park designated bighorn sheep recovery regions City Centers occupying portions of western Riverside, western Wind Farm Infrastructure Imperial and eastern San Diego Counties (Map 1). County Boundary The 9 recovery regions are: 1) San Jacinto 5 4 Mountains (SJM); 2) Northern Santa Rosa Mountains (NSRM); 3) Central Santa Rosa Salton Sea Mountains (CSRM); 4) Southern Santa Rosa 6 86 Mountains (SSRM); 5) Coyote Canyon (CoC); 6) San Diego Northern San Ysidro Mountains (NSYM); 7) 7 Imperial Southern San Ysidro Mountains (SSYM); 8) 78 Vallecito Mountains (VM); and 9) Carrizo Canyon (CC). 8 A Cessna 185 fixed-wing aircraft was used to conduct aerial telemetry monitoring at least once a month in all 9 recovery regions. Telemetry flights, however, were not conducted for the first 3 9 months of 2015 following the retirement of 8 CDFW’s southern California Air Services pilot in December 2014. Telemetry flights were recommenced in April 2015 when the vacant pilot position was filled. Flights were used to monitor radio-collared sheep status (alive/dead), obtain location estimates, and download GPS location data. CDFW conducted ground telemetry monitoring of radio-collared sheep twice a month in all recovery regions except for the SJM and NSRM which were monitored by the Bighorn Institute (BI). Satellite-collared sheep in the SJM, CSRM, SSRM, and VM were monitored
Load more

Recommended publications
  • Geology of Hawk Canyon, Anza-Borrego Desert State Park, California
    GEOLOGY OF HAWK CANYON, ANZA-BORREGO DESERT STATE PARK, CALIFORNIA By Jeffrey D. Pepin Geological Sciences Department California State Polytechnic University Pomona, California 2011 Senior Thesis Submitted in partial fulfillment of the requirements for the Bachelor of Science Geology Degree Table of Contents Abstract ...............................................................................................................................1 Introduction ........................................................................................................................2 Purpose and Objectives ....................................................................................................2 Regional Geology .............................................................................................................4 Field Site Description .......................................................................................................9 Discussion of Previous Work Done in Hawk Canyon ...................................................11 Observational Data ..........................................................................................................12 Field Techniques ............................................................................................................12 Global Positioning System (GPS) Data and Notes ........................................................14 Orientation Data by Structure ........................................................................................20 Lithology ........................................................................................................................21
    [Show full text]
  • Right-Sljp Offset of the Eocene Ballena River Valley Across the Elsinore Fault Zone, Southern California
    http://dx.doi.org/10.7773/cm.v9i1.412 RIGHT-SLJP OFFSET OF THE EOCENE BALLENA RIVER VALLEY ACROSS THE ELSINORE FAULT ZONE, SOUTHERN CALIFORNIA Patrick L. Abbott Ronald P. Kies Dermis R. Kerr Department of GeologicaI Sciences San Diego State University San Diego, California 92182 U. S. A. ABSTRACT TWO small paleovalleys carved into granitic rocks of the Peninsular Ranges contain conglomerates similar to the Eocene Ballena Gravels farther west in San Diego County. These conglomerates are dominated by the distinctive, temporally restricted, Poway rhyolite clasts. The newly discovered fluvial conglomerates lie in the Vallecito Mountains east of the Elsinore fault zone. Extrapolation of the offset fluvial valley trends to the Elsinore fault suggests 37 kilometers (23 miles) of right slip. RESUMEN Dos valles pequeños paleolíticos, grabados en cuerpos graníticos de la Cor- dillera Peninsular, contienen conglomerados semejantes a las gravas de la Forma- ción Ballena del Eoceno, localizada al peste, en el Condado de San Diego. Este conglomerado es dominado por clastos riolíticos de la Formación Poway, los cuales son característicos y están temporalmente restringidos. Los conglomerados fluviales recientemente descubiertos, se encuentran en las Montanas del Vallecito, al este de la zona de la falla de Elsinore. Proyectando los rumbos de los conglome- rados fluviales y de las gravas a través de la falla de Elsinore, se observa un despla- zamiento de 37 km. (23 millas) en un sentido lateral-derecho. INTRODUCTION The Ballena Gravels (actually conglomerate ) were named by Fairbanks (1893) for a prominent, southwest-trending line of outcrops on the western flank of the batholithic Peninsular Ranges in San Diego County (figure 1).
    [Show full text]
  • Anza-Borrego Desert State Park Bibliography Compiled and Edited by Jim Dice
    Steele/Burnand Anza-Borrego Desert Research Center University of California, Irvine UCI – NATURE and UC Natural Reserve System California State Parks – Colorado Desert District Anza-Borrego Desert State Park & Anza-Borrego Foundation Anza-Borrego Desert State Park Bibliography Compiled and Edited by Jim Dice (revised 1/31/2019) A gaggle of geneticists in Borrego Palm Canyon – 1975. (L-R, Dr. Theodosius Dobzhansky, Dr. Steve Bryant, Dr. Richard Lewontin, Dr. Steve Jones, Dr. TimEDITOR’S Prout. Photo NOTE by Dr. John Moore, courtesy of Steve Jones) Editor’s Note The publications cited in this volume specifically mention and/or discuss Anza-Borrego Desert State Park, locations and/or features known to occur within the present-day boundaries of Anza-Borrego Desert State Park, biological, geological, paleontological or anthropological specimens collected from localities within the present-day boundaries of Anza-Borrego Desert State Park, or events that have occurred within those same boundaries. This compendium is not now, nor will it ever be complete (barring, of course, the end of the Earth or the Park). Many, many people have helped to corral the references contained herein (see below). Any errors of omission and comission are the fault of the editor – who would be grateful to have such errors and omissions pointed out! [[email protected]] ACKNOWLEDGEMENTS As mentioned above, many many people have contributed to building this database of knowledge about Anza-Borrego Desert State Park. A quantum leap was taken somewhere in 2016-17 when Kevin Browne introduced me to Google Scholar – and we were off to the races. Elaine Tulving deserves a special mention for her assistance in dealing with formatting issues, keeping printers working, filing hard copies, ignoring occasional foul language – occasionally falling prey to it herself, and occasionally livening things up with an exclamation of “oh come on now, you just made that word up!” Bob Theriault assisted in many ways and now has a lifetime job, if he wants it, entering these references into Zotero.
    [Show full text]
  • Southern Exposures
    Searching for the Pliocene: Southern Exposures Robert E. Reynolds, editor California State University Desert Studies Center The 2012 Desert Research Symposium April 2012 Table of contents Searching for the Pliocene: Field trip guide to the southern exposures Field trip day 1 ���������������������������������������������������������������������������������������������������������������������������������������������� 5 Robert E. Reynolds, editor Field trip day 2 �������������������������������������������������������������������������������������������������������������������������������������������� 19 George T. Jefferson, David Lynch, L. K. Murray, and R. E. Reynolds Basin thickness variations at the junction of the Eastern California Shear Zone and the San Bernardino Mountains, California: how thick could the Pliocene section be? ��������������������������������������������������������������� 31 Victoria Langenheim, Tammy L. Surko, Phillip A. Armstrong, Jonathan C. Matti The morphology and anatomy of a Miocene long-runout landslide, Old Dad Mountain, California: implications for rock avalanche mechanics �������������������������������������������������������������������������������������������������� 38 Kim M. Bishop The discovery of the California Blue Mine ��������������������������������������������������������������������������������������������������� 44 Rick Kennedy Geomorphic evolution of the Morongo Valley, California ���������������������������������������������������������������������������� 45 Frank Jordan, Jr. New records
    [Show full text]
  • The Early Utilization and the Distribution of Agave in The
    University of New Mexico UNM Digital Repository UNM Bulletins Scholarly Communication - Departments 1938 The ae rly utilization and the distribution of agave in the American southwest Edward Franklin Castetter Willis Harvey Bell Alvin Russell Grove Follow this and additional works at: https://digitalrepository.unm.edu/unm_bulletin Recommended Citation Castetter, Edward Franklin; Willis Harvey Bell; and Alvin Russell Grove. "The ae rly utilization and the distribution of agave in the American southwest." University of New Mexico biological series, v. 5, no. 4, University of New Mexico bulletin, whole no. 335, Ethnobiological studies in the American Southwest, 6 5, 4 (1938). https://digitalrepository.unm.edu/unm_bulletin/31 This Article is brought to you for free and open access by the Scholarly Communication - Departments at UNM Digital Repository. It has been accepted for inclusion in UNM Bulletins by an authorized administrator of UNM Digital Repository. For more information, please contact [email protected]. hlliig4 The University olNewMexico Bulletin 1 Ethnobiolbgical Studies in the American SouthweSt VI. \The Early Utilization and the Diftribution ofAgave in the American Southweft EDWARD F. CASTETTER, WILLIS H. BELL and ALVIN R. GROVE • .~ ~ r v~r4..f.2.,,",,~- A , ,-' "W'/ I))j j'A1' WJl\( ;JJ;,£~/:(Jcu~~/ HI" I' ~~fi!:~~e . M>rX~;;fre~ UNIVERSITY OF NEW ...//f ':iT' 1938 . Price 50 cents .':.W\~) e.s<:-f1} Qr~: rvJrl The University of New Mexico Vl5 . ,r Bulletin ~('J I 'j"' Ethnobiological Studies In the American Southwest VI. The Early Uttlization and the Distribution ofAgave in the American Southrzvest By EDWARD F. CASTETTER WILLIS H. BELL ALVIN R. GROVE THE UNIVERSITY OF NEW MEXICO BULLETIN Whole Number 335 December 1, 1938 Biological Series, Vol.
    [Show full text]
  • Genetic Origins and Population Status of Desert Tortoises in Anza-Borrego Desert State Park, California: Initial Steps Towards Population Monitoring
    G ENETIC ORIGINS AND POPULATION STATUS OF DESERT TORTOISES IN A NZA-BORREGO DESERT STATE PARK, CALIFORNIA: INITIAL STEPS TOWARDS POPULATION MONITORING Jeffrey A. Manning, Ph.D. Environmental Scientist California Department of Parks and Recreation Colorado Desert District 200 Palm Canyon Drive Borrego Springs, California 92004 November 2018 Manning, J.A. 2018. Genetic origins and population status of desert tortoises in Anza-Borrego Desert State Park, California: initial steps towards population monitoring. California Department of Parks and Recreation, Colorado Desert District, Borrego Springs, California. 89 pages. i Genetic Origins and Population Status of Desert Tortoises in Anza-Borrego Desert State Park, California: Initial Steps Towards Population Monitoring Final Report Jeffrey A. Manning, Ph.D., Author / Principle Investigator California Department of Parks and Recreation Colorado Desert District 200 Palm Canyon Drive Borrego Springs, California 92004 November 2018 Manning, J.A. 201 8. Genetic origins and population status of desert tortoises in Anza-Borrego Desert State Park, California: initial steps towards population monitoring. California Department of Parks and Recreation, Colorado Desert District, Borrego Springs, California. 89 pages. i FOREWORD The Desert tortoise (Gopherus sp.) was formally reported to science in 1861, and became the official California state reptile in 1972. Recent studies reveal three species, the Mojave desert tortoise (G. agassizii), Sonoran Desert tortoise (G. morafkai), and Sinaloan desert tortoise (G. evgoodei) (Murphy et al. 2011, Edwards et al. 2016; Figure 1). Range-wide declines in the Mojave desert tortoise population led California to prohibit the collection of this species in 1961. Despite this, it was emergency listed as federally endangered and state listed as threatened in 1989, and subsequently listed as federally threatened in 1990 (Federal Register 55, No 63, 50 CFR Part 17).
    [Show full text]
  • Soleglad, Fet & Lowe: Hadrurus “Spadix” Subgroup 17
    Soleglad, Fet & Lowe: Hadrurus “spadix” Subgroup 17 Figures 31–33 Comparisons of Hadrurus obscurus and H. spadix, metasomal segments II–III, ventral view, showing diagnostic setation located between the ventromedian (VM) carinae. 31. H. obscurus, male (pale phenotype, segment II length = 8.44 mm, segment III length = 9.26 mm), Bird Spring Canyon Road, Kern Co., California, USA. 32. H. obscurus, female (dark phenotype, segment II length = 5.02 mm, segment III length = 5.70 mm), Bird Spring Canyon Road, Kern Co., California, USA. 33. H. spadix, female (segment II length = 7.87 mm, segment III length = 8.36 mm), Apex Mine in Curly Hollow Wash, Washington Co., Utah, USA. 19). However, to support our suspicion, we have ex- As stated above the positions and numbers of chelal amined two H. obscurus specimens collected from the internal trichobothria are essentially identical in Ha- same locality where one has a carapace pattern of H. drurus obscurus and H. spadix, while both numbers and spadix and the other a pattern typical of H. obscurus (see positions differ in H. anzaborrego (see Fig. 19). H. Fig. 20 for color closeup images of these carapaces, and anzaborrego has three internal accessory trichobothria Figs. 9–10 for overall comparison with “arizonensis” whereas the other two species have two. Statistics group species). Based on these data, we suggest here that involving over 250 samples show that these numerical these carapacial pattern differences are analogous to differences are observed in over 87 % of the specimens those exhibited by the dark and pale phenotypes of H. examined (Fig.
    [Show full text]
  • Water Resources of Borrego Valley, San Diego County, CA
    WATER RESOURCES OF BORREGO VALLEY SAN DIEGO COUNTY, CALIFORNIA _____________ A Thesis Presented to the Faculty of San Diego State University _____________ In Partial Fulfillment of the Requirements for the Degree Master of Science in Geological Sciences _____________ by Steven Paul Netto Fall 2001 iii Copyright 2001 by Steven Paul Netto iv ACKNOWLEDGMENTS First and foremost I would like to thank my wife Patti. She has sacrificed much over the years while supporting me in so many ways that I cannot find words adequate to express the gratitude that I feel. She has always been there for me and has carried more than her share as I have been occupied with coursework and this thesis effort, while at many times postponing or altogether foregoing her own interests. To my parents, Arnold and Velma Netto, I owe so many thanks. They have frequently expressed their interest, support and encouragement, and from them I have experienced the deepest kindness and generosity. Inspiring words from my father have stuck with me while finishing this thesis, he reminded me that it would take a lot of tenacity, not just know how, to finally get it done. And to my mother, Joan Fordyce, I also owe a debt of gratitude, for always being there with her love, support and enthusiasm. I am very fortunate to have had the opportunity to work with Dr. David Huntley on this project. It has been an enlightening experience for me and I have learned much from him that I will carry with me throughout the rest of my career.
    [Show full text]
  • A . INTRODUCTION B . PURPOSE C. STUDY AREA USER NOTES for SALTON SEA REGION SANTA ANA NE (32 Quads)
    USER NOTES FOR SALTON SEA REGION SANTA ANA NE (32 quads) SAt'TON- EArNW (;1 quad) SANTA ANA SE (2 quads) SALTON Sbr 9W.(32 o, "uuads' EL CENTRO NW (24 quads) NATIONAL WETLAND INVENTORY MAPS A . INTRODUCTION The U .S . Fish & Wildlife Service's National Wetlands Inventory is producing maps showing the location and classification of wetlands and deepwater habitats of the United States . The Classification of Wetlands and Deepwater Habitats of the United States by Cowardin et al . is the classification system used to define and classify wetlands . Photo interpretation conventions, hydric soils lists and wetland plant lists are also available to enhance the use and application of the classification system . B . PURPOSE The purpose of the notes to users is threefold : (1) to provide localized information regarding the production of NWI maps, including specific imagery and interpretation discussion ; (2) to provide a descriptive crosswalk from wetland codes on the map to common names and representative plant species, and (3) to explain local geography, climate, and wetland communities . C . STUDY AREA Geography : The Salton Trough is located in southern California . This study area is composed of five different maps ; Santa Ana NE, SE, Salton Sea NW, SW and El Centro NW (see index map) . This area is situated within two ecoregion provinces ; the American Desert Province and the California Chaparral Province (Bailey 1980) . The California Chaparral Province (no sections) borders the entire valley on the southwest side, from Santa Ar,a NE to El Centro NW . This province is characterized by the Coast Mountain Range which have steep unstable slopes, sharp crests and narrow valleys .
    [Show full text]
  • Peninsular Bighorn Sheep 2016-17 Annual Report
    CALIFORNIA DEPARTMENT OF FISH AND WILDLIFE PENINSULAR BIGHORN SHEEP 2016-17 ANNUAL REPORT Photo By Jeff Young This report presents information on the status, distribution, and management of peninsular bighorn sheep from 1 January 2016 to 31 May 2017 Authors Janene Colby and Randy Botta South Coast Region California Department of Fish and Wildlife Peninsular Bighorn Sheep Annual Report 2016-17 Table of Contents Executive Summary……………………………………………….....1 Background……………………………………………………….........3 Population Size and Estimation………………………….……..3 Radio-Collar Status………………………………………………...…5 Cause-Specific Mortality and Survival………………………..5 Lamb Survival and Recruitment……………………………….10 Distribution and Movement…………………………………….12 San Jacinto Mountains………………………………..…….…...12 Northern Santa Rosa Mountains…………………...…...12 Central Santa Rosa Mountains………………………...........13 Southern Santa Rosa Mountains………………………....... 14 Coyote Canyon……….………………………………………........15 Northern San Ysidro Mountains…………………...….…15 Southern San Ysidro Mountains……………..…….…….16 Vallecito Mountains…………..………………………….…...17 Carrizo Canyon…………………………………………….….….18 Threats to Recovery…………………………………….……..…..19 San Jacinto Mountains…………………………..................19 Northern Santa Rosa Mountains……………………………....19 Central Santa Rosa Mountains………………….……....…..19 Southern Santa Rosa Mountains…………………….…...…21 Coyote Canyon…………………………………………….….…...21 Northern San Ysidro Mountains…………………..….……..22 Southern San Ysidro Mountains……………………….…....22 Vallecito Mountains…………………………………………..….22 Carrizo Canyon……………………………………………..….…..23
    [Show full text]
  • Warbler, Yellow-Rumped
    Wood Warblers — Family Parulidae 477 Yellow-rumped Warbler Dendroica coronata The Yellow-rumped Warbler is probably San Diego County’s most abundant winter visitor. If the White- crowned Sparrow exceeds it, it is not by much. Eucalyptus groves and other exotic trees planted in developed areas suit the Yellow-rumped Warbler at least as much as natural sage scrub, chaparral, and woodland. The birds are strongly concentrated in the coastal lowland but are found almost through- out the county, lacking only from the most rugged parts of the Anza–Borrego Desert. As a breeding species, however, the Yellow-rumped Warbler is a recent colonist, rare and confined to coniferous Photo by Anthony Mercieca forest on San Diego County’s highest mountains. Because almost all Yellow-rumped Warblers are readily distin- guished in the field as belong- ing to either the eastern or the western group of subspecies, and the status of each is so different, this account refers to them by their traditional names, Audubon’s Warbler for the yellow-throated western birds, Myrtle Warbler for the white-throated eastern ones. See under Taxonomy for the status of the Myrtle. Winter: San Diego County must be near the core of the Audubon’s Warbler’s winter range. The spe- cies is common to abundant 478 Wood Warblers — Family Parulidae Breeding distribution: Audu- bon’s Warbler is another of those birds, like the Fox Sparrow, Green-tailed Towhee, and Dusky Flycatcher, whose breeding habi- tat lies in an elevation zone bare- ly pierced by San Diego County’s highest peaks. The warblers are now of annual occurrence in the Cuyamaca Mountains, with up to eight, including five singing males, on Middle Peak (M20) 11 June 2000 (R.
    [Show full text]
  • Peninsular Bighorn Sheep Recovery 2011 Annual Report
    CALIFORNIA DEPARTMENT OF FISH AND GAME PENINSULAR BIGHORN SHEEP RECOVERY 2011 ANNUAL REPORT A cooperative effort by the California Department of Fish and Game, U.S. Fish and Wildlife Service, and California Department of Parks and Recreation Photo By Janene Colby This report presents information on the status, distribution, and management of peninsular bighorn sheep in eastern San Diego County and portions of Riverside and Imperial Counties, California, from January 1, 2011 through December 31, 2011. Report prepared by Janene Colby and Randy Botta TABLE OF CONTENTS SUMMARY...…………………………………………………………………………… 2 PROJECT PERSONNEL……………………………………………………………… 3 CDFG Resource Management and Air Services Divisions…........................... 3 CDFG South Coast Region………………………….……..……………...…… 3 RECOVERY PROGRAM OVERVIEW Telemetry Monitoring…..……………………….………….……………..…… 4 Population Size and Estimation…...………………………….…………..……. 5 Distribution and Movement………….…………………………………...…..... 7 Central Santa Rosa Mountains…………………………………….....…... 7 Southern Santa Rosa Mountains…………..……………………...……… 7 Coyote Canyon........................................................................................... 7 Northern San Ysidro Mountains……………………..…………...……… 9 Southern San Ysidro Mountains…………………….…………...………11 Vallecito Mountains.....……………………………………..……...…….13 Carrizo Canyon…...…………………………………………………….. 15 Survivorship….…………………………………...………………………..….. 17 Lamb Mortality Monitoring………..……………………………………...…. 19 2012 PROPOSED ACTIVITIES …………………………………………………... 19 1 SUMMARY This report
    [Show full text]