Cabinet-Yaak Grizzly Bear Recovery 2016 Research and Monitoring Progress Report
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CABINET-YAAK GRIZZLY BEAR RECOVERY AREA 2016 RESEARCH AND MONITORING PROGRESS REPORT PREPARED BY WAYNE F. KASWORM, THOMAS G. RADANDT, JUSTIN E. TEISBERG, ALEX WELANDER, MICHAEL PROCTOR, AND HILARY COOLEY 2017 UNITED STATES FISH AND WILDLIFE SERVICE GRIZZLY BEAR RECOVERY COORDINATOR'S OFFICE UNIVERSITY OF MONTANA, MAIN HALL ROOM 309 MISSOULA, MONTANA 59812 (406) 243-4903 1 This annual report is cumulative and represents data collected since the inception of this monitoring program in 1983. New information collected or made available to this study is incorporated, reanalyzed, and summarized annually. Information in this report supersedes previous reports. Please obtain permission prior to citation. Cite this report as follows: Kasworm, W. F., T. G. Radandt, J.E. Teisberg, A. Welander, M. Proctor, and H. Cooley. 2017. Cabinet-Yaak grizzly bear recovery area 2016 research and monitoring progress report. U.S. Fish and Wildlife Service, Missoula, Montana. 101 pp. ABSTRACT Sixteen grizzly bears were monitored with radio collars during portions of 2016. Research monitoring included seven females (three adults and four subadults) and nine males (five adults and four subadults) in the Cabinet-Yaak ecosystem (CYE). Two bears of these bears were from the Cabinet Mountains (1 subadult male and 1 subadult female) and part of the augmentation program. Grizzly bear monitoring and research has been ongoing in the Cabinet Mountains since 1988 and in the Yaak River since 1986. Sixty-eight resident bears have been captured and monitored through telemetry in the two areas from 1986-2016. Research in the Cabinet Mountains indicated that only a small population remained as of 1988. Concern over persistence of grizzly bear populations within this area resulted in a pilot program in 1990 that tested population augmentation techniques. Four subadult female bears with no history of conflicts with humans were captured in southeast British Columbia and moved to the Cabinet Mountains for release during 1990–94. Three of four transplanted bears remained within the target area for at least one year. Hair snag sampling and DNA analysis during 2000–04 identified one of the original transplanted bears. The animal was a 2 year-old female when released in 1993. Genetic analysis conducted in 2005 identified at least 3 first generation offspring and 2 second generation offspring from this individual. The success of the augmentation test program prompted additional augmentation in cooperation with Montana Fish Wildlife and Parks (MTFWP). Nine female bears and 6 male bears were moved from the Flathead River to the Cabinet Mountains during 2005–16. Three of these individuals died during their first year from human related causes. Two were illegally shot and one was struck by a train. Five bears left the target area for the augmentation effort. Numbers of females with cubs in the Cabinet-Yaak grizzly bear recovery zone (CYE) varied from 1–3 per year and averaged 2.3 per year from 2011–16. Eleven of 22 bear management units had sightings of females with young during 2011–16. Human caused mortality averaged 1.7 bears per year (0.2 females and 1.5 males) from 2011-16. Ten grizzly bears (1 female and 9 males) died due to known or probable human causes during 2011-2016, including one adult female (human, under investigation), 4 adult males (two human, under investigation, one mistaken as a black bear, and a self-defense), 4 subadult males (black bear mistaken identity, two self-defense, and one poaching), and one male cub (human, under investigation). Using all methods of detection (capture, rub tree DNA, corral DNA, photos), we detected a minimum 35 individual grizzly bears in 2016. Thirteen bears were detected in the Cabinets (7 males, 6 females). Twenty-three bears were detected in the Yaak (14 male, 8 female, 1 unknown sex). One bear was documented in both the Cabinets and the Yaak. Sex- and age-specific survival and reproductive rates yielded an estimated finite rate of increase () of 1.016 (95% C.I. 0.926–1.085) for 1983–2016 using Booter software with the unpaired litter size and birth interval option. Finite rate of population change was an annual 1.6% for 1983–2016. The probability that the population was stable or increasing was 66%. Berry counts indicated average production for huckleberry and less than average production for serviceberry, buffaloberry, and mountain ash during 2016. 2 TABLE OF CONTENTS PAGE ABSTRACT ................................................................................................................................ 2 TABLE OF CONTENTS ............................................................................................................. 3 INTRODUCTION ....................................................................................................................... 5 OBJECTIVES ............................................................................................................................ 6 A. Cabinet Mountains Population Augmentation:................................................................... 6 B. Recovery Zone Research and Monitoring: ........................................................................ 6 STUDY AREA ............................................................................................................................ 7 METHODS ................................................................................................................................. 9 Grizzly Bear Observations ...................................................................................................... 9 Survival and Mortality Calculations ......................................................................................... 9 Reproduction .........................................................................................................................10 Population Growth Rate ........................................................................................................10 Capture and Marking .............................................................................................................11 Hair Sampling for DNA Analysis ............................................................................................12 Radio Monitoring ...................................................................................................................13 Scat analysis .........................................................................................................................14 Isotope analysis ....................................................................................................................14 Berry Production ...................................................................................................................14 RESULTS AND DISCUSSION ..................................................................................................15 Grizzly Bear Observations and Recovery Plan Criteria..........................................................15 Cabinet Mountains Population Augmentation ........................................................................23 Cabinet-Yaak Hair Sampling and DNA Analysis ....................................................................25 Grizzly Bear Genetic Sample Summary ................................................................................27 Known Grizzly Bear Mortality ................................................................................................30 Grizzly Bear Mortality, Reproduction, Population Trend, and Population Estimate ................32 Grizzly Bear Survival and Cause-Specific Mortality ...........................................................32 Augmentation Grizzly Bear Survival and Cause-Specific Mortality ....................................34 Management Grizzly Bear Survival and Cause-Specific Mortality ......................................34 Population Trend ...............................................................................................................35 Capture and Marking .............................................................................................................37 Cabinet Mountains ............................................................................................................37 Yaak River, Purcell Mountains South of BC Highway 3 .....................................................38 Moyie River and Goat River Valleys North of Highway 3, British Columbia .......................38 3 Population Linkage Kootenai River Valley, Montana .........................................................38 Population Linkage Clark Fork River Valley, Montana .......................................................38 Population Linkage Interstate 90 Corridor, Montana and Idaho .........................................38 Population Linkage Highway 95 Corridor, Idaho ................................................................38 Radio Telemetry Monitoring ..................................................................................................43 Black Bear – Linkage Research ........................................................................................43 Grizzly Bear Monitoring and Home Ranges .......................................................................46 Grizzly Bear Denning Chronology .........................................................................................49 Grizzly Bear Use of Habitat Components ..............................................................................51