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dc.contributor.authorEchols, Kim Needhamen_US
dc.date.accessioned2011-08-06T16:06:21Z
dc.date.available2011-08-06T16:06:21Z
dc.date.issued2000-06-09en_US
dc.identifier.otheretd-08152000-19430055en_US
dc.identifier.urihttp://hdl.handle.net/10919/10108
dc.description.abstractWe measured black bear (Ursus americanus) reproduction and cub survival during 1994 - 1998, and 1995 - 1999, respectively, in the George Washington and Jefferson National Forests in Virginia to determine age-specific and overall cub production and cub survival. We observed females in estrus between 6 June and 22 August; the mean date of estrus was 17 July. Ages of primiparity ranged between 3 and 5 years with an average of 3.36 years (n=11, SE=0.15). Average litter size for 1995 - 1998 was 2.32 cubs/litter (SE=0.11, n=53) and 85.7% of available females ≥ age 4 (those not accompanied by cubs) reproduced in a given den season. We monitored 98 (48M:50F) black bear cubs equipped with expandable radio-collars (Higgins 1997) or radio transmitters implanted subcutaneously between 1995 and 1999 to estimate cub survival. Kaplan-Meier staggered entry analysis provided 306-day survival rates for 82 cubs. The survival estimates for males and females were 73% (0.49, 0.96) and 91% (0.80, 1.00), respectively. The overall 306-day survival rate for all cubs was 81% (0.67,0.94) using Kaplan-Meier and 76% (0.63, 0.92) using Heisey-Fuller (Mayfield) methods. We also evaluated the utility of radio transmitters implanted subcutaneously in 42 (21M:21F) wild black bear (Ursus americanus) cubs from 2 study areas in Virginia between 1996 and 1999 to monitor first year cub survival. More than 64% (27 of 42) of the implants fell out prematurely (2-198 days), and 16.6% (7 of 42) failed for unknown reasons. Less than 5% (2 of 42) of these cubs denned wearing failed implants, and 9.5% (4 of 42) experienced mortality less than 1 month after implant surgery. About 9.5% (4 of 42) of implanted black bear cubs wore working transmitters through to the following den season.en_US
dc.format.mediumETDen_US
dc.publisherVirginia Techen_US
dc.relation.haspartKimsETD.pdfen_US
dc.rightsI hereby grant to Virginia Tech or its agents the right to archive and to make available my thesis or dissertation in whole or in part in the University Libraries in all forms of media, now or hereafter known. I retain all proprietary rights, such as patent rights. I also retain the right to use in future works (such as articles or books) all or part of this thesis or dissertation.en_US
dc.subjectreproductionen_US
dc.subjectVirginiaen_US
dc.subjectimplantsen_US
dc.subjectsubcutaneousen_US
dc.subjectcub survivalen_US
dc.subjectUrsus americanusen_US
dc.subjectblack bearsen_US
dc.titleAspects of Reproduction and Cub Survival in a Hunted Population of Virginia Black Bearsen_US
dc.typeThesisen_US
dc.contributor.departmentFisheries and Wildlife Sciencesen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineFisheries and Wildlife Sciencesen_US
dc.contributor.committeechairVaughan, Michael R.en_US
dc.contributor.committeememberKirkpatrick, Roy L.en_US
dc.contributor.committeememberHaas, Carola A.en_US
dc.contributor.committeememberHallerman, Eric M.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-08152000-19430055en_US
dc.date.sdate2000-08-15en_US
dc.date.rdate2001-08-17
dc.date.adate2000-08-17en_US


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