{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/10108"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/10108","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Aspects of Reproduction and Cub Survival in a Hunted Population of Virginia Black Bears","abstract":"We 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.","abstract_html":"We 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.","abstract_has_math":false,"creators":["Echols, Kim Needham"],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Fisheries and Wildlife Sciences","degree_department":"Fisheries and Wildlife Sciences","school":null,"contributors":[],"advisors":[],"committee_chairs":["Vaughan, Michael R."],"committee_members":["Kirkpatrick, Roy L.","Haas, Carola A.","Hallerman, Eric M."],"year":2000,"date_issued":"2000-06-09","date_published":"2000-06-09","updated_at":"2026-07-22T22:19:10Z","subjects":["Reproduction","Virginia","implants","subcutaneous","cub survival","Ursus americanus","black bears"],"languages":[],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-08152000-19430055"],"render_values":[{"text":"etd-08152000-19430055","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/10108","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Vaughan, Michael R."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Kirkpatrick, Roy L.","Haas, Carola A.","Hallerman, Eric M."]},{"key":"dc:contributor.department","label":"Department","values":["Fisheries and Wildlife Sciences"]},{"key":"dc:creator","label":"Author","values":["Echols, Kim Needham"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2011-08-06T16:06:21Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2011-08-06T16:06:21Z","2001-08-17"]},{"key":"dc:date.issued","label":"Date","values":["2000-06-09"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Fisheries and Wildlife Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Reproduction","Virginia","implants","subcutaneous","cub survival","Ursus americanus","black bears"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-08152000-19430055"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/10108"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["We 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."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["ETD"]},{"key":"dc:title","label":"Title","values":["Aspects of Reproduction and Cub Survival in a Hunted Population of Virginia Black Bears"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Vaughan, Michael R."],"dc:contributor.committeemember":["Kirkpatrick, Roy L.","Haas, Carola A.","Hallerman, Eric M."],"dc:contributor.department":["Fisheries and Wildlife Sciences"],"dc:creator":["Echols, Kim Needham"],"dc:date.accessioned":["2011-08-06T16:06:21Z"],"dc:date.available":["2011-08-06T16:06:21Z","2001-08-17"],"dc:date.issued":["2000-06-09"],"dc:description.abstract":["We 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."],"dc:description.degree":["Master of Science"],"dc:format.medium":["ETD"],"dc:identifier.other":["etd-08152000-19430055"],"dc:identifier.uri":["http://hdl.handle.net/10919/10108"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["Reproduction","Virginia","implants","subcutaneous","cub survival","Ursus americanus","black bears"],"dc:title":["Aspects of Reproduction and Cub Survival in a Hunted Population of Virginia Black Bears"],"dc:type":["Thesis"],"thesis:degree_discipline":["Fisheries and Wildlife Sciences"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:10Z"}