Grizzly Bear Mortality in the Central Rockies Ecosystem, Canada
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University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies Legacy Theses 1998 Grizzly bear mortality in the central rockies ecosystem, Canada Benn, Bryon Benn, B. (1998). Grizzly bear mortality in the central rockies ecosystem, Canada (Unpublished master's thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/13074 http://hdl.handle.net/1880/26290 master thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca #FORMATION TO USERS This rnanusmpt has been mpmdwed from the rnkmfdrn master. UMI films the text dire from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this mpmductkn k do- upon th. quality of the copy submitted. Broken or indistinct print cokred or poor quality illustmtions and Phtqraphs, print bhWmmgh. shSmdad nwgins, snd hpmpf align- can adversely affect reprodudiorr. In the unlikely event that the author did not send UMi a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized cd~mt material had to be removed, a note will indithe delgtiorr. Oversize rnaMals (e.g., maps, drawings, charts) are reproduced by sedming the original, beginning at he upper left-hand comer and continuing horn left to right in equal sections with small ov-. Photographs induded in the original manuscript have beecr reproduced xerographically in this copy. Higher qualily 6' x W Madc and Mite photographic prints are available for any mographs or illustmtbm appearing in this coQy for an additional charge. Contad UMI ditectly to ofder. Bell 8 Howdl Infomation and Learning 300 North Zeeb Road, Ann Arbor, MI 481OS1346 USA Grizzly Bear Mortality in the Central Rockies Ecosystem, Canada by Bryon Benn Masters Degree Project, Faculty of Environmental Design, University of Calgary Prepared as part of the Eastern Slopes Grlnly Bear Project National Library BibhoWque nathak du Canada Acquisitions and Acquisitions et Bibliographic Services services bibliographiques 395 Wellington Street 395. We w- OttawaON KIAW OctawRm K1AONS Canada CaMda The author has granted a non- L'auteur a accorde une licence non exclusive licence allowing the exclusive perme$tant a la National Library of Canada to Biblioth-e nationale du Canada de reproduce, loan, distri'bute or sell reproduke, pr-, distnbuer ou copies of this thesis in microform, vendre des copies de cette these sous paper or electronic formats. la forme de microfiche/film, de reproduction sur papier ou sur format electronique. The author retains ownership of the L'auteur conserve la propriete du copyright in this thesis. Neither the droit d'autnn qui protege cette these. thesis nor substantial extracts f3om it Ni la these ni des extraits substantiels may be printed or othenvise de celIeci ne doivent &re imprimes reproduced without the author's ou autrement reproduits sans son permission. autorisation. I dedicate this research to #16 and #35, two young grizzly bars, whose fates can only be described as #naebs. EXECUTIVE SUMMARY The ecological integrity of the Central Rockies Ecosystem (CRE) is being compromised by resource exbaction, cattle production, timber harvesting, transportation conidors, and outdoor recreation. Thus, the grizzly bear b suffering continuous habiit degradation, and potentially unsustainable mortality rates in same regions of the CRE. Grinly bears, especialJy males, typically move through many jurisdictions with dierent management objectives. Outside of parks they are vulnerable to hunting, and habitat modification and loss -ated with myriad land uses. Inside protected areas, bears are often either displaced from quality habitat by human activities, or may become habituated or food-mdied, increasing their mortali risk The Eastern Slopes Grinfy Bear Project (ESGBP) was formed in response to a request for information about grin& bear habitat use, human impacts on bear habitat use, and bear demographics. This pruject responds to a part of that need by analysing grinly bear mortality throughout the CRE. Idivided the CRE into three study areas, 1) the CRE portion of Alberta, 2) the CRE portion of the East Kootenays, BC.. and 3) Banff. Kootenay, and Yoho National Parks. As there were no recorded grinly bear deaths in Kootenay National Park, analyses for the national park study area include only the cantiguous Banff and Yoho National Parks. Grizzly bear mortality and translocation databases and digital access data were provided by land management agencies from the CRE. Specific analyses corrducted varied among the jurisdictions based on the major causes of grin& bear death, and the quality of certain attributes of the data. The conclusions reached and recommendations offered are based on three assumptions, 1) the databases represent the minimum number of gmly bear deams and translocations, 2) the goal of management agencies is to maintain or enhance the present population size and distn'bub'm of grizzly bears in their respective jurisdictions, and 3) mational hunting of grinly bears is an acceptable use of the resource. For this research, mortalities are defined as dead bears and translocations of bean -de of their ecosystem of origin. The objectiues and methoddogies for this research were: mective 1. to prepare a synthesis of the historical and current mortality data and events that affectedgrinly bear survival in the CRE. mective 2 to develop a centralized grizzfy bear mortality database accessible to all agencies in the CRE. Methods. I conducted a review of the scientific and grey literature, government documents, contract documents, and graduate theses to prepare a summw of events important to g-ly bear suNival (Appendix 1). I integrated information from these souras with mottality and translocation databases supplied to construct an historical mortality database (Appendix 2), and up to date mortality databases for the three CRE study areas (Appendices 3.4, & 5). Obiectwe. 3. to summarize hurnan-caused mortality and total human-caused and harvest mortality rates. To anaiyse mortality rates spatially and temporally with respect to changing management policies. Methods. Human-caused grinly bear mortality was surnmarited by cause of death and the sex, age, and cohort of bears that died. I stratified mortality data by legal harvest and non spoR mortality. The Alberta study area was subdivided into Kananaskis Country (no hunting) and north of the Bow R. (hunting permitted). As there is no hunting in the national parks, only non sport mortality was analysed. I generated total human-caused mortality rates based on population estimates from each jurisdiction. Similiuty, harvest rnortalii rates were &mated for the provincial jun'sdictions. Temporally, mortalii rates were estimated and compared ammg periods defined by specific management policies in each jurisdiction. Some examples are changes from gened hunting seasons to limited enby hunts, regional scale road dosures, and impwed garbage management strategies. The total number of mo~rtiesis a conservative figure, as I used only the recorded deaths and tmnslocations, and did not apply correction factors for estimating unreported morblity. Objective 4. to generate a preliminary analysis of mortalii risk posed to grinly beam by human access into grinly habitat. Methods. I integtated accurate moltality locations and access data, and created zones of influence (201) of 500m around roads and front country developments (open to the public and 2WD accessible), and 200m zones around trails and bad< country develogments. In the East Kootenay region, ZOls were of 1000m width due to less accurate mortality locations avaihble. I performed elevational analyses on the Albem and Natianal Park data to describe the vertical diikrtion of mortalities. ResuI&. Human-related causes were the primary sources of grln)y bear mowity in the area (627 of 639 known mortalities). Grizzly bears spend much of the year at lower elevations in this region, and roads and trails usually follow valley bottoms, often negatively ii affecting bear use of riparian and montane habitats. Eighty-five percent of 462 human-caused grizzly bear deaths with known locations occurred in 201s along roads and trails and anund settlements. Area-concentrated kills occurred around Banff townsite, the village of Lake Louise, along Me Trans Canada Highway, and along roads and trails accassi-ngmany valley systems throughout the study area Planning for, and managing appropriate development and levels of access into grizzly bear habitat, such that encounters between humans and bears are minimized, is a critical issue with respect to managing grhdy bear mortality in the CRE. In the national wrk s- frufn 1971-96, there were 118 recorded humancaused grizzly bear deaths (107 in BNP, 11 in YNP and 0 in KNP). Problem wildlife control (PW) accounted for 72% of these mortalities followed by highway and railway mortalities a? 19%. The annual number of grizzly bear deaths (average 4.w~)dedined signikanUy into lhe 1980s. Total human-caused mortality rates were estimated at 8-1 O??% for the 1971-83 period and less than 29C during 1984-96. However, the female portion of this moWi(80%) for the period 1984-96 was higher than reported in any grizzly bear population. One hundred percent of 95 human-caused mortalities with known accurate locations fell within 500m of roads and front country developments, and 200m of trails and back country facilities (201s occupied 25% of the area of suitable habitat in the study area). Forty-six of these 95 mortalities occurred at park townsites and associated landfills (Lake Louise 26, Banff 17. Fad3). 19 took place at sld resorb and commercial lodges. and 16 ocarned at public campgrounds. Of 72 mortalities with month of WI known 57% happened dufing the berry season.