Hirvlaste suvine toitumine lehtpuudest ning nende asustustihedus Lääne-Saaremaal
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Kuupäev
2015
Kättesaadavus
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Abstrakt
Antud bakalaureusetöö kajastab hirvlaste suvist kärpimisaktiivsust, puuliigilisi eelistusi ning
asustustihedust Lääne-Saaremaal. Töö eesmärgiks on selgitada välja muutused lehtpuude
kärpimisintensiivsuses, toiduks eelistatud puuliigilises kooseisus ning hirvlaste
asustustiheduse muutusi aastail 2008-2014. Töös on kasutatud Karli Ligi poolt aastatel 2008-
2013 kogutud andmeid ning autori kogutud andmeid aastatel 2013-2014. Hirvlaste
kärpimisintensiivsuse määramiseks kasutati metoodikat, mille abil saab määrata hirvlaste
toidubaasi kasutust ja liigilist eelistamist toitumises. Asustustiheduse määramiseks kasutati
ekskrementloenduse meetodit. Hirvlaste keskmine kärpimisaktiivsus on neil aastail olnud
38%, mis tähendab, et alasid kasutab toitumiseks optimaalne arv hirvlasi. Lehtpuu liikidest
olid eelistatud haab, paakspuu, sarapuu, pihlakas ja paju. Põdra (Alces alces) ja punahirve
(Cervus elaphus) asustustihedus on neil aastail püsinud stabiilne, metskitse (Capreolus
capreolus) arvukus on langenud ligi poole võrra.
The thesis at hand concentrates on the summer browsing of cervids, preferences of feeding on woody plants and the population density of cervids in Western-Saaremaa. The purpose of this thesis is to show the changes in the browsing intensity, feeding preferences and population density of deer during 2008-2014. The study bases on the data gathered by Karli Ligi between 2008 and 2013 and the author between 2013 and 2014. To measure the browsing intensity of the cervids the author used a methodology what can be used to determine the feeding preferences of the cervids. To measure the population density the method of counting winter pellet groups was used. The average browsing activity of cervids has been 38% during the research period, therefore the researched areas was populated by the optimal number of cervids. The most preferred deciduous tree species for browsing were aspen, buckthorn, common hazel, rowan and willow. The population density of moose (Alces alces) and red deer (Cervus elaphus) has been stable throughout the research period, the population of the roe deer (Capreolus capreolus) has fallen almost 50% during aforementioned period.
The thesis at hand concentrates on the summer browsing of cervids, preferences of feeding on woody plants and the population density of cervids in Western-Saaremaa. The purpose of this thesis is to show the changes in the browsing intensity, feeding preferences and population density of deer during 2008-2014. The study bases on the data gathered by Karli Ligi between 2008 and 2013 and the author between 2013 and 2014. To measure the browsing intensity of the cervids the author used a methodology what can be used to determine the feeding preferences of the cervids. To measure the population density the method of counting winter pellet groups was used. The average browsing activity of cervids has been 38% during the research period, therefore the researched areas was populated by the optimal number of cervids. The most preferred deciduous tree species for browsing were aspen, buckthorn, common hazel, rowan and willow. The population density of moose (Alces alces) and red deer (Cervus elaphus) has been stable throughout the research period, the population of the roe deer (Capreolus capreolus) has fallen almost 50% during aforementioned period.
Kirjeldus
Märksõnad
bakalaureusetööd