Prostorska razporeditev in izbira dreves za hranjenje pri evrazijskemu bobru

Juršič, Klemen (author), Krofel, Miha (mentor), Graf, Patricija M. (comentor)

Po stoletjih odsotnosti se je evrazijski bober vrnil in razširil po večini slovenskih rek. Njegova aktivnost v okolju in vpliv na obrežne ekosisteme se je že začel odražati v konfliktnosti z ljudmi, žal pa o bobru v našem okolju ne vemo prav veliko. Cilj naloge je bilo ugotoviti, kje v prostoru bober podira drevesa in ali selektivno izbira določene drevesne vrste glede na njihovo razpoložljivost v prostoru. Na izbranih devetih lokacijah na reki Krki z njenimi pritoki smo določili meje teritorija, popisali vsa podrta in obžrta drevesa in popisali število vseh razpoložljivih dreves po vrstah v pasu 5 metrov od bregov vodotokov. Ugotovili smo, da bober drevesa podira po svojem celotnem teritoriju, številčnost pa se z oddaljenostjo od bobrišča zmanjšuje. Vpliv na prostorsko razporeditev podrtih dreves imajo verjetno tudi sekundarne strukture, kot so naravni, umetni in bobrovi jezovi. Glede na velikost in debelino dreves, bober preferenčno izbira debla, ki so tanjša od 10 cm. Čeprav v veliki meri uporablja lesko (Corylus avellana) in vrbe (Salix sp.), glede na razpoložljivost v naravi izbira tudi nekatere ostale vrste, kot so jelše (Alnus sp.), glog (Crataegus oxyacantha) in hrast (Quercus sp.), če so le na razpolago. V svojo prehrano je nepričakovano vključil tudi bezeg (Sambucus nigra).

• Language: Slovenian
• Keywords: Castor fiber, hranjenje, izbira dreves, prostorska razporeditev
• Work type: Master's thesis/paper
• Organization: BF - Biotechnical Faculty
• Year: 2019
• PID: 20.500.12556/RUL-113010
• COBISS.SI-ID: 5326671
• Publication date in RUL: 29.11.2019

JURŠIČ, Klemen, 2019, Prostorska razporeditev in izbira dreves za hranjenje pri evrazijskemu bobru [online]. Master’s thesis. [Accessed 14 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=113010

Secondary language

• Language: English
• Title: Spatial distribution and selection of trees used by Eurasian beaver

Abstract

The Eurasian beaver returned after a few centuries of absence and spread across most rivers in Slovenia. Unfortunately, no much is known about beavers in our environment, though their activity and impact on riparian ecosystems already begun to result in conflicts with humans. The main task of this work was to find out where in their territory beavers cuts down trees and whether the selection of a certain tree species depends on its availability. We chose nine locations on the Krka River and its tributaries, determined the territory boundaries, counted all trees that were cut down or gnawed on by beaver and recorded the number of all available trees per species in a parameter of 5 meters from the river banks. We found that beavers cut trees throughout their territory and the number is decreasing with the distance from the beaver lodge. Secondary structures, such as natural, artificial and beaver dams, probably have a great impact on spatial distribution of cut down trees. Beavers prefer stems with less than 10 cm in diameter, depending on the size and thickness of trees. Although in most cases beavers choose hazel (Corylus avellana) and willow trees (Salix sp.), they prefer other species such as alder (Alnus sp.), hawthorn (Crataefus oxyacantha) and oak (Quercus sp.) if available. Surprisingly they also included elder (Sambucus nigra).

• Keywords: Castor fiber, feeding, tree selection, spatial distribution