Izbira gnezditvenega habitata poljskega Alauda arvensis Linnaeus, 1758 in čopastega škrjanca Galerida cristata (Linnaeus, 1758) na Dravskem polju

• Main Author: Kerček, Matjaž
• Other Authors: Janžekovič, Franc
• Format: Master Thesis
• Language: Slovenian
• Published: [M. Kerček] 2016
• Subjects: Alauda arvensis; Galerida cristata; izbor habitata; gnezditvena gostota; intenzivno kmetijstvo; habitat selection; breeding density; intensive agriculture; info:eu-repo/classification/udc/598.283.2(497.4Dravsko polje):591.5(043.2)
• Online Access: https://dk.um.si/IzpisGradiva.php?id=58020; https://dk.um.si/Dokument.php?id=93555&dn=; http://www.cobiss.si/scripts/cobiss?command=DISPLAY&base=cobib&rid=22300680&fmt=11

Namen raziskave je bil ugotoviti značilnosti gnezditvenega habitata poljskega in čopastega škrjanca. Ptice sem popisoval z metodo kartiranja teritorijev med aprilom in julijem 2006 na desetih vzorčnih ploskvah na Dravskem polju s skupno površino 367,8 ha. Povprečna gnezditvena gostota poljskega škrjanca je bila 2,0 teritorija na 10 ha, čopastega škrjanca pa 0,9 teritorija na 10 ha. Število teritorijev obeh vrst se med gnezditvenim obdobjem ni statistično značilno spreminjalo. Čopasti škrjanec je gnezdil samo na območjih s prodnato geološko podlago, medtem ko za poljskega škrjanca geološka podlaga ni bila pomemben dejavnik. 75 % teritorijev poljskih škrjancev je vsebovalo vsaj tri različne kmetijske kulture. Vsi analizirani teritoriji čopastega škrjanca so vsebovali vsaj štiri kmetijske kulture. Med višino in pokrovnostjo vegetacije ter gostoto obeh vrst škrjancev nisem odkril statistično značilnih korelacij. Ključni dejavnik za ohranjanje populacije čopastega škrjanca je ohranjanje gostega omrežja neasfaltiranih poti in cest ter drobne zemljiške razdrobljenosti z visokim deležem buč. Za ohranjanje populacije poljskega škrjanca so pomembna območja z majhnimi parcelami, saj omogočajo stabilno število teritorijev med celotnim gnezditvenim obdobjem. Priporočljivo bi bilo povečati delež površin v prahi. The main objective of the research was to determine the main features of the breeding habitat of Skylark and Crested lark. Birds were censused with territory mapping technique in breeding season between April and July 2006 on Dravsko polje on 10 plots with total area 367.8ha. Average breeding territory density for Skylark was 2.0 territories per 10 ha and for Crested lark 0.9 territories per 10ha. Typical for both species was great stability of territory numbers. Crested lark has bred only on areas with gravel bedrock. Type of bedrock was an not important factor for breeding of Skylarks. 75% of territories populated by Skylark contained at least three different crops, and all territories of Crested larks at least four crops. There were no statistically significant corellations between territory densitiy of each species and average vegetation height and coverage. The key measure for conservation of Crested lark population is to sustain dense network of unpaved roads and tracks and farming on small fields with high proportion of pumpkins. Sustaining of farming on small fields is also important for conservation of Skylark, because it enables the pairs to hold their territories throughout the entire breeding seasons and therefore allows more potential breeding attempts. It would be advisable to increase areas with set-aside.