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Z namenom prepoznavanja vzrokov za velik upad številčnosti populacije smrdokavre na Goričkem smo v letih 2012 in 2013 izvedli prvo ekološko raziskavo o prehrani in izboru prehranjevalnih habitatov smrdokavre. Prehrano smrdokaver smo določili na podlagi posnetkov plena, s katerim so starši hranili mladiče (n = 2895). Bramorji so bili najbolj dominanten plen (35,4 % plena in 81,3 % biomase plena). Z ličinkami skarabejev, metuljev in dvokrilcev ter s poljskimi murni in pajki so se prehranjevale redkeje. Frekvenca hranjenja je bila največja v obeh obdobjih najbolj intenzivne rasti mladičev (starost mladičev med 7 in 20 dni). Za najpomembnejši prehranjevalni habitat smrdokaver so se izkazali košeni travniki in travnata dvorišča, v manjši meri pa so plen nabirale tudi na peščenih kolovozih in košenih robovih cest. Vsem habitatom je skupna nizka vegetacija s posameznimi zaplatami golih tal. Na teh odprtih habitatih, ki so življenjski prostor edafskih žuželk, smrdokavre lažje in bolj učinkovito lovijo. Velikost domačega okoliša smo ugotavljali z dvema metodama (MBG in MCP). Največja velikost domačega okoliša je bila 57,7, oziroma 42,9 ha, pri čemer odstotek prehranjevalnih habitatov v domačem okolišu ni presegal 18 %. Na podlagi rezultatov teh raziskav zaključujemo, da je za varstvo smrdokavre na Goričkem treba izvesti dva sklopa ukrepov: (1) najmanj ohraniti sedanji delež ekstenzivnih travnikov s postopnim povečanjem njihovega odstotka na 20 % rabe tal do leta 2020 in ohranjati tradicionalne elemente kulturne krajine (peščeni in travnati kolovozi, travnata dvorišča) ter (2) povečati število gnezditvenih mest z namestitvijo 200 gnezdilnic na območjih pomanjkanja naravnih dupel ob sočasnem spodbujanju sajenja visokodebelnih sadovnjakov. In 2012 and 2013, the selection of foraging habitats and the diet of Hoopoe were studied to identify the causes for population decline of Hoopoe in Goričko. The diet was determined using recordings of prey that was brought to chicks by parents (n = 2895). Molecrickets were the most dominant prey (35,4 % frequency and 81,3 % biomass of prey). More rarely chicks were fed with the larvae of scarab beetles, butterflies and true flies, field crickets or spiders. Feeding frequency was the highest in the period of most intensive chick growth (chicks age between 7 and 20 days). Selection of foraging habitats was determined by observation of birds during foraging. Hoopoes foraged mostly in the mowed meadows and grassy yards, and to a lesser extent on sandy tracks and mowed edges of the roads, as well. These were all habitats with low vegetation and patches of bare ground. Such open areas, inhabited by edaphic insects, enable Hoopoes easier and more efficient foraging. The size of home range was determined by the following two methods - Minimum Bounding Geometry and Minimum Convex Polygon. The maximum size of home range was 57,7 ha and 42,9 ha, respectively, while the percentage of foraging habitats within the home range did not exceed 18 %. Based on the results of the study we recommend the following conservation measures for more effective Hoopoe conservation in Goričko area: (1) maintaining at least the present range of extensive meadows with their gradual increase toward 20 % in land use by 2020 (2) increasing the number of avaible nesting sites with the installation of 200 nest-boxes in areas without natural cavities while simultaneously promoting the planting of traditional orchards. |
