Grazing, abandonment and frequent mowing influence the persistence of the steppe marmot, Marmota bobak [Pâturage, abandon et fauche fréquente influencent la persistance de la marmotte des steppes, Marmota bobak]

Résumé

The goals of the study were to illustrate how parameters of steppe marmot settlements change after abandonment of livestock grazing, to evaluate differences in vegetation characteristics between grazed and abandoned habitats, to find the links between these characteristics and the persistence of marmot settlements and to establish whether it is possible to maintain the food base of marmots by applying frequently repeated mowing. Data were collected in 1991–2016 in the steppe marmot (Marmota bobak) settlement in the Regional Landscape Park “The Velykyi Burluk-Steppe” (Kharkiv Region, Northeastern Ukraine). We found that grazing prolongs the period of active plant growth and supports a regrowth during periods of intensive feeding of all age groups of marmots. In abandoned habitats the vegetation period ended before the end of active feeding of reproductive females and juveniles. This resulted in lower reproductive success, which determines a decrease in the population and may in the future result in a larger decline of settlements. Frequently repeated mowing by a lawnmower at a cutting height of 6–9 cm prolongs the vegetation period and maintains a water content in the plants similar to that of grazed habitats throughout the active season of steppe marmots. (13) Grazing, abandonment and frequent mowing influence the persistence of the steppe marmot, Marmota bobak. Available from: https://www.researchgate.net/publication/323969791_Grazing_abandonment_and_frequent_mowing_influence_the_persistence_of_the_steppe_marmot_Marmota_bobak [accessed Mar 27 2018]. Izvleček Cilj raziskave je bil ponazoriti kako se dejavniki naselbine/kolonije stepskega svizca spremenijo po opustitvi paše, ovrednotiti razlike v lastnostih vegetacije med pašenimi in opuščenimi habitati, najti povezavo med temi lastnostmi in obstojnostjo naselbin/kolonij stepskega svizca in ugotoviti ali je moč ohranjati osnovno hrano za svizce z pogosto košnjo. Podatke smo zbrali med letoma 1991 in 2016 v naselbini/koloniji stepskega svizca (Marmota bobak) v Regionalnem parku “Stepa Velykyi Burluk” (regija Kharkiv, severovzhodna Ukrajina). Ugotovili smo, da paša podaljša aktivno rast rastlin in omogoča ponovno rast v obdobju hranjenja svizcev vseh starostnih skupin. Na opuščenih habitatih se vegetacijska doba zaključi pred obdobjem hranjenja plodnih samic in mladičev. To se odrazi v manjšanem reproduktivnem uspehu in zmanjšanju populacije ter v prihodnosti tudi v večjem zmanjšanju števila naselbin/kolonij. Pogosta košnja s kosilnico na višini 6–9 cm podaljša vegetacijsko dobo in ohranja vsebost vlage v rastlinah, podobno kot paša stepskih svizcev med aktivno sezono.