Activity and neonatal mortality of roe deer fawns

Za mladiče evropske srne (Capreolus capreolus) je značilna velika smrtnost. Študija je proučevala prostorsko aktivnost mladičev srnjadi v kritičnem obdobju, to je prve 3–4 tedne življenja, in vzroke njihove zgodnje smrtnosti. Podatke o prostorski aktivnosti v kritičnem obdobju smo pridobili s spremljanjem mladičev, opremljenih z mikro ušesnimi sponkami z vgrajenimi VHF-oddajniki, za analizo vzrokov zgodnje smrtnosti pa iz baze podatkov Lovskega informacijskega sistema Lisjak. Vsi podatki so bili obdelani v programu Microsoft Excel in/ali GIS programski opremi ArcGIS Pro. Metodološko je iskanje mladičev najuspešnejše pri opazovanju z visokih prež. Uporaba termovizijskih kamer je učinkovita za detekcijo živali v vertikalnem pogledu. Mladiči se v prvem mesecu življena zadržujejo predvsem na travnikih in v gosti gozdni vegetaciji na območjih, premera 100–150 m. Njihovi premiki so ob odsotnosti motečih dejavnikov krajši od 50 m. Glede na registrirane primere, tj. tiste, ki jih najdejo in evidentirajo lovci, v prvem poletju 2/3 poginulih mladičev pogine zaradi košnje, sledita promet in plenilstvo. Zgodnja smrtnost zaradi košnje vrhunec doseže v začetku junija, sledi vrhunec zaznanega plenjenja, vrhunec smrti zaradi prometa pa je konec avgusta. V neonatalnem obdobju celokupno pogine več mladičev ženskega spola. Prostorsko je razporeditev smrti mladičev glede na spol v Sloveniji precej enakomerna. Relativna evidentirana neonatalna smrtnost in relativna gostota srnjadi nista premosorazmerni. Evidentirano največ mladičev pogine 500–1000 m od naselij. Glede na oddaljenost od gozdnega roba jih največ pogine v rangu 0–200 m. Območja, na katerih pride do smrti, najpogosteje dosegajo vrednosti indeksa fragmentiranosti gozda 6000–7500.V prvem letu življenja največ osebkov pogine zaradi odstrela. Med ostalimi evidentiranimi vzroki prednjači promet, sledita mu košnja in plenilstvo. Pri tem največ mladičev zaradi povozov pogine v oktobru, zaradi evidentiranega plenjenja pa v decembru. Pomembno je, da se ob interpretaciji rezultatov zavedamo, da ti temeljijo na podatkih o evidentirani smrtnosti, zato zelo verjetno ne odražajo dejanskega stanja v naravi.European roe deer (Capreolus capreolus) fawns are characterized by their high mortality rate. This study examined the spatial activity of young fawns during the critical period and the causes of their neonatal mortality. Data on the spatial activity during the critical period was obtained by monitoring subjects equiped with micro-ear clips with built-in VHF transmitters, and data for the analysis of neonatal mortality was taken from Hunting Information System Lisjak database. All data was processed in Microsoft Excel and/or ArcGIS Pro software. Methodologically, the search for fawns was most successful when observing from high perches. The use of thermal imaging cameras is effective for detecting animals in a vertical view. During the first month of life, the fawns stay mostly in meadows and in dense forest vegetation in areas of 100–150 m in diameter. Their movement in the absence of disturbing factors are shorter than 50 m. In their first summer, 2/3 of fawns are recorded killed by mowing, followed by traffic and predation. Early mortality caused by mowing peaks in early June, followed by predation and traffic mortality peaks in late August. In the neonatal period, many more female fawns die. Spatial distribution of mortality by gender in Slovenia is quite even. Relative recorded neonatal mortality and relative density of fawns are not directly proportional. In the records, maximum number of cubs die 500–1000 m from human settlements. Depending on the distance from the forest edge, most of them die in the range of 0–200 m. The areas where death occurs most often reach values of the forest fragmentation index of 6000–7500. In the first year of life, most individual die due to shooting (hunting). Among the other causes, traffic leads the way, followed by mowing and predation. Most of tbe fawns die from being run over in October, and from predation in December. It is important to be aware when interpreting the results that they are based on data on recorded mortality and therefore do not reflect the state in nature