Comparative methods for assessing the age and of the red fox (Vulpes vulpes crucigera) in Central Romania

Abstract This study focuses on the anatomical-morphological and cranial characteristics of the red fox subspecies Vulpes vulpes crucigera Bechstein in Central Romania. A total of 70 skull specimens and 65 carcasses were examined, with morphological determinations and anatomical evaluations conducted to understand the variability within the local population. Craniometric analysis involved 32 specific measurements, and regression equations were derived to estimate the age of specimens based on measurable parameters. The study area encompassed diverse ecological conditions, spanning on an area of almost 75 000 ha, providing insights into the adaptability of red foxes. The results highlight the significance of total body weight in estimating age and suggest the potential for further research to refine population characterization. Two equations resulted from the regression model, which can help the age determination directly on the terrain. The Principal Component Analysis was applied to all specimens in the study to analyze their morphological characteristics, revealing significant variations in skull and body parameters. Extending this study to different regions of Europe can enhance our understanding of red fox variations in skull and anatomical characteristics.