Chronographic Variability of Morphological Characteristics in the Ural Population of the Racoon Dog (Nyctereutes procyonoides)

Changes in craniometric traits of the raccoon dog (Nyctereutes procyonoides) in the samples from one locality separated by a 30-year time interval were analyzed. Small differences in both metric and nonmetric cranial traits were found. Sexual dimorphism was expressed weakly. For a set of 13 metric traits, significant differences were found in young and adult males in samples separated by a 30-year time interval. No such differences were found in either young or adult females. Analysis of skull aberrations showed a slightly higher level of divergence for a number of traits. Several new phenes of nonmetric traits, which were absent in the 1990s sample, were found among individuals captured in the 2020s, indicating a certain increase in diversity in the raccoon dog population over the 30-year period. A weak chronographic variability of cranial features compared to other species of Canidae was found, which was attributed by the authors to a number of physiological peculiarities of the raccoon dog.