The implications of territoriality for the social system of the European pine marten Martes martes (L, 1758)

The social organisation and the structure of a population of pine martens in the northern part of a low mountain range in northwestern Germany are investigated in a long-term study. Observations by radio-tracking and data from capture-recapture of 12 pine martens (6 females, 6 males) show at least four differences in territory size: the seasonal, the intersexual, that due to the mating system, and that due to genesis. The territories are held over several years. Males already create summer territories in early spring, before the birth of the offspring and about 5 months before the mating season. They leave these only in late autumn and move into their winter territories. This extensive seasonal territorial behaviour cannot only be explained as mate guarding, but also as offspring guarding by creating a territory-tie. Genetic paternity could be determined by the DNA-fingerprinting method. Parental care of the young by the territorial male was never observed. But males show a distinct guarding behaviour by creating a territorial tie. This social structure is called a male-mother-family.