Offspring emerge 3 weeks later (Moehlman, 1979), coinciding with the fur seal pupping season. Alloparental care may offset costly trade-offs between offspring care at the den and food acquisition away from the den. We therefore predict larger group sizes further from the food resource where costs of acquiring food (time and energy) are greatest. Studies across the jackals’ range report that the species is territorial, with each mated pair defending a shared territory (Loveridge PD-1/PD-L1 inhibitor & Nel, 2004). However, previous radio-telemetry studies at CCSR have suggested territoriality breaks down (Hiscocks & Perrin, 1988; Gowtage-Sequeira, 2005) based on large

home-range overlap, high foraging densities and lack of territorial behaviour, though observational study was limited to opportunistic sightings. While there have been many interpretations of territoriality in the

literature (see Maher & Lott, 2000 for review) it is generally accepted that territoriality is the maintenance and defence of an area through self-advertisement and aggressive/threat behaviour. A territory is the area actively maintained and defended. By definition, observations of self-advertisement and aggressive/threat behaviour are thus needed to detect territoriality. In this paper, we challenge through behavioural study the conclusion of past studies that territoriality breaks down and we investigate the jackals’ social structure (group size, presence of subordinates) and spatial organization (territory size and commuting system) in relation

to the fur seal colony. Black-backed jackal groups were located within a 250 km2 area of TSA HDAC research buy the National 上海皓元医药股份有限公司 West Coast Recreation Area, which encompasses the 60 km2 CCSR (21°46′S/14°00′E). This coastal area receives 0–50 mm rainfall annually (Barnard, 1998) with most moisture originating from coastal fog banks. The coastline comprises sandy beaches with hummock vegetation (e.g. Zygophyllum clavatum, Psilocaulon kuntzei) while salt flats, gravel plains and schist mountains inland support lichen fields and sparse vegetation in ephemeral riverbeds. The only other terrestrial carnivore is a small transient population of brown hyena Hyaena brunnea. The area is uninhabited except for a ranger post, salt mine and lodge. Consequently, jackals are subject to limited human disturbance and active during the day. There are two artificial freshwater holes (c. 1 m diameter) located by the CCSR ranger post and Cape Cross Lodge. A salt road connects Swakopmund town and the Skeleton Coast National Park. Off-road driving is prohibited, with vehicles restricted to the few existing tracks. Thus our study concentrated 20 km north along the coast and 12 km inland. CCSR was established to protect one of Namibia’s largest permanent Cape fur seal breeding colonies, estimated at 187 000 pups, cows and bulls (Gowtage-Sequeira, 2005). The colony stretched 5.24 km along the coastline during our study (Fig. 1).