SUMMARY
The role scent marks play in territory maintenance is considered specifically in terms of how they may achieve the goal of limiting intruders from exploiting defended resources. In large territories, where permanent monitoring is not possible, scent marks must be able to function in the temporary absence of the residents. Scent mark density indirectly communicates to intruders the potential of being encountered by the owners, while the marks themselves intrinsically threaten intruders with physical attack if they are encountered. Territory residents must carry out this threat if intruders are encountered, otherwise there will be no deterrent to intruders and territory maintenance will be redundant. The response of intruders to scent marks will depend on their motivation and the value of the resource to be exploited. Thus, although scent marks are unlikely to exclude totally intruders from exploiting resources within a territory, they may limit the degree (time and space) to which the territory is intruded and hence indirectly protect its resources.