Communication and tracking capabilities during and immediately after a large-scale natural disaster are one of the most important components of speedy response and recovery. In that, it discovers affected people and connects them with their families, friends, and communities with first responders and/or their support computational systems. Capabilities of current mobile technologies can be expanded to become effective large-scale disaster tool aid. To facilitate effective communication and coordination across different parties and domains, ontologies are becoming crucial in providing assistance during natural disasters, especially where affected locations are remote, affected population is large and centralized coordination is poor. Although there are several existing competing methodologies with regard to as how an ontology may be built, there is not a single right way to build an ontology. Furthermore, there is not a (de facto standard) Disaster Relief Ontology, although separated related ontologies may be combined to create an initial version. This article discusses our on-going development of an ontology for a Communication and Tracking System (CTS), based on existing related ontologies, that is aimed to be used by mobile applications to support disaster relief at the real-time. For future work, this ontology will be used to provide a multi-disciplinary knowledge foundation in a distributed multi-agent based environment, where mobile devices, rescue workers and their organizations are modelled and functioned as distributed and collaborative agents to support each other in the event of a large-scale natural disaster.