Abstract
The proliferation of research on target detection and tracking in wireless sensor networks has kindled development of tracking continuous objects such as fires, bio-chemical material diffusion. In this paper, we propose an energy-efficient algorithm that detects and monitors a moving event region by selecting only a subset of nodes near object boundaries. The paper also shows that we can effectively reduce report message size. It is verified with simulation results that overall size of the report message as well as the number of nodes that transmit the report message to the sink can be significantly reduced especially when the density of nodes deployed over the network field is high.