Recent research shows that significant energy can be saved in wireless sensor networks by using mobile elements (MEs) capable of carrying data mechanically. Though the use of MEs can reduce the energy consumption at each sensor node, it increases the latency of data transfer from a source node to the base station. To address this issue, we propose a collection-based approach in which a subset of nodes serves as data collection points (CPs) that buffer data originated from sources and transfer data to MEs when they arrive. This will shorten the trajectory of MEs, but will also increase energy consumption of network nodes. There is a trade-off between energy consumption and data delivery latency. In this paper, we introduce a Probabilistic Path Selection (PPS) algorithm to reduce the data collection delay for stochastic event detection scenario. Furthermore, we develop a heuristic algorithm and apply it to situations where CPs are used to enable a flexible trade-off between energy consumption and data delivery latency.