In this paper we exemplify how to address environmental monitoring tasks with a gas-sensitive micro-drone and present two different approaches to locate gas emission sources. First, we sent the micro-drone in real-world experiments along predefined sweeping trajectories to model the gas distribution. The identification of the gas source location is made afterwards based on the created model. Second, we adapted two bio-inspired plume tracking algorithms that have been implemented so far on ground-based mobile robots. We developed a third bio-inspired algorithm, which is called “pseudo gradient-based algorithm”, and compared its perfomance in real-world experiments with the other two algorithms.Keywords: Anemotaxis, chemotaxis, micro UAV, bio-inspired, chemical sensing, gas distribution modeling, gas source localization, gas sensors, mobile sensing system, odor localization, olfaction, plume tracking, quadrocopter.