A real-time visual multiple target tracker is demonstrated onboard a descending multirotor. Measurements of moving ground targets are generated using the Kanade-Lucas-Tomasi (KLT) tracking method. Homography-based image registration is used to align the measurements into the same coordinate frame, allowing for the detection of independently moving objects. The recently developed Recursive-RANSAC algorithm uses the visual measurements to estimate targets in clutter. Altitude-dependent tuning increases track continuity and coverage during the descent of the vehicle. The algorithm requires no operator interaction and increases the situation awareness of the unmanned aerial system. Real-time tracking efficiency is analyzed on GPUs and CPUs. Tracking results are presented and discussed using the MOTA and MOTP metrics.