Raptor biologists have successfully used backpack-type harnesses to attach transmitters to a wide range of raptor species for research. As part of a graduate research project with Gray Hawks (Buteo plagiatus) in south Texas, we attached harnesses to 58 individuals and experienced problems with seven birds removing the harnesses and with all females covering the solar panels of the OrniTrack-10 GPS-GSM transmitters, preventing them from functioning properly. We appear to have resolved these issues by trimming nape feathers (short-term solution), switching to a different harness material, stitching through the knots, switching to a different brand of glue, and using a transmitter with an elevated solar panel for females, which are typically larger than males.