You can perceive the world by creating high-pitched noises and listening to their echoes. This gives you blindsight to a range of 40 feet. The echo-producing noises are too high-pitched to be heard by most creatures, and can only be detected by dragons, other creatures with this ability (such as bats), and creatures with hearing-based blindsense or blindsight. You cannot use this ability if you are deaf, and cannot detect anything in an area of silence.
Pathfinder Roleplaying Game Ultimate Magic. © 2011, Paizo Publishing, LLC; Authors: Jason Bulmahn, Tim Hitchcock, Colin McComb, Rob McCreary, Jason Nelson, Stephen Radney-MacFarland, Sean K Reynolds, Owen K.C. Stephens, and Russ Taylor.