Prerequisites: Terrenhuman that is psychic but only psychic enough to feel the presence of other psionics and not to be able to manifest powers. Most wranglers already have wild talent as the feat as a template ability.
A wrangler can detect psionics up to 120ft. radius but must make a will save equal to DC 10 + manifester level of the psionic presence or become sickened until out of range. Usually a wrangler knows that a psychic emanation exists when they begin feeling this type of ‘headache’. A psi-craft check is required to determine the exact power, manifester level, etc.
NOTE: If you also have telepathy, you can identify the nature of whoever left behind the power, such as their levels in psychic classes, alignment, and thoughts projected at the time via a neural imprint left behind. However, the DC for this Psicraft check is much higher (usually above 20).