The Golden Jaguar is the fourteenth treasure that can be found in Uncharted: Drake's Fortune.
The Golden Jaguar is found in Chapter 4 - Plane-wrecked. This treasure is in the next area (with pirates) after the previous treasure. After defeating the pirates, head left (opposite the next area with the large waterfall) and you'll see a huge white tree. The treasure is in the corner between the huge white tree and the small white trees.