You'll need to use the lake to help you get there. Have Wolfy jump in the lake to see what happens.
Those eyes might do odd things if they were irritated.
Try dropping a grain of sand in the lake to see what happens. You can get one from the Window of Memory (see another hint to figure out how to use it).
The fish in the bubble will be able to take you to the decoy if both you and Wolfy cooperate.