Squirrel #13: Swamp Crash
At the start of the track, reverse into the tree behind you to make it fall over.
Now complete a faultless run until you cross over the floating log, then bailout at the next jump to land on the raft below.
The raft will then float out to reveal the next squirrel.
Squirrel #14: Temple Trouble
This is a tough one! At the start of the track, drive to the top of the ramp ahead then roll backwards and use your momentum to reverse bunny hop up to the first switch. There are six more switches to activate and you'll need to hit them all on a faultless run or they'll disappear.
Now ride up the first ramp and land on top of the platform to trigger switch number two.
Continue down the track until you clear another high wall and drop down, then slowly roll up to the third switch at the end of the next platform.
Reverse back along the same platform to find switch number four has appeared.
Jump to the next scaffolding section then slowly approach the top of the ramp for the fifth switch.
After passing the short dirt section with a circular door behind it, jump the ramp at the end to hit switch number six but don't go over the lip of this platform.
Instead, roll backwards off the platform to land back on the dirt track and trigger the seventh and final switch, revealing the squirrel.