After a little over 30 miles (30.25 or so) you will enter Whistling Bird  you will see a huge rock that has broken from the cliff face into the river.  The river runs on both sides of the this massive rock the right side leads to an under cut cave.  If you have not run Whistling Bird before there is an easy scout on the left side.  The debris on the left tends to push you right at medium water and is shallow.  The run next to the rock looks scary but really isn't too bad, and at medium to low water this is where you will likely wind up. Don't be tempted to run this too conservatively and crab an oar in the shallow water. At higher water run it to the left. 

There is a debris field on the left pull in and walk to see the entry if you have not run it before.  It is a very easy scout.