As soon as you enter this portal, you’ll see a birdseed holder. Go ahead and take several handfuls of birdseed, at least six or seven.
Head west a little ways and your path will be blocked by a bird next to a bird feeder. Back up a few steps and travel south until you see another bird feeder next to a track on the ground that is directly south of that bird. Use some birdseed in that bird feeder. Adding birdseed to the feeders attracts the birds. In this case, the gate blocks the path of the bird to the north, so it will return to its original position. However, a bird from the west will be attracted to the feeder and stay there.
Head west in the direction that bird came from. Then travel a bit north and you’ll see a lever on the other side of the track on the ground. Pull down that lever and a nearby gate will close.
Return to the direction from whence you came and note that the gate that had blocked the one bird before is now gone. Leave that area alone and keep going a little north of that original bird until you see a passage to the west. Just inside this western passage is a lever in a southern alcove. Pull down that lever.
Now, head back south through the main tunnel in this area until you see an eastern path just south of the entrance to the area. Make your way to the southeastern part of the area and you’ll see another lever in the southeast corner with a bird blocking its path. Put some birdseed in the feeder just west of this bird to draw it away from the area it is blocking. When you try to run around to get to this lever, you’ll find that another bird is still blocking the path. Perform the same trick of using the birdseed on the feeder to get this bird to move as well.
You should now be able to get to the lever in the southeast corner. Make your way over and pull down this lever.
Now, head back to the lever you pulled immediately prior to this one (the one just northeast of the entrance to the tunnel in the southern alcove. Move this lever again – this time, you are pushing it up.
Walk just a couple steps north and use another handful of birdseed on the feeder directly to the north of this lever.
This will open up a path to the lever in the northeast area of the tunnel. Head in that direction and pull that lever down.
Return to the southwest corner of the tunnels to the feeder that is close to the first lever you pulled. Use the birdseed on that feeder to return that bird to its original position.
Go back to the very first feeder you placed birdseed in. Use the birdseed on this feeder again. Since the gate has been opened on that north-south track, the bird from the north will be drawn to that area and stay.
Now, the path to the pedestal that holds the golden feather (directly west from the birdseed holder) is completely unblocked so you can go there and pick up the feather.
After you get the feather, return to the main part of the tunnels.