Netting.

[ranit]

Ours is 8 ft. on the sides with 14 ft. PVC poles in the middle raising it up. We cut knotches in the PVC to help hold the netting in place.

 

[MinxFox]

We have a birdhouse that is 15ft. tall in the center of the pen that holds it up the highest, and the other supports are 10ft. or higher then the fence is 8ft. tall.

 

[Chicken0Boy]

 

[patti'speeps]

We use coffee cans on top of all our posts that hold the flight nets up. It works really well. We had issues with severe ice storm this winter though. With the amount of ice we had I don't think any netting would have held up.