How birds avoid cactus spines

Did you ever wonder how birds like cactus wrens and curve-billed thrashers navigate cholla cactus without getting stuck? A couple of days ago I watched a curve-billed thrasher check out a cholla, probably seeking a good nesting site. Right after he landed on the end of a cholla segment, but before walking in and out of the cactus’ depths, he first folded his wings in an X in the back, making himself much slimmer. I plan to watch closely to see if cactus wrens do this too!
NOTE: I did not take the above picture, and don’t know who did. But wish I had.