How many of us get a rash from poison ivy? (Raise your hands.)
It looks like the vast majority of us are allergic to it while some are not sure.
I know only one person who's immune to poison ivy. The rest of us get a rash, mild to severe, or avoid the plant so carefully that we haven't tested the limits recently.
Birds are not only immune to poison ivy's itchy oils -- they eat its berries.
Here, a migrating yellow-rumped warbler (Setophaga coronata) inspects a cluster of poison ivy berries, and then he swallows one.
It makes my throat itch to think about it.
(photos by Cris Hamilton)
p.s. Notice this warbler's wide field of vision. In the first photo you can see both of his eyes from the top of his head.