Sun
It can peck at a rate of 16 times a second to drill holes in trees. It uses the holes for food storage and for nesting.
Moon
This Pokémon feeds on berries, whose leftover seeds become the ammunition for the attacks it fires off from its mouth.
Ultra Sun
It pecks at trees with its hard beak. You can get some idea of its mood or condition from the rhythm of its pecking.
Ultra Moon
It may look spindly, but its neck muscles are heavy-duty. It can peck at a tree 16 times per second!