Zarcillos in Ballestas

After sad news on Paracas, I decided to keep posting about what I found there months ago, hopefully these guys are still around...

This bird is called "zarcillo" (zarcillo means earing, locals say that they named it like that because of the line on the side of the head, which simulates an earing), the scientific name is Larosterna Inca. I haven't found much information on this one, so, it would be great if someone could help me complete this information (come on Shaun! give me a hand! hahaha)
They are brownish or grey when they are young and have red beaks and feet, along with a yellow carnosity under the beak. They live along the coasts of Peru and northern Chile.
It's a beautiful bird to watch, specially in the caves of the Ballestas Islands.