After finding a few dead Blue penguins washed up on a beach and examining them, I have noticed that two of the skulls easily fit onto my index and middle finger’s, but the third was the size of my palm. I can confirm these were all LB penguins as there were other bird nerds in my group and all there were found with a full body. The two smaller skulled specimens had full blue adult plumage, and the bigger looked very brown (a light brown). We also think the bigger skulled one might be the white-flippered penguin subspecies if that is any help.
I am just a big curious as to why the skulls are such vastly different sizes for the same species.