The July cover shows a Eastern Rockhopper Penguin (Eudyptes chrysocome filholi) from the study Individual repeatability in laying behaviour does not support the migratory carry-over effect hypothesis of egg-size dimorphism in Eudyptes penguins.

You can read the paper here:

http://onlinelibrary.wiley.com/doi/10.1111/jav.00740/abstract

Photo by: Kyle W. Morrison

Download high resolution file: jab_47_04_cover-1.pdf