Today I filled in the penguins, I haven't gone into too much detail, I'm not sure I will. I need to make a few areas stand out a little more, and play with some highlights. There are also some rosy hues reflecting off the white areas such as their tummies.
The sea I've played with a dry bristle brush to re-expose my original background colour. I also tried wetting the pastel, but was a little concerned I would get tide-marks as it dried. The penguin on the far right, I need to tweak his arm, its going to close to the edge of the paper.