Jeff,
You and your students may be interested in the occurrence of the Emperor Penguins you are observing near 75 S 150W. These adults are participating in the annual molt or the change over of their feathers. They leave the rookeries along the coast (western Ross Sea or Victoria Land) after the chicks have fledged and travel to where you are, and feeding heavily to increase their body weight. Once they start to molt, they have to stay on the pack ice because of the insulation loss and physiological stress of growing new feathers, so they lose about 40-50% of their body weight. They will be on the ice for a few weeks until about early February when they will feed again and migrate (over a 1000km) to the rookeries along the fast ice of the Victoria Land coast. During that time they will regain the lost weight, as they will start the breeding and birthing cycle again in the fall and winter periods (when they again go through an extended fast as shown in March of the Penguins, and lose a high fraction of their body weight keeping the egg warm (the males)). Look around on the ice as you go by these groups, you may see some dark spots where they are losing their feathers.
From our observations in this region in 2000, they tend to congregate on some of the larger floes with some ridging around which apparently are stable through the summer and provide some wind protection while they have to be out on the ice. Jerry Kooymann at Scripps has satellite tagged the birds leaving the rookeries and tracked their migration to this area as well as made the weight measurements at the beginning and end of the molt in this region.
Good luck on the rest of your trip,
Steve Ackley