If these prey items are on Stellwagen, the whales will eat them too. Down in the Caribbean the whales are not eating. The mothers spend their time nursing their young, while the other adults are busy mating. That's why they are so clear and the northern waters so murky. The whales usually feed enough in the northern waters to last them through their winter's fast.
Voluntary breathing is an important adaptation for whales.
They must constantly be aware of their location in the water. Since they are mammals and can drown if they flood their lungs with seawater, they must know when it's safe to take a breath. It is believed that the area around their blowholes is very sensitive and allows them to know when they have broken through the surface to the air. Voluntary breathing means that the whale must keep its brain active. Boats can often approach quite close at this time during whalewatching, and it is a time when animals can be in great danger from fast-moving boats unaware of their presence.