I've been thinking about this behavior, wondering why it is happening and what the Humpbacks derive from doing it. Some have postulated that the Humpbacks are "getting even" with Orcas who kill Humpback calves. I'm not sure about that but it does seem plausible. The Humpbacks don't gain anything by protecting seals. Its possible the two even compete for the same food, so one would think one less seal would benefit the big whales. Still they interfere, lobbing their huge tails and enormous flippers at the Orcas, ramming them head on when possible and putting themselves between the Orcas and the ice floe where seals would otherwise be easily swept into the water and picked off by the black and white predators. Maybe whales are far more complicated than we ever imagined.
Humans like to think we are the only species given to certain emotions like love and friendship. People reveal their amazement when learning a dolphin continued to protect its dead calf for days after the death, a gorilla carried her baby's limp body for weeks, and elephants cry at the passing of one of the herd. We like to think altruism- or practicing acts of detached selflessness for the benefit of others, is a characteristic unique to humans. The animals we share the planet with are showing us over and over this is just not the case.
When Hal Whitehead wrote The Cultural Lives of Whales and Dolphins, scientists in other disciplines had (and still have) a hard time accepting that the behavior Whitehead witnessed and studied was indeed culture. That Whitehead saw culture firsthand as Humpbacks experimented with new songs, learned them, sang them and then taught them to other whales did not necessarily satisfy some in the science community that whales were transmitting elements of culture. Neither did accounts of a formerly captive dolphin who, during his captivity, had been taught tricks that he later taught to his native pod upon his release back into the wild population. The trick he had been taught was behavior not seen in wild dolphins- the ability to rise up out of the water and travel backwards on the tail. The behavior has no useful purpose to dolphins, but they learned it from each other regardless and incorporated it into their social structure. Dolphins that could do it seemed to have higher rank than those who could not. If we cannot accept the concept that animals have culture, we are going to be less likely to accept they have complex emotions, and operate as emotional beings and not merely from instinct. And we are certainly unlikely to accept that whales can be altruistic.
But the photos speak. It is right there, waiting to be accepted. A photo of Wendell seal tucked under the flipper of a Humpback whale, and not by accident either. The whale was observed scooping this seal up and shielding it from the Orca. Maybe this new knowledge gives us greater responsibility, as when we accepted that humans of different races are humans nonetheless, and entitled to good lives of their own making. Maybe its time, finally, for us to consider the altruism of humpback whales.