Levitating Leviathans
The tail end of our latest oceanic low failed to dampen our enthusiasm with its occasional shower. Bright sunny periods lit up the incredible landscape of distant snowy mountains, dark, tree-clad lower slopes and fjords, inlets and channels. A call from the bridge announcing a congregation of whales up ahead brought all the guests up on deck, from where we witnessed one of the best whale shows ever. A group of no fewer than ten humpbacks were foraging cooperatively, utilizing a method known as "bubble net feeding".
The strategy is amazingly complex, in that it often involves up to a dozen humpbacks closely cooperating under the supervision of one mature individual, usually an older female. All the participating whales dive in quick succession, something we had no trouble observing from the Sea Bird, and then, while we waited anxiously, not being able to see what was happening under the surface, the whales performed an intricately choreographed feat of synchronized swimming. Whale researchers have now discovered what goes on during the three to four minutes that the whales are underwater. Blowing streams of air out of their blowholes, some of the humpbacks create a circular net of rising bubbles, into which other members of the team drive the school of confused herring, which is the target of the exercise. Then, when the tightly packed school is near the surface, the whales rush upwards, and opening their mouths wide at the right moment, they break the surface while gulping up as much herring-containing seawater as their expanded mouths and throats can hold. That sudden last part of the performance was very much visible to all of us on the deck of the Sea Bird. To exclamations of 'there!' and 'wow!', and to the clicking sound of camera shutters, levels of excitement surged to new heights.
After a few repeat performances we noticed the whales becoming less coordinated, and after one more dive they resurfaced not in their tight cluster, but scattered over a larger area, and then, for no reason known to science, first one and then another breached. This well-described, but always thrilling, sight of a forty ton animal levitating out of the depths, up towards the sky, carrying a rush of water with it, twisting its body, with its twelve foot long pectoral flippers reaching outwards, has to be one of the greatest wildlife experiences of all. For a fraction of a second, the humpback seemed to hang there, motionless at the top of its leap, then it crashed back into the watery element its ancestors had chosen for all their descendants.
There are a number of untested scientific theories that may explain this amazing behavior of whales, but if, like us, they have individual personalities, one would think that after a particularly good feeding bout, some of them would breach simply out of pure joy.
