These predators don't look like a menacing mob.
Humpbacks are known as the ocean's gentle giants.
Tell that to its prey.
The humpbacks are setting the stage for a massacre.
Humpbacks can look gentle—as watching a mother with calf proves.
They feed mainly in summer and live off their fat in winter.
Their commute to their feeding ground is the longest known migration of any mammal...up to 10,000 miles round trip.
Humpbacks are generally loners. But they'll come together to hunt.
Southeast Alaska. These humpbacks are about to net thousands of fish.
They use two tactics that in the hands of a child would be harmless: singing and blowing bubbles.
But with humpbacks, the combination is lethal.
On one side of the shoal of fish, one whale creates a wall of bubbles.
On the opposite side of the shoal, another whale sounds the battle cry.
The famous song of the humpback...except now, the song becomes a dirge.
One hundred and eighty decibels...equal to a rocket launch and powerful enough to damage human ears.
The fish flee from the uproar-and collide with the wall of bubbles. They see the bubbles as a barrier.
While they're blocked, the blower swims around them...surrounding them in a bubbly prison.
With no other way out, they head for the surface to escape...right where the whale wants them.
In this ring of death, dozens of humpbacks will feast.
They have no teeth—so they swallow their prey whole.
And if any creature should be nicknamed "Jaws," it's the humpback.
It can spread its jaws more than 13 feet wide and swallow hundreds of fish in one gulp.
Its throat and chest are lined with 30 wide, ventral grooves-allowing it to open its mouth as wide as possible, to take in hundreds of gallons of water, swimming with prey.
They may eat like this twice a day, during the feeding season.