Even when more sea lions arrive,
they can't seem to break down the sardines' coordinated defences.
With a shoal this big, the sea lions need to isolate
a smaller, more manageable group of fish.
But with so few predators, the fish still have the advantage.
All the sea lions can do is keep the sardines at the surface..
and wait for others to join them.
Tuna.
Their arrival changes everything.
Tuna attack from below,
cutting off the sardines' escape route down to deeper water.
Next to appear, shearwaters,
excellent fliers, but also surprisingly agile underwater.
With so many predators attacking from all sides,
the advantage starts to shift away from the sardines.
As the fish pack ever tighter,
their shoaling strategy now makes it easier for the hunters.
Copper sharks.
They've scented blood in the water.
Surprisingly, perhaps, the predators never attack one another.
They work together to corral the ball of fish, taking turns to grab a mouthful.
Common dolphins.
As the shoal gets ever smaller,
each sardine scrambles desperately to hide in the middle.
But now there's no escape.
A Bryde's whale finishes off the feast.
Tons of sardines devoured in less than an hour.