The visual effect contributed to their frightening reputation, but scientists have also investigated these changing patterns as a form of signaling.
Cranston did not stay safely on the boat to observe it.
He went down.
The First Squid Came Close
Once underwater, Cranston found himself surrounded by animals that were fast enough to appear suddenly and strong enough to physically move a diver.
He later described Humboldt squid approaching and grabbing him with their arms, apparently testing his resistance.
A mature squid, he said, could pull a diver around considerably.
The disturbing part was what happened next.
According to Cranston, if he resisted, the squid would often retreat.
That behavior complicated the easy story of a mindless predator attacking a human.
The squid seemed to be investigating.
They would approach.
Make contact.
Pull.
And react to his response.
For a cameraman trying to document an animal few people had observed closely underwater, it was extraordinary.
For the person inside the diving suit, it also meant that the boundary between observation and physical confrontation could disappear in seconds.
A shark might pass through the edge of visibility.
A Humboldt squid could come directly toward the camera.
And there might not be only one.
Then Cranston Changed the Lights
One of Cranston’s encounters illustrates how quickly conditions could change.
Ordinary underwater filming lights created a bright zone around him. Documentary footage later described the illumination as something of a barrier: the squid remained outside the brightest area.
Cranston wanted them closer.
So he experimented with red illumination, which dissipated differently underwater.
It worked.
Perhaps too well.
The squid approached far more closely. Documentary footage of the encounter shows them moving toward Cranston with little apparent fear, closing the distance until the cameraman was surrounded by fast-moving animals in the darkness.
The experience was intense enough that the documentary characterized it as a close call.
Cranston’s response afterward was revealing.
Rather than deciding never to return, he became more interested in the squid.
Something about their behavior did not fit the simplistic image of an underwater killing machine.
The closer he got, the more questions appeared.
Imagine Being Suspended Above an Abyss
Part of what makes these encounters so unnerving has little to do with the squid themselves.
It is the environment.
At night in deep open water, a diver’s usable world can shrink to the reach of a light.
Beyond that illuminated space is almost nothing.
No horizon.
No recognizable landscape.
Sometimes no visible bottom.
Depth becomes difficult to perceive visually. A diver must depend on instruments, training and awareness of position.
Now place large, rapidly moving animals inside that environment.
A squid can disappear beyond the light and return from another direction.
Several can arrive simultaneously.
Their bodies can change color.
Their arms can reach outward immediately before contact.
And unlike a human swimmer, Humboldt squid are completely at home in the vertical dimension of the ocean.