William Gilly has seen a Kraken. The mythical squid beast with
ship-dooming tentacles surely exists, Gilly says, because he's seen
a baby one. "It was this big around," he says, making a circle as
big as a tire with his arms, a proud, boyish smile on his face.
Fishermen spotted the carcass of the 2.4-metre-long, 181-kilogram
baby giant squid in Monterey Bay three years ago, according to
"If you're an assistant professor proposing to study it, I don't
think you'd get tenure," he says. "But one has to exist."
laboratory at Stanford University's Hopkins Marine Station
in Pacific Grove brims with squid décor: stuffed animals, preserved
specimens, glass figurines, drawings, photographs, plastic toys,
and piñatas. He has studied these denizens of the sea for almost
four decades, and he's handled countless numbers of the fabled
Kraken's smaller cousins, the very real jumbo Humboldt squid. Like
their giant counterparts, Humboldt squid are enigmatic. No one has
seen them mate or lay eggs. No one has watched them develop from
egg to adult. No one knows how many exist.
These tentacled titans have now ensnared marine biologists with
another riddle: they have left their normal gathering grounds in
the Sea of Cortez in Baja California, Mexico. Fishermen worry that
a critical part of their livelihood may be gone. Many families have
depended on Humboldt squid since the slippery creatures moved in
droves into the Gulf of California's Guaymas Basin in the
"We have a huge problem on our hands," says coordinator Juan
Pedro Vela Arreola of the Alianza de Ribereños y
Armadores, an association of fishermen and producers in Mexico.
"Fishermen are desperate."
Gilly blames the most recent El Niño in the Pacific Ocean for
forcing some Humboldt squid to migrate away. Others have physically
shrunk -- just one bizarre adaptation among their many strange
body-shifting traits. Leaders of Mexican fisheries and scientists
are banding together to figure out whether the diablos
rojos (red devils) will come back, and how to cope in the
"You have to learn to live in a very unpredictable way," says
Unai Markaida of El Colegio de la Frontera Sur (ECOSUR)
in Campeche, Mexico. "You live like a squid, and you adapt to the
life it leads."
"They're very mysterious," says marine biologist Danna Staaf,
stressing very in a slightly higher pitch. "And
Staaf, a self-described "cephalopodiatrist,"
completed her PhD with Gilly's team. She studied Humboldt squid on
two summer research cruises in the Gulf of California before the
latest El Niño drove them away. She and her crewmates pulled up to
15 squid out of the water every night, when they would come up to
the surface from depths of more than 975 metres to feed. Many of
the 9-kilogram cephalopods she caught were about 1.2 metres long.
Most were a year old. Scientists can tell their age by looking at
the number of rings on tiny crystals located near their brain
called statoliths, like botanists can age a tree by counting its
rings. These stones help a squid detect gravity and maintain their
balance and sense of space.
The scientists stored some of the catch in their "squid condo,"
an oversize cooler with continuously flowing water and six clear,
plastic tubes. They housed squid in separate tubes to keep them
from attacking one another. Over the next few days, they studied
the squids' behaviours and neurophysiology. For instance, altering
the temperature and oxygen content of the water could trigger or
change their escape response -- the way squid dart away when
startled by a predator.
Staaf dissected other squid to study their development, the
focus of her dissertation. She used their eggs and sperm to make
squid babies. She wanted to discover the temperature range at which
their eggs could hatch and develop. At the time, Humboldt squid had
spread to waters off the coast of Monterey. Marine scientists
thought the squid might establish new colonies there, but Staaf
wanted to know whether it was even possible for the animals to grow
in the much cooler waters of California's Pacific coast. In the
lab, she found, their
eggs can grow between temperatures of 15 and 25 degrees
Celsius, suggesting it is possible they could set up a breeding
population. Whether squid babies have the same preferences in the
wild is still unknown, Staaf says.
Other team members studied squid chromatophores, structures in
their muscles that allow them to change colour. Humboldts sometimes
flash from red to white as they propel themselves through dark
waters. Scientists don't know how they control these colour shifts,
whether it's the brain or local nerve cells that set off the
flickering. They also don't fully understand why they suddenly
change colours, but some speculate it's a form of
When they're not in direct contact with other squid, their flesh
flickers from red to white in a random, mosaic-like pattern. Gilly
compares this to visual white noise. But as they interact with
their species, the irregular colour waves become more organised,
like a cephalopod Morse code, Gilly says. They can change the
intensity of the flashing, as well as the rhythm and frequency.
Squid might use these "calls," together with arm posturing, to
attract mates or to establish hierarchies, for example.
Gilly and his team have seen some of these behaviours through
underwater "Crittercams," about
the size of 340-gram drink bottle, attached to a squid's back.
"Ideally, we'd also like to see what they eat," Gilly says, because
that might help his team study these animals. Scientists can't get
Humboldts to eat in the lab, so squid last only a few days in
Indeed, squid dislike being trapped, strongly. Sometimes they
get so anxious, they ram themselves against the tank. "They've
never seen the bottom. They've certainly never seen the wall of a
tank," Gilly says. "They're intelligent organisms. And when you put
one in an abnormal situation, they get totally freaked out. They
don't do their flickering in the lab," he notes.
Scientists do know that during the day, Humboldt squid forage
for silvery lanternfish and other small animals in the oxygen
minimum zone, a dark, cold netherworld more than 900 metres deep.
Here, oxygen is scarce, and while few animals can withstand its
hostile environment, Humboldts seem to thrive. "Living in low
oxygen -- that's surprising, especially for an animal that's an
athlete," Markaida says. How they move and how their nervous system
functions under these conditions is still a mystery.
Widespread changes in the temperatures of Earth's oceans have
compelled many creatures, including the powerful Humboldt squid, to
seek new climes. Their dominion usually stretches from Argentina to
California, but more recently they've been spotted in Canada and
Alaska. Scientists don't yet understand how the squid are settling
into their new hangouts. This month, a few Humboldts stranded
themselves on the beaches of Pacific Grove, Calif, while
whale-watching boats have spotted them near Point Pinos. These
sightings might be a sign they are returning, Gilly says.