 New
Year’s Eve, and the clock was just about to
strike midnight. In the streets and bars of San
Diego’s famed La Jolla district, bands were
blaring, bodies were gyrating and the
party-goers were feeling no pain. But the
terrestrial celebrations were rather tame
compared to the orgies and feasts taking place
in the waters immediately off the beach at La
Jolla Shores, roughly a mile away. Literally
millions of squid had invaded the La Jolla
Submarine Canyon. With them had come a host of
hungry predators and scavengers intent upon
feeding on the squid.
Photo Op
For an underwater photographer and filmmaker, it
is difficult to ask for a better opportunity to film
animal behavior and natural history. As a rule,
wildlife photographers, especially those of us who
work underwater, are constantly racking our brains
trying to figure out ways to get close to animals in
order to film them well. But with the squid, the
dilemma was that there were so many, I was finding
it almost impossible to frame up a good shot. I
couldn’t even clear my mask or grab my regulator
without simultaneously grabbing a handful of rubbery
squid. There were squid around our heads, between
the second stage of our regulators and chins, under
our armpits, between our legs and under our fins. My
assistant, Mark Thurlow, later told me that he felt
like we were diving in a swimming pool
three-quarters of the way full of some kind of
jiggling pasta.
Wild Scene
Groups of squid were mating everywhere we
looked, and squid egg casings already obscured the
sand bottom. Furthermore, a variety of fishes and
other animals including bat rays, thornback rays,
sheep crabs and sea lions were feeding on the squid.
Talk about a wild scene.
Of course, there were scenes like the one we
were witnessing all over Southern California that
night, as the La Jolla Submarine Canyon is only one
of any number of sites where market squid gather to
mate during typical Southern California winters.
Also known as common squid, these cephalopods
usually inhabit deep water, but they mate and lay
their eggs in much shallower surroundings. The
mating and egg laying typically occur over sandy
bottoms, sometimes at depths as shallow as 30 to 40
feet/9 to 12 m, but more commonly in slightly
deeper, cooler water. The event is often referred to
as a “run,” and during heavy runs, which can last
for several weeks or even months, literally millions
of squid gather to mate in coastal canyons and along
steep sand drop-offs at the offshore Channel
Islands.
The instinct to mate among market squid is
incredibly strong, and the males appear frantic as
they attempt to embrace a female. Market squid are
only believed to live for one year, just long enough
to reach sexual maturity, mate and die. It is quite
common to see three, four or more males all
clutching the same female in an undersea orgy.
Squid are capable of swimming forward, backward
and sideways with near equal rapidity,
jet-propelling themselves with a directable siphon
and undulating tail fins as they seek out a mate.
When mating, squid often change colors rapidly as
they pulsate from creamy white to deep purple to
brown and green. The color changes are believed to
express excitement and communicate with other squid.
Often when a male is successful in his efforts to
grab onto a female, his tentacles instantly blush a
scarlet warning to deter other males from attempting
to woo his mate. In an effort to ensure that he
perpetuates his own genetic code, a mating male
quickly and adeptly passes a packet of sperm
underneath the mantle of the female. Soon afterwards
she will use the sperm to fertilize her eggs.
After mating, the females plant a single egg
casing in the sand. The whitish 8- to 12-inch-/21-
to 31-cm-long egg casing contains approximately 200
eggs. It is estimated that only a few will live long
enough to reproduce. While each female plants a
single egg casing, the sheer number of egg casings
transforms the once-brown bottom into a shag carpet
of egg casings. Five to seven days after an egg
casing is planted, you can see the bright-red eyes
of the unhatched embryonic squid inside. In another
week or so the eggs will hatch, and the newborns
will instinctively head for deep water. One year
later, those that manage to survive will take part
in the mating ritual.
Shortly after mating, the captivating color
shows slow and cease as the adult squid weaken,
taking on a sickly, pallid hue. Their sucker-lined
tentacles soon become grossly disfigured, and their
bodies show signs of marked deterioration. With
their life cycle complete after only a year, death
is not far away.
The Morning After
Within a time span of a few hours to a few days
after heightened mating activity, the sea floor
becomes covered with piles of dead and dying squid.
The squids’ weakened state makes them easy prey for
a wide variety of scavengers and predators who are
quick to take advantage of the opportunity to gorge
themselves. Often bat rays, horn sharks and angel
sharks devour so many squid that they end up
immobilized on the sea floor with pieces of
partially eaten squid dangling from their mouths. It
is a scene reminiscent of the need to get to the
closest couch after a Thanksgiving Day feast when
you are stuffed full of turkey and stuffing.
As a general rule, bat rays are somewhat wary of
divers, but during squid runs it is not uncommon for
these rays to swim, rest and feed within touching
distance of divers.
Rockfish, black seabass, cabezon, sculpin and
myriad other fishes often join the fray. Lobster and
crabs leave the protective confines of nearby reefs
to forage out in the open on the dead and dying
adult squid.
High up in the water column sea lions, harbor
seals, pilot whales and blue sharks prey upon the
concentrations of still-living adult squid. Blue
sharks rarely come so close to shore, but the
presence of so much easy-to-catch food is sometimes
too much to resist. On the surface, flocks of sea
gulls, pelicans and other seabirds gather to feed.
The great concentrations of seabirds, sea lions,
seals and occasional pilot whales at the surface are
a sure sign of the activity below.
Even with so many hungry mouths to feed, the
squid often die off in such huge numbers that in
places they become stacked one on top of the other
in piles that are 2 feet/.6 m thick. Interestingly,
the seemingly vulnerable egg cases are not heavily
preyed upon. Some specialists suspect that this is
due to the presence of proteins that prove repulsive
to potential predators. However, once they hatch,
newborn squid become fair game for a wide variety of
predators.
Hatchling squid are sought after by a variety of
crustaceans, fishes, seabirds and marine mammals. In
fact, life is so difficult for squid, specialists
estimate that from the average egg casing, which
contains approximately 200 squid eggs, only a
half-dozen or fewer will survive for one year, when
they will attempt to mate before they, too, perish.
Many of the species that prey upon the squid,
such as blue sharks and pilot whales, are highly
migratory, so there is little question that common
squid play a vital role in marine ecosystems in many
oceans, in addition to local waters in Southern
California.
Because of the importance of the squid, some
specialists are very concerned about what appears to
be declining numbers in market squid. Common squid
are commercially fished as a food source and for
biological studies due to their highly developed
optic nerves, which makes them ideal for research
and teaching. In recent years the take has been
alarmingly low in many areas that had been very
productive in the not-too-distant past. It is
difficult to say with absolute certainty whether the
reduced catch is part of a natural cycle, a result
of the recent El Niño or due to overfishing.
Fisheries specialists will be keeping a close eye on
the matter during upcoming seasons.
Diving the Squid Run
When the squid do mate at depths that are safely
accessible to sport divers, it is generally during
the middle of winter. However, I have witnessed a
heavy run in August in San Diego during the
mid-1970s. Whenever a run occurs, it is a wonderful
time to dive as long as conditions allow. The squid
are driven by strong instincts as they search for
willing partners, and they pay little attention to
outsiders, whether potential predators or underwater
photographers, so getting close is not a problem.
Sometimes the activity is hot and heavy during
the day, but as a rule it is much more intense at
night. If you do have the opportunity to night dive
with the squid, it is wise to become familiar with
the dive site during daylight. As a rule, there are
far more squid around at night, and dive lights
often prove to be squid magnets. At times I have
been surrounded by so many squid that I could not
see my fins, gauges or dive buddy. The concentration
quickly dissipated when I turned my light off or
covered the beam for a moment, but it can be rather
disorienting to be surrounded by a dense cloud of
swirling squid. That feeling is heightened
considerably if a sea lion or bat ray — or
occasionally, a small shark — suddenly pokes its
head into view. Make sure you are mentally prepared
for such close encounters.
In addition, in many places such as San Diego’s
La Jolla Canyon and in a variety of sites at the
Channel Islands where divers enjoy the squid runs,
the bottom is a bit deep and drops away quickly, so
be sure to monitor your depth gauge. As with any
night dive, it is wise to do what you can to make
sure you know the area well before making a night
dive with the squid.
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