Diving into squid territory
Jumbo squids invaded Orange County late last month. The 10-limbed creatures, weighing up to 60 pounds, swarmed the waters near Newport Beach, and anglers delighted at the prospect of calamari steaks.
Bruce Robison, senior scientist at the Monterey Bay Aquarium Research Institute, talked about the life of squids and why we shouldn’t be afraid of these marine cephalopods.
Why did this invasion happen in Orange County?
There has been a large-scale invasion of the entire California coast that started in 2002. We see peaks of squid in different places at different times, but these are probably just local events.
In 2002, the population of jumbo squid [also known as Humboldt squid] expanded north, up the California coast. In Central California, the squid used to show up chiefly during the El Niño periods. When El Niño was gone, so were the squid. But in 2002, they moved in and they’ve been here ever since.
Their home range is the eastern tropical Pacific. In the waters around their home range, they competed for food with tuna, sharks and others. But through fishing, we have taken out 90% of the big fishes that compete with the squid for food sources. So there has been a lot more food available for the squid. Also, those big fish fed on baby squid, so the predation has decreased. Naturally, with those changes, population and home range are going to expand.
The ocean’s also gotten warmer, which has made it easier for them to move into other areas.
What are the consequences of this movement?
They have a new impact. For example, a type of fish called hake has plummeted in population. Hake are an important commercial species off the West Coast.
From examining stomach contents, we know the squid are eating the hake. The hake population tanked, and it looks like it is going to stay that way. So the question becomes, what will the squid eat next?
Are the squids any danger to swimmers or fishermen?
No. I don’t know of any legitimate stories of any humans being damaged.
How long do they live?
All squid have really short life spans. A full-grown Humboldt squid lives two years, max. Lives fast, dies young.
Are they native to Pacific waters close to shore or do they typically stay down deeper?
Squid go where there is food to eat or where conditions are best. This month conditions might be nice in Newport, next month it might be Malibu. They are in Newport now because it just may be that there is more food there right now.
Are squids intelligent?
It’s hard to gauge, but we think they are relatively intelligent from what we know about octopuses -- a very close relative. Octopuses can learn and they adjust their behavior based on what has happened in the past.
How big can squids get?
We used to think that Architeuthis was the biggest squid. It may grow to lengths as long as 50 feet. But another squid which was recently discovered -- the colossal squid -- it might be even bigger than that. The main body of a colossal squid is very big -- maybe twice the size of an average human.
Jumbo squid -- a really big one is probably as long and tall as you are. In length, 2 meters [about 6.5 feet] total. About 1 meter for mantle length.
Smaller ones, market or calamari squid -- the whole length is 6 inches.
How do they defend themselves from predators?
Let’s say there’s a big swordfish coming; the squid can squirt a cloud of ink and swim away in the other direction because the swordfish can’t see through the ink cloud.
But they have other ways of protecting themselves. Some of their suckers, along their arms, are sharp. The squid would wrap its arms around the swordfish and stick it. The suckers are primarily for holding prey, but they can be used against predators.
They also have a beak, much like a bird’s beak -- that’s its mouth, what it eats with. But it can also use the beak against predators.
What fascinates you about these creatures?
They’re big and they’re fast and they can change color. They can create patterns on their bodies. They can make circles, spots, stripes.
The Humboldt squid are real masters at signaling back and forth this way. They are constantly talking to each other using displays of colors and patterns on their bodies.
We know that’s what they are doing, but what we don’t know is what it means. It is an alien communication that we’d love to understand.