Key Takeaways About Baby Squids
Some baby squids look like tiny adults from the moment they hatch.
Depending on the species, some baby squids grow rapidly. Some can even go from hatchling to near-adult in a few hours to a few days.
Some squids have a short lifespan, so they've developed specific maneuvers to avoid becoming prey, such as deploying ink and using camouflage. Baby squids have not yet developed this, making them more vulnerable to predators.
Parents often lament how children grow up too quickly. One day, their kid is posing for a picture before their first day of kindergarten. A few blinks later, and they are sitting for their senior class portrait.
Childhood may seem to fly by for humans. But for some marine life, certain stages of immaturity speed past in a matter of days. Depending on the species, a new hatchling may be on the verge of adulthood within mere hours.
In captivity, baby squid (known as paralarvae) have shown scientists just how quickly they grow up.
Read More: How the Squid Eye Mastered Sight in the Deep Ocean Through Evolution
Baby Squids Often Look Like Tiny Adults
At the Monterey Bay Aquarium, an exhibit gave aquarists a glimpse at the early lives of baby squid. The Bigfin Reef Squid (Sepioteuthis lessoniana) looked like a little version of adults as soon as they hatched.
“They had a mantle, arms, eyes, and exhibited schooling behavior despite being only five millimeters long,” says Catherine Traub, a senior aquarist at the Monterey Bay Aquarium.
Unlike other marine life, many species of squid don’t go through a major metamorphosis, and their physical changes can seem less pronounced.
“It is variable depending on the species, but very generally they will look like small versions of the adults and live in the water column,” Traub says.
Baby Squids Can Grow Really Fast
In addition to looking like adults, Traub says the Bigfin Reef Squid in their exhibit were also quick to act like adults. “They were even big enough to start eating small mysid shrimp within a few days of hatching. It was quite amazing to see a tiny squid display feeding and hunting behavior,” she says.
The length of the paralarval stage depends on the species, and there are more than 300 species of squid.
For species like Sepioloida and Idiosepiidae, opportunities for baby pictures may be limited to mere hours or a few short days. But some colder water species can take several months to advance out of the paralarval stage.
For the Bigfin Reef squid living at the Monterey Bay Aquarium, the short road to maturity was likely due to the species’ lifespan.
“They are a shallow-water species from the Indian and western Pacific Ocean. They are quick-lived and grow very fast, living just over a year with some reaching over a foot long,” Traub says.
Part of their short life also includes courting and egg-laying. It’s one of the reasons why aquarists like Traub say they are fascinating marine animals to study. “They live quick lives going from hatching to dying in (mostly) less than a year— it is hard to grasp the timeline of their lives,” she says.
How Baby Squids Combat Predators
In addition to a short lifespan, baby squid have another motivation to grow up — predators. Birds, fish, and marine mammals are all potential threats. Even other cephalopods will prey upon paralarvae.
Paralarvae may resemble adults, but they have yet to develop their speed, and their size makes them vulnerable, especially because scientists have observed that paralarvae don’t employ the protective behaviors used by adults. Some squids will use camouflage or escape behaviors. Others will use inking to get predators to back off. But paralarvae are still in a learning phase, which makes them vulnerable.
Such fragility makes squid babies interesting to study and observe.
“What is striking is the combination of strength and vulnerability — seeing how tiny they are when they hatch out, imagining how they live and survive out in the wild that small,” Traub says. “But then, when I throw shrimp into the tank, I see how fierce they are when they are feeding and hunting, even at five millimeters long.”
Read More: Once Thought Mythical, Colossal Squid Spotted Alive for the First Time
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
Frontiers in Marine Science. Cephalopod ontogeny and life cycle patterns
Journal of Experimental Marine Biology and Ecology. Anti-predator behavior of squid throughout ontogeny
Emilie Lucchesi has written for some of the country's largest newspapers, including The New York Times, Chicago Tribune and Los Angeles Times. She holds a bachelor's degree in journalism from the University of Missouri and an MA from DePaul University. She also holds a Ph.D. in communication from the University of Illinois-Chicago with an emphasis on media framing, message construction and stigma communication. Emilie has authored three nonfiction books. Her third, A Light in the Dark: Surviving More Than Ted Bundy, releases October 3, 2023, from Chicago Review Press and is co-authored with survivor Kathy Kleiner Rubin.
