Article image

New species of deep-sea squid discovered that broods giant eggs

The deep sea, a realm of eternal darkness and immense pressure, remains one of Earth’s greatest mysteries. It’s a place where life has adapted in extraordinary ways, and where new discoveries are made with each exploration.

One such discovery, made by the Monterey Bay Aquarium Research Institute (MBARI) in 2015, has recently come to light, shedding new insights into the eggs and reproductive behavior of deep-sea squids.

Mother’s sacrifice in the depths

In the murky depths of Mexico’s Gulf of California, MBARI’s remotely operated vehicle (ROV), Doc Ricketts, captured a remarkable sight: a mother squid tenderly cradling a cluster of unusually large eggs.

This observation, seemingly mundane at first, sparked a wave of excitement among the research team.

“The deep sea is the largest living space on Earth and there is a lot left to be discovered. Our unexpected encounter with a squid brooding giant eggs caught the attention of everyone in the ship’s control room,” recalls MBARI Senior Scientist Steven Haddock, who was leading the expedition.

Unraveling the Mystery: A New Species?

Intrigued by the sighting, a team of researchers from MBARI, GEOMAR’s Helmholtz Center for Ocean Research Kiel, and the University of South Florida embarked on a meticulous investigation.

Their analysis suggests that this squid may represent a previously unknown species in the family Gonatidae, a group known as armhook squids.

Closeup view of giant eggs from new species of deep-sea squid. Credit: MBARI
Closeup view of giant eggs from new species of deep-sea squid. Credit: MBARI

What makes this discovery particularly fascinating is the sheer size of the squid’s eggs – approximately 11.6 millimeters (about half an inch) in diameter.

This is twice the size of eggs observed in other brooding deep-sea squids. The squid was also carrying far fewer eggs, around 30 to 40, compared to thousands carried by other species.

Squids and brooding eggs

While maternal care is common among octopuses, it is a rare phenomenon in squids. Most squid species either attach their eggs to the seafloor or release them in buoyant masses that drift with the currents.

These strategies require minimal effort from the mother, but they also leave the eggs vulnerable to predation.

Brooding, on the other hand, is a high-risk, high-reward strategy. It involves the mother carrying and protecting her eggs until they hatch, sacrificing her own nourishment and ultimately her life.

“Brooding takes a lot out of a mother squid,” explains Henk-Jan Hoving, lead author of the study. “She won’t eat while carrying her eggs and ultimately dies after her eggs hatch. But her sacrifice improves the chances that her offspring will survive.”

Why do the squids lay giant eggs?

The researchers speculate that the giant eggs are an adaptation to the stable and predictable environment of the deep sea.

Unlike shallower waters, where food is scarce and predation is high, the deep sea offers a more secure environment for offspring to develop.

By investing in fewer, larger eggs, the mother increases the chances of her offspring surviving to adulthood.

The team estimates that the eggs of this new squid species may take one to four years to develop, significantly longer than the entire life cycle of most shallow-water squids.

This extended development time, they believe, is another adaptation to the slow pace of life in the deep sea.

Deep-sea squids are not just fascinating creatures; they play a crucial role in the ocean’s ecosystem. They are voracious predators of fish and invertebrates, and in turn, they are preyed upon by larger fish, sharks, whales, and seabirds.

They are also a significant food source for commercially important fish species such as tuna and swordfish.

Unraveling the mysteries of the deep

Despite their ecological and economic importance, much about the lives of deep-sea squids remains unknown.

MBARI’s ongoing research is gradually lifting the veil on these enigmatic creatures, revealing their unique adaptations and behaviors.

“Squid play an important role in the ocean — they’re fierce predators and a vital food source for lots of animals, even humans — but we still have a lot to learn about the squid that live in the deep sea,” says Hoving.

With each new discovery, we gain a deeper understanding of the complex web of life that exists in the ocean’s depths.

The giant-egg brooding squid, with its unusual reproductive strategy, is a testament to the resilience and adaptability of life in one of the most challenging environments on Earth.

As technology advances and our ability to explore the deep sea improves, we can look forward to even more exciting discoveries that will reshape our understanding of this vast and mysterious realm.

The study is published in the journal Ecology.

The video of the encounter can be seen here…


Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and


News coming your way
The biggest news about our planet delivered to you each day