The Humboldt squid, or Dosidicus gigas, often referred to as the jumbo squid, stands as a notable cephalopod and one of the largest predatory squids. Inhabiting the warm waters of the eastern Pacific Ocean, this species has seen a notable increase in population, expanding its range to regions as far north as Alaska.
This significant expansion has led scientists to speculate about potential impacts on the ocean’s ecosystem, particularly regarding the food chain in various areas. However, the story of the Humboldt squid extends beyond its expansive habits, encompassing a range of intriguing biological and ecological aspects.
Characteristics & Appearance
Considered to be the largest of the Ommastrephid squid family, the Humboldt squid can grow up to 8 feet and 2 inches long (2.5 meters) and weigh up to 100 pounds (50 kilograms). Typically, the adults reach a mantle (body) length of 4 feet and 11 inches (1.5 meters).
Physical Characteristics & Color
A Humboldt squid has a mantle, which takes up most of its body mass, two fins (wings), ten arms and tentacles, and a cone-shaped head with two eyes and a beak.
Among its ten tentacles, two arms are longer and for feeding. The Humboldt squid’s tentacles are also tough on the exterior and double-walled. Each arm contains about 100 to over 200 barb-like hooked suckers. These powerful suckers help them to grab, grip, and tear apart their prey.
Moreover, the Humboldt squid can rapidly change color like other cephalopods (i.e., octopuses and other squid relatives). They have a unique pigment cell called chromatophores that help them change their skin color and texture, and the speed of the color transition occurs so quickly that the human eye is unable to see it.
Not to mention, this vastly magnificent sea creature also has bioluminescent organs. This unique characteristic helps them to generate light (photophores). With the Humboldt squid’s ability to color change and produce light, they can easily camouflage and effectively communicate in the dark.
Additionally, researchers have found around 28 colors that the Humboldt squid can change to as part of their communication pattern. Specific skin colors and lights are believed to elicit different meanings and are used in various combinations as if they have their own language. For example, when under attack by fishers and predators, they become aggravated and aggressive and turn into a bright red color.
Lifespan & Reproduction
For a seemingly powerful and intelligent marine invertebrate, the Humboldt squid has a lifespan of only one to two years. They also rapidly grow after they are born, from around one millimeter to possibly more than a meter within a single year. During most of their relatively short life, they can reproduce over a dozen times.
Humboldt squids reproduce through internal fertilization and typically produce at least one million eggs in a single batch. Some female Humboldt squids can lay over 20 million eggs, which is more than any other known squid species. The smaller females lay smaller egg masses (about 1 meter in diameter) than the larger females (3 to 4 meters in diameter).
The Humboldt squid eggs are gelatinous and transparent, and masses of their eggs float freely in the water. So, the human eye is unable to identify these tiny eggs.
The Humboldt squid lives in the ocean’s depth, from 200 to 700 meters deep (660 to 2,300 feet). As a result, few studies exist on these mysterious sea creatures.
They are native to Mexico’s warm waters and South America’s tip (nearer to Peru). However, in recent decades, they have migrated further north to California, British Columbia, along the northwestern coast of the U.S. state Washington, and even farther near Alaska.
Food & Diet
Humboldt squids are carnivores. They hunt and prey on smaller fish species, crustaceans (i.e., crabs, lobsters, prawns, etc.), copepods (i.e., planktons), small sharks, and other squids or cephalopods. They also come very few times to the surface to feed, making them relatively harder to find and study.
Moreover, their powerful barbed tentacle suckers will quickly strike prey and retract faster than the blink of an eye. The arm suckers contain razor-sharp, tiny teeth inside. In combination with its beak, the Humboldt squid can slice and tear easily into their victim’s flesh. Plus, this squid is known to be aggressive.
Humboldt squids can hunt alone or in groups of thousands (around 1,500 other individuals of their kind). When in a group, they spring after larger prey and devour them quicker than the smaller victims. One of the Humboldt squid’s peculiar hunting methods is that they snatch their prey and pull it deep into the ocean until the victim falls unconscious.
Threats & Predators
The Humboldt squid is not classified as an endangered species. However, they still face several threats. The significant threats they face are humans, climate change, and other predatory marine animals.
Like with many ocean wildlife, there is also a large commercial fish-hunting activity for the Humboldt squid. Fisheries of this animal are most popular around South America and the west coast of the United States. They are mainly caught to serve the European, Russian, and Asian markets to eat.
Climate Change & Global Warming
One of the significant environmental threats to the Humboldt squid is ocean acidification, which is mainly caused by the burning of fossil fuels. As a result, research suggests that towards the end of the 21st century, ocean acidification will significantly reduce the Humboldt squid’s metabolism rate, along with other marine wildlife, thus leading them to find shallower waters where they can consume more oxygen.
However, in recent years, the Humboldt squid has increasingly scattered more towards the north and grown in numbers. Among the theories explaining the change in their migration pattern, one primary reason is the rise in the ocean’s temperature due to global warming.
In particular, studies have concluded that the 1997-1998 El Nino event had a powerfully negative effect on most of the world’s tropics and subtropics. Simultaneously, overfishing of the Humboldt squid’s predators has helped increase the squid’s population.
As a more extended result, the Humboldt squid is believed to become more adaptable to climate change. In turn, researchers predict that they may potentially shift the ecosystem food chain because the Humbodlt squids are notoriously efficient predators.
Additionally, with their increasing migration change and growing population, several concerns have been raised about their potential impact on other major commercial fisheries, such as the salmon industry.
The Humboldt squid has relatively few predators, most of which are larger than the animal itself. Its main predators are sperm whales, swordfishes, billfishes, and large shark species.
The Humboldt squid identifies other unfamiliar objects as potential threats, such as deep-sea cameras and submarines.
The Humboldt squid’s conservation status is unknown, mainly because very little is still known about them to date.
Frequently Asked Questions
1. How big can Humboldt squids grow?
The Humboldt squid can grow up to 8 feet and 2 inches long and weigh up to 100 pounds.
2. How long do Humboldt squids live?
Humboldt squids have a lifespan of only one to two years.
3. How do Humboldt squids reproduce?
Humboldt squids reproduce through internal fertilization and typically produce at least one million eggs in a single batch.
4. Where do Humboldt squids live?
Humboldt squids live in the ocean’s depth, from 200 to 700 meters deep.
5. What do Humboldt squids eat?
Humboldt squids are carnivores and prey on smaller fish species, crustaceans, copepods, small sharks, and other squids or cephalopods.
6. What are the threats to Humboldt squids?
Humboldt squids face threats from humans (commercial fishing), climate change, and other predatory marine animals.
7. How do Humboldt squids defend themselves?
Humboldt squids have powerful suckers on their tentacles, which they use to grab, grip, and tear apart their prey. They are also known to be aggressive.
8. What are the predators of Humboldt squids?
The main predators of Humboldt squids are sperm whales, swordfishes, billfishes, and large shark species.
9. Are Humboldt squids endangered?
The Humboldt squid is not classified as an endangered species, but their conservation status is unknown.
10. How do Humboldt squids communicate?
Humboldt squids communicate through color changing and light production. They have a wide range of colors and lights that are believed to have different meanings and are used in combinations as a form of communication.