The troll crab is a fascinating crustacean that inhabits the cold, deep waters of the North Atlantic and North Pacific oceans. With its large size, spiny shell, and powerful claws, the troll crab has a formidable appearance that belies its sweet, delicate meat. But what exactly is a troll crab? Let’s take an in-depth look at everything there is to know about this unique sea creature.
What is a Troll Crab?
A troll crab, also known as a Norway king crab or Norwegian king crab, is a type of cold water crab belonging to the Lithodidae family. Its scientific name is Lithodes maja. Troll crabs are a species of king crab, distinguished by their reddish-brown shells, comma-shaped eyes, and bodies covered in long, sharp spines.
These large crabs can measure up to 16 inches across and weigh up to 7 pounds. Their common name comes from Norwegian folklore, in which trolls were envisioned as large, ugly creatures The troll crab’s spiny, oversized appearance evokes these mythical beasts
Where Do Troll Crabs Live?
Troll crabs are found in the North Atlantic and North Pacific oceans. Their range stretches along the cold water coasts of Norway the Faroe Islands, Iceland, Greenland Russia, Alaska, and Canada.
These crabs thrive in deep offshore waters, inhabiting rocky ocean floors at depths of 650 to 6500 feet. Here the waters are consistently cold, with temperatures hovering around 34-39°F. Troll crabs have adapted to survive in this extreme environment.
What Do Troll Crabs Eat?
Troll crabs are omnivorous scavengers, feeding on whatever food sources they can find. Their diverse diet includes algae, mollusks, echinoderms, crustaceans, and even fish carcasses that settle on the seafloor.
To eat, troll crabs use their strong claws to pick and pry pieces of food from the rocks and sediment. Their crab-like mouthparts then grind the food into bite-sized chunks for swallowing.
Interestingly, troll crabs will also feed opportunistically on bait set out on commercial fishing lines. Their scavenging nature leads them straight to these underwater buffets!
What’s the Life Cycle of the Troll Crab?
Troll crabs mate between July and October. Soon after, the female carries the fertilized eggs externally under her abdomen until they hatch. This gestation period lasts about a year.
The larvae that emerge are tiny planktonic creatures. They drift with the ocean currents for up to 3-5 months, developing through several zoeal stages. After their final molt, the larvae settle to the seafloor as juvenile crabs.
At 2 to 4 years old, troll crabs reach sexual maturity. Their lifespan is estimated at up to 15 years in the wild. Throughout their life, troll crabs must periodically shed their exoskeleton in order to grow larger – a process known as molting. To do this, they actually back out of their old shell through a split near the rear!
What Makes the Troll Crab Unique?
Troll crabs exhibit several distinctive traits that set them apart from other king crab species:
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Color – Their rusty reddish-brown shells are deeper and brighter than other king crabs. The color comes from pigments acquired through their diet.
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Spines – Long, sharp spines completely cover their bodies and claws. These act as armor against predators.
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Eyes – Their eyes are comma-shaped, with a deep cleft along the bottom edge. This gives them a wider range of peripheral vision.
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Rostrum – A Y-shaped projection sits between the eyes, unlike the single spike of other king crabs.
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Meat – The meat has a slightly tangy, lobster-like flavor. It’s leaner in texture than other buttery king crab meats.
Is Troll Crab Good to Eat?
Troll crab is indeed edible, though it was not commercially fished until the late 20th century. Its sweet, briny flavor and firm texture make it a seafood delicacy. The meat is extracted from the legs, claws, and body cavity.
Connoisseurs describe the taste as mildly sweet with notes of lobster or crab sticks. While not as rich-flavored as king crab, troll crab has a pleasantly earthy tang. Its lean composition gives it a pleasantly firm, flaky texture.
When preparing troll crab at home, take care to cook it thoroughly to kill any bacteria. And as with any shellfish, exercise caution if you have food allergies or dietary restrictions.
How Did Troll Crabs Get to Norway?
Troll crabs are native to the northern Pacific. So how did they end up inhabiting the waters off Norway’s coast? The history here involves some international relations between Russia and Norway.
In the 1960s, Russian scientists introduced troll crabs to Norway’s Barents Sea. At the height of the Cold War, this move aimed to foster economic ties through joint commercial fishing efforts. The hardy troll crabs flourished in their new Atlantic waters, multiplying rapidly.
By the 1970s, Norwegian fishermen were hauling up troll crabs in abundance. Though not initially welcomed, troll crab fishing has since become an important industry in Norway.
Key Takeaways on the Troll Crab
With its hulking body armor, powerful claws, and sweet meat, the troll crab is truly a unique sea creature. Here are some key facts to remember:
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Troll crabs inhabit deep, cold northern waters of the Pacific and Atlantic.
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They have a spiny reddish-brown shell and comma-shaped eyes.
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Troll crabs are omnivorous scavengers that eat anything they can find.
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They take 1 year to incubate eggs and can live up to 15 years.
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Troll crab meat has a tangy, lobster-like flavor and firm texture.
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This species was introduced to Norway waters in the 1960s.
So now you know all about the curious troll crab and its fascinating natural history. With this complete guide, you can impress your friends with your knowledge at your next seafood dinner!
Troll crab vs King crab
The main difference between the Troll crab vs King crab is that the king crab is significantly larger. The king crab can grow to be up to 10 feet long, while the troll crab only grows to be about 2 feet long. The king crab also has a more robust build, with thick legs and a large body. The troll crab, on the other hand, has thinner legs and a smaller body.
Another difference between these two types of crabs is that the king crab is found in colder waters, while the troll crab is found in warmer waters. The king crab is typically found in the Arctic Ocean, while the troll crab can be found in tropical and subtropical waters.
Finally, the king crab is considered to be a delicacy in many parts of the world, while the troll crab is not as highly valued. This is likely because the king crab is much larger and thus provides more meat.
How to identify a troll crab from a king crab?
King crab and troll crab are both popular types of crab, but they have some key differences that can help you identify them:
- Size: King crabs are generally larger than troll crabs. King crabs can grow up to 6 feet (1.8 meters) from leg to leg, while troll crabs are usually smaller and average around 6-7 inches (15-18 centimeters) across the shell.
- Shape: King crabs have long, spindly legs that are wider at the base and taper towards the end. Troll crabs have shorter legs that are more equal in width throughout.
- Color: King crabs are typically reddish-brown in color, while troll crabs are more of a greenish-brown color.
- Habitat: King crabs are found in colder waters, such as the Bering Sea, while troll crabs are typically found in warmer waters, such as the Pacific Northwest.
- Harvesting method: King crabs are usually caught using large pots that are lowered to the ocean floor and then pulled back up, while troll crabs are caught using smaller traps or lines.
By looking at these differences, you should be able to identify whether you are looking at a king crab or a troll crab.
Discover the Troll Crab: Norway’s Hidden Delicacy
FAQ
Why is a king crab not a crab?
King crabs are not considered “true crabs” because they are more closely related to hermit crabs, despite their crab-like appearance. They belong to the infraorder Anomura, while true crabs are classified under Brachyura.
What kind of crab is on Deadliest Catch?
The show follows crab fishermen aboard fishing vessels in the Bering Sea during the Alaskan king crab and snow crab fishing seasons. The base of operations for the fishing fleet is the Aleutian Islands port of Dutch Harbor, Alaska.
What is the rarest crab?
Blue king crabs are the rarest of all the king crab species in Alaska. Blue king crabs from the Pribilof Islands are the largest of all the king crabs, sometimes exceeding 18 lb (8 kg) in weight.
What is the problem with king crabs in Norway?
An invasive species that became a boon
The problem is that the giant crustacean isn’t an endemic species. Collected in Siberia by Russian scientists, the Kamchatka crab was introduced in the 1960s to the Barents Sea, in the Murmansk region, for economic purposes — an old idea dating back to the Stalin era.