Kingdom    Animalia

Phylum      Arthropoda

Class         Malacostraca

Order         Decapoda

Family        Lithodidae

Genus        Paralithodes

Species      P. camtschaticus

Red King Crab Basics

The red king crab, commonly known as the Alaskan king crab or Kamchatka king crab, is the biggest king crab species found in the far northern Pacific. It is noted for the enormous fishery that targets this species in this region.

Red King Crab Description

The red king crab has a carapace that is around 11 inches wide and a leg reach of about 6 feet. The males are larger than females, with the largest weighing around 28 pounds. It has a strong shell or exoskeleton coated with small, rigid spines for further defence.

As with other true crabs, prawns, and lobsters, the king crab resembles a decapod, having ten legs. They seem burgundy or brown in hue, despite their name, which relates to their colour when cooked.

Distribution and Habitat

Red king crabs are found only in the Northern Pacific Ocean. In the 1960s, this species was brought to the Barents Sea, and it may also be found in the Bering Sea. It prefers cold water, with temperatures ranging from 29 to 55 degrees Fahrenheit. When juvenile, the red king crab likes shallow waters, only about 65 feet deep. After the age of two, individuals are often found at depths between 65 and 165 feet.

They often participate in “podding,” in which groups of crabs assemble in huge numbers in highly concentrated groups at night. Because they are still young, this offers them some safety from predators. Adult king crabs ultimately live in 650-foot-deep seas on sandy bottoms. However, they will mate in shallower, rocky areas.

Diet and Predators

The red king crab is an omnivorous creature that eats practically everything. This includes consuming expired and decaying animals and plant debris and also hunting a variety of invertebrate organisms utilising their front limbs, which are used to grip and manipulate prey and food.

The red king crab is preyed upon by an assortment of sharks, fish, cephalopods, and whales in its natural habitat. This is regulated mostly by the crab’s life cycle, with larger, fully grown crabs becoming less susceptible to attack. In the native habitat of the red king crab, the giant pacific octopus is among the most vicious crab killers. On a daily basis, humans consume red king crab, making it one of the world’s major crab fisheries.

Reproduction

Internal fertilisation occurs in red king crabs. Females brood fertilised eggs for up to a year on the bottom of their bellies. Individuals will go to shallower areas to mate throughout the winter when the surface waters are suitably chilly. Pregnant females undergo this migration in order to breed, release the offspring from the water stream, and mate repeatedly before retreating to deeper waters during the summer. Females can discharge from 50,000 to 500,000 larval crabs throughout each annual spawning cycle during the duration of their 20-30 year lifespans.

Fun Facts about the Red King Crab!

If you have ever had “king crab legs,” you are surely acquainted with the red king crab. The species, on the other hand, is intriguing and helps us to learn many important facts and biological ideas in addition to being on our plates as crab legs for supper.

The Red Crab

The Bering Sea and the North Pacific Ocean are home to the red king crab. It did, however, attract the notice of another significant red organisation in the 1960s. The species was introduced to the Murmansk Fjord, a section of the Barents Sea closer to Europe, by the former Soviet Union. Their objective was to establish a new, thriving fishery in this location.

The initial batch of crabs was carried on land, but they did not make it. Some were flown in instead. These individuals survived and formed a colony in the region, where they are now considered a non-indigenous species.

Stalin’s Crabs

At first glance, the transfer of some species to new places may look harmless. There are regularly unanticipated consequences that may be disastrous to the environment. Where it was initially introduced, in the Barents Sea, the red king crab has produced issues.

Because one of its primary natural predators is absent, the colossal Pacific octopus, in the European oceans, this community has grown almost unchecked for many years and is today enormous. The animal will devour nearly everything in its path, since it is an omnivore. Local fishermen and experts claim that this is essentially producing ‘deserts’ where native species and life in general are absent.

The species has also made its way to the Norwegian coast since the 1960s and is moving south at a rate of roughly 30 miles per year. This has sparked suspicions that comparable consequences of those seen in the Barents Sea would occur here as well, with particular worry expressed for the cod spawning grounds around Lofoten. There’s also evidence that the species likes to eat capelin egg masses, a little fish that is an important source of food for cod. Because of these dangers, residents have come to demonise the species, calling them “Stalin’s Crabs.”

Molting and Exoskeletons

The red king crab’s exoskeleton is a skeleton on the outside of its body, similar to that of other decapods. The shell, in contrast to the endoskeletons seen in humans, does not enlarge. To get bigger, individuals need to moult or shed their shells on a constant schedule. Prior to that, someone begins to build a new, larger skeleton within the old one.

As it becomes larger, the old shell will no longer be able to contain it, causing it to break apart. The new exoskeleton hardens even more after removing the previous outer shell. The crab’s new exoskeleton, on the other hand, may remain soft for many days, rendering it more vulnerable to attack than it otherwise would be.

Doesn’t Hold its Breathe

Like fish and sharks, the red king crab possesses gills that allow it to breathe underwater. Two branchial chambers occur inside the carapace, the crab’s main body. The gills are located inside this chamber and are protected by a strong chitinous cuticle covering that is permeable to gases, letting oxygen pass through. A scaphognathite is a unique appendage used by crabs to guarantee water circulation inside the branchial chamber. Water is drawn in from beneath the crab’s walking legs and ejected via prebronchial apertures, which are placed beside its mouth.