Horsehair crab

This crab has a hairy shell. It lives in the cold sea. It can be very heavy. People like to eat it for food. It is a special crab. Do you like crabs?

This crab has a hairy shell. Soft spines cover its body. It can weigh over one kg. It lives on the sandy sea floor. It lives in very deep water.

The crab eats many times each day. In the spring, they may eat each other. Mothers carry eggs on their legs. The eggs stay there for a year. Warm water helps the eggs grow. Small crabs hatch in the spring. They float in the sea first. Then they sink to the bottom. It is a busy life for this crab.

The horsehair crab lives in the Northwest Pacific. It lives near the Hokkaido coast. You might know it by its Japanese name, kegani. This name means hairy crab. This is because soft spines cover its shell. These crabs live on sandy sea floors. They can live in shallow water. They can also live 350 meters deep.

These crabs can grow quite big. An adult shell can be 120 mm long. They can weigh more than one kg. They eat three or four times a day. In the spring, they may eat each other. This is called cannibalism.

Female crabs help their babies grow. They attach eggs to their pleopods. These are special parts on their legs. The eggs stay there for over a year. The water temperature helps the eggs grow. Young crabs hatch in the spring. They start as zooplankton. This means they float in the water. By July, they reach the sea bottom. In the Bering Sea, males like warmer water. Females like water that is 2.4 °C. This crab is very important for food in Japan.

The horsehair crab is a special kind of crab. It lives in the Northwest Pacific ocean. You can find it near the Hokkaido coast. It also lives in the Sea of Okhotsk. It lives in the Western Bering Sea too. People call it kegani in Japan. This name means hairy crab. This is because soft spines cover its shell.

This crab has a very interesting life cycle. First, a female crab attaches her eggs to her pleopods. These are special parts on her legs. The eggs stay there for over a year. The temperature of the water controls how fast they grow. Young crabs hatch between March and May. They start as zooplankton that float in the water. By July, they reach the bottom of the sea.

Scientists have studied this species for a long time. Johann Friedrich von Brandt described it in 1848. This crab is very important for food in Japan. People use it in many tasty meals. Because it is so important, people use stock enhancement programs. These programs help keep the crab population healthy. This helps the fishing industry stay strong.

There are many facts about how these crabs live. An adult shell can be 120 mm long. The crab can weigh more than 1 kg. They eat three or four times every day. In the spring, they may eat each other. This is called cannibalism. In the Bering Sea, males live in 3.4 °C water. Females like water that is 2.4 °C.

These crabs live on sandy floors at the bottom. They can live in shallow water. They can also live 350 meters deep. In the past, many were caught. The catch was 27,000 tons in the 1950s. By 2003, the catch was only 2,000 tons. This shows how much the number of crabs changed.

The horsehair crab, known scientifically as Erimacrus isenbeckii, is a unique crustacean. It lives mainly in the Northwest Pacific ocean waters. You can find it near the Hokkaido coast in Japan. It also inhabits the Sea of Okhotsk and the Western Bering Sea. In Japan, people call this species kegani. This name translates to "hairy crab" in English. The name comes from the soft spines covering its shell and legs. This species is very important for commercial fishing and Japanese cuisine.

This crab has a very specific physical structure. An adult carapace, which is the hard upper shell, can reach 120 mm in length. The animal can also grow to weigh over 1 kg. Its body is covered in soft spines that give it a hairy appearance. Like two other species in its family, the female's gonophores are exposed. These are the organs that produce eggs. The crab lives on sandy benthic environments, which are the floors of the ocean. It can be found in shallow water or at depths of 350 meters.

The life cycle of the horsehair crab is a long and complex process. It begins when a female attaches her eggs to her pleopods. These are specialized appendages used for carrying the eggs. The embryonic development is divided into nine distinct stages. Each stage is defined by cleavage and the formation of new appendages. The incubation period for these eggs is estimated to be over one year. The rate at which the embryos grow depends on the water temperature.

After the long incubation, the young crabs finally hatch. This usually happens between March and May. The hatching occurs during the spring phytoplankton bloom in the Sea of Okhotsk. The young crabs start their lives as zoea, which are tiny planktonic larvae. These zoea float in the water as zooplankton. You can tell them apart from similar species by their physical features. Erimacrus isenbeckii zoea lack carapace spines. They also have shorter lateral spines on the fork of their telson.

By July, the young crabs reach the bottom of the sea. Once they settle, they begin their lives on the ocean floor. In the Western Bering Sea, males and females prefer different environments. Males typically live at depths of about 66 meters. They prefer water temperatures around 3.4 °C. Females are often found at depths of around 64 meters. They tend to live in slightly colder water at 2.4 °C.

Feeding and social behaviors are also very active for this species. The horsehair crab is a frequent eater. It may feed three to four times within a ten to twelve hour period. During the spring season, the crabs sometimes engage in cannibalism. This means they eat members of their own species. These behaviors are part of the natural life of the crab in the wild.

Humans have a significant impact on the horsehair crab population. The species is a major commercial resource. In the 1950s, the catch reached a peak of 27,000 tons. However, the numbers have dropped significantly over time. By 2003, the catch had decreased to only 2,000 tons. Because the crab is so important for food, people use stock enhancement programs. These programs are designed to help maintain a successful fishery.

Understanding this species requires looking at many different scientific fields. Its biology is studied through specialized research. The study of its population helps manage the fishing industry. The way it reacts to temperature connects it to oceanography. The life cycle of the zoea connects it to the study of plankton. All these details help us understand the health of the Northwest Pacific ecosystem.