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Paractopus dofleini

Although there are over 100 species of octopuses (Genus Octopus) in the world as well as numerous species of deepwater and pelagic octopuses (Order Octopoda), our knowledge of them comes almost entirely from just a few species. (Octopus vulgaris, Octopus bimaculatus, Enteroctopus dofleini, Eledone cirrhosa).

The Giant Pacific Octopus (Octopus dofleini) is the world’s largest species of octopus, weighing in at 18-25 kg with a 9.5m. arm span.. It has recently been re-classified as Enteroctopus dofleini. The genus Enteroctopus embraces the other giant octopuses of the world, viz. E. dofleini in the north Pacific, E. megalocyathus off S. America and E. magnificus off southern Africa.

Octopuses are cephalopod molluscs characterized by having eight arms, no...

Strongylocentrotus nudus and S. intermedius

Sea urchins are often used as indicator organisms in public aquaria to determine whether the system is functioning properly. These organisms are extremely sensitive to water conditions and are first to show signs of stress, seen when their spines are laid down or are shed.

Warning! Some sea urchins are covered with sharp venom-filled spines that can easily penetrate and break off into the skin – even through a wetsuit. The DAN (Divers Alert Network) website contains useful information on how to handle the unfortunate effects of accidental brushes with these and other poisonous marine organisms. Check out http://www.diversalertnetwork.org/ for any information that you need.

Sea urchins (echinoderms) are a group of marine invertebrates ...

Paralithodes camtschatica

Originating from the Sea of Okhotsk in the Camchatca region of eastern Russia, and also native to the Bering Sea, the red king crab (Paralithodes camtschatica) was introduced to parts of the Russian waters of the Barents Sea in the 1960’s. In the mid 1970’s, individual specimens started to appear as bycatch on both sides of the shared Russian/Norwegian border. Since that time, bycatch numbers have increased significantly in that region.

The king crab is a valuable food source and as the world’s largest edible crab, it is the most commercially important of all crabs...

Haliotis discus hannai

Abalones are highly valued but slow growing, herbivorous marine snails. They belong to a large class of molluscs (Gastropoda) with single-structured shells. There are over 100 species worldwide in the single genus Haliotis, which means ‘sea ear’, a reflection of the flattened shape of the shell. It is no surprise then that it is called ‘Oreille de Mer’ in France. Abalone shells can be oval or rounded, with a row of respiratory pores and large dome towards one end. They are edible molluscs and considered a delicacy). The inner shell of abalone, which has an iridescent green, blue, or pink sheen, is a source of mother-of-pearl

The strong, muscular foot generates enough suction to allow the abalone to fix itself firmly to rocky surfaces, and enables it...

Chionoecetes opilio

The snow crab (Chionoecetes opilio) belongs to class Crustacea, and order Decapoda and is one of the most important commercial species of Decapoda in the

Russian Far Eastern Seas. (It is also the largest crab fishery in Alaska). Snow crabs inhabit the cold waters of the Sea of Japan east of the Korean Peninsula, the Sea of Okhotsk, the Bering Sea, and can be found in the northwest Atlantic, on sandy or muddy bottoms at temperatures ranging from -1 to 5oC and at depths varying between 20 and 420 m.

Because of its wide distribution, the snow crab has a number of other common names, including the spider crab and queen crab in English, crabe des neiges and crabe araignée in French, and zuwai gani in Japanese.

Crabs have broad, flattened, circular bodies that are c...

Oncorhynchus spp. and Salmo salar

The global demand for salmon – that most excellent of table fish – has led to a considerably- sized salmon farming industry in both the northern and southern hemispheres, with large numbers of fish being reared in net-pens. Although the Pacific waters have five endemic salmon species, many salmon farmers prefer the Atlantic salmon, as it is easier to culture.

Inevitably, farmed Atlantic salmon escape from the pens, often in large numbers. This has the effect of having an alien species competing with native species for spawning and rearing habitat...

Mysis littoralis

There are several crustacean forms that are commonly called shrimp although they do not belong to the same order as the true shrimp, order Decapoda, which also includes the lobsters and crabs. Mysid shrimp are not true shrimps, although they look very similar. Mysid shrimp (Mysis littoralis) are members of the order Mysidacea. Often called opossum shrimps because they carry their young in an under-belly pouch, they are smaller in size than the true shrimp.

With their distinct set of antennae, mysids can be easily confused with krill, another shrimp-like creature. Mysids, however, inhabit a different space in the water column. At most times of the year, they are found in shallow, intertidal waters with mud bottoms or granular sediments and seaweeds...

Phoca hispida

The ringed seal is the most common of the Arctic seals. It is not generally found on the open sea, but instead prefer areas where the ice is firm. It is distributed throughout the northern parts of the Baltic Sea, Canada, Alaska, Siberia and along Pacific Japanese coasts.

Adult ringed seals grow to 140-150 cm in length, with females slightly smaller than males. It is similar in shape and color to common seals, although generally darker. The belly is silver gray color and the dorsal side is pale gray with dark spots that are surrounded with pale colored rings.

The ringed seal is an opportunistic feeder, spending most of the time from late summer to early spring on this activity. It feeds mainly on benthic (bottom dwelling), nektonic (swimming) and planktonic organisms...

Boreogadus saida

The Arctic or polar cod (Boreogadus saida) is distributed throughout the ecoregion and occurs in coastal habitats during both summer and winter months. It is able to tolerate a wide range of temperatures, saline levels and turbidities. It is found further north than any other fish species. Arctic cod spawns only once during its life cycle. When newly hatched the larvae feed on copepods larvae (very small crustacea) and eggs. As they grow, they graduate to krill and other crustaceans, then to small fish.

Adult cod feed mainly on fish such as capelin and herring and can grow to 40cm in length, though will typically be around 25cm...

Paralithodes camtschatica

Originating from the Sea of Okhotsk in the Camchatca region of eastern Russia, and also native to the Bering Sea, the red king crab (Paralithodes camtschatica) was introduced to parts of the Russian waters of the Barents Sea in the 1960’s. In the mid 1970’s, individual specimens started to appear as bycatch on both sides of the shared Russian/Norwegian border. Since that time, bycatch numbers have increased significantly in that region.

The king crab is a valuable food source and as the world’s largest edible crab, it is the most commercially important of all crabs...