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Explore the Okhotsk Sea with Heritage Expeditions

The Sea of Okhotsk is a marginal sea of the western Pacific Ocean, lying between the Kamchatka Peninsula on the east, the Kuril Islands on the southeast, the Japanese island of Hokkaidō to the south, the island of Sakhalin along the west, and a long stretch of eastern Siberian coast (including the Shantar Islands) along the west and north. The northeast corner is the Shelikhov Gulf. The sea is named after Okhotsk, the first Russian settlement in the Far East.

Except for the small area touching Hokkaido, the sea is almost completely enclosed by Russian territory. It covers an area of 1,583,000 square kms (611,000 square miles) and it has a mean depth of about 859 metres (2,818 feet). The sea’s maximum depth is 3,372 metres or 11,063 feet. Almost the entire sea came under the supervision of the Soviet Union in 1977 when a 200-mile exclusive economic zone was established. This provided the Soviets favourable conditions to develop fisheries and embark on mineral exploitation. The sea now supplies a large portion of the catches in eastern Russia and valuable deposits of oil and natural gas have been discovered on the sea’s northern shelf.

Early in 2014 a United Nations commission officially recognized the Sea of Okhotsk enclave as part of Russia’s continental shelf. This decision means that Russia has exclusive rights to the 52,000 sq km area described as a "real Ali Baba's cave" that contains reserves of valuable minerals and other natural resources. The recession of Arctic sea ice in recent years due to global climate change had led to increased international legal manoeuvring over the rights to exploit the region's vast untapped hydrocarbon reserves.

The main population centre of the region is Magadan with approximately 100,000 people. It is probably best known as the centre of the notorious Gulags from the Stalin era, where tens of thousands of political prisoners were sent to forced labour camps in the 1930’s to 1950’s.

Mask of Sorrows

Mask of Sorrows, Magadan

Experience this destination by expedition cruising with Heritage Expeditions on the following departures:


With the exception of Japan’s Hokkaidō, the Sea of Okhotsk is surrounded on all sides by territory administered by the Russian Federation. The sea was formed within the past two million years through the combined action of repeated glaciation. The seabed generally slopes from north to south, with a continental shelf along the northern and western margins to a depth of 200m (650 feet). The deepest part is the Kuril Basin (west of the Kuril Islands) at about 2,500m (8,200 feet). Large quantities of continental sediment flow into the sea, primarily from the Amur River. Other sources of sediment include coastal abrasion and volcanic activity. The bottom of the Kuril Basin is predominantly covered with a clay-diatom silt, but closer to the shore are fine, silt-covered sands, coarse sands and pebbles mixed with mussel shells.

The Sea of Okhotsk is the coldest sea in East Asia and in winter the climate over much of the region differs only slightly from that found in the Arctic. The northern and western regions of the sea experience severe weather during the winter because of the influence of the Asian continent. From October until April these areas experience very cold air temperatures, are constantly covered with ice and have very little precipitation – a classic continental climate. To the south and south-east the proximity of the Pacific results in a milder marine climate. The coldest months in the sea are January and February and the warmest are July and August. In the north-eastern part the average monthly air temperature during February is −20°C (−4°F), while in August the average is 12°C (54°F).

Sea of Okhotsk

Sea Ice

The water of the Sea of Okhotsk consists of continental drainage, precipitation and waters flowing from the Pacific Ocean through the straits of the Kuril Islands and from the Sea of Japan through the La Perouse Strait. During the summer months the sea is warmed to a depth of 30 to 50 metres (100 to 165 feet). The general movement of water in the sea is counter-clockwise. Water flows from the Sea of Japan into the Sea of Okhotsk, accounting for the comparative warmth of the south-western area. Warm water is also carried into the sea by Pacific currents. Because of the influence of these currents, the waters of the eastern half of the sea are warmer than those of the western part. For the most part, the currents flow clockwise around the Kuril Islands. In the northern half of the straits they flow into the sea, but in the southern half they return into the Pacific. Ice cover makes an appearance at the end of October and reaches its greatest extent in March. In the coastal areas it extends to the shore and floating ice appears in the open sea. The ice retreats in June, except in the Sakhalin gulfs and the region around Shantar Island, where ice floes are not uncommon in July and sometimes even until August.

In winter, navigation on the Sea of Okhotsk becomes difficult and even impossible in some places, due to the formation of large ice floes. These are generated by the large amount of freshwater from the Amur River which lowers the salinity and results in raising the freezing point of the sea. The distribution and thickness of ice floes depends on location, time of year, water currents and sea temperatures.


Russian explorers Ivan Moskvitin and Vassili Poyarkov were the first Europeans to visit the Sea of Okhotsk in the 1640s. Dutch captain Maarten Gerritsz Vries entered the Sea of Okhotsk in his ship the Breskens in 1643 and charted parts of the Sakhalin coast and Kuril Islands, but failed to realize that Sakhalin and Hokkaido were islands. The Second Kamchatka Expedition under Vitus Bering in 1733 systematically mapped the entire coast of the sea. Jean-François de La Pérouse and William Robert Broughton were the first non-Russian European navigators known to have passed through these waters after Maarten Gerritsz Vries. The first detailed summary of the hydrology of the Sea of Okhotsk was prepared and published by Stepan Makarov in 1894.

The Russian pioneers who founded the town of Okhotsk were skilled builders of river boats, but they lacked the knowledge and equipment to build seagoing vessels which meant that Okhotsk remained a coastal settlement and not a port. In 1682 the settlement of Okhotsk had just eight dwellings and five other buildings. In 1714, Peter the Great sent a party of shipbuilders to Okhotsk to allow faster access to the furs of Kamchatka. By 1716 they had built the Vostok which Kozma Sokolov sailed to Kamchatka. For the next 145 years Okhotsk was the main Russian seaport on the Pacific, supplying Kamchatka and other coastal settlements.

In 1736 Okhotsk was moved two miles downstream to a spit of land at the mouth of the Okhota River, converting it to a proper port. Vitus Bering's two Pacific expeditions (1725–1729 and 1733–1742) swelled the population and the first scholars and expert sailors arrived leading to a great deal of building. In 1742 there were 57 dwellings and 45 other buildings in Bering's ‘expedition settlement’ and eight ships in the harbour. Portuguese Jew, Anton de Vieira, was governor of the town at that time. From 1737 to 1837 there was a salt works on the coast which produced up to 36 tons of salt annually. By 1827 150 exiles and around 100 guards and overseers worked there. Bering's men had found valuable Sea Otters east of Kamchatka and fur hunters began island-hopping along the Aleutian Islands. Their furs were brought back to Okhotsk and most were carried inland to be sold to the Chinese at Kyakhta.

Cultural Colour

Colourful Culture

From at early on it had been clear that Okhotsk had been built on poor site. In addition to a difficult track inland, the harbour was poor and the short growing season and lack of arable land meant that food had to be imported. Around 1750 there were only 37 peasant families and a number of Yakut cattlemen. There was so little pasture in the area that pack horses sometimes had to be returned to Yakutsk unloaded. The harbour was ice-free from May to November but the sailing season was only four months between June and September. The town had been built on a low narrow spit blocking the mouths of two rivers. Although the harbour inside the spit was large, three quarters of it was a mud flat during low water. Large ships could only cross the bar on an incoming or outgoing high tide and sailing ships sometimes had to wait for days for the wind to blow in the right direction. Ice-choked water during the spring breakup frequently flooded the town (20 times from 1723 to 1813), as did high surf on a number of occasions. In 1810 the Okhota River, its mouth jammed by ice, cut a new channel through the spit and isolated the town. In 1815 the town was moved a second time to the spit east of the harbour mouth. Goods now had to be unloaded and barged across the shallow harbour where Yakuts would wade with loads from barge to shore. Fresh water was also a challenge, and had to delivered to the settlement from two and a half miles away.

In 1845 the head of the Russian-America Company depot at Okhotsk, Vasily Zavoyko, oversaw the relocation of the company post south to Ayan. Then in 1849 the Siberian governor Nikolay Muravyov-Amursky decided to move the Siberian Flotilla to Petropavlovsk-Kamchatsky and other government facilities to Ayan. Gradually much business activity shifted south which severely diminished the importance of the town of Okhotsk and the population declined from 1,660 in 1839 to just 100 in 1865.

The Sea of Okhotsk was a magnet for whalers in the mid 19th century. American ships began hunting Right Whales in south-eastern Okhotsk near the Kuril Islands in 1845 and the first Bowheads were caught there in 1847, leading to a preference for this species. Between 1850 and 1853 the majority of the fleet focused their efforts on Bowheads in the Bering Strait region and as that resource diminished the whalers began to shift their attention back to the Bowheads in the Sea of Okhotsk. Hunting here peaked in 1854 when some 160 vessels visited the region. By 1858 the catches had declined, sending most of the fleet back to the Bering Strait region, although ships continued to hunt whales in the Sea of Okhotsk until the early 20th century.


Abandoned Equipment

The town of Magadan, founded in 1929 on the site of an earlier settlement, was a major transit centre during the Stalin era for the predominantly political prisoners sent to forced-labour camps. From 1932 to 1953 it was the administrative centre of the Dalstroy organization which coordinated a large scale and brutal forced-labor gold-mining and forced-labour camp operation. The town also provided the port for exporting the gold and other metals mined in the Kolyma region. The population of Magadan grew rapidly as facilities were developed for the expanding mining activities in the area.

During the Cold War, the Sea of Okhotsk was the scene of several successful US Navy operations to tap Soviet Navy undersea communications cables. These operations have been documented in the book ‘Blind Man's Bluff: The Untold Story of American Submarine Espionage’. The Sea of Okhotsk was the site of the attack on Korean Air Flight 007 which the Soviets accused of spying in 1983 and was also used by the Soviet Pacific Fleet as a ballistic missile submarine bastion, a strategy that Russia continues to this day. Okhotsk was also a launch site of sounding rockets which reached altitudes of up to 1,000km between 1981 and 2005.


The Sea of Okhotsk is one of the world’s most biologically productive seas. River drainage combined with intense intermingling of waters by straits and wind and the upwelling of deep, nutrient-laden ocean waters are all favourable to marine life. In the short summer months when temperatures warm the sea, there is a marked increase in activity. At this time the algae and seaweed flourish, resulting in a population explosion for crayfish, sea mussels, crabs, sea urchins, polyps and various types of fish. Salmon, Herring, Pollack, Flounder, Cod, Crab and Shrimp are all commercially harvested. The Sea of Okhotsk is home to the majestic Steller’s Sea Eagle and numerous seabirds such as guillemots, puffins, auklets and fulmars. Waterfowl and many migratory species are also well represented. Marine mammals include four species of ‘Ice Seal’ – Bearded, Ringed, Largha and the beautifully marked Ribbon Seal – Steller Sea Lions, Northern Fur Seals, Sea Otters, Bowhead, Gray and other whale species. Land mammals such as the Kamchatka Brown Bear, Snow Sheep and the Marmot can also be found in this region.

Ribbon Seal

Ribbon Seal on Sea of Okhotsk Iceflow


Steller's Sea Eagle

Steller's Sea Eagle


‘Feeding the Russian Fur Trade: Provisionment of the Okhotsk Seaboard and the Kamchatka Peninsula 1639–1856’, James R Gibson, 1969

‘Blind Man's Bluff: The Untold Story of American Submarine Espionage’ by Sherry Sontag, Christopher Drew and Annette Lawrence Drew, 1998

‘Magadan’, Michael Solomon, 1971, Auerbach Publishers

‘May Day in Magadan’, Anthony Olcott, 1984, Bantam Publishers

‘The Gulag Archipelago’, Aleksandr Solzhenitsyn, three volumes published 1973–78

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