The Chinese mitten crab (Eriocheir sinensis) has lately been found in the White Sea, near the city of Arkhangelsk and in the outlet of the river Severnaya Dvina, web site Utronews.ru reports.
How the crab came to the area is not known, but probably it has walked in the rivers from the Baltic Sea through the lakes of Ladoga and Onega. The Chinese mitten crab lives in both fresh and sea water and can also make significant inland migrations.
This species is very invasive and has been spread to North America and Europe, raising concerns that it competes with local species. The crab is known to have a negative impact on the fishery industry by getting stuck to fishing nets and eating fish and bait. Mitten crabs, where present in large numbers, can block the cooling systems of power stations. They also burrow into river banks, causing them to become unstable and collapse.
Another serious concern is that they have the potential for bioaccumulation of toxins, which makes it a potentially toxic food source for aquatic predators and humans. The mitten crab is also be the secondary host for the Asian lung fluke (Paragonimus westermani), which causes disease in humans and animals. In Asia, where mitten crabs are a delicacy, people regularly suffer lung damage from eating infected mitten crabs, according to Wikipedia.
In the 1960s another invasive crab type was introduced in the Arctic – the king crab. Since then, the population has grown immensely. Some estimates say there are more than 20 million in the Barents Sea. Many environmentalists and scientists say the species negatively alters the sea’s natural biodiversity.
Read also: The environmental danger of king crab
