WWF in the Arctic: Barents Sea

The Barents Sea Ecoregion is one of the most productive oceans of the world. The ice edge is particularly productive.

In autumn and winter, a vertical mixing of water masses occurs throughout the sea, bringing deep sea nutrients to the surface layers.

In spring and summer, melting ice stabilises the upper 20-30 metres of the nutrient-enriched water column (water of lower salinity remains on top), creating a layer where phytoplankton production is not restrained by vertical mixing of water-masses.

As the melting ice edge retreats north, bodies of water with high winter concentrations of nutrients are exposed, creating an environment with stable water and plenty of light and nutrients.

This causes an algal bloom to occur in the spring. Following the algal bloom is a substantial growth in zooplankton, followed by feeding migrations of plankton-eating fish such as capelin, which links most of the primary production to the other trophic levels of the ecosystem.