The main aim of the ecosystem survey was to map the distribution and abundance of the young and adult stages of several demersal and pelagic fish species, and in addition to this gather information about hydrographical features, zooplankton, benthos, seabirds and sea mammals. Depleted content of oxygen in the bottom layer of the southern Barents Sea that started in 1998 has continued in summer and autumn 2004. Phosphate content in the Barents Sea in summer was close to the long-term mean and reduced in autumn because of late termination of water blooming. Total abundance indices of 0-group fish were estimated by new Norwegian-Russian method used two ways. The new indices show the same richness of year classes as was found by traditional ind...