Plattform Platform	Reise-Nr. Cruise-No.	Zeitraum Period	Projekt Project	Arbeitsgebiet Working area
Solea	646	04.10.2011 - 24.10.2011	BIAS	Baltic Sea

Fahrtleiter Chief Scientist	Institut Institute	Auslaufhafen Port of departure	Einlaufhafen Port of return	Stationskarte Station map	Schiffsroute Trackchart
Schaber Matthias	Institut fur Seefischerei der VTIG Hamburg	Rostock	Rostock	Karte Map

Ziel der Reise / Objectives of Cruise:

Objective: International acoustic survey for pelagic fish stocks in the Baltic Sea The cruise was part of an international hydroacoustic survey providing information on stock parameters of small pelagics in the Baltic Sea, coordinated by the ICES Planning Group for Herring Surveys with FRV "Solea" participating for the 24th time. The survey area covered the western Baltic Sea including Kattegat, Belt Sea, Ore Sound and Arkona Sea (ICES Subdivisions 21, 22, 23 and 24). Altogether, 1175 nm of hydroacoustic transects were covered. Like in the previous year, the measured NASC-values were below the long time average values in large parts of the survey area with average scattering values often falling below the very low values of 2009 and 2010, with only few exceptions as mentioned below. Contrasting to the previous year, dense aggregations of herring could be recorded in the Ore Sound (SD 23) and distinctively higher scattering values were recorded in the northern part of the Arkona Sea (SD 24), which is in accordance with the record catches yielded in this area (see below). Fish densities in SD 22 were low as in previous years, whereas NASC-values recorded in SD 21 (southern Kattegat) often exceeded long term mean values and values recorded in both 2009 and 2010. For species allocation and identification, altogether 54 fishery hauls were conducted. Unlike in the previous surveys, no "southern species" or exotic species were encountered in 2011.

Messungen / Measurements