The spatial distribution of anchovy and sardine in the northern Aegean Sea in relation to hydrographic regimes

Acoustic survey data were combined with hydrological parameters with the aim of understanding the relationships between the spatial distribution of anchovy and sardine and environmental regimes. Acoustic and concurrent hydrological sampling was carried out in the Northern Aegean Sea (eastern Mediterranean) during June 1995 and June 1996. In order to examine hydrological parameter selection by anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus), cumulative distribution functions were estimated. Both species were significantly associated with areas of deeper surface and upper mixed layers, which implied an association of anchovy and sardine with anticyclones. Within the range of available temperatures and bottom depths, sardine further showed a significant affinity to warm as well as to shallow waters. These results are discussed in relation to species' life histories and existing knowledge of oceanographic features in the surveyed area.