The dynamics of the nematode larvae, Anisakis simplex (Rud.) invasion in the South Western Baltic herring (Clupea harengus L.)

Abstract

The analysis of an infestation level of the Baltic herring (Clupea harengus L.) with Anisakis simplex (Rud.) larvae as well as otoliths and gonad maturity examinations allowed to distinguish, among the Pomeranian Gulf and adjacent area herrings, 4 herring stocks appearing succesively in the region investigated. The seasonal occurrence of Anisakis larvae in herring from the examined fishing regions is related to the sequence of arrival of the different stocks. Suspected sources of invasion are discussed, the Anisakis invasion being related to the North Sea herring migrations.