Duration: 5 to 15 January 2026

Cruise area: North Sea

Purpose: International Herring Larval Survey

The 496th voyage of the Walther Herwig III is part of the International Herring Larval Survey (IHLS). These surveys serve to regularly record the abundance and distribution of herring larvae in the spawning grounds of North Sea herring stocks. They are coordinated by ICES (International Council for the Exploration of the Sea) and have been conducted in this form since 1972. In addition to the Federal Republic of Germany, the Netherlands is also involved in the IHLS, sampling the relevant study area in December. The results form an important basis for stock assessment and are taken into account when setting fishing quotas. This voyage will investigate spawning grounds in the southern North Sea and on the eastern side of the English Channel.

In addition to recording the frequency and distribution of herring larvae, these will also be obtained for analysis of the fine structure of otoliths (ear bones).

This year, the numbers and developmental stages of plaice eggs from the IHLS programme's plankton catches will again be determined and made available for a research programme investigating the stock development of cod and plaice (PLACES).