In this study, the topic of sexual growth dimorphism in whiting Merlangius merlangus is examined. To understand the magnitude and underlying mechanisms, North Sea International Bottom Trawl Survey (IBTS) data and two additional datasets from the third quarter of 2007 and the first quarter of 2012 were analysed. Merlangius merlangus displays distinct differences in growth parameters between males and females, with females reach...

Gastric evacuation of groups of juvenile (mean 63 mm total length, L T , 0·283 g dry mass, M D ) sprat Sprattus sprattus feeding on brine shrimp Artemia sp. nauplii was studied at six temperatures (7·5, 10, 13, 16, 19·5 and 21·5° C) in the laboratory. Gastric evacuation was best described with a general model: , with S t = stomach content at time t , S 0 = stomach content at time 0, t = time , R , B = constants. The shape para...

Growth patterns inferred from otolith microstructure analysis were compared between sprat Sprattus sprattus early juveniles (26–42 mm total length, L T ) collected in August 2003 in shallow coastal waters of the Kiel Fjord, and sprat recruits (60–95 mm L T ) sampled in October during a pelagic trawl survey of the western Baltic Sea. At the end of August, a sudden and very rapid decline in otolith growth was observed in early j...

The predation of haddock Melanogrammus aeglefinus and whiting Merlangius merlangus on sandeel Ammodytes marinus was investigated based on intensive sampling [performed with a bottom trawl (GOV) equipped with a small meshed codend cover; sediment samples were taken with a van Veen grab] in a restricted area of c . 15 × 20 nautical miles in the northern North Sea during a 5 day period in July 1996. The analysis of the spatial di...

Gastric evacuation experiments, performed with groups of Atlantic mackerel Scomber scombrus and three different prey species: sprat Sprattus sprattus , sandeel Ammodytes marinus and krill Meganectyphanes norwegicus , revealed a strong temperature effect on gastric evacuation ( Q 10 =4.l) and a curvilinear evacuation with a shape intermediate between the square root and the exponential model. From the experiments with krill, wh...

Gastric evacuation experiments were performed on horse mackerel Trachurus trachurus. A nearly full matrix experimental design with respect to the variables predator weight ( Osmerus eperlanus as prey. A general evacuation model without meal size as a variable was fitted to the data on wet weights as well as on dry weights by means of non‐linear regression technique. Two methods of data transformation, relative data and square...

Gastric evacuation experiments were performed on horse mackerel Trachurus trachurus. Discrete meals of different sizes of krill Meganyctiphanes norvegicus, mysids Neomysis integer , brown shrimp Crangon crangon , and herring Clupea harengus were fed to test the effect of prey type on the gastric evacuation. A general evacuation model without meal size as a variable was fitted to the data on dry weights by means of non‐linear r...

Settlement, growth and mortality of the brown shrimp, Crangon Crangon L., were studied in the north Frisian Wadden Sea over a period of 19 months to fill existing gaps regarding the species' life cycle, and thereby to clarify points related to the fishery. Settlement of postlarval shrimp in the shallow areas occurred in three batches: in May; during summer; and an overwintering batch. Compared with an earlier model based on la...