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Since 1928 and over the history of German fishing for brown shrimp ( Crangon crangon L.), several investigations have been made examining the by-catch of this small-meshed fishery. By-catch of commercially valuable fish, particularly flatfish species, has always been a matter of concern. The amount of by-catch comprising fish and invertebrates may actually be high, but figures discussed in public are biased by including discarded undersized shrimp, the target species, and dead material. Many changes in the equipment and practices of the fishery have occurred through the decades. As a result, the overall balance between consumption shrimp, by-catch and undersized shrimp has changed in a positive sense. Those fish still taken as by-catch despite the use of more selective trawls are often discarded and no longer landed for reduction purposes, leaving a chance to survive. Their species spectrum is largely stable over time. In this paper, detailed considerations are made in the particular case of North Sea plaice ( Pleuronectes platessa L.), which are abundant in the by-catch and is a commercially important species. Any large numbers discarded must be regarded in the light of high numbers of offspring, the large discards of the flatfish fishery and the high natural mortality of juvenile plaice. From that the conclusion is drawn, that the German shrimp fishery meets criteria of sustainability in respect to the target species and by-catch situation. [ABSTRACT FROM AUTHOR]

During routine coastal Demersal Young Fish and Brown Shrimp Surveys (DYFS) in 2002, the reticulated dragonet Callionymus reticulatus was found in addition to C. lyra in the Wadden Sea of Schleswig Holstein, Germany, using a 3-m experimental brown shrimp beam trawl. The survey area extended from 7 to 9°E and from 53°30′N to 54°55′N. It is the first proven occurrence of this species east of Helgoland in the Wadden Sea National Park area and adjacent waters. Data from two other beam trawl surveys (in May 2002 on sole and in January 2003 on shrimp) were additionally used to cover a wider area of the German Bight and during different seasons. [ABSTRACT FROM AUTHOR]

This article investigates the presence of cottid fish known as Norwegian bullhead in southeastern North Sea. The sites near Helgoland seem to be the southernmost distributional locations recorded in the North Sea and are a late proof of Fedorov's occurrence statement concerning Germany. Due to the small size of Micrenophrys lilljeborgii, it is unlikely to be caught regularly by normal fishing gear used in the deeper parts of the North Sea. Cottid fish is vulnerable to predation by larger fish.

Abstract: The organotin (OT) compounds tributyltin (TBT) and triphenyltin (TPhT) are potent biocides that have been used ubiquitously in antifouling paints and pesticides since the mid-1970s. These biocides are extremely toxic to marine life, particularly marine gastropod populations. The European Union therefore took measures to reduce the use of TBT-based antifouling paints on ships and ultimately banned these paints in 2003. Despite sufficient data on OT concentrations in marine gastropods, data are scarce for other species such as the North Sea brown shrimp (Crangon crangon), a dominant crustacean species in North Sea inshore benthic communities. The present study provides the first spatial overview of OT concentrations in North Sea brown shrimp. We have compared these data with historical concentrations in shrimp as well as with sediment concentrations. We have also addressed the effect on the shrimp stock and any human health risks associated with the OT concentrations found. TBT and TPhT in shrimp tail muscle ranged from 4 to 124 and from 1 to 24μgkg−1 DW, respectively. High levels are accumulated in estuarine areas and are clearly related with sediment concentrations (biota-sediment accumulation factor ∼10). Levels have decreased approximately 10-fold since the ban took effect, coinciding with a recovery of the shrimp stock after 30years of gradual regression. Furthermore, the OT levels found in brown shrimp no longer present a human health risk. [Copyright &y& Elsevier]

Time series on Crangon crangondensities in the German Wadden Sea show a considerable degree of interannual variability, for the entire region in spring and in autumn as well as for three subareas, North Frisia, East Frisia and Elbe estuary. Across the entire survey area C. crangondensity was inversely related to water depth. In autumn after the recruitment, settlement shrimp densities are correlated across a larger spatial scale (>100 km longshore), whereas in spring the overwintering adult spawning stock is uncorrelated across subareas. Interannually, extreme density variations can develop even over a short time span of 1 yr. On a large spatial scale shrimp abundance in autumn was correlated with year-to-year changes in physical environmental and biological parameters, winter water temperature, autumn river runoff and the winter NAO index. On a regional scale (North Frisia), density of gadoid predators was an additional component affecting shrimp stock abundance. No correlations to such parameters could be detected for the C. crangonstock in spring. Possible causes for the spring situation and additional sources for variability are discussed. [ABSTRACT FROM AUTHOR]