Occurrence and Strength of Instantaneous and Intracohort Density-Dependence in Northeast Atlantic Fish Stocks.

Biological reference points (BRPs) used in fisheries management do not include density-dependent (DD) growth, with DD processes only considered in the stock recruitment relationship. Not accounting for DD on somatic growth has led to criticism that such BRPs underestimate the compensatory effects of DD at low stock size, and therefore risk foregone catch opportunities. Here, we analyse 81 stocks from the Northeast Atlantic for evidence of DD growth, defined as the process in which stock size affects somatic weight.

Otolith sectioning reveals higher maximum age in greater weever (Trachinus draco).

Growth and maximum age are two key parameters that inform resilience of fish populations to exploitation. Existing information on those for greater weever inhabiting the eastern North Sea is based on the analysis of whole otoliths. Here, we present a reanalysis using sectioned otoliths.

The effects of Contracaecum osculatum larvae on the growth of Atlantic cod ().

Atlantic cod () from the Eastern Baltic stock have decreased in numbers and condition since the 1990's. Among several causes, an increased prevalence and intensity of the nematode has been discussed. This increase has been attributed to a population increase of the parasites final host, the grey seal ().

Deoxygenation impacts on Baltic Sea cod: Dramatic declines in ecosystem services of an iconic keystone predator.

The intensified expansion of the Baltic Sea's hypoxic zone has been proposed as one reason for the current poor status of cod (Gadus morhua) in the Baltic Sea, with repercussions throughout the food web and on ecosystem services. We examined the links between increased hypoxic areas and the decline in maximum length of Baltic cod, a demographic proxy for services generation. We analysed the effect of different predictors on maximum length of Baltic cod during 1978-2014 using a generalized additive model.