This study reports on the development and evaluation of a predictive model for the accumulation of polychlorinated biphenyls (PCBs) in phytoplankton which incorporates the kinetics of the process. The model includes a surface sorption term, uptake and loss rate coefficients, and a biomass dilution term. Laboratory data collected from the accumulation of 40 representative PCB congeners in four representative algal species were used to parameterize the model, and the performance of the model was evaluated on a set of independent laboratory data and a set of field data collected from Green Bay, Lake Michigan. Model predictions were compared to predictions from an equilibrium model. Under low growth conditions, the predictions of the kinetics model and the equilibrium model were similar. However, for data collected during periods of intense growth, equilibrium predictions deviated significantly from the observed values and from the kinetics model predictions by as much as 3 orders of magnitude. Concentrations calculated on a lipid basis by both models significantly underestimated the observed accumulation and questioned the hypothesis that PCBs accumulate in the lipid portion of phytoplankton. However, on a relative basis, the kinetics model reproduced the observed accumulation significantly better than the equilibrium approach.

Experiments were conducted to compare the bioaccumulation of hydrophobic compounds among different phytoplankton divisions, and to evaluate the factors that affect species‐specific differences. Unialgal batch cultures of Selenastrum capricornutum, Anabaena sp., and Synedra sp. were exposed to 40 PCB congeners at 11°C for 40 d. PCBs selected for this study represented all 10 homologs, different substitution patterns, and a wide range of physical‐chemical properties representative of compounds known to bioaccumulate in aquatic organisms. Congener‐specific partitioning into the algal phase over time was investigated. Species differences were observed in the rate and magnitude of accumulation. For all species, a rapid association of PCBs with the algal phase was followed by a slower partitioning from the media to the algae, which continued for several days. Bioaccumulation factors (BAFs) could be predicted from Kow for PCB congeners with log Kow values <6.0, whereas no such correlation was found for the more hydrophobic congeners. Normalization of BAFs to total lipid or glycolipid content reduced some of the variability between species for the less hydrophobic congeners, but not for the more hydrophobic congeners. Normalization of BAFs to the phospholipid fraction reduced species variability for the more hydrophobic congeners, supporting the hypothesis that these compounds have restricted membrane permeability.

Trends towards a more participatory agenda in policy-relevant science imply that the roles and work tasks of scientists become more multifaceted. In Europe, the increased use of multiannual plans creates a need for fishery scientists to contribute with their expertise in a wide variety of situations. We identify and characterize four roles for scientists as developers , reviewers , judges , and messengers in arenas where management plans are produced and evaluated. Using examples of producing and evaluating management plans for pelagic fish stocks in Europe, we present different scientific roles and how they may intertwine. The examples illustrate that fishery scientists increasingly interact with advisory councils and industry stakeholders when performing roles as developers and messengers. The roles as reviewers and judges are typically affiliated with evaluation processes carried out under the auspices of the marine science and advisory organization International Council for the Exploration of the Sea (ICES). While it may be difficult to separate the roles in practice, we argue that it must be emphasized to be aware of their different requirements to ensure that scientific credibility is not compromised. By asking the question “What hat are you wearing?”, we encourage individual fishery scientists, their employers, and ICES as a network organization of expertise to reflect on roles, affiliations, mandates, and possible consequences of wearing different “hats”.

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This paper investigates how different kinds of knowledge are mobilised in interactions between the stakeholders, scientists and bureaucrats who are involved in EU fisheries management. It reports on an initiative led by the North Sea Regional Advisory Council aimed at making a long-term management plan for Nephrops fisheries in the North Sea. The sharing of knowledge between the actors is explored using insights from organisation management, focusing on the kinds of resources and efforts that are needed at different boundaries to allow knowledge sharing and knowledge production to occur. The findings point to the challenge of reaching a common understanding between actors when both novelty and high stakes are involved. Experiences gained during this pioneering initiative raise questions about how far it is possible to take a 'bottom up' collaborative process aimed at developing management instruments within a setting where there are conflicts of interests between the stakeholders involved.

This article describes and discusses consortia models in Europe. Emphasis is given to those consortia that support content provision and access to electronic information resources in society. Four country cases are introduced as examples of the heterogeneous solutions chosen by the consortia. The main results and impact of the consortia are discussed. International cooperation has played an important role in the development of consortia in Europe. Regional and global collaboration initiatives are also discussed.

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