Copepod faecal pellets have often been considered as rapid transporters of material out of the euphotic zone. Laboratory experiments on their degradation and sinking rates support this view, but field data on the distribution and flux of pellets through the water colomn present contradictory evidence. We suggest that due to the exclusion of metazoans from previously published degradation experiments, such studies may have little relevance to the natural environ-

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Experiments involving three species of copepods(Acartia clausi Giesbrecht 1889, Pseudocalanus elongatus Boeck 1872 and Calanusfinmarchicus Gunnerus 1765) incubated with freshly produced copepod faecal material were conducted and analyzed using automatic image analysis. For two species (A. clausi and C. finmarchicus) the bulk of faecal material was not ingested but was fragmented. This process, coprorhexy, was accompanied by a shift toward smaller particles in the particle size-spectrum. Increases in total volume of the faecal particles after incubation with these copepods led us to propose a process which we refer to as 'coprochaly', derived from the Greek xot/Vaoio,(a loosening, as of bandages). Coprochaly was promoted by manipulation of the faecal material by the copepods. For the third species (P.elongatus) coprorhexy and coprochaly were coupled with coprophagy (ingestion of faecal material). Calculations indicated that the combined effect of coprorhexy and coprochaly reduced sinking velocities of the faecal particles by up to 50%. These processes increase pelagic residency time of particles, increase substrate area for aerobic microbes and presumably enhance remineralization of particulate organic matter.

Cogan, C. B., Todd, B. J., Lawton, P., and Noji, T. T. 2009. The role of marine habitat mapping in ecosystem-based management. – ICES Journal of Marine Science, 66: 2033–2042. Ecosystem-based management (EBM) and the related concept of large marine ecosystems (LMEs) are sometimes criticized as being too broad for many management and research applications. At the same time, there is a great need to develop more effectively some substantive scientific methods to empower EBM. Marine habitat mapping (MHM) is an example of an applied set of field methods that support EBM directly and contribute essential elements for conducting integrated ecosystem assessments. This manuscript places MHM practices in context with biodiversity models and EBM. We build the case for MHM being incorporated as an explicit and early process following initial goal-setting within larger EBM programmes. Advances in MHM and EBM are dependent on evolving technological and modelling capabilities, conservation targets, and policy priorities within a spatial planning framework. In both cases, the evolving and adaptive nature of these sciences requires explicit spatial parameters, clear objectives, combinations of social and scientific considerations, and multiple parameters to assess overlapping viewpoints and ecosystem functions. To examine the commonalities between MHM and EBM, we also address issues of implicit and explicit linkages between classification, mapping, and elements of biodiversity with management goals. Policy objectives such as sustainability, ecosystem health, or the design of marine protected areas are also placed in the combined MHM–EBM context.