The study shows extensive oil contamination of rivers, creeks, and ground waters in Ogoniland, Nigeria. The levels found in the more contaminated sites are high enough to cause severe impacts on the ecosystem and human health: extractable petroleum hydrocarbons (EPHs) ([10-C40) in surface waters up to 7420 lg L -1 , drinking water wells show up to 42 200 lg L -1 , and benzene up to 9000 lg L -1 , more than 900 times the WHO guidelines. EPH concentrations in sediments were up to 17 900 mg kg -1 . Polycyclic aromatic hydrocarbons concentrations reached 8.0 mg kg -1 , in the most contaminated sites. The contamination has killed large areas of mangroves. Although the natural conditions for degradation of petroleum hydrocarbons are favorable with high temperatures and relatively high rainfall, the recovery of contaminated areas is prevented due to the chronic character of the contamination. Oil spills of varying magnitude originates from facilities and pipelines; leaks from aging, dilapidated, and abandoned infrastructure; and from spills during transport and artisanal refining of stolen oil under very primitive conditions.

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Cubomedusae (box jellyfish) possess a remarkable visual system with 24 eyes distributed in four sensory structures termed rhopalia. Each rhopalium is equipped with six eyes: two pairs of pigment cup eyes and two unpaired lens eyes. Each eye type probably captures specific features of the visual environment. To investigate whether multiple types of photoreceptor cells are present in the rhopalium, and whether the different eye types possess different types of photoreceptors, we have used immunohistochemistry with a range of vertebrate opsin antibodies to label the photoreceptors, and electroretinograms (ERG) to determine their spectral sensitivity. All photoreceptor cells of the two lens eyes of the box jellyfish Tripedalia cystophora and Carybdea marsupialis displayed immunoreactivity for an antibody directed against the zebrafish ultraviolet (UV) opsin, but not against any of eight other rhodopsin or cone opsin antibodies tested. In neither of the two species were the pigment cup eyes immunoreactive for any of the opsin antibodies. ERG analysis of the Carybdea lower lens eyes demonstrated a single spectral sensitivity maximum at 485 nm suggesting the presence of a single opsin type. Our data demonstrate that the lens eyes of box jellyfish utilize a single opsin and are thus color-blind, and that there is probably a different photopigment in the pigment cup eyes. The results support our hypothesis that the lens eyes and the pigment cup eyes of box jellyfish are involved in different and specific visual tasks.

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The continued growth and evolution of the offshore wind industry, and the emergence of other novel marine uses such as wave and tidal generators, have upped the ante for spatial planners, as well as consenting and approval authorities in various coastal states. These stakeholders rely on processes such as navigational risk assessments (NRAs) to balance safety and efficiency requirements and to make optimal decisions over use of space. Given the increasingly complex and crowded seascape, however, there are some apprehensions about potential shortcomings in these NRA processes. There is also some concern that these inadequacies may lead to unsafe or

Cumulative impact assessment (CIA) is a promising approach to guide marine spatial planning (MSP) and management. One limitation of CIA is the neglect of seascape connectivity, which may spread the impact of localized pressures to ambient areas, e.g. through lost dispersal and recruitment of organisms. We here, for the first time, incorporate seascape connectivity into a traditional CIA model using a connectivity matrix, exemplified by dispersal of propagules estimated through biophysical modelling. Two connectivity impacts are identified: the source impact represents downstream areas losing recruits because of reduced larval dispersal from sites affected by the pressure, and the sink impact represents loss of recruits originating from upstream areas prevented from settlement in the site affected by the local pressure. By including seascape connectivity in the Swedish MSP‐guiding CIA tool Symphony we demonstrate how to practically account for remote effects of local environmental impact. Our example on blue mussel shows how reducing mussel fitness in a given area may have impacts on mussels far from the acting pressures. Overall, results indicate that connectivity impact for blue mussels plays a minor role in most areas, <10% of the ordinary cumulative impact. However, in some smaller areas, e.g. on offshore banks and the Danish Straits, seascape connectivity may increase ordinary cumulative impact with 20%–30%. In an example of scenario‐based CIA analyses of MSP projections, we demonstrate how impacts of particular management actions, e.g. shipping rerouting and wind power developments, can be tracked far from the original area of influence. Depending on the dispersal ability of ecosystem components, a local pressure may impact a considerable area through seascape connectivity, transgressing management units and national borders. Although the mean connectivity impact may be modest for a single ecosystem component, the consideration of seascape connectivity across multiple ecosystem components may significantly alter the mapping of cumulative impact and the assessment of different MSP scenarios. Synthesis and applications. Our extension of Cumulative Impact Assessment offers a new method for mapping and practically integrating seascape connectivity with ecosystem‐based MSP and other spatial instruments for policy making, such as marine protected areas.

The management of extreme crisis situations in Sweden has shown delays in decisive actions at higher levels during emergencies, such as oil spills. This has been blamed on unclear responsibilities that undermine the decision‐making process. Confusing, conflicting, or delayed orders impede response effectiveness. This article uses network analysis and survey responses to examine the Swedish oil spill crisis management network and show the Swedish Coast Guard, Swedish Agency for Marine and Water Management, Swedish Civil Contingencies Agency and Oil Spill Advisory Service as central organizations. However, the roles of these organizations need to be clarified and communicated better to other organizations. In order to improve coordination of Swedish oil spill preparedness, it is suggested to formalize and strengthen the roles of these central organizations. Weak connections between municipalities in different counties were also observed. This weakness could be overcome by more frequent exercises across counties to improve familiarity.

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