Knowledge of connectivity pathways in the marine environment is crucial for understanding the spatial structure of populations and for developing appropriate monitoring and management strategies. Here, we used the mussel Mytilus galloprovincialis as a model species to investigate connectivity patterns within the Berlengas and Arrábida Marine Protected Areas (MPAs) along the central Portuguese west coast. We generated an atlas of location-specific environmental markers based on the microchemistry of bivalve larval shells (using laser ablation inductively coupled plasma mass spectrometry). This atlas was then employed to trace the natal origins of newly settled mussels and generate connectivity matrices among populations. Our results reflected 3 distinctive chemical signatures in larval shells, corresponding to 3 regions: Estremadura, Cascais and Arrábida. Linear discriminant analyses allowed for a high reclassification success (average of 79.5% of jackknifed cross-validated cases correctly assigned) based on 8 of the 16 trace elements analyzed (B, P, Co, Cu, Zn, Ce, Pb and U). The population connectivity matrix identified different dispersal pathways for mussel larvae, in particular a predominantly northward dispersion pattern in July 2013. This pattern was consistent with simultaneous environmental physical data, which confirmed an extended period of wind reversal and upwelling relaxation. The Arrábida MPA was an important source population for the other 2 regions and showed high rates of self-recruitment but limited connectivity to the Berlengas MPA. These direct measures of demographic connectivity can be a powerful tool to inform policymakers on the conservation and management of ecologically coherent networks of protected areas in coastal marine ecosystems.
Historically, protected areas were often designated using criteria other than biodiversity conservation as the primary objective. With the emergence of the science of systematic conservation planning, the designation of new protected areas is increasingly made with explicit conservation objectives in mind. However, assessments of the performance of protected area systems typically include all protected areas, regardless of when they were designated, potentially obscuring recent improvements in conservation planning decisions. Thus, it is often unclear to what extent systematic conservation planning principles have influenced the placement of new protected areas. Here, we compare recently designated protected areas in Australia with the protected area system that existed prior to the introduction of systematic conservation planning guidelines in 2000. We ask whether there is a difference between past and recent protection in terms of (i) the size and spatial distribution of protected areas, (ii) the characteristics of broad regions in which protection is concentrated, and (iii) the extent to which protected areas represent ecosystems and threatened species in comparison with selecting protected areas at random. We find that the protected area system was historically biased toward areas with steep slopes and low human populations. In contrast, recent protection is more likely to be allocated to regions with high human population and high numbers of threatened species; we show that this effect is not simply a result of biases in the places now available for conservation. Despite this successful realignment of practice, we find that the increase in protected area coverage in poorly protected regions has occurred more slowly than expected if protected area selections were fully guided by systematic conservation planning principles. Our results demonstrate rapid progress in improving Australia's protected area system in the last decade, and highlight the importance of separating recent from historical additions to the protected area system when measuring the performance of conservation decision-making.
Most of the fishers of coastal East Africa particularly among the Bajuni, Kojani, Macua and Vezo ethnic communities have historically practiced migration. This study explores the strategies used by migrant fishers’ of Pemba in the Western Indian Ocean region. By adopting a modified sustainable livelihoods framework (SLF), the study uses in-depth interviews and questionnaires to explore the life histories of the fishers in migrant communities, their motivations to migrate, and their associated socioeconomic and ecological implications. Results point out to a complexity of factors contributing to migration including natural, to economic and social factors. Interaction of such factors is instrumental in shaping fisher migration as an activity into an important livelihood strategy. The study concludes that SLF provides holistic understanding of migration. However the incorporation of the ‘livelihood spaces’ extends this knowledge by integrating the spectrum of spatial aspects. This understanding is critical in the design of policies and interventions necessary to ensure resource sustainability and secure fishers livelihoods. This multi-method approach is critical in empirical study of fisher migration.
Designing a marine monitoring program that detects CO2 leaks from subsea geological storage projects is challenging. The high variability of the environment may camouflage the anticipated anisotropic signal from a leak and there are a number of leak scenarios. Marine operations are also costly constraining the availability of measurements. A method based on heterogeneous leak scenarios and anisotropic predictions of chemical footprint under varying current conditions is presented. Through a cost function optimal placement of sensors can be given both for fixed installations and series of measurements during surveys. Ten fixed installations with an optimal layout is better than twenty placed successively at the locations with highest leakage probability. Hence, optimal localizations of installations offers cost reduction without compromising precision of a monitoring program, e.g. quantifying and reduce probabilities of false alarm under control. An optimal cruise plan for surveys, minimizing transit time and operational costs, can be achieved.
While the development of maritime economic activity is increasingly encouraged, the consideration of its impacts constitutes a real challenge. The limitations of the implementation of the mitigation hierarchy have been widely discussed in scientific literature, yet data on marine biodiversity offset practices remains scarce. In this study, we investigated the use of Environmental Impact Assessments (EIAs) as suitable instruments to achieve the No Net Loss objective. Drawing on a French approach developed for the initial assessment of the European Marine Strategy Framework Directive, we examined the pressures and impacts related to various marine development projects and the effectiveness of the mitigation hierarchy in limiting these. An analysis of 55 recent French environmental impact studies showed that only 7% of the proposed measures had the aim of offsetting predicted degradation of sites of remarkable biodiversity. This can be partly explained by the lack of a clear definition of ‘significant impact’, which varies greatly depending on what is impacted, in turn allowing socio-economic activities to benefit more easily from offset. Furthermore, offsetting does not always constitute the final step of the mitigation hierarchy, highlighting the need to reinforce avoidance and reduction steps. Although we acknowledge the role of EIA in mitigating the negative impacts of development projects, synergies with other European marine environmental policies such as the Marine Strategy Framework Directive (MSFD) and the Maritime Spatial Planning directive (MSP) should be developed in order to improve current practices.
The delimitation of maritime zones and boundaries foreseen by the United Nations Convention on the Law of the Sea is a factor of economic growth, effective management of the coastal and ocean environment and the cornerstone for maritime spatial planning. Maritime boundaries form the outermost limits of coastal states and their accurate computation is a matter of national priority. The final delimitation agreement is ultimately a political decision; however the cartographer/GIS expert should portray the zones’ limits with the best possible accuracy. Existing applications tend to address this issue with their weakness being that the delimitation is a complex and time-consuming process. There, the subject is addressed in a fragmented way with the user composing the outer limits from partial results. This paper presents a cohesive methodology for the automated delimitation of the median lines and maritime zones between all states in a region based on the Voronoi tessellation of maritime space. Furthermore, through a case study, it presents and evaluates the results of this methodology and its implementation and demonstrates its ability to delimit the zones and boundaries, unilaterally and bilaterally, without the user’s intervention.
The New Zealand sea lion (Phocarctos hookeri) is a threatened endemic species, with only three breeding colonies in the sub-Antarctic islands. Since 1993, there has been evidence for recolonisation of mainland New Zealand. Yet the coast that the sea lion has returned to only has fragmented and unevenly distributed potential habitats due to coastal urbanisation and development. Therefore, the need to identify and protect potential breeding habitats for recolonisation is a priority for management.
A GIS-based multi-criteria analysis was used to identify potential suitable habitats for a 1600 km length of the NZ South Island coast based on distance to anthropogenic disturbance (urban areas, roads), distance to desirable environmental features (beaches, estuaries) and presence of suitable habitat/land access. From this model, we identified preliminary suitable habitat for breeding sites on the Otago Peninsula (east coast) and Catlins Coast (south). We independently detected some of the current dominant areas used by recolonising sea lions as well as identifying some promising new sites.
We discuss the limitation of the results of this case study and the need for further data to be added to the model in the face of limited data availability. Overcoming this data limitation will meet an increasing need for a New Zealand-wide study for determining potential habitat for NZ sea lions. The results of such a study would identify areas to allow real-world management (protection or restoration) of the limited potential breeding sites for New Zealand sea lions. This new method could also be used for other recolonising species and encourage management of areas most likely to be recolonized by them.
Coastal areas of developed countries have been altered by human activities, especially since the mid-20th century. This has notably affected the flow of ecosystem services that these environments provide. In this context, this paper’s research has focused on the historical evolution of socio-ecological dynamics and ecosystem services in a Mediterranean coastal landscape, characterized by the intense development of recent decades and the high biodiversity value. Qualitative and quantitative data were gathered and analyzed through different methods (document and spatial analysis, statistical treatment). Results show the long history of many ecosystem services (increase/decrease in food provisioning, stabilization/decline of regulating services and no use/intense use of cultural services) and their decline in recent decades due to industrial and residential development (which expanded from 1.7 to 47.5%). To overcome this situation, this paper discusses the current state of ecosystem services and conservation tasks carried out and how the results of the research can be included in the different elements of the governance of shoreline areas.
A dedicated observer programme was carried out in gillnet and entangling net fisheries off the west and southwest coasts of Ireland to monitor interactions with seals. No seals were observed as bycatch in gillnet fisheries suggesting the risk of bycatch in observed gillnet fisheries is low. Grey seals (Halichoerus grypus) and to a lesser extent harbour seals (Phoca vitulina) were observed as bycatch principally in large mesh tangle nets targeting crawfish (Palinurus elephas). Observed bycatch levels, proximity of grey seal colonies to crawfish fisheries and similar habitat preferences suggest that the risk of seal bycatch in tangle net fisheries for crawfish on the west and southwest coasts of Ireland is high. Factors affecting bycatch in tangle nets were modeled to investigate potential bycatch mitigation measures. Crawfish and monkfish (Lophius spp.) catches, depth of gear deployment and larger mesh size were significantly positively correlated with seal bycatch. Development of mitigation measures such as improved net visibility, use of smaller mesh size and reintroduction of pots has major potential to reduce seal bycatch in the observed tangle net fishery. Growing seal populations in regions where tangle netting for crawfish is most prevalent could be related to factors such as benefits accrued from depredation and possible immigration from adjacent populations in the UK. More explicit conservation objectives will likely be needed to provide an impetus for development of proposed mitigation measures and bycatch reductions in Ireland. Results of this study also have broader ramifications for management of pinniped bycatch in large mesh gillnet and entangling net fisheries, which are widespread but poorly studied in European Community waters.
The Department of the Interior manages offshore oil and gas activities in federal waters. While the agency has proposed and/or enacted important improvements to the rules that govern some of those activities, it has not modernized the regulations that govern offshore oil and gas planning, lease sales, or the review and permitting of exploratory drilling. These phases of the process are overseen by the Bureau of Ocean Energy Management (BOEM), and, as was shown in our earlier publication on this topic, are ineffective and in need of modernization. In this Article, we argue that fundamental reform is necessary and highlight a series of key themes and topics that must be addressed to improve the regulatory process and promote better, more consistent management outcomes. While the Article draws on examples from frontier areas—in particular the U.S. Arctic Ocean—the recommended changes would apply to and benefit all areas of the OCS.