The Gulf of Gabes is considered as one of the most productive areas of the southern Mediterranean Sea and it plays an important role in Tunisian economy. It is known to be an archetypal ecosystem in which the effects of fisheries are the most pronounced. Based on the stock assessment outcomes, it is as a highly exploited ecosystem. Thereupon, it becomes necessary to establish adequate measures to facilitate the recovery of the marine resources. The most important sets of management measures regard the establishment of Marine Protected Areas (MPAs). However, these management plans should be assessed beforehand to make sure of the relevance of the measure and its impact on marine resources. Modeling may significantly enhance our understanding of the likely impacts of fisheries management plans on groups that are very difficult to study and this approach gives insights at larger spatial scales. We used Ecospace to investigate the potential impacts of several spatial management plans on the ecosystem structure of the Gulf of Gabes. The Ecospace model is based on the existing Ecopath model elaborated by Hattab (2013). The simulation were carried over a 15-year period. The outcomes of the simulations, suggest that the implementation of MPAs in the Gulf of Gabes could be simultaneously beneficial for the ecosystem and fishing activities. However, the benefits are related to the characteristics of the MPA. The spatial simulations highlight that the location is crucial to the success of the MPA. Additionally, an increase in the size of a MPA can result in an increase in the spillover effect and, consequently, in catches in the neighborhood without harming ecosystem integrity. The configuration of the implemented MPA is of capital importance, a set of many small MPAs is more beneficial than fewer and larger MPAs, especially in terms of catches.
The Kenai River Fishery is a unique social–ecological system (SES) with nearly 50 federal, state, local, and nonprofit groups influencing its political, ecological, and social structure. While ecological data exists for this fishery, the complexity of its stakeholder relationships has not been investigated. Stakeholder interactions can directly influence how science is integrated into management decisions and therefore affect the adaptive capacity of SES, such as the Kenai River Fishery. Drawing from the existing stakeholder literature, this methods identifies and ranks the key SES stakeholders and describes their roles. This study approached the question of which stakeholders should be included in a future SES adaptive capacity study by (1) identifying the key stakeholders within the Kenai River Fishery, (2) ranking each stakeholder’s investment within the fishery using eleven categories of interaction, and (3) using these eleven categories to characterize each stakeholder's role within the SES. The largest number of stakeholders fall into the secondary investment category, showing that a relatively small number of resource managers are interacting with a large number of diverse nonprofit organizations. The top ranking stakeholders in this study will be invited to attend participatory scenarios workshops that will build the foundation for a deeper scenarios-based analysis of SES adaptive capacity.
The notion of clusters has increasingly been integrated into regional economic development policies. This paper examines the extent to which maritime cluster policy strategies in Québec's coastal region are associated with employment growth in the region, and more specifically, science-based, skill-intensive employment. Whilst early evaluations conducted about a decade ago suggested that cluster policies implemented from the mid-1990s onwards had little effect, the question addressed in this paper concerns their effect over the long term. Based on descriptive statistics and trend analysis, the results reveal that the sectors targeted by the cluster policies have tended to grow more slowly within the cluster, and that jobs in the cluster are decreasingly science-intensive. At best, cluster policies have had a weak and diffused effect. This is in keeping with other recent work on clusters, and calls into question policy attempts to generate cluster dynamics in regions where these do not emerge spontaneously.
The purpose of this paper is to analyse problems with the legislative framework and institutional arrangements underpinning marine protected area and marine resource management in Indonesia. The paper identifies current difficulties with coordination, functional overlap, and unclear mandates of government agencies for dealing with marine protected areas and marine resources management. Analysis of the legal framework and institutional arrangements is not intended to solve the problem as a whole, but to assist in explaining the broad and complex issues arising from the enactment of the new Regional Government Act. This paper suggests improvements to marine protected area and marine resource management in Indonesia through enhanced coordinating mechanisms and amendments to the new Regional Government Act. The paper argues that an adequate and appropriate legal framework and institutional arrangement will promote sustainable development and management of Indonesia marine areas.
In coastal areas, demographic increase is likely to result in greater numbers of recreational users, with potential consequences on marine biodiversity. These effects may also occur within Marine Protected Areas (MPAs), which are popular with recreational users. Our analysis builds on data collected over a ten-year period during three year-round surveys to appraise changes in recreational boating activities in coral ecosystems. Results show that the number of boaters has greatly increased, particularly so within MPAs during weekends and the warm season, when peaks in boat numbers have become more frequent. We also observed that the number of anchored boats has increased over the period. These changes may be resulting in biophysical impacts that could be detrimental to conservation objectives in MPAs. This steady increase over time may cause changes in the spatial and temporal distribution of users and in their practices, thus highlighting the importance of monitoring recreational activities.
The small nation of Mauritius in the Indian Ocean, once a poor sugar plantation island, has successfully diversified and expanded its economy since independence, by attracting foreign investment in manufacturing and modern service industries. Tourism is a major part of the ‘Mauritian Miracle’; in recent years residential tourism—attracting wealthy foreigners to take up semi-permanent residence—has become a growth industry transforming coastal areas like Tamarin. Based on in-depth interviews among 17 residents of Tamarin, this paper looks at how local people perceive the changes residential tourism is causing in the local area. It appears that while the majority is positive about economic changes like more jobs and income opportunities, and to some extent about improvements in infrastructure and services, there are growing misgivings about some of the social impacts. Notably, the increasing scarcity of land and rising house prices are making it impossible for growing numbers of local people to afford a place to live, resulting in growing squatter settlements in the area. Such growing social disparities challenge the Mauritian development model and may undermine its stability. These undesirable effects call for careful management of tourism development, incorporation of sustainability standards and attention to the position of major stakeholder groups, such as local residents.
Pressure on deep-sea ecosystems continues to increase as anthropogenic activities move into ever deeper waters. To mitigate impacts on vulnerable habitats, various conservation measures exist, such as the designation of Marine Protected Areas (MPAs). So far, however, little evidence is available about their effectiveness. This paper presents a unique follow-up study assessing the status and recovery of a deep-sea fisheries closure and MPA at ~ 1000 m water depth in the NE Atlantic, eight years after designation. The Darwin Mounds cold-water coral ecosystem was discovered in 1998, and closed to all bottom contact fisheries, especially trawling, in 2003. Our repeat survey in 2011 used both high-resolution sidescan sonar data collected by Autonomous Underwater Vehicle (AUV) and video footage from a Remotely Operated Vehicle (ROV) to evaluate recovery. The results demonstrate that (1) protection was successful and fishing impact was largely avoided in the Western Darwin Mounds, which contained similar proportions of live cold-water coral occurrence in 2011 as observed in 1998–2000; however (2) the Eastern Darwin Mounds suffered severe damage pre-closure, and by 2011 showed no coral recolonisation and very little regrowth. These results are further evidence for the low resilience and slow recovery potential of deep-sea ecosystems, and underline once again the importance of the precautionary principle in deep-sea conservation.
Water clarity is a key factor for the health of marine ecosystems. The Australian Great Barrier Reef (GBR) is located on a continental shelf, with >35 major seasonal rivers discharging into this 344,000 km2 tropical to subtropical ecosystem. This work investigates how river discharges affect water clarity in different zones along and across the GBR. For each day over 11 years (2002–2013) we calculated ‘photic depth’ as a proxy measure of water clarity (calibrated to be equivalent to Secchi depth), for each 1 km2 pixel from MODIS-Aqua remote sensing data. Long-term and seasonal changes in photic depth were related to the daily discharge volumes of the nearest rivers, after statistically removing the effects of waves and tides on photic depth. The relationships between photic depths and rivers differed across and along the GBR. They typically declined from the coastal to offshore zones, and were strongest in proximity to rivers in agriculturally modified catchments. In most southern inner zones, photic depth declined consistently throughout the 11-year observation period; such long-term trend was not observed offshore nor in the northern regions. Averaged across the GBR, photic depths declined to 47% of local maximum values soon after the onset of river floods, and recovery to 95% of maximum values took on average 6 months (range: 150–260 days). The river effects were strongest at latitude 14.5°–19.0°S, where river loads are high and the continental shelf is narrow. Here, even offshore zones showed a >40% seasonal decline in photic depth, and 17–24% reductions in annual mean photic depth in years with large river nutrients and sediment loads. Our methodology is based on freely available data and tools and may be applied to other shelf systems, providing valuable insights in support of ecosystem management.
The Atlas of Ocean Wealth is the largest collection to date of information about the economic, social and cultural values of coastal and marine habitats from all over the world. It is a synthesis of innovative science, led by The Nature Conservancy (TNC), with many partners around the world. Through these efforts, we’ve gathered vast new datasets from both traditional and less likely sources.
The work includes more than 35 novel and critically important maps that show how nature’s value to people varies widely from place to place. They also illustrate nature’s potential. These maps show that we can accurately quantify the value of marine resources. Further, by enumerating such values, we can encourage their protection or enhancement for the benefit of people all around the world. In summary, it clearly articulates not just that we need nature, but how much we need it, and where.
Human-driven habitat fragmentation is cited as one of the most pressing threats facing many coastal ecosystems today. Many experiments have explored the consequences of fragmentation on fauna in one foundational habitat, seagrass beds, but have either surveyed along a gradient of existing patchiness, used artificial materials to mimic a natural bed, or sampled over short timescales. Here, we describe faunal responses to constructed fragmented landscapes varying from 4–400 m2 in two transplant garden experiments incorporating live eelgrass (Zostera marina L.). In experiments replicated within two subestuaries of the Chesapeake Bay, USA across multiple seasons and non-consecutive years, we comprehensively censused mesopredators and epifaunal communities using complementary quantitative methods. We found that community properties, including abundance, species richness, Simpson and functional diversity, and composition were generally unaffected by the number of patches and the size of the landscape, or the intensity of sampling. Additionally, an index of competition based on species co-occurrences revealed no trends with increasing patch size, contrary to theoretical predictions. We extend conclusions concerning the invariance of animal communities to habitat fragmentation from small-scale observational surveys and artificial experiments to experiments conducted with actual living plants and at more realistic scales. Our findings are likely a consequence of the rapid life histories and high mobility of the organisms common to eelgrass beds, and have implications for both conservation and restoration, suggesting that even small patches can rapidly promote abundant and diverse faunal communities.