No-take Zones Research Articles

Marine protected areas increase temporal stability of community structure, but not density or diversity, of tropical seagrass fish communities.

Marine protected areas (MPAs) have been shown to increase long-term temporal stability of fish communities and enhance ecosystem resilience to anthropogenic disturbance. Yet, the potential ability of MPAs to buffer effects of environmental variability at shorter time scales remains widely unknown. In the tropics, the yearly monsoon cycle is a major natural force affecting marine organisms in tropical regions, and its timing and severity are predicted to change over the coming century, with potentially severe effects on marine organisms, ecosystems and ecosystem services. Here, we assessed the ability of MPAs to buffer effects of monsoon seasonality on seagrass-associated fish communities, using a field survey in two MPAs (no-take zones) and two unprotected (open-access) sites around Zanzibar (Tanzania). We assessed the temporal stability of fish density and community structure within and outside MPAs during three monsoon seasons in 2014–2015, and investigated several possible mechanisms that could regulate temporal stability. Our results show that MPAs did not affect fish density and diversity, but that juvenile fish densities were temporally more stable within MPAs. Second, fish community structure was more stable within MPAs for juvenile and adult fish, but not for subadult fish or the total fish community. Third, the observed effects may be due to a combination of direct and indirect (seagrass-mediated) effects of seasonality and, potentially, fluctuating fishing pressure outside MPAs. In summary, these MPAs may not have the ability to enhance fish density and diversity and to buffer effects of monsoon seasonality on the whole fish community. However, they may increase the temporal stability of certain groups, such as juvenile fish. Consequently, our results question whether MPAs play a general role in the maintenance of biodiversity and ecosystem functioning under changing environmental conditions in tropical seagrass fish communities.

Environmental Drivers of the Spatial and Temporal Distribution of Spawning Blue Crabs Callinectes sapidus in the Western Gulf of Mexico

AbstractThe blue crab Callinectes sapidus is an economically important shellfish found in the Gulf of Mexico and elsewhere. Recent declines in abundance of this species have driven progressive management actions throughout its range, including protection of spawning females by establishing “no‐take” zones on the Atlantic coast. To date, no‐take zones have not been established in the western Gulf of Mexico, although annual closures associated with mitigation of derelict traps exist in both Texas and Louisiana. In this study, we used long‐term data acquired via fishery‐independent sampling by the Texas Parks and Wildlife Department to assess spatial and seasonal distribution of spawning females in order to inform future evaluations of no‐take areas. The presence of spawning females was modeled statistically by using water quality and spatial variables as predictors. Distance to the nearest Gulf pass was the most reliable predictor of presence, accounting for over 43% of the deviance observed in models from two independent sampling eras. Salinity (>21% of deviance) and temperature (>12% of deviance) were also reliable predictors, and the values of salinity and temperature that were associated with peak presence remained consistent over an approximately 30‐year span despite increasing mean annual values of both variables through time. Peak presence in spawning grounds now occurs in early spring (March–April), contrasting with historical peak presence in the summer (June–July). These data imply seasonal shifts in spawning behavior despite relative spatial consistency through time, suggesting that Gulf pass areas would be ideal for protection of spawning blue crabs via no‐take zones if such a measure is deemed necessary.Received March 6, 2017; accepted May 18, 2017 Published online July 19, 2017

Tourism as a driver of conflicts and changes in fisheries value chains in Marine Protected Areas

Although critical tools for protecting ocean habitats, Marine Protected Areas (MPAs) are sometimes challenged for social impacts and conflicts they may generate. Some conflicts have an economic base, which, once understood, can be used to resolve associated socioenvironmental problems. We addressed how the fish trade in an MPA that combines no-take zones and tourist or resident zones creates incentives for increased fisheries. We performed a value chain analysis following the fish supply and trade through interviews that assessed consumer demand and preference. The results showed a simple and closed value chain driven by tourism (70% of the consumption). Both tourists and local consumers preferred high trophic level species (predators), but the former preferred large pelagics (tuna and dolphinfish) and the latter preferred reef species (barracuda and snapper). Pelagic predators are caught with fresh sardines, which are sometimes located only in the no-take zone. Pelagic species are mainly served as fillet, and the leftover fish parts end up as waste, an issue that, if properly addressed, can help reduce fishing pressure. Whereas some of the target species may be sustainable (e.g., dolphinfish), others are more vulnerable (e.g., wahoo) and should not be intensively fished. We advise setting stricter limits to the number of tourists visiting MPAs, according to their own capacity and peculiarities, in order to avoid conflicts with conservations goals through incentives for increased resource use.

Mass spawning aggregation of the giant bumphead parrotfish Bolbometopon muricatum

The present study reports a previously undocumented mass spawning aggregation and group spawning phenomena of c. 1200 individual bumphead parrotfish Bolbometopon muricatum in Palau, Micronesia. Although B. muricatum are protected in Palau, it is further recommended that management strategies should consider establishment of no-take zones at B. muricatum spawning aggregations and concomitant sleeping grounds elsewhere.

Short-term impacts and value of a periodic no take zone (NTZ) in a community-managed small-scale lobster fishery, Madagascar.

The small-scale lobster fisheries of Madagascar’s impoverished southeast coast account for the majority of national catch and export, making a significant contribution to the regional economy. Data suggests catches have declined, likely due to over-exploitation. In response, the community of Sainte Luce has established a locally managed marine area (LMMA) to manage their lobster fishery, including a 13 km2 periodic no take zone (NTZ). Participatory monitoring data were used to assess compliance, identify changes in catch per unit effort (CPUE) associated with the NTZ and consider the short-term value of the NTZ. Compliance is low for measures dictated by national legislation (minimum landing size (MLS), national closed season, prohibition on landing berried females), but may be higher for those designed by the community (NTZ). Upon NTZ opening in July 2015, an estimated 435% increase in catch was observed compared with the mean for the preceding five months, a product of increased effort and significantly higher CPUE. Zero Altered Negative Binomial modelling showed CPUE was significantly higher during the NTZ opening in 2015 and in 2016 when the opening period had been moved. Whilst it is unlikely that tangible ecological benefits have accrued from NTZ operation, there have been important socio-economic effects. Specifically, there was a 33% increase in the price fishers received, a significant effect at the bottom of the value chain. Temporary increases in catch and income acted as a catalyst, engaging neighbouring communities in fishery management, resulting in two additional NTZs. Attention is drawn to the fact that current national legislation may be sub-optimal and should be reviewed. Successful management of the regional fishery will require the state and industry to support communities in adopting community-based management. The NTZ measure considered here may be an effective tool to achieve this.

Will small MPAs work?: The case of small-sized MPAs in Southern Iloilo, Philippines

Most of the marine protected areas (MPAs) in the Philippines are small-sized and community-based, and their contribution to the conservation efforts have been usually overlooked.This paper will present the results of the biological assessment study conducted in three community-based MPAs in Southern Iloilo, Philippines. Each MPA has a 2-ha no-take zone and this size is way below the recommended optimal size of 10–100 km2. Results show that fish biomass showed an overall increase of about 1–5 times. This is attributed to both an increase in abundance and in fish size. Fish in this survey conducted in 2013 were about 2.3–3.3 times the size of fish in the 2007 baseline data. Macroepifaunal abundance increased 2 to 8 times across the three MPA sites. However, live hard coral cover showed a parallel ∼40% decrease across all sites, which can be attributed to several factors.The conservation goals of these MPAs have been attained. However, the results of biological assessments still need to be correlated with a study on the socioeconomic impact of the MPAs in the community to be able to arrive at good management decisions.

The role of conservation volunteers in the detection, monitoring and management of invasive alien lionfish

Across the Caribbean, targeted fishing is gaining momentum as a cost-effective method to control invasive alien lionfish (Pterois volitans and Pterois miles) by suppressing population numbers below site-specific threshold levels i.e. a population density that is predicted to cause declines in native fish biomass. Yet in marine reserve no take zones (NTZs) or reefs at depths of >18 m) where commercial fishing is either not permitted or impractical, alternative methods of lionfish control are required. This study evaluates the potential for conservation volunteers to act as citizen scientists monitoring invasive lionfish populations and to support removal efforts in Bacalar Chico Marine Reserve (BCMR), Belize. Two underwater visual census techniques were trialled with conservation volunteers, each with associated benefits and drawbacks. A log of opportunistic lionfish sightings on SCUBA dives has been used to record sightings per unit effort (SPUE) data 2011–2015. In 2014, more rigorous lionfish focused searches (lionfish-adapted belt transects) were introduced. Opportunistic lionfish sightings contributed to a five yearSPUE dataset that suggests that lionfish population growth rate has slowed in BCMR, where a lionfish removal program was also carried out by conservation volunteers over the same timeframe. However, lionfish focused searches showed that the mean density in 2014 was high (mean = 27.05 ± 8.77 fish ha-1, 1–30 m) relative to lionfish populations in their native ranges, particularly at sites at depths > 18m (mean = 43.39 ± 13.76 fish ha-1, 18–30 m). Drawing on lessons from Belize, we discuss the potential for conservation volunteers to support invasive alien species (IAS) monitoring and control efforts in marine environments.

Contrasting patterns of residency and space use of coastal sharks within a communal shark nursery

The benefits of marine protected areas are difficult to estimate for mobile species, but their effectiveness can be increased if essential habitats, such as nursery areas, are protected. In the present study we examined movements of juvenile blacktip reef (Carcharhinus melanopterus) and sicklefin lemon (Negaprion acutidens) sharks in a coastal nursery in northern Australia. Telemetry-derived data were modelled using Brownian bridges and overlaid with maps of habitats and no-take zones. Juvenile N. acutidens were typically residents (≥30 days) of the nursery with small areas of core space use (<1.9km2), whereas juvenile C. melanopterus were non-residents (<30 days) and used larger areas (<5.6km2). Both species exhibited positive selection for sandflats and mangroves, and avoidance of deeper lagoonal and slope habitats. Monthly patterns were examined only for resident N. acutidens, and residency decreased with increasing shark length and varied seasonally for males but not females. Space use showed weak declines with increasing tidal range, and slight increases with mean air pressure, rainfall and shark length. Protecting sandflat and vegetated habitats may increase the efficacy of no-take zones for juvenile N. acutidens, because they exhibit residency and affinity to these features. Conversely, such protection will be of limited benefit for juvenile C. melanopterus, because they exhibit low residency and broader movements.

Fostering fisheries management efficiency through collaboration networks: the case of the Kanan Kay Alliance in the Mexican Caribbean

After decades of implementation of territorial use rights in fisheries (TURFs) and other fisheries management measures around the world, it is clear that monitoring their progress and results in biological and socioeconomic terms is necessary, and that involving fishers in the design and implementation will improve their likelihood of success. However, what receives less attention is the importance of multistakeholder collaboration, communication, and shared vision that increase management implementation capacity and effectiveness, while achieving an efficient use of the limited resources available to fisheries managers. Five years ago, an initiative called Kay emerged in Mexico: a voluntary, multistakeholder collaborative network formed by 40+ organizations (fishing cooperatives, government, non-governmental organizations, researchers, and philanthropic foundations). The alliance established a shared vision and collaborative work plan focused on the establishment of fish refuges (no-take zones) within TURFs across the Mexican Caribbean. The Kanan Kay Alliance offers a unique opportunity for dialogue, promotes value-added collaborative actions, and reinforces key initiatives. This collaborative model grounds management measures in a participatory and inclusive way, fostering their effectiveness and efficiency, as well as potential for reaching scale. Here we document the establishment of the Kanan Kay Alliance and provide recommendations for the replication of similar initiatives.

Five key attributes can increase marine protected areas performance for small-scale fisheries management.

Marine protected areas (MPAs) have largely proven to be effective tools for conserving marine ecosystem, while socio-economic benefits generated by MPAs to fisheries are still under debate. Many MPAs embed a no-take zone, aiming to preserve natural populations and ecosystems, within a buffer zone where potentially sustainable activities are allowed. Small-scale fisheries (SSF) within buffer zones can be highly beneficial by promoting local socio-economies. However, guidelines to successfully manage SSFs within MPAs, ensuring both conservation and fisheries goals, and reaching a win-win scenario, are largely unavailable. From the peer-reviewed literature, grey-literature and interviews, we assembled a unique database of ecological, social and economic attributes of SSF in 25 Mediterranean MPAs. Using random forest with Boruta algorithm we identified a set of attributes determining successful SSFs management within MPAs. We show that fish stocks are healthier, fishermen incomes are higher and the social acceptance of management practices is fostered if five attributes are present (i.e. high MPA enforcement, presence of a management plan, fishermen engagement in MPA management, fishermen representative in the MPA board, and promotion of sustainable fishing). These findings are pivotal to Mediterranean coastal communities so they can achieve conservation goals while allowing for profitable exploitation of fisheries resources.

Offshore marine protected areas: Divergent perceptions of divers and artisanal fishers

Thorough comprehension of the perceptions of offshore Marine Protected Areas (MPAs) by different local social actors is lacking, especially in developing countries. This study aims to analyze the perceptions and socioeconomic characteristics of divers and artisanal fishers of an offshore MPA, located in Brazilian waters. Data on the perceptions, conflicts, and management of the MPA were gathered through questionnaires and interviews with local actors. The results show that scuba divers and fishers consider the MPA to be very important for biodiversity. They also consider their collaboration in participative management to be of considerable importance, even though they do not form part of the administration. For local actors, the area helps foster the preservation of the marine environment and benefits recreational diving, tourism, and artisanal fishery in local communities. Divers and fishers use the resources and space of the offshore area differently, which results in diverging perceptions and conflicts. Divers propose restricted protection (No-Take Zones), while fishers propose that the MPA should be used exclusively by the poor local communities for artisanal fishing. Conflicts arising from inefficient public administration (lack of environmental zoning, management plans, and participative management) and illegal use of the MPA were also identified. Data stemming from the local actors themselves are central to reducing the conflicts and improving public policies on offshore marine conservation.

Monitoring the recovery of a previously exploited surf-zone fish community in the St Lucia Marine Reserve, South Africa, using a no-take sanctuary area as a benchmark

Limiting accessibility to a fishing area can reduce fishing effort effectively and may therefore promote local recovery of depleted stocks. In January 2002, beach driving was banned in South Africa, thereby reducing angler access to large areas of the coastline, particularly in less-developed areas. In November 2001 a project had been established in the St Lucia Marine Reserve, on the east coast of South Africa, to compare surf-zone fish populations inside a no-take sanctuary zone with those in an adjacent exploited area. Subsequent to the ban, the aim of the project was adapted such that surf-zone fish populations were monitored for potential recovery in what had been the exploited area, located to the north of Cape Vidal, which anglers could no longer access easily, because of the prohibition on beach driving. Standardised research fishing was conducted at two sites in the previously exploited area and two sites in the no-take sanctuary. Conventional stock-status indicators showed evidence of recovery in the four most common species caught in the previously exploited area, in terms of both abundance and biomass. Generalised additive mixed models were used to account for the influence of targeting specific species; however, subtle differences in habitat between the sampling sites, improved angling skill over time, variability in recruitment, and differential species-specific responses complicated interpretation of results. The implications of the findings are discussed in terms of the future monitoring and management of marine protected areas both within the St Lucia Marine Reserve and farther afield.

Artisanal fisheries on Kenya’s coral reefs: Decadal trends reveal management needs

Kenya’s small scale coral reef fisheries are extensively studied yet a practical understanding of the resilience and status of the main target species remains largely elusive to the manager. We combined a range of fishery and fish population descriptors to analyse Kenya’s coral reef fish and fisheries over a 20year period from the 1980s, to determine the sustainability of current fishing levels and provide recommendations for management. Fishers reported over 13 different artisanal fishing gears of which there are data for only the five widely used gears. Average catch rates declined 4-fold from the mid 1980s (13.7±1.6kg/fisher/trip) to the 1990s (3.2±0.1kg/fisher/trip) and then stabilized. Species richness in catches of these historically multi-species fisheries declined dramatically and by 2007 only 2–3 species appeared in the top bracket (65–75% by number) with Siganus sutor (African whitespotted rabbitfish) and Leptoscarus vaigiensis (marbled parrotfish) consistently being in this bracket in beach seine, gill net and basket trap catches, contributing up to a maximum of 45% and 47% of the catch, respectively. Lethrinus borbonicus dominated handline catches (50%). Relatively stable catch rates are reported from the 1990s to the mid 2000s, likely maintained by shifting proportions of species in the catches. Patterns in fish population densities over time show National Parks have helped increase densities of Lethrinidae and Haemulidae and reduced the decline in densities of Scaridae and Acanthuridae, but that National Reserves have had no positive effect. We suggest that the National Parks, which are No Take Zones (NTZs), and the fisheries regulations inside and outside of Reserves are inadequate for maintaining or restoring reef fishery target families under current levels of fishery exploitation. We propose that recruitment overfishing of several species and insufficient areas under full protection, all exacerbated by climate change, are contributing to driving Kenya’s artisanal coral reef fisheries to a tipping point. We recommend species–specific management options, changes in and enforcement of gear regulations and many more effective NTZs are needed urgently if these fisheries are to continue to provide livelihoods and food security on the Kenyan coast.

Integrating Climate Change Resilience Features into the Incremental Refinement of an Existing Marine Park.

Marine protected area (MPA) designs are likely to require iterative refinement as new knowledge is gained. In particular, there is an increasing need to consider the effects of climate change, especially the ability of ecosystems to resist and/or recover from climate-related disturbances, within the MPA planning process. However, there has been limited research addressing the incorporation of climate change resilience into MPA design. This study used Marxan conservation planning software with fine-scale shallow water (<20 m) bathymetry and habitat maps, models of major benthic communities for deeper water, and comprehensive human use information from Ningaloo Marine Park in Western Australia to identify climate change resilience features to integrate into the incremental refinement of the marine park. The study assessed the representation of benthic habitats within the current marine park zones, identified priority areas of high resilience for inclusion within no-take zones and examined if any iterative refinements to the current no-take zones are necessary. Of the 65 habitat classes, 16 did not meet representation targets within the current no-take zones, most of which were in deeper offshore waters. These deeper areas also demonstrated the highest resilience values and, as such, Marxan outputs suggested minor increases to the current no-take zones in the deeper offshore areas. This work demonstrates that inclusion of fine-scale climate change resilience features within the design process for MPAs is feasible, and can be applied to future marine spatial planning practices globally.

Exploring recreational fishers' perceptions, attitudes, and support towards a multiple-use marine protected area six years after implementation

This study assessed the acceptance and awareness of an Australian MPA (Port Stephens-Great Lakes Marine Park) post implementation by recreational fishers using the MPA, and identified factors that influenced the perception of this group towards the MPA. Recreational fishers were interviewed in a multiple-use MPA to investigate their perceptions, attitudes, and support towards the MPA six years after implementation. Almost two thirds of recreational fishers supported the MPA and had positive attitudes towards the concept of MPAs. This is a key result since a similar pre-implementation survey of recreational fishers found only 12% would support the creation of PSGLMP due to fears the MPA would negatively impact their fishing activities and ability to catch fish. However, there was a sub-group of fishers who opposed the MPA and were more inclined to have negative attitudes towards the rationale behind MPAs, despite the common perception that no-take zones were for fisheries management purposes and could increase fish stocks in the MPA. More experienced fishers were inclined to oppose the MPA, as well as fishers who believed management zones did not provide clear rules for activities, penalties for non-compliance were too harsh, or that no-take zones did not increase fish stocks. An important perceived threat to the MPA was from commercial fishing due to perceptions of over-exploitation and issues of non-compliance. In contrast, the majority of recreational fishers did not believe the collective actions of recreational fishers negatively impacted the marine environment and fish stocks, or the number of fish available for capture in the future. An improved understanding of these social aspects is important to target ongoing management in order to increase acceptance, success and long-term existence of MPAs.

Health environmental assessment of the coral reef-supporting Tamandaré Bay (NE, Brazil)

Abstract This study aimed to assess spatial and temporal ecosystem health variability of coral reefs in the Tamandare open embayment, located in Northeast Brazil, Southwest Atlantic Ocean, using water and sediment parameters and benthic foraminifera as bioindicators. Sediment samples were collected during the summer and winter of 2005 at the reef base, generally built over beachrock structures. The FORAM index (FI, a foraminiferal functional group, community-based water quality assessment), and the FORAM Stress Index (FSI, which is more related to ecological affinities than to functional groups and assesses sediment or substrata quality) together with geochemical data were interpreted using uni- and multi-variate analysis. This is the first application of FSI outside of Mediterranean waters. The dominance of the Quinqueloculina and Textularia , along with negligible numbers of living specimens, low counts of symbiont-bearing foraminifera (and thus low FI), high turbidity and high phosphorus concentrations confirm the anthropogenic influence of river inputs. All parameters suggest that the water and sediment of the Tamandare embayment are marginal for coral population settlement, although the FSI, which presents higher values at unpolluted ecosystems, suggests more sustainable conditions during summer than winter, as found for FI. The FI indication of marginal environmental health is not in agreement with the FSI and the currently stable coral population found over the underlying beachrock, especially at the established no-take zone where good conditions have been described. The central transect, influenced by the no-take zone, presents the most favorable sedimentary sector for conservation initiatives, as indicated by foraminifera and other variables, preferentially on the summer season due to low river discharge of sediments. Local scientific- and community-based coral conservation initiatives have improved ecosystem health.

Population genetic structure of the European lobster (Homarus gammarus) in the Irish Sea and implications for the effectiveness of the first British marine protected area

Levels of self-recruitment within and connectivity among populations are key factors influencing marine population persistence and stock sustainability, as well as the effectiveness of spatially explicit management strategies such as Marine Protected Areas (MPAs). In the United Kingdom (UK), Lundy Island in the Bristol Channel was designated a No-Take Zone (NTZ) in 2003 and became the UK’s first Marine Conservation Zone (MCZ) in 2009. This NTZ is expected to represent an additional resource for the sustainable management of the European lobster (Homarus gammarus) fishery. As the first step in a genetic monitoring program, this study aimed to investigate population genetic structure of lobster within and between the Irish Sea and Bristol Channel and in doing so to assess the functioning of the Lundy NTZ in the context of connectivity and other genetic parameters. Analysis of microsatellite data indicated that lobsters within the study area are genetically homogeneous and supports the view of a single panmictic population wherein the Lundy NTZ is highly connected. Levels of genetic variability were universally high with no evidence of differences for the NTZ. Furthermore, there was no evidence of recent genetic bottlenecks, and estimates of effective population sizes were infinitely large. The results suggest that if current management and breeding stock sizes are maintained genetic drift will not be strong enough to reduce neutral genetic diversity.

Bridging for Better Conservation Fit in Indonesia's Coastal-Marine Systems

Efforts to improve the fit between conservation initiatives (e.g., marine protected areas, no-take zones) and the dynamic social dimensions of coastal-marine systems remain underdeveloped. We empirically illustrate here how opportunities to enhance ‘conservation fit’ are influenced by bridging organizations that serve to (1) better align conservation initiatives with characteristics of the social context that influence conservation outcomes (e.g., institutions, culture, values, local practice), (2) foster coordinated and adaptive approaches to conservation that are reflective of multiple perspectives and knowledge, and (3) better connect people and conservation actions across jurisdictional and geographical boundaries. Qualitative methods were used in this research, including semi-structured interviews, observation of key events and meetings, and literature review. We draw from three coastal-marine conservation cases in Bali, Indonesia that exemplify different approaches to bridging for conservation fit: the Bali MPA Network, the Nusa Penida MPA, and the East Buleleng Conservation Zone. Our synthesis of these cases identifies different strategies used by bridging organizations to deal with conservation fit issues, including their capacity to integrate actors and perspectives using flexible approaches, actualize hybrid forms of decision-making, build capacity and leadership, and foster cross-scale conservation and scale-bridging social networks. We also examine the limitations of bridging organizations and offer direction for future research for coastal-marine conservation in Indonesia specifically, and the Coral Triangle region generally. More broadly, this analysis contributes new insights on emerging forms of governance designed to deliberatively fit conservation initiatives to coastal-marine social-ecological systems experiencing rapid change.

Marine systematic conservation planning for Rodrigues Island, western Indian Ocean

There is a growing number of Marine Protected Areas (MPAs) that have been selected and designed through participatory processes, following the recognition of the need to increase the involvement of local communities likely to be affected by such developments. In parallel with this shift has been the development of systematic conservation planning (SCP) tools that have increased our capacity to design MPAs to maximise biodiversity outcomes and to scale-up community-based initiatives into more comprehensive MPA networks. In Rodrigues, four Marine Reserves (no-take zones) in the north of the island were identified through participatory processes. A Marine Protected Area (multi-use), South East Marine Protected Area (SEMPA), has also been gazetted in the south of the island through a community-based approach. In order to verify and assess gaps in the stakeholder-based design, a Marine Reserve network was designed using the SCP tool Marxan using available spatial data on marine biotopes and fishing effort (FE) to achieve fisheries benefits and marine biodiversity protection. The Marxan analysis identified that only two of the four marine reserves achieve partly the objectives set and SEMPA contains planning units which can be considered as no take zones. This study shows the importance of using both stakeholder’s knowledge and scientific input for a better design of MPAs. The results from the analyses can be used by decision makers to inform decisions in a scientific way by providing a set of scenarios from the Marxan analysis.

Congruent patterns of connectivity can inform management for broadcast spawning corals on the Great Barrier Reef.

Connectivity underpins the persistence and recovery of marine ecosystems. The Great Barrier Reef (GBR) is the world's largest coral reef ecosystem and managed by an extensive network of no-take zones; however, information about connectivity was not available to optimize the network's configuration. We use multivariate analyses, Bayesian clustering algorithms and assignment tests of the largest population genetic data set for any organism on the GBR to date (Acropora tenuis, >2500 colonies; >50 reefs, genotyped for ten microsatellite loci) to demonstrate highly congruent patterns of connectivity between this common broadcast spawning reef-building coral and its congener Acropora millepora (~950 colonies; 20 reefs, genotyped for 12 microsatellite loci). For both species, there is a genetic divide at around 19°S latitude, most probably reflecting allopatric differentiation during the Pleistocene. GBR reefs north of 19°S are essentially panmictic whereas southern reefs are genetically distinct with higher levels of genetic diversity and population structure, most notably genetic subdivision between inshore and offshore reefs south of 19°S. These broadly congruent patterns of higher genetic diversities found on southern GBR reefs most likely represent the accumulation of alleles via the southward flowing East Australia Current. In addition, signatures of genetic admixture between the Coral Sea and outer-shelf reefs in the northern, central and southern GBR provide evidence of recent gene flow. Our connectivity results are consistent with predictions from recently published larval dispersal models for broadcast spawning corals on the GBR, thereby providing robust connectivity information about the dominant reef-building genus Acropora for coral reef managers.