Effectiveness Of Marine Protected Areas Research Articles

Larval dynamics suggest phenological strategies and positive effect of marine protected areas controlling indigenous and non-indigenous crab populations

The early life of most decapod crustaceans takes place in the water column as larvae before they settle in benthic habitats. The spatial and temporal variability in the settling of larval stages offers valuable insights into the potential recruitment of natural populations. To explore this, we studied megalopa assemblages at various segments of coastline on El Hierro and Lanzarote islands, both within and outside the Marine Protected Areas (MPAs) of each island. The study spanned four consecutive oceanographic periods in the Canary Islands (NW Africa), employing light traps for sample collection. The low number of recorded species suggested that light traps exhibit selectivity, particularly for megalopae belonging to Portunidae and Grapsidae. El Hierro, which experienced warmer sea surface temperatures, displayed higher megalopa abundance values than Lanzarote and distinct larval assemblages was observed between these two islands. Similarly, we identified significant variations in abundance and species composition between stratified and mixing seasons. These seasonal differences were influenced by the dominance of Achelous hastatus, Percnon gibessi, and Cronius ruber during the stratified season. In Lanzarote, C. ruber was not recorded during the mixing season, suggesting that the colder conditions there may constrain its reproduction. Interestingly, we observed that species traditionally harvested from the intertidal zone for human consumption (Plagusia depressa) or used as bait for recreational fishing (Pachygrapsus spp. and P. gibessi) exhibited higher megalopa abundances within the MPAs. In contrast, we noted lower megalopa densities of the non-indigenous species C. ruber within the protected areas. These results indicate a positive effect of MPAs controlling indigenous and non-indigenous crab populations. Moreover, the study provides novel data, showing that light traps are suitable for monitoring the temporal occurrence, abundance, and spatial distribution of non-indigenous and commercially exploited species. This is key for adopting an ecosystem-based approach to manage marine resources.

Correspondence among multiple methods provides confidence when measuring marine protected area effects for species and assemblages

Abstract Marine protected areas (MPAs) have become a popular tool utilised across global oceans to achieve a variety of conservation goals. Because the reasons for MPA implementation can differ, it is imperative that resource managers design and execute management strategies that allow them to effectively assess MPA performance relative to the goals they set. We compared three MPA monitoring techniques commonly utilised to survey groundfish populations across different depth strata of temperate rocky reef habitat: underwater visual census (0–20 m), scientific hook and line fishing (10–50 m) and baited remote underwater video (30–100 m). We compared the strength and direction of standardised metrics, including response ratios, diversity indices and community structure, examining results through the lens of MPA performance. While each of our monitoring techniques detected similar MPA effects on groundfish biomass and density aggregated across species, MPA effects for individual species varied across methods. Each technique was shown to survey distinct groundfish community assemblages with varying levels of species diversity and richness. Synthesis and applications. While each technique was found to measure similar general trends in marine protected area (MPA) performance over time, we found compelling evidence that the utilization of multiple techniques allows managers to create the most comprehensive, effective and inclusive MPA monitoring regimes.

Extreme events delay the detection of marine protected area effects: Implications for monitoring and management

The establishment of protected natural areas worldwide has surged in the last decade, with more protected area coverage expected in the future. In the case of marine protected areas (MPAs) that prohibit fishing, there are ongoing efforts to evaluate their effectiveness in conserving fish populations. Accurate assessments of MPA effects (namely, their ability to increase fish biomass within their boundaries) are crucial to support these evaluations. However, marine ecosystems are increasingly affected by extreme events including marine heatwaves, hypoxia, storms, and epizootic outbreaks. These events can disrupt population increases within MPAs, leading to delays in expected conservation outcomes and the misperception that protection may not be effective. However, it is currently unclear to what extent disturbances could bias MPA assessments and for how long. To address this gap, we used a population model based on a common nearshore fishery species from the USA west coast (blue rockfish, Sebastes mystinus) to evaluate the detectability of MPA effects when an acute disturbance occurs within the first decade of protection. We found that detecting MPA effects with high confidence can be delayed up to 10 years following an extreme disturbance. Furthermore, the before-after sampling design (as opposed to an inside-outside or before-after-control-impact, or BACI design) is most biased by a widespread disturbance event, especially with long (>5 years) and severe disturbances (>30 % population reduction). These findings indicate that extreme events can profoundly impact MPA assessments, causing delays in recovery and detectability. Our results provide a benchmark to calibrate monitoring and management evaluations accordingly.

The ‘Paper Park Index’: Evaluating Marine Protected Area effectiveness through a global study of stakeholder perceptions

Governments around the world are increasingly committed to reaching terrestrial and marine conservation goals. But achieving such commitments is challenging, and conservation targets that are reached on paper, e.g., in terms of square kilometers protected, can be misleading. Designating Marine Protected Areas (MPAs) does not guarantee achieving marine conservation goals, and so-called ‘paper parks,’ i.e., MPAs that are legally designated but ineffective, are common. Little is known about the de facto protection status of the established MPAs and no studies or databases have considered local stakeholders’ knowledge. Using a one-question questionnaire, we collected data on local stakeholders’ perceptions of de facto fishing in their MPA from most of the world’s maritime countries. While the level of fishing effort was generally perceived to be higher in fully ‘take’ MPAs than in ‘no-take’ or multi-zone MPAs, we show that high levels of fishing also occur in MPAs that are fully protected according to MPAtlas and the IUCN, via a new ‘Paper Park Index’ (PPI), which allowed the identification of 55 likely ‘paper parks,’ i.e., Out of all 184 MPAs studied, 49 (27%) are classified as 'paper parks', of which 11 (35%) are in 'Latin America and the Caribbean', 17 (22%) in 'Indian Ocean', and 8 (16%) in 'Southeast Asia and Oceania' regions. The 11 MPAs with the highest PPI are listed and 10 of them are shown to have been already identified as not being very protective. These results highlight the importance of different stakeholders’ knowledge about the extent and type of marine protection. They also serve as an invitation to policy-makers, spatial planners, managers and the scientific community to consider local knowledge and encourage the participation of a wider group of stakeholders in policy-making, planning and management of marine spaces.

Eco-evolutionary dynamics of Atlantic cod spatial behavior maintained after the implementation of a marine reserve.

The effects of marine reserves on the life history and demography of the protected populations are well-established, typically increasing population density and body size. However, little is known about how marine reserves may alter the behavior of the populations that are the target of protection. In theory, marine reserves can relax selection on spatial behavioral phenotypes that were previously targeted by the fishery and also drive selection in favor of less mobile individuals. In this study, we used acoustic telemetry to monitor the individual spatial behavior of 566 Atlantic cod (Gadus morhua Linnaeus, 1758) moving within a marine reserve and a control site in southern Norway, starting 1 year before the implementation of the marine reserve and lasting up to 9 years after. Following a before-after-control-impact approach, we investigated changes in (1) survival, (2) selection acting on behavioral traits, and (3)mean behavioral phenotypes, after the implementation of the marine reserve. We focused on three behavioral traits commonly used to describe the mobility of aquatic animals: home range size, depth position, and diel vertical migration range. Survival increased after reserve implementation, but contrary to our expectations, it subsequently decreased to preprotection levels after just 3 years. Further, we found no significance in selection patterns acting on any of the three behavioral traits after reserve implementation. Although some changes related to water column use (the tendency to occupy deeper waters) were observed in the marine reserve after 9 years, they cannot unequivocally be attributed to protection. Our results show that survival and behavioral responses to marine reserves in some cases may be more complex than previously anticipated and highlight the need for appropriately scaled management experiments and more integrated approaches to understand the effects of marine protected areas on harvested aquatic species.

Effects of marine protected areas on fish communities in a hotspot of climate change and invasion

The positive ecological effect of fully protected Marine Protected Areas (MPAs) on fish populations has been widely explored. Key indicators of fully protected MPAs effectiveness include an increase in biomass, density, and body size of commercially exploited large fishes. Fully protected MPAs are also hypothesized to be more resilient to both marine invasions and ocean warming, but this has seldom been tested. The eastern Mediterranean (Levantine) basin is the warmest region in the Mediterranean. Moreover, this region is the front-line of biological invasion from the Red Sea via the Suez Canal. Thus, MPAs in this region are faced with both high numbers of exotic species and warm temperatures. Assessing the performance of MPAs in this region is important for understanding their effectiveness under adverse future conditions worldwide. The ecological effectiveness of four MPAs along the Levantine Israeli coast was followed along over five years and compared with adjacent fished control area. Sampling was conducted in both old (>20 years of enforcement) and young MPAs, which only recently became fully protected. Using SCUBA diving surveys, 978 visual transects were performed to assess fish abundance, size, and diversity. We found clear indications for the benefits of the MPAs as evident by higher numbers of large fishes and groupers within protected areas. In the largest and oldest MPA we also found higher total and commercial fish biomass. In addition, we show a clear increase in the number of groupers over time, both within and outside MPAs, that may be associated with increased fishing regulation and enforcement. We found no clear evidence for a lower number of exotic species within MPAs. Our findings suggest that restrictions on recreational and commercial fishing within MPAs benefit the recovery of fish populations even in warm waters and when faced with marine invasions, and that the effectiveness of MPAs may be evident after only a few years of protection.

Effects of marine protected areas under different management regimes in a hot spot of biodiversity and cumulative impacts from SW Atlantic

Marine protected areas (MPAs) represent a useful tool for resource management, as well as to conserve and/or restore biological communities. The level of protection is key factor influencing the marine biodiversity, where a more enforced protection is expected to drive positive outcomes. In 2008, a large MPAs network (∼11,380 km 2) was established in one of off the most populated and industrialized areas in the world (i.e., São Paulo State coast, southeast Brazil). Given many goods and services provided by marine ecosystems, this MPA network represents the most challenging marine conservation initiative in Brazil. Harboring​ areas with different socio-ecological contexts and management regimes, this MPA network provides a unique opportunity to investigate the effects of cumulative impacts. We contrasted the biomass and size structure of reef fish in three subtropical islands under different levels of enforcement. We analyzed the influence of variables as island size, benthic cover, depth, topographic complexity, wave exposure, and protection level on the biomass of reef fish assemblages. Protection level was the main attribute responsible to explain the high biomass of fish target species and small territorial herbivores. In sites sheltered from the waves, the biomass of groupers was ∼1600% higher within enforced area than that from open-access area. Beyond the idea of positive effects of enforcement on reef fish biomass and size, we add evidences that even under multiple stressors, the area-based management is still a strong tool to marine conservation.

Biodiversity protection in the 21st century needs intact habitat and protection from overexploitation whether inside or outside parks

Biodiversity protection in the 21st century needs intact habitat and protection from overexploitation whether inside or outside parks

No effect of marine protected areas on managed reef fish species in the southeastern United States Atlantic Ocean

Marine protected areas (MPAs) have been recommended as an essential conservation tool for ecosystems and fisheries, with MPA coverage increasing four-fold globally since 2000. Despite the increased usage of MPAs, empirical results and scientists are divided on the effectiveness of MPAs to reach their conservation and management goals. In 2009, the South Atlantic Fishery Management Council established eight deep-water partially-protected MPAs off the southeast United States (SEUS) Atlantic coast with the goal of protecting long-lived, deep-water, reef-associated fishery species. Data collected during fish trapping from 2000 to 2018 as part of a fisheries-independent survey were used to evaluate the impacts of protection on a subset of fish species in three of these MPAs. There was a modest positive shift to larger fish observed in two of the MPAs and to older fish for one species, Pagrus pagrus (Linnaeus, 1758), in one of the MPAs relative to adjacent fished areas; however, there was either no change or a decrease in managed reef fish abundance in each MPA relative to adjacent fished areas. Based on these metrics, it does not appear that the SEUS MPAs have yet been effective at protecting managed reef fish species. Given that these MPAs have low enforcement, future assessments should examine compliance within the SEUS MPAs to determine if lack of success is due to illegal fishing, species examined, or MPA design before making a final determination if deep-water MPAs are an effective strategy for fisheries managers in the SEUS.

Evaluating the social and ecological effectiveness of partially protected marine areas.

Marine protected areas (MPAs) are a primary tool for the stewardship, conservation, and restoration of marine ecosystems, yet 69% of global MPAs are only partially protected (i.e., are open to some form of fishing). Although fully protected areas have well‐documented outcomes, including increased fish diversity and biomass, the effectiveness of partially protected areas is contested. Partially protected areas may provide benefits in some contexts and may be warranted for social reasons, yet social outcomes often depend on MPAs achieving their ecological goals to distinguish them from open areas and justify the cost of protection. We assessed the social perceptions and ecological effectiveness of 18 partially protected areas and 19 fully protected areas compared with 19 open areas along 7000 km of coast of southern Australia. We used mixed methods, gathering data via semistructured interviews, site surveys, and Reef Life (underwater visual census) surveys. We analyzed qualitative data in accordance with grounded theory and quantitative data with multivariate and univariate linear mixed‐effects models. We found no social or ecological benefits for partially protected areas relative to open areas in our study. Partially protected areas had no more fish, invertebrates, or algae than open areas; were poorly understood by coastal users; were not more attractive than open areas; and were not perceived to have better marine life than open areas. These findings provide an important counterpoint to some large‐scale meta‐analyses that conclude partially protected areas can be ecologically effective but that draw this conclusion based on narrower measures. We argue that partially protected areas act as red herrings in marine conservation because they create an illusion of protection and consume scarce conservation resources yet provide little or no social or ecological gain over open areas. Fully protected areas, by contrast, have more fish species and biomass and are well understood, supported, and valued by the public. They are perceived to have better marine life and be improving over time in keeping with actual ecological results. Conservation outcomes can be improved by upgrading partially protected areas to higher levels of protection including conversion to fully protected areas.

The effects of marine protected areas on populations of commercial reef fishes in Moorea, French Polynesia

While marine protected areas (MPAs) have been internationally recognized as an effective resource management technique, many MPAs worldwide are not fulfilling their conservation goals and are under review: as is the case in Moorea, French Polynesia. Although a system of 8 MPAs has been in effect for ~15 years on the island, adherence of fishers to the boundaries and public support for the current management plan (PGEM) is spotty. This study uses underwater surveys of 9 taxa of reef fish to evaluate how effective fishing restrictions in Moorea, French Polynesia are for conserving populations of commonly targeted fish in the backreef habitat. The current study investigates the effectiveness of Moorea's MPAs on conserving populations of commercial reef fish by measuring abundance and size structure of commonly targeted fish just in 2019, and long-term biomass monitoring data from 2004 through 2018. There were increases in commercial reef fish abundance in MPAs for most taxa and there were differences in size distributions for 3 of the taxa between MPAs and fished control sites in 2019. Generally, more individuals of larger size classes were present in MPA sites compared to fished control sites. However, time series data from the last 15 years revealed no significant increases in harvested fish biomass in protected areas relative to fished control sites in the backreef habitat. Increased efforts in policy enforcement, community awareness, and biological monitoring are required at Moorea's MPAs and others worldwide to ensure protected areas truly are effective.

The effects of marine protected areas on ecosystem recovery and fisheries using a comparative modelling approach

Abstract The overexploitation of many marine resources and ecosystems calls for the development and implementation of measures to support their recovery and conservation. The potential contributions to support fisheries and ecosystem recovery were assessed at the local level of the three multiple‐use marine protected areas (MPAs) of Cerbère‐Banyuls, Medes Islands, and Cap de Creus, located in the north‐western Mediterranean Sea. For each MPA, a food‐web model accounting for each protection level (PL) was developed: the fully protected area (FPA), the partially protected area (PPA) and the unprotected area (UPA) surrounding the MPA. Using the resulting nine food‐web models, the ecosystem structure and functioning of each PL were compared and characterized, differences and similarities within and among the three MPAs were assessed, and ecosystem response to full protection was evaluated for the three MPAs. Differences in terms of ecosystem structure and functioning were found among PLs. Overall, FPAs presented the most positive effect of protection in terms of ecosystem structure and functioning, followed by PPAs. However, the effects of protection on neighbouring UPAs were hardly noticeable. Similarities between Cerbère‐Banyuls and Medes Islands MPAs were observed, while Cap de Creus MPA showed the least benefits from protection overall. These results are likely to be due to similarities in the configuration of the protected areas, the levels of enforcement and compliance, and the impact of recreational and small‐scale fisheries allowed in the PPAs and UPAs. This study illustrates that well‐enforced Mediterranean MPAs, even when small, can yield local positive impacts on the structure and functioning of marine ecosystems that can contribute to support local fisheries.

The protection effects of marine protected areas on exploited molluscs from an oceanic archipelago

Abstract Limpets are one of the most successful intertidal algal grazers in the north‐eastern Atlantic. They provide valuable ecosystem services, playing a pivotal role in maintaining rocky shore ecological balance and have an important economic value, being subject to high levels of exploitation in several oceanic archipelagos. Limpets represent one of the most profitable economic activities of small‐scale fisheries in the Madeira archipelago. However, limpets are extremely vulnerable to anthropogenic impacts, such as overharvesting, habitat fragmentation, and pollution. The protection effects and the effectiveness of marine protected areas (MPAs) on the population dynamics of two historically highly exploited limpet species, Patella aspera and Patella candei, were analysed through a comparative study of size, reproduction, and biomass in the Madeira archipelago. The effects of protection from MPAs on limpet populations resulted in a differential increase on size at first maturity, shell size, and capture per unit effort according to the degree of protection. Old and enforced MPAs showed the best‐preserved limpet populations in the study area, and both variables (age and enforcement) best explained the observed variability among the MPAs studied. A thorough and multidisciplinary study is necessary to obtain a reliable picture of commercial stocks of the two targeted species (P. aspera and P. candei). Genetic analysis and studies on the food source of limpets may shed light to develop integrative conservation strategies.

Limited effects of marine protected areas on the distribution of invasive species, despite positive effects on diversity in shallow-water marine communities

Marine protected areas (MPAs) can be an effective tool for the conservation and management of marine coastal habitats. MPAs have been shown to halt habitat degradation, enhance the biomass of exploited species and diversity in general. Yet, we still know little about its role in halting the spread of non-native species. In this study, we assessed the role of MPAs in the structure of shallow subtidal communities around Sao Miguel Island, in general, and particularly on distribution of the two species of genus Asparagopsis: A. armata and A. taxiformis. In the Azores, the former is a well-established invasive species, whereas the status of A. taxiformis is still questionable. Overall, there was a significant greater diversity in terms of both species richness and number of macroalgal functional groups within MPAs. However, when considering the relative abundance of the various macroalgal functional groups, or the assemblage as a whole (multivariate analysis), there was no significant difference between areas within and outside MPAs. The cover of A. taxiformis was significantly greater within MPAs but not its biomass, whereas no significant variation was observed for A. armata. Overall, results suggest that surveyed MPAs had a positive effect on the diversity of shallow-water macroalgal communities. However, they have a limited role on the distribution of both Asparagopsis spp. and negligible effects when considering the relative abundances of macroalgal functional groups.

Marine protected areas modulate habitat suitability of the invasive round goby (Neogobius melanostomus) in the Baltic Sea

Biological invasions are one of the leading causes of biodiversity loss worldwide. Given that eradication of invasive species is not usually a practical option, conservationists may attempt to limit their impacts through the designation and management of protected areas. Here, we investigate the effect of marine protected areas on the habitat suitability of an invasive species, the round goby (Neogobius melanostomus). By modelling its environmental niche space in the Baltic Sea, we demonstrated that gobies prefer shallow, warmer waters, sheltered from significant wave action. They are more likely to be found near areas of intense shipping, this being their primary method of long-distance dispersal. Comparison of the goby's occurrences inside/outside protected areas indicated that suitable habitats within protected areas are more resistant to the round goby's invasion compared to adjacent unprotected areas, however the opposite is true for suboptimal habitats. This has important ecosystem management implications with marine conservation areas providing mitigation measures to control the spread of round goby in its optimal habitats in the Baltic Sea environment. Being subjected to reduced human impacts, native species within protected areas may be more numerous and diverse, helping to resist invasive species incursion.

Community-wide effects of protection reveal insights into marine protected area effectiveness for reef fish

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 620:99-117 (2019) - DOI: https://doi.org/10.3354/meps12970 Community-wide effects of protection reveal insights into marine protected area effectiveness for reef fish E. R. Heyns-Veale1,2,*, A. T. F. Bernard2,3, A. Götz1,4, B. Q. Mann5, J. Q. Maggs5, M. K. S. Smith6 1South African Environmental Observation Network (SAEON), Elwandle Node, NMMU Ocean Sciences Campus, 4 Gomery Avenue, Summerstrand, Port Elizabeth, 6031, South Africa 2South African Institute for Aquatic Biodiversity (SAIAB), Somerset Street, Makhanda 6140, South Africa 3Department of Zoology and Entomology, Rhodes University, Makhanda 6140, South Africa 4Zoology Department, Nelson Mandela University, Port Elizabeth 6031, South Africa 5Oceanographic Research Institute, PO Box 10712, Marine Parade, Durban 4056, South Africa 6Rondevlei Scientific Services, South African National Parks, Sedgefield 6573, South Africa *Corresponding author: elodieheyns@gmail.com ABSTRACT: Marine protected areas (MPAs) are not designed the same, nor are they equally effective. Efficacy of MPAs is frequently gauged by measuring the direct ecological responses of fish communities. However measuring the indirect, or knock-on effects from protection can provide additional insight into MPA effectiveness at the community level. Here we applied trait-based and community analyses to investigate MPA effectiveness by evaluating both direct and indirect effects of protection on fish assemblages using baited remote underwater stereo-video data from inside and outside 5 no-take MPAs along the South African coastline. The trait-based analyses indicated the presence of a significant overall direct effect (increased abundance of mature individuals targeted by fisheries) and indirect effects (reduction of the abundance of species not targeted by fisheries) inside MPAs, and highlighted that fish maturity is an essential trait to incorporate when assessing direct effects of protection. However, investigation of the species data of the individual MPAs showed positive reserve effects at the community level (both direct and indirect effects) in only 3 MPAs. For the most part these results conform with current theories on the factors that contribute to MPA effectiveness. Yet, one old, large and isolated no-take MPA showed no direct effects of protection, which is attributed to the lack of adequate offshore reef habitat throughout this MPA. While these results support the value of MPAs as ecosystem management tools, they highlight the need for appropriate site selection when designing MPAs. KEY WORDS: MPA effectiveness · NEOLI · Stereo-BRUVs · Functional entities · Life-stage · Ecological isolation Full text in pdf format Supplementary material PreviousNextCite this article as: Heyns-Veale ER, Bernard ATF, Götz A, Mann BQ, Maggs JQ, Smith MKS (2019) Community-wide effects of protection reveal insights into marine protected area effectiveness for reef fish. Mar Ecol Prog Ser 620:99-117. https://doi.org/10.3354/meps12970 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 620. Online publication date: June 18, 2019 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2019 Inter-Research.

Well-being outcomes of marine protected areas

Marine protected areas are advocated as a key strategy for simultaneously protecting marine biodiversity and supporting coastal livelihoods, but their implementation can be challenging for numerous reasons, including perceived negative effects on human well-being. We synthesized research from 118 peer-reviewed articles that analyse outcomes related to marine protected areas on people, and found that half of documented well-being outcomes were positive and about one-third were negative. No-take, well-enforced and old marine protected areas had positive human well-being outcomes, which aligns with most findings from ecological studies. Marine protected areas with single zones had more positive effects on human well-being than areas with multiple zones. Most studies focused on economic and governance aspects of well-being, leaving social, health and cultural domains understudied. Well-being outcomes arose from direct effects of marine protected area governance processes or management actions and from indirect effects mediated by changes in the ecosystem. Our findings illustrate that both human well-being and biodiversity conservation can be improved through marine protected areas, yet negative impacts commonly co-occur with benefits. While marine protected areas are key for supporting biodiversity and coastal communities, the outcomes can be, and can be perceived, as a mixed bag. Synthesizing research from 118 articles, this Analysis draws broad insights about both the effects of marine protected areas as well as which aspects remain understudied.

Strengths and limitations of before–after–control–impact analysis for testing the effects of marine protected areas on managed populations

AbstractMarine protected areas (MPAs) are a common management strategy for conserving marine resources, but it can be challenging to evaluate their effectiveness for meeting management objectives. Measuring the effectiveness of MPAs is particularly challenging in dynamic and changing environments where other management approaches are simultaneously implemented. Before–after–control–impact (BACI) analysis is a tool that offers a simple and robust design for evaluating complex effects. However, design and interpretation of a BACI analysis is not always straightforward. The goal of this study was to explore the potential for BACI to evaluate MPA performance in a system simultaneously impacted by other management measures and environmental change. We develop a typology of interpretations of BACI results based on the main and interaction effects of the model, categorized by the extent to which dynamics inside and outside of the MPA are independent. Furthermore, we examine how decisions about the spatial and temporal design of the study, and the focal species and response variables, can determine which outcomes from within the typology are evident through BACI applications to New England groundfish area closures. We identify strengths and limitations of the BACI approach and demonstrate that BACI is a valuable but imperfect tool for evaluating MPAs.

Effect of marine protected areas on distinct fish life-history stages

The role of Marine Protected Areas on distinct life stages of Mediterranean reef fish species (classified on the basis of their economic value and mobility categories) was assessed in a network of marine reserves in SE Spain. Only abundance and biomass of adult of both commercial and demersal species were positively affected by protection. Gradients across reserve boundaries (as a clue to the occurrence of spillover) were observed for fish abundance but not for biomass, indicating a protected fish assemblage with a predominance of small-sized individuals. Also, post-larvae of commercial species were negatively related to protected zones. Active selection of settlement preferred habitats, larval accumulation favoured by the geomorphological configuration of the coast or mixed effects has been proposed as possible explanations. Juveniles showed high spatial variability resulting in a lack of response to fishing protection measures. We highlight the need of including early life stages and overall suitable habitats for them when designing MPA networks due to the crucial importance of these stages to successful fulfillment of MPA objectives.

Effects of marine protected areas on coastal fishes across the Azores archipelago, mid-North Atlantic

Marine reserves across different eco-regions and habitats have proven to benefit exploited fish populations within their borders. There is also mounting evidence, mostly from continental shelf regions, that such positive effects will depend on the species ecological traits (e.g. mobility) and on the characteristics of the reserves (e.g. design, age and enforcement). This study examines the effects of protection on commercial coastal fishes with different ecological traits from three marine reserves with distinct habitats (coastal vs. offshore reefs), protection regime (legal vs. voluntary, partial vs. total protection) and age (8, 15 and 26 years old) across the oceanic archipelago of the Azores, mid North Atlantic. Overall, positive effects of protection on fish abundance or individual size were limited to species of larger maximum size and lower mobility in reserves with higher compliance levels. This result agrees with many studies elsewhere showing that reserves of small size and/or insufficient compliance do not provide adequate protection to the entire fish community, limiting their contribution to manage fisheries and conserve biodiversity. That might very well be the case of Azorean marine reserves but a more conclusive result will require testing the effects of protection on larger, well enforced reserves, which still do not exist in the region. There was also a clear influence of depth in commercial fish distribution and a common preference for substrates of higher complexity across ecological traits. Combined, these results highlight the need to include complex reef structures, diverse coastal habitats and larger areas when designing multispecies marine reserves and stress that an appropriate management regime is crucial for the success of the reserve, in particular to promote compliance.