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Monitoring of the artificial reef fish assemblages of golfe juan marine protected area (France, North-Western Mediterranean)
Pascaline, Bodilis;Catherine, Seytre;Charbonnel, Eric;Patrice, Francour;
Brazilian Journal of Oceanography , 2011,
Abstract: artificial reefs were deployed within the golfe-juan marine protected area (alpes-maritimes coast, france, northwestern mediterranean) created in 1981. this no-take area is fully protected since its establishment, except in 2004 when some anthropic activities were, exceptionally, authorized. moreover, no park rangers to prevent poaching since 2002 occur. in order to carry out a long term monitoring of the artificial reef fish assemblages, underwater visual censuses (uvc) were carried out in 1988, 1998 and 2008, according to a traditional standardized visual census method that taken into account all fish species. the complexification of some large reefs built with wide voide spaces called bonna reefs appear to be a good solution to increase species richness and density. species richness and density of the fish assemblages showed significant increase between 1988 and 1998. however the fast increasing was stopped from 1998 and 2008 probably due to a lack of law enforcement and poaching. despite artificial reefs were deployed in mpa since at least 20 years, they did not show a real positive impact on fish assemblages. these results could be explained (i) by a lack of law enforcement patrol within the protected areas during the last decade, and (ii) by the one-year opening to fishing activities within mpa. the real effectiveness of the artificial reefs in sustaining fish assemblages is discussed and the necessity of a regular and efficient control by park rangers is highlighted.
Monitoring of the artificial reef fish assemblages of golfe juan marine protected area (France, North-Western Mediterranean)  [cached]
Bodilis Pascaline,Seytre Catherine,Eric Charbonnel,Francour Patrice
Brazilian Journal of Oceanography , 2011,
Abstract: Artificial reefs were deployed within the Golfe-Juan marine protected area (Alpes-Maritimes coast, France, Northwestern Mediterranean) created in 1981. This no-take area is fully protected since its establishment, except in 2004 when some anthropic activities were, exceptionally, authorized. Moreover, no park rangers to prevent poaching since 2002 occur. In order to carry out a long term monitoring of the artificial reef fish assemblages, underwater visual censuses (UVC) were carried out in 1988, 1998 and 2008, according to a traditional standardized visual census method that taken into account all fish species. The complexification of some large reefs built with wide voide spaces called Bonna reefs appear to be a good solution to increase species richness and density. Species richness and density of the fish assemblages showed significant increase between 1988 and 1998. However the fast increasing was stopped from 1998 and 2008 probably due to a lack of law enforcement and poaching. Despite artificial reefs were deployed in MPA since at least 20 years, they did not show a real positive impact on fish assemblages. These results could be explained (i) by a lack of law enforcement patrol within the protected areas during the last decade, and (ii) by the one-year opening to fishing activities within MPA. The real effectiveness of the artificial reefs in sustaining fish assemblages is discussed and the necessity of a regular and efficient control by park rangers is highlighted. Recifes artificiais foram implantados na área protegida Golfe-Juan (costa dos Alpes-Maritimes, Noroeste do Mediterraneo) criada em 1981. Esta área NTZ (Area de Restri o da Pesca ) é inteiramente protegida, desde seu estabelecimento, exceto em 2004, quando algumas atividades antropicas foram excepcionalmente autorizadas. Além disso, desde 2002, n o houve nenhuma patrulha florestal para impedir a ca a e pesca ilegais. . A fim realizar um monitoramento a longo prazo das assembléias artificiais dos peixes do recife, recenseamentos visuais subaquáticos (UVC) foram realizados em 1988, 1998 e 2008, de acordo com um método visual tradicional de recenseamento, que leva em considera o todas as espécies de peixes. A complexidade de alguns recifes grandes, construídos com amplos espa os vagos, chamados recifes Bonna parece ser uma boa solu o para aumentar a riqueza e a densidade das espécies. A riqueza das espécies e a densidade das assembléias de peixes mostraram um aumento significativo entre 1988 e 1998. Entretanto esse aumento rápido parou entre 1998 e 2008 provavelmente devido à falta da
Changes in Fish Assemblages following the Establishment of a Network of No-Take Marine Reserves and Partially-Protected Areas  [PDF]
Brendan P. Kelaher, Melinda A. Coleman, Allison Broad, Matthew J. Rees, Alan Jordan, Andrew R. Davis
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0085825
Abstract: Networks of no-take marine reserves and partially-protected areas (with limited fishing) are being increasingly promoted as a means of conserving biodiversity. We examined changes in fish assemblages across a network of marine reserves and two different types of partially-protected areas within a marine park over the first 5 years of its establishment. We used Baited Remote Underwater Video (BRUV) to quantify fish communities on rocky reefs at 20–40 m depth between 2008–2011. Each year, we sampled 12 sites in 6 no-take marine reserves and 12 sites in two types of partially-protected areas with contrasting levels of protection (n = 4 BRUV stations per site). Fish abundances were 38% greater across the network of marine reserves compared to the partially-protected areas, although not all individual reserves performed equally. Compliance actions were positively associated with marine reserve responses, while reserve size had no apparent relationship with reserve performance after 5 years. The richness and abundance of fishes did not consistently differ between the two types of partially-protected areas. There was, therefore, no evidence that the more regulated partially-protected areas had additional conservation benefits for reef fish assemblages. Overall, our results demonstrate conservation benefits to fish assemblages from a newly established network of temperate marine reserves. They also show that ecological monitoring can contribute to adaptive management of newly established marine reserve networks, but the extent of this contribution is limited by the rate of change in marine communities in response to protection.
Assessing Dispersal Patterns of Fish Propagules from an Effective Mediterranean Marine Protected Area  [PDF]
Antonio Di Franco, Giovanni Coppini, José Martin Pujolar, Giulio A. De Leo, Marino Gatto, Vladyslav Lyubartsev, Paco Melià, Lorenzo Zane, Paolo Guidetti
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0052108
Abstract: Successfully enforced marine protected areas (MPAs) have been widely demonstrated to allow, within their boundaries, the recovery of exploited species and beyond their boundaries, the spillover of juvenile and adult fish. Little evidence is available about the so-called ‘recruitment subsidy’, the augmented production of propagules (i.e. eggs and larvae) due to the increased abundance of large-sized spawners hosted within effective MPAs. Once emitted, propagules can be locally retained and/or exported elsewhere. Patterns of propagule retention and/or export from MPAs have been little investigated, especially in the Mediterranean. This study investigated the potential for propagule production and retention/export from a Mediterranean MPA (Torre Guaceto, SW Adriatic Sea) using the white sea bream, Diplodus sargus sargus, as a model species. A multidisciplinary approach was used combining 1) spatial distribution patterns of individuals (post-settlers and adults) assessed through visual census within Torre Guaceto MPA and in northern and southern unprotected areas, 2) Lagrangian simulations of dispersal based on an oceanographic model of the region and data on early life-history traits of the species (spawning date, pelagic larval duration) and 3) a preliminary genetic study using microsatellite loci. Results show that the MPA hosts higher densities of larger-sized spawners than outside areas, potentially guaranteeing higher propagule production. Model simulations and field observation suggest that larval retention within and long-distance dispersal across MPA boundaries allow the replenishment of the MPA and of exploited populations up to 100 km down-current (southward) from the MPA. This pattern partially agrees with the high genetic homogeneity found in the entire study area (no differences in genetic composition and diversity indices), suggesting a high gene flow. By contributing to a better understanding of propagule dispersal patterns, these findings provide crucial information for the design of MPAs and MPA networks effective to replenish fish stocks and enhance fisheries in unprotected areas.
Biodiversity and structure of rocky reef fish assemblages in the Sierra Helada Natural Park (South-western Mediterranean Sea)  [cached]
P. Arechavala-López,J. T. bayle-Sempere,P. Sánchez-Jerez,C. Valle
Arxius de Miscel-lània Zoològica , 2008,
Abstract: In the present study the fish assemblages in the rocky-bottom habitat of the Sierra Helada Natural Park (Alicante, Spain) were recorded to provide data for future evaluation of any changes induced by long-term management. Visual censuses were carried out along strip transects by Scuba diving on rocky bottoms at depths between 1 and 32 m. In the seven localities sampled, 44 species were recorded. Number of species, abundance, biomass and size structure values recorded did not show differences between high and low protection areas. Species composition was similar to other marine protected areas of the western-Mediterranean. The main differences found between localities can be attributed to the high heterogeneity and complexity of the habitat at smaller spatial scales.
Spearfishing Regulation Benefits Artisanal Fisheries: The ReGS Indicator and Its Application to a Multiple-Use Mediterranean Marine Protected Area  [PDF]
Delphine Rocklin, Jean-Antoine Tomasini, Jean-Michel Culioli, Dominique Pelletier, David Mouillot
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0023820
Abstract: The development of fishing efficiency coupled with an increase of fishing effort led to the overexploitation of numerous natural marine resources. In addition to this commercial pressure, the impact of recreational activities on fish assemblages remains barely known. Here we examined the impact of spearfishing limitation on resources in a marine protected area (MPA) and the benefit it provides for the local artisanal fishery through the use of a novel indicator. We analysed trends in the fish assemblage composition using artisanal fisheries data collected in the Bonifacio Strait Natural Reserve (BSNR), a Mediterranean MPA where the spearfishing activity has been forbidden over 15% of its area. Fish species were pooled into three response groups according to their target level by spearfishing. We developed the new flexible ReGS indicator reflecting shifts in species assemblages according to the relative abundance of each response group facing external pressure. The catch per unit effort (CPUE) increased by ca. 60% in the BSNR between 2000 and 2007, while the MPA was established in 1999. The gain of CPUE strongly depended on the considered response group: for the highly targeted group, the CPUE doubled while the CPUE of the untargeted group increased by only 15.5%. The ReGS value significantly increased from 0.31 to 0.45 (on a scale between 0 and 1) in the general perimeter of this MPA while it has reached a threshold of 0.43, considered as a reference point, in the area protected from spearfishing since 1982. Our results demonstrated that limiting recreational fishing by appropriate zoning in multiple-use MPAs represents a real benefit for artisanal fisheries. More generally we showed how our new indicator may reveal a wide range of impacts on coastal ecosystems such as global change or habitat degradation.
Dispersal Patterns of Coastal Fish: Implications for Designing Networks of Marine Protected Areas  [PDF]
Antonio Di Franco, Bronwyn M. Gillanders, Giuseppe De Benedetto, Antonio Pennetta, Giulio A. De Leo, Paolo Guidetti
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0031681
Abstract: Information about dispersal scales of fish at various life history stages is critical for successful design of networks of marine protected areas, but is lacking for most species and regions. Otolith chemistry provides an opportunity to investigate dispersal patterns at a number of life history stages. Our aim was to assess patterns of larval and post-settlement (i.e. between settlement and recruitment) dispersal at two different spatial scales in a Mediterranean coastal fish (i.e. white sea bream, Diplodus sargus sargus) using otolith chemistry. At a large spatial scale (~200 km) we investigated natal origin of fish and at a smaller scale (~30 km) we assessed “site fidelity” (i.e. post-settlement dispersal until recruitment). Larvae dispersed from three spawning areas, and a single spawning area supplied post-settlers (proxy of larval supply) to sites spread from 100 to 200 km of coastline. Post-settlement dispersal occurred within the scale examined of ~30 km, although about a third of post-settlers were recruits in the same sites where they settled. Connectivity was recorded both from a MPA to unprotected areas and vice versa. The approach adopted in the present study provides some of the first quantitative evidence of dispersal at both larval and post-settlement stages of a key species in Mediterranean rocky reefs. Similar data taken from a number of species are needed to effectively design both single marine protected areas and networks of marine protected areas.
Protection Enhances Community and Habitat Stability: Evidence from a Mediterranean Marine Protected Area  [PDF]
Simonetta Fraschetti, Giuseppe Guarnieri, Stanislao Bevilacqua, Antonio Terlizzi, Ferdinando Boero
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0081838
Abstract: Rare evidences support that Marine Protected Areas (MPAs) enhance the stability of marine habitats and assemblages. Based on nine years of observation (2001–2009) inside and outside a well managed MPA, we assessed the potential of conservation and management actions to modify patterns of spatial and/or temporal variability of Posidonia oceanica meadows, the lower midlittoral and the shallow infralittoral rock assemblages. Significant differences in both temporal variations and spatial patterns were observed between protected and unprotected locations. A lower temporal variability in the protected vs. unprotected assemblages was found in the shallow infralittoral, demonstrating that, at least at local scale, protection can enhance community stability. Macrobenthos with long-lived and relatively slow-growing invertebrates and structurally complex algal forms were homogeneously distributed in space and went through little fluctuations in time. In contrast, a mosaic of disturbed patches featured unprotected locations, with small-scale shifts from macroalgal stands to barrens, and harsh temporal variations between the two states. Opposite patterns of spatial and temporal variability were found for the midlittoral assemblages. Despite an overall clear pattern of seagrass regression through time, protected meadows showed a significantly higher shoot density than unprotected ones, suggesting a higher resistance to local human activities. Our results support the assumption that the exclusion/management of human activities within MPAs enhance the stability of the structural components of protected marine systems, reverting or arresting threat-induced trajectories of change.
Status of Coral Reef Fish Communities within the Mombasa Marine Protected Area, Kenya, more than aDecade after Establishment
Cosmas N. Munga, Mohamed O.S. Mohamed, Nassir Amiyo, Farid Dahdouh-Guebas, David O. Obura, Ann Vanreusel
Western Indian Ocean Journal of Marine Science , 2011,
Abstract: The abundance, trophic composition and diversity of fish were investigated in the Mombasa Marine Protected Area (MPA) on the Kenya coast over a period of four years (2004-2007) sixteen years after its establishment to determine its effectiveness. Fish monitoring data collected using belt transects revealed significant differences in fish abundance, distribution and composition between the MPA’s no-take area and a partially-protected area with controlled exploitation. Although seasonal variation was apparent in the trophic composition, annual differences over the four year study period were not significant. Results indicated that differences in fish composition within the MPA were due to a greater abundance of haemulids (nocturnal carnivores) and acanthurids (herbivores) in the no-take area than in the partially-protected area. Fish diversity also varied between the no-take area and the partially-protected area with a higher Shannon-Wiener diversity index associated with the no-take area. Dominance was higher in the partially-protected area than in the no-take area and was also higher during the southeast (SE) monsoon season. These results support the claim of greater effectiveness of the fully protected no-take area, compared to the partially-protected area in sustaining the rich fish community found in previous studies.
Fish with Chips: Tracking Reef Fish Movements to Evaluate Size and Connectivity of Caribbean Marine Protected Areas  [PDF]
Simon J. Pittman, Mark E. Monaco, Alan M. Friedlander, Bryan Legare, Richard S. Nemeth, Matthew S. Kendall, Matthew Poti, Randall D. Clark, Lisa M. Wedding, Chris Caldow
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0096028
Abstract: Coral reefs and associated fish populations have experienced rapid decline in the Caribbean region and marine protected areas (MPAs) have been widely implemented to address this decline. The performance of no-take MPAs (i.e., marine reserves) for protecting and rebuilding fish populations is influenced by the movement of animals within and across their boundaries. Very little is known about Caribbean reef fish movements creating a critical knowledge gap that can impede effective MPA design, performance and evaluation. Using miniature implanted acoustic transmitters and a fixed acoustic receiver array, we address three key questions: How far can reef fish move? Does connectivity exist between adjacent MPAs? Does existing MPA size match the spatial scale of reef fish movements? We show that many reef fishes are capable of traveling far greater distances and in shorter duration than was previously known. Across the Puerto Rican Shelf, more than half of our 163 tagged fish (18 species of 10 families) moved distances greater than 1 km with three fish moving more than 10 km in a single day and a quarter spending time outside of MPAs. We provide direct evidence of ecological connectivity across a network of MPAs, including estimated movements of more than 40 km connecting a nearshore MPA with a shelf-edge spawning aggregation. Most tagged fish showed high fidelity to MPAs, but also spent time outside MPAs, potentially contributing to spillover. Three-quarters of our fish were capable of traveling distances that would take them beyond the protection offered by at least 40–64% of the existing eastern Caribbean MPAs. We recommend that key species movement patterns be used to inform and evaluate MPA functionality and design, particularly size and shape. A re-scaling of our perception of Caribbean reef fish mobility and habitat use is imperative, with important implications for ecology and management effectiveness.
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