Although larval stages ensure most connectivity between demersal fish populations, dispersal traits are increasingly less measured, despite the importance of correctly parametrizing biophysical models for spatial conservation planning. Moreover, existing data are scattered across a vast multidisciplinary literature. To address this mismatch between need and availability, we compiled data from 3,201 references into multiple datasets covering 35 key pelagic dispersal traits across fish early-life stages. We specifically compiled data on swimming speed, vertical position, and delayed settlement in demersal fishes (rafting or pelagic juveniles), as these traits exert a major yet understudied influence on dispersal scale. We systematically reported all descriptive statistics, enabling robust fitting of probability density functions to introduce particle-level variability in Lagrangian models. Overall, datasets comprise 32,988 species-level (1,709 for higher-taxon-level) records for 6,841 marine fish species worldwide, including 1,155 unpublished records (other teams), and 313 records newly collected during two fieldworks (Maldives & Guadeloupe). We also digitized 12,322 individual-level age-at-length/weight records from rearing experiments, enabling temperature-dependent growth model fitting to forecast global warming impacts on dispersal.

The yellowfin tuna (Thunnus albacares) is a widely distributed species performing long-distance migrations. Along the migratory route, individuals may use critical habitats for feeding and energy replenishment to continue their journeys; these habitats are denominated stopover sites. Such areas are poorly documented for large-bodied migratory pelagic fishes globally and remain unreported in the Atlantic. The objective of this pilot study was to identify the potential role of the Saint Peter and Saint Paul Archipelago (SPSPA) as a stopover site for yellowfin tunas caught off western Africa, using otolith chemistry. Ten pre-adult/adult yellowfin tunas were caught by purse seine fisheries along the Gulf of Guinea. Otoliths from these specimens were chemically analyzed through a core-edge transect. The SPSPA signature - characterized by high concentrations of Zn, Sr, and Ba - was examined along the otoliths. Eight out of ten yellowfin tunas exhibited coinciding peaks of these three elements in their multi-elemental profiles, suggesting passage through the SPSPA. Multivariate statistical approaches supported the hypothesis that yellowfin tunas from the Gulf of Guinea temporarily inhabited the SPSPA. Individuals arrived at the SPSPA at around 0.8 years of age and remained for roughly 5.3 months, thus categorizing the SPSPA as a 'full-service hotel' stopover. These findings suggest that the SPSPA plays a key role in the migration of the species and underscore the need for stronger enforcement to safeguard yellowfin tunas at this small, remote, geologically unique archipelago in the Atlantic Ocean.

Three key species of socio-economic importance in the coastal aquatic environments of West Africa, white grouper (Epinephelus aeneus), round sardinella (Sardinella aurita) and flat sardinella (S. maderensis) were studied to test hypotheses concerning the connectivity of these species along the coast. We characterised the elemental chemical composition of otoliths collected at seven sampling sites along the West African coastline from Mauritania to Gambia. The concentration of 12 chemical elements was analysed along a transect from the core to the edge of otolith transverse sections using LA ICP-MS. Only concentrations of Mg, Sr and Ba were high enough to be used as ratios to Ca. Mg and Sr ratios at the otolith edges highlighted a highly significant distinction between fish families, Clupeidae (sardinellas) vs. Serranidae (grouper). Discriminant analysis revealed a north-south gradient in Mg:Ca in E. aeneus, suggesting a stay at these sites along the coast, but the elements were unable to significantly discriminate the sites. Otoliths of species belonging to the same family share the same chemical pattern. A latitudinal gradient in the chemical composition of the otolith of the white grouper was observed on the coast of West Africa, recommending a local management of fisheries in each country. The common life history pattern since birth for sardinellas should be a key result for fishery management of these stocks in West Africa, with quotas for part of schools present linked with the reproduction area and period.

The Con Dao archipelago hosts the oldest MPA in Vietnam and is recognized as a regional marine biodiversity hotspot. Here, we applied environmental DNA (eDNA) metabarcoding to assess coastal fish diversity across four major habitat types: coral reefs, seagrass beds, mangroves, and a harbour in the Con Dao archipelago. Using MiFish-U 12S primers at eight stations, we detected 282 operational taxonomic units, corresponding to 144 fish taxa. Fish assemblages exhibited strong habitat structuring: community composition differed markedly among habitats, with minimal overlap. Only three species were shared across all habitats. Multivariate analyses confirmed that habitat type, rather than spatial distance among sites, was the primary driver of community differentiation. Mangrove and seagrass supported distinct assemblages that were underrepresented in existing species checklists and MPA management frameworks. Notably, eDNA detected cryptic and non-commercial species overlooked by conventional survey methods. These results substantially expand the known fish diversity of the Con Dao Archipelago and highlight the need to incorporate habitat heterogeneity, particularly non-reef ecosystems, into MPA design and monitoring. Although eDNA metabarcoding is subject to amplification biases and limited taxonomic resolution in reference databases, it offers a powerful complement to traditional surveys for characterizing under-sampled habitats.

ABSTRACT While acquiring age information is crucial for efficient stock management and biodiversity conservation, traditional aging methods fail to offer a universal, non‐invasive, and precise way of estimating a wild animal's age. DNA methylation from tissue DNA (tDNA) was recently proposed as a method to overcome these issues and showed more accurate results than telomere‐length‐based age assessments. Here, we used environmental DNA (eDNA) for the first time as a template for age estimation, focusing on the larval phase (10–24 days post‐hatch) of cultured Dicentrarchus labrax (seabass), a species of major economic and conservation interest. Using third‐generation sequencing, we were able to directly detect various modification types (e.g., cytosine and adenosine methylation in all contexts) across the whole genome using amplification‐free nanopore sequencing. However, aging sites were only present in the mitogenome, which could be a specific feature of eDNA methylation or the consequence of better DNA protection within mitochondria. By considering qualitative and quantitative information about aging sites according to an objective model selection framework, our epigenetic clock reached a cross‐validated accuracy of 2.6 days (Median Absolute Error). Such performances are higher than those of previous clocks, notably for adult seabass even when scaling MAE to the age range, which could be linked to a more dynamic epigenome during early life stages. Overall, our pilot study proposes new methods to determine the potential of eDNA for simultaneous age and biodiversity assessments, although robust validation of our preliminary results along with methodological developments are needed before field applications can be envisaged.

Most reef fishes possess an early pelagic stage that ensures the crucial role of maintaining connectivity between distant populations, as movements of older demersal stages are generally restricted. While classically considered passive, numerous studies show that most larvae largely influence dispersion scale and settlement rate by actively swimming horizontally/vertically in an oriented way during most of their pelagic phase. Laboratory measurements of active dispersal skills differ from natural behaviors of individuals observed by divers manually annotating depth and bearing every 30 s, while carrying a low‐speed flowmeter to estimate average speed. Here, we improved this protocol through the use of electronic measurement devices to achieve enhanced feasibility, replicability, efficiency, and safety. Bearing and depth could be precisely measured at high frequencies using a logger fixed on an optimized diving tray, which allowed us to reduce tracking duration from 10 to 5 min, to track more individuals. It also permitted studying in situ the temporal dynamics of vertical speed and direction changes. All further steps, including data entry, sensor calibration, circular statistics and 3D track reconstruction (Madwick filter), were automated within interactive pipelines, enabling us to obtain results within 3 h after dives during fieldwork. We conducted in situ trackings for a diversified set of species (32 per ocean) during developments in the Caribbean (Guadeloupe), before being routinely applied in the Indian Ocean (Maldives) with a majority of trackings successfully carried out (74%) despite offshore conditions. High individual orientation accuracy, combined with great swimming/sinking abilities possibly dependent on depth/current, suggests that pelagic larvae/juveniles can swim in a correlated random‐walk (CRW). This occurs even when orientation cues are too scarce for a consistent orientation among species/zones to emerge (biased CRW), marking a difference with their behavior in the coastal environment. Although biophysical models of dispersal ease the development of informed conservation strategies at large spatial scales, comparisons with genetic connectivity demonstrate that only models incorporating realistic active behaviors yield comparable outputs. Our methodological advances overcome various obstacles preventing the measurement of the parameters necessary for active models, not only for demersal fishes, but also for any small pelagic organism in any aquatic habitat.

The environmental DNA (eDNA) technique characterizes spatio-temporal fish diversity patterns along estuarine habitats, such as hard-to-reach mangroves, yet it has rarely been applied in West Africa. In this study conducted over two seasons (dry and rainy) in coastal Guinea Bissau, fish eDNA was extracted from water samples collected in three habitats with distinct human uses. These habitats included site-specific mangroves, rice fields, and transition zones sampled in three sites: Elalab in Cacheu, Malafo in Oio, and Cafine in Tombali regions. As a reference, DNA barcoding of 181 fishes resulted in 243 DNA sequences for two mitochondrial markers (139 for COI and 104 for 12S), corresponding to 76 species (69 for COI and 56 for 12S), after morpho-genetic confirmation. The metabarcoding analysis detected 49 environmental DNA-Operational Taxonomic Units (eOTUs), attributed to 15 fish orders, 29 families, 38 genera, and 32 species. Fish abundance varied between sites and seasons but not between habitats. The southern Cafine site had a significantly lower abundance during the dry season, whereas the northern Elalab site hosted relatively fewer species during the rainy season. The transition from rice fields to mangrove habitat showed a positive trend in Shannon diversity with no fish being present in the rice fields during the dry season except for Malafo. Remarkably, Coptodon cf. guineensis, Sarotherodon melanotheron and Pseudotolithus elongatus dominated the fish assemblages. This pioneering eDNA study efficiently surveyed seasonal fish diversity within Bissau-Guinean mangroves, demonstrating its potential as a novel fish monitoring tool toward effective conservation in West Africa. The coupling of these results with the human uses of mangroves should be a target in future biomonitoring initiatives in the country and the broader region.

The Saint Peter and Saint Paul Archipelago (SPSPA) is a small, remote group of islands on the Mid-Atlantic Ridge that is home to many large-bodied migratory pelagic fishes. Here, we used the yellowfin tuna (Thunnus albacares) as a model species to test the hypothesis that the SPSPA hosts subpopulations originating from other regions of the Atlantic based on the otolith chemistry. Juvenile yellowfin tunas were caught in the SPSPA over a one-year cycle, and their otoliths were analyzed using LA-ICPMS. The chemical composition of the natal origin in the otoliths was investigated and subsequently compared to that of the capture site. A K-means clustering algorithm identified two clusters for the natal origin, which differed mainly in terms of the elements Mg and Cu, indicating that two subpopulations of the yellowfin tuna occur in the SPSPA. A strong, peculiar signature was found for the SPSPA capture site, with the highest concentrations of Zn, Ba and Sr. No overlap was found between the natal origins and capture site, revealing that the SPSPA was not a spawning ground for the individuals. Zinc was the most influential element in separating groups, which may be an indicator of the passage of fish by the SPSPA. Herein, we suggest that the natal origins corresponded to the Gulf of Guinea and Southern Cape Verde Islands and that the SPSPA may serve as a stopover site during Atlantic migratory routes of subpopulations of the yellowfin tuna. Mark-recapture data from ICCAT support the suggested natal origins and migratory routes addressed here. These findings demonstrate the pivotal role of the SPSPA in the lifecycle of subpopulations of the yellowfin tuna crossing the Atlantic Ocean.

Context The invasive wels catfish is spreading to many European waterbodies and is the subject of controversy concerning its environmental impact.Aims The objective was to investigate its life-history traits (growth and reproduction) for the first time in southern France.Methods A culling action was used to assess the key life-history traits, using sections of pectoral spines for age and growth estimations, and gonad macroscopic examination for the reproduction parameters.Key results The biggest individual was a 227-cm male. The age was accurately estimated from clear translucent marks on spines, with a maximum of 13 years for both sexes. The growth appeared to be extremely rapid and was the highest at old ages recorded from both the native and the invasive distribution range. The length and age at first sexual maturity, 70.1 cm for 4-5-year-old females, and 54.1 cm for 2-3-year-old males, were the lowest recorded in Europe, indicating an early maturity.Conclusions The life-history parameters (rapid growth, early maturation, high fecundity) showed a very high potential for adaptation and colonisation.Implications The cost and management required to regulate the species appear not easily feasible, particularly when combined with its high growth rate.

Abstract Hydropower expansion is increasingly responsible for connectivity and biodiversity loss in freshwater ecosystems. The Amazon basin, which supports the highest level of freshwater biodiversity globally, faces such unplanned expansion. Here, we demonstrate and quantify the impacts of two major hydroelectric dams on the Madeira River on the trans‐Amazonian movements of one apex predatory catfish (Brachyplatystoma rousseauxii) performing the longest migration known in freshwaters. Using otolith microchemistry, we show that above the dams, the former basin‐wide homing migration between the breeding grounds in the upper Madeira and the nursery in the Amazon estuary has now been replaced by residency. We found evidence suggesting downstream migration of juvenile fish past dams into the Amazon estuary and that some of them home back to the Madeira. However, we did not find evidence that the fish homing back from the estuary can access their breeding grounds in the upper Madeira; they remain blocked below the dams. Our results provide undisputable evidence that the conservation of the species primarily requires the reestablishment of connectivity with the construction of efficient fishways.

Vietnam's oldest marine protected area, the Con Dao Archipelago, hosts a high diversity of fishes, but they are not taken into account in its management. Knowledge of the spatial and temporal diversity of fishes is critical to identify the ecological functions of protected habitats, including as nurseries and feeding grounds. One way to assess diversity is using light traps that target young fish stages.Fish were collected monthly from June 2016 to May 2017 using light traps in three main habitats: seagrass beds, coral reefs and the harbour. Morphometry and DNA barcoding were used to identify the species caught.A total of 11,293 fish were collected, of which 1,248 were barcoded and assigned to 158 species belonging to 81 genera and 34 families, evidence that coral reefs and seagrass beds in Con Dao marine protected area (MPA) are home to a highly diverse and abundant community of fish species. Species richness and Shannon diversity indices did not differ significantly among sampling sites, but both species composition and diversity indices differed in the wet and dry seasons. The abundance of fish was related to sea water temperatures, which varied significantly depending on the month. During the dry season, fish diversity peaked in April, when the water temperature was highest.Conserving fish in Con Dao MPA is important not only for the characterization of the trophic network in coral reefs and seagrass beds but also for preservation of coral reef ecosystems and endangered species. Ensuring connectivity between coral reefs and seagrass beds in Con Dao MPA would facilitate fish conservation but, at present, the MPA only focuses on protecting fragmented habitats that are home to a number of endangered mammal species. Local authorities should establish a continuum of protected areas along coastal habitats and seasonal controls on fishing as part of sustainable management of MPAs.

Life-history traits (LHT) of Oreochromis niloticus in the Sidi Mohamed Ben Abdellah reservoir (BA reservoir) and Oreochromis aureus in the Nador Channel were studied and compared with those of other populations in the world. Specimens were collected between June 2018 and June 2020. Females of both species were smaller at first sexual maturity than males (O. niloticus: 204 vs. 255 mm, O. aureus: 147 vs. 158 mm). The age of maturity for each species was estimated from seasonal otolith growth marks, based on the von Bertalanffy growth function. The asymptotic length was higher in O. niloticus (males 296 mm and females 339 mm) than in O. aureus (males 171 mm and females 169 mm). Based on a literature survey and the results of this study, the type of ecosystem (reservoir vs. river) influenced growth performance indices (φ and φ′) in both species, with reservoirs leading to a higher asymptotic length in both O. niloticus and O. aureus than rivers. Moroccan populations presented the lowest growth index in the populations assessed. These observations suggest that while both invasive species were able to colonise and adapt to their new environments, this was at the expense of limiting their growth and reducing their size at first sexual maturity.

A 13-year biomonitoring survey was carried out on the European eel, Anguilla anguilla for the first time in North Africa (Algeria) where there is a serious lack of information on the species. The study targeted specimens populating the only four sites where the species is both potentially present and legally exploited (Lake Oubeira, Lake Tonga, Mellah lagoon and Mafragh estuary). A total of 1370 individuals were sampled ranging from 17 to 113 cm in length, 19 to 2642 g in weight and 0.7 months to 6.6 years old, age being estimated from otolith growth marks. Otolith interpretation and age estimation were generally unambiguous at all four sites. According to the EELREP silvering index, the highest proportion of silver females was captured in fresh water ( 46% in Lake Oubeira and 25% in Lake Tonga), whereas a third were present in brackish water (Mafragh and Mellah). The sex ratio was in favour of females, and silver males were found to mature early (mean length 40 +/- 1 cm, mean weight 123 +/- 28 g and mean age 2 +/- 0.6 years). Growth differed at the four sites, and the growth rate was highest in Lake Oubeira and asymptotic length highest in Mellah lagoon. Metamorphosis from the yellow resident stage to the silver migrating stage occurred very early in the eels' continental life ( between 3 and 4 years of age). Results highlight rapid growth in these Algerian sites, and earlier silvering than in eels living in European waters, suggesting different life-history traits of A. anguilla in North African waters, influenced by environmental conditions.

This is a complete database of metabarcodes for fish diversity in the mangroves of Guinea-Bissau.It includes the sequences generated specifically from 49 eOTUs. Each taxa has been sequenced with a 12S marker: a 106 bp fragment using EcoPrimers by (Kelly et al., 2014; Riaz et al., 2011).The Excel file consists of three tabs:- BOLD tab: the taxonomic assignment of the obtained eOTUs- Reads tab: the reads of each eOTU per sample- Replicate tab: the characterization of each water sample

The Mekong River is one of the largest rivers in the world and hosts the second greatest fish diversity in the world after the Amazon. However, despite the importance of this diversity and its associated biomass for human food security and the economy, different anthropogenic pressures threaten the sustainability of the Mekong River and fish diversity, including the intense damming of the main river. Both the increase in salt-water penetration into the Mekong Delta and the disrupted connectivity of the river may have serious impacts on the numerous freshwater and migratory species. To evaluate the potential of an eDNA approach for monitoring fish diversity, water was sampled at 15 sites along the salinity gradient in the Mekong Delta and along 1500 km of the main stream, from Vietnam to Thailand and Laos. A total of 287 OTUs were recovered, of which 158 were identified to the species level using both reference sequences available in GenBank and references obtained locally. Agglomerative hierarchical clustering and PCA identified up to three main species assemblages in our samples. If the transition from brackish to freshwater conditions represents the main barrier between two of these assemblages, more surprisingly, the two other assemblages were observed in the freshwater Mekong, with a spatial disjunction that did not match any biogeographic ecoregion or the Khone falls, the latter thought to be an important fish dispersion barrier. Between 60% and 95% of the freshwater species were potamodromous. This pioneer eDNA study in the Mekong River at this geographical and ecological scale clearly confirmed the potential of this approach for ecological and diversity monitoring. It also demonstrated the need to rapidly build an exhaustive Mekong fish barcode library to enable more accurate species' assignment. More eDNA surveys can now be expected to better describe the ecological niche of different species, which is crucial for any models aimed at predicting the impact of future damming of the Mekong.

Knowledge of marine fish diversity remains largely incomplete in the Con Dao Archipelago, the oldest marine-protected area in Vietnam. Previous investigations of diversity established a species checklist for Con Dao but did not specifically target pre-settlement stages of reef fishes and short-life pelagic species even though they provide information on local biodiversity and on the ecological functions of their habitat. Species identification of small fishes is usually challenging, but in the present study, DNA barcode-based identification was used to update the species checklist for Con Dao marine coastal habitats. Fishes were sampled monthly over a 1-year period using light traps in coral reef, seagrass, and harbour habitats. Among a total of 11,509 individuals captured, 1248 specimens were selected for DNA barcoding analyses based on morphological differences, 1012 were successfully sequenced, and their COI sequences uploaded to the BOLD database. Among the 163 corresponding BINs, 120 were recorded for the first time in Vietnam while 40 (25%) were new to BOLD. It was impossible to assign a complete species name to 59 BINs (36%), because of gaps in the taxonomical coverage or mislabelled DNA barcodes (probably due to species misidentification). Among species observed in this study and belonging to 18 orders and 35 families, 85 and 59 were new records for Con Dao and Vietnam, respectively. The high proportion of new species records are probably related to the sampling gear used that is particularly appropriate for sampling crypto-benthic species of the families Gobiidae, Tripterygiidae, and Blenniidae. From a methodological standpoint, this study demonstrates that accuracy of the DNA barcode-based species identification can be greatly improved by careful revision of BINs, phylogenetic relationships with sibling BINs, and by using the taxonomical literature which can provide sequences of reference species.

The European eel (Anguilla anguilla) is endangered due to its peculiar life-history cycle, fishing pressure and difficulty in global population management. To improve our understanding of the population dynamics and refine conservation policies, an extended mark and recapture experiment and glass eel stocking were conducted in the River Rhône Delta (France) over 8 years. Around 1100 yellow eels were PIT-tagged and released in 2007, 2.5 kg of glass eels were released each year from 2008 to 2012, and the population was monitored using fishing between 2007 and 2015. After capture or recapture, the body parameters, sex and maturity were assessed. Age was estimated from otolith growth rings. At the end of the experiment, silver eels were between 352 and 875 mm long (age 17 to 185 months) and yellow eels between 170 and 868 mm long (age 12 to 123 months). Age estimates were validated using mark and recapture and showed 16% age underestimates and 5% inaccurate ages. The growth rates were extremely variable with lengths ranged by 2-fold at a given age. These results highlight the difficulty of eel population management, at least in the Mediterranean area.

To improve our knowledge of the migration pathway of a highly threatened fish species along the Mekong River, strontium isotope ratios (87Sr/86Sr) and 18 trace element concentrations were measured in the water and in the otoliths of an anadromous catfish, Pangasius krempfi, to infer its natal origin and potential migration pathways. Water was sampled at 18 locations along the mainstream, tributaries and distributaries of the Mekong River. To check for accuracy and precision, measurements of the 87Sr/86Sr ratios and trace element concentrations were then compared in two laboratories that use different analytical methods. Differences in trace element concentrations between locations were not significant and could not, therefore, be used to discriminate between migration pathways. However, the Mekong mainstream, tributaries and distributaries could all be discriminated using Sr isotopes. The 87Sr/86Sr profiles recorded in P. krempfi otoliths showed that there were three contingents with obligate freshwater hatching and variable spawning sites along the Mekong mainstream, from Phnom Penh (Cambodia) to Nong Khai (Thailand) or further. After hatching, the fish migrated more or less rapidly to the Mekong Delta and then settled for most of their lifetime in brackish water. Spawning habitats and migration routes may be threatened by habitat shifts and the increasing number of hydropower dams along the river, especially the contingents born above Khone Falls (Laos). The conservation of P. krempfi, as well as other migratory fish in the Mekong River, requires agreements, common actions and management by all countries along the Mekong River. This study highlighted the importance of using both Sr/Ca and 87Sr/86Sr ratios to understand life history of anadromous fishes as the 87Sr/86Sr ratio in the water was shown to be less effective than the Sr/Ca ratio in identifying movements between different saline areas.

The main life history traits of the round sardinella, Sardinella aurita Valenciennes 1847 were updated in Senegalese coastal waters, together with an evaluation of the captures over the last 33 years (19812013). In the context of global change and an increase in the average sea surface temperature along the Senegalese coast, most of the life history traits of S. aurita, such as condition factor, period of reproduction, egg sizes, relative fecundity and growth did not change significantly over the years. In contrast, the size at first sexual maturity and the absolute fecundity increased significantly, and current catches recorded less large individuals. The growth was rapid and very variable, with a longevity estimated at 6-7 years. These updated data for life history traits show that the round sardinella was fully exploited in the area, that the fishing effort for this species should be reduced, and that the minimum size (120 mm) authorized by the Senegalese fisheries code should be increased (185-200 mm) to maintain stocks along the Senegal coast. (c) 2021 Elsevier B.V. All rights reserved.

Marine protected areas (MPAs) are set up to conserve biodiversity, but their design is not always based on strictly scientific considerations. Ideally, an MPA should protect all key habitats necessary for a marine species to complete its life cycle. The identification of these key habitats is complex, especially during the early life of marine fishes. A widely distributed tropical and important low trophic-level fish species, Spratelloides delicatulus (Clupeidae), was used to evaluate the significance of various coastal habitats for its larvae and juveniles in the Con Dao Archipelago MPA in Vietnam. Early stages (larvae and juveniles) were sampled monthly over one year (June 2016 to May 2017) using light traps in three main habitats (seagrass beds, coral reefs and harbour). The species was identified using morphometry and DNA barcoding. Age and growth variables were estimated using otolith daily growth increments. A total of 3,581 fish were caught. The species was not found in captures between January and February, directly linked to the decrease in seawater temperature and was most abundant from April to June. For a subsample of 248 fish (7-38 mm standard length), ages ranged from 7 to 108 days. Captures and back-calculated birthdates using otolith daily increments showed that S. delicatulus spawns during the period of high seawater temperature, from March to October. The species colonizes all three habitats during the early stages (0-26 days old), with growth rate lowest on the seagrass beds. Nevertheless, the species occupies seagrass beds exclusively during the older stages. The conservation of seagrass beds in the Con Dao archipelago is essential for protection of juvenile stages of this species but this habitat is presently not included in the MPA patches. Establishment of a continuum of protected areas linking habitats, rather than the existing patches is needed to conserve the complete life cycle of this species in the Con Dao MPA. 1.2.3.4.5.