Emergent research and priorities for shark and ray conservation

Endangered Species Research, Journal Year: 2021, Volume and Issue: 47, P. 171 - 203

Published: Nov. 10, 2021

Over the past 4 decades there has been a growing concern for conservation status of elasmobranchs (sharks and rays). In 2002, first elasmobranch species were added to Appendix II Convention on International Trade in Endangered Species Wild Fauna Flora (CITES). Less than 20 yr later, 39 5 I. Despite concern, effective management remain challenged by lack data population many species, human−wildlife interactions, threats viability, efficacy approaches. We surveyed 100 most frequently published cited experts and, based ranked responses, prioritized research questions conservation. To address these questions, we then convened group 47 from 35 institutions 12 countries. The organized into following broad categories: (1) threats, (2) ecology, (3) management. For each section, sought synthesize existing knowledge, describe consensus or diverging views, identify gaps, suggest promising future directions priorities. resulting synthesis aggregates an array perspectives emergent priority

Language: Английский

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New findings into the genetic population structure of two commercially valuable and threatened sharks, Mustelus mustelus (Linnaeus, 1758) and M. punctulatus (Risso, 1827), allow refining management strategy in the Central Mediterranean Sea

Frontiers in Marine Science, Journal Year: 2025, Volume and Issue: 12

Published: Feb. 7, 2025

Elasmobranch species are the direct or accidental catch of fisheries and can have a commercial importance. In Mediterranean Sea, long-term period overfishing brought several demersal elasmobranchs to be depleted threatened by extinction, due vulnerability related their life history traits. such exploited species, information on genetic diversity connectivity is lacking should collected identify management units. this study, we focused two smooth-hound Mustelus (Linnaeus, 1758) M. punctulatus (Risso, 1827), whose abundance distribution showed decline at regional level in last century. Thanks an opportunistic yet extensive sampling, obtained largest subregional collection specimens for analysis so far. total, 86 214 mustelus were between 2016 2020 Adriatic Sea Strait Sicily. We assessed population structure typing 17 microsatellites sequencing part mitochondrial control region both species. observed substantial nuclear when accounting geographical sampling area Our results indicate presence least stocks each species: one Sicily other Sea. This study provides valuable data that integrated into broader approach define units, improving development effective strategy these Central

Language: Английский

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Barriers in a sea of elasmobranchs: From fishing for populations to testing hypotheses in population genetics

Global Ecology and Biogeography, Journal Year: 2021, Volume and Issue: 30(11), P. 2147 - 2163

Published: Sept. 7, 2021

Abstract Background The interplay of animal dispersal and environmental heterogeneity is fundamental for the distribution biodiversity on earth. In ocean, interaction physical barriers has primarily been examined organisms with planktonic larvae. Animals that lack a life stage depend active are however likely to produce distinctive patterns. Methods We used available literature population genetics phylogeography elasmobranchs (sharks, rays skates) examine how marine ecology shape genetic connectivity in animals dispersal. provide global geographical overview extracted from synthesize hydrological factors, spatial temporal scales characterize different types barriers. three most studied were analyse effect elasmobranch potential barrier type connectivity. Results characterized nine broad barriers, common being related ocean bathymetry. maximum depth occurrence , body size habitat each species as proxies potential, important predictors varying depending type. Environmental tolerance reproductive behaviour may also play crucial role However, we find studies commonly appropriate study designs based priori hypotheses test while accounting behaviour. Main conclusions Our synthesis highlights relative contribution shaping populations. new perspective interact rearrange variation illustrate methodological sources can bias detection solutions future research field.

Language: Английский

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Genetic stock structure of New Zealand fish and the use of genomics in fisheries management: an overview and outlook

New Zealand Journal of Zoology, Journal Year: 2020, Volume and Issue: 48(1), P. 1 - 31

Published: July 13, 2020

Sustainable management of wild fisheries requires accurate delineation reproductively isolated stocks to avoid depletion a commercially and ecologically important resource. However, there is still lack reliable information on stock structure for most fishery species in New Zealand. DNA markers can assist the stocks, but they also provide significant insights into other areas related genetic diversity response pressures. In this review, we first detailed summary population studies Zealand fish species, with particular focus hoki, orange roughy, snapper, ling, blue cod. We find that data uniformly lacking species. then discuss how global shift from low resolution genomics genetics has far reaching consequences sustainable our aquatic resources, by allowing us address multiple pressures are currently facing, introduce some these briefly. conclude emphasising need more systematic holistic approach use management, so best evidence available inform decisions policy makers.

Language: Английский

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Evidence of fine-scale genetic structure for reef manta rays Mobula alfredi in New Caledonia

Endangered Species Research, Journal Year: 2022, Volume and Issue: 47, P. 249 - 264

Published: Jan. 5, 2022

Our understanding of the genetic connectivity manta ray populations and drivers that shape population structure is still limited. This information crucial to identify spatial boundaries discrete guide decisions on units conserve. In this study, we used genome-wide single nucleotide polymorphisms (SNPs) assess diversity reef rays Mobula alfredi at a local scale within New Caledonia regionally in western Pacific Ocean. We provide first evidence fine-scale differentiation M. , found between 3 cleaning station aggregation sites (n = 65 samples, N 2676 SNPs, F ST 0.01, p < 0.0001). Furthermore, was evident regional individuals from 73) East Australia 19) basis statistics (3619 0.096, 0.0001) clustering algorithms, with unidirectional gene flow detected east (New Caledonia) west (Australia). These results reveal can form genetically distinct groups relatively small geographic range highlights need consider when designating management for conservation action planning.

Language: Английский

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DNA Barcode Reveals the Bycatch of Endangered Batoids Species in the Southwest Atlantic: Implications for Sustainable Fisheries Management and Conservation Efforts

Genes, Journal Year: 2019, Volume and Issue: 10(4), P. 304 - 304

Published: April 18, 2019

Today, elasmobranchs are one the most threatened vertebrate groups worldwide. In fact, at least 90% of elasmobranch species listed in International Union for Conservation Nature (IUCN) Red List, while more than 40% data-deficient. Although these vertebrates mainly affected by unsustainable fishery activities, bycatch is also major threats to sharks and batoids worldwide, represents a challenge both sustainable management biodiversity conservational efforts. Thus, this study, DNA barcode methodology was used identify composition batoid from small-scale industrial fisheries southwest Atlantic artisanal southeast Brazil. A total 228 individuals belonging four Chondrichthyes orders, seven families, 17 distinct were sequenced; among individuals, 131 belonged protected Brazil, 101 globally species, some with trade restrictions provided Appendix II Convention on Trade Endangered Species (CITES). These results highlight impacts marine unmanaged Atlantic, support implementation DNA-based methodologies species-specific identification data-poor as powerful tool improving quality fisheries’ catch statistics keeping precise records.

Language: Английский

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Genomics versus mtDNA for resolving stock structure in the silky shark (Carcharhinus falciformis)

PeerJ, Journal Year: 2020, Volume and Issue: 8, P. e10186 - e10186

Published: Oct. 21, 2020

Conservation genetic approaches for elasmobranchs have focused on regions of the mitochondrial genome or a handful nuclear microsatellites. High-throughput sequencing offers powerful alternative examining population structure using many loci distributed across and genomes. These single nucleotide polymorphisms are expected to provide finer scale more accurate level data; however, there been few genomic studies applied elasmobranch species. The desire apply next-generation is often tempered by costs, which can be offset pooling specimens prior (pool-seq). In this study, we assess utility pool-seq applying method same individual silky sharks, Carcharhinus falciformis, previously surveyed with mtDNA control region in Atlantic Indian Oceans. Pool-seq methods were able recover entire as well thousands markers. This volume sequence data enabled detection between Ocean populations, undetected previous study (inter-Atlantic SNPs FST values comparison ranging from 0.029 0.135 0.015 0.025). Our results reinforce conclusion that sampling alone may fail detect fine-scale structure, additional increase resolution some Additionally, shows costs analyzing 4,988 equivalent standard Sanger-sequenced markers become less expensive when large numbers individuals (>300) analyzed.

Language: Английский

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Commercial sharks under scrutiny: Baseline genetic distinctiveness supports structured populations of small-spotted catsharks in the Mediterranean Sea

Frontiers in Marine Science, Journal Year: 2023, Volume and Issue: 10

Published: Feb. 24, 2023

The present study, based on microsatellite markers, describes a population genetic analysis of the small-spotted catshark Scyliorhinus canicula (Linnaeus, 1758), representing one most abundant and commonly caught cartilaginous fishes in Mediterranean Sea adjacent areas. analyses were performed to unravel features (variability, connectivity, sex-biased dispersal) their relative geographic populations, both at small (around coast Sardinia, Western Sea) larger spatial scale (pan-Mediterranean level between Atlantic Ocean Sea). Individual clustering, multivariate variance rejected hypothesis homogeneity, with significant differences mainly within Eastern basins, as well NE Ocean. In detail, our results seem confirm that Strait Gibraltar could not represent complete barrier exchange individuals Sea. latter area, complex structuring for S. was found. Apart from among Western, Adriatic sites, basin catsharks around Sardinian waters are strongly differentiated all others (both eastern Tyrrhenian southernmost part Algerian basin) demographically stable. Several possible mechanisms, biological abiotic (e.g., migratory behavior, waterfronts, oceanographic discontinuities), discussed here explain peculiar characteristics. Overall, data presented, local regional level, baseline information, useful temporal monitoring assess effects or future fishing/management/conservation measures.

Language: Английский

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Multidisciplinary estimates of connectivity and population structure suggest the use of multiple units for the conservation and management of meagre, Argyrosomus regius

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: Jan. 9, 2024

Abstract Information on population structure and connectivity of targeted species is key for proper implementation spatial conservation measures. We used a combination genomics, biophysical modelling, biotelemetry to infer the Atlantic meagre, an important fisheries resource throughout its distribution. Genetic samples from previously identified spawning locations (Gironde, Tejo, Guadalquivir, Banc d’Arguin) two additional regions (Algarve Senegal) were analysed using genome-wide SNP-genotyping mitochondrial DNA analyses. Biophysical models conducted investigate larval dispersal known locations. Additionally, thirteen fish double-tagged with transmitters off Algarve (Portugal) assess movement patterns adult individuals. This multidisciplinary approach provided robust overview meagre in Atlantic. Nuclear showed clear differentiation between European African populations, significant isolation few sites. The limited level these subpopulations potentially driven by adults, capable wide-ranging movements connecting sites 500 km apart, as evidenced tagging studies, whilst inferred modelling much more (average 52 km; 95% events up 174 km). Our results show sufficient evidence structure, particularly Africa Europe but also within Europe, be managed separate stocks. considering low degree larvae connectivity, marine protected areas could crucial towards sustainability.

Language: Английский

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Taking Advantage of the Genomics Revolution for Monitoring and Conservation of Chondrichthyan Populations

Diversity, Journal Year: 2019, Volume and Issue: 11(4), P. 49 - 49

Published: March 29, 2019

Chondrichthyes (sharks, rays, skates and chimaeras) are among the oldest extant predators vital to top-down regulation of oceanic ecosystems. They an ecologically diverse group occupying a wide range habitats thus, exploited by coastal, pelagic deep-water fishing industries. most data deficient vertebrate species groups making design implementation regulatory conservation measures challenging. High-throughput sequencing technologies have significantly propelled ecological investigations understanding marine terrestrial species’ populations, but there remains paucity NGS based research on chondrichthyan populations. We present brief review current methods access genomic metagenomic from discuss applications these datasets increase our taxonomy, evolution, ecology population structures. Last, we consider opportunities challenges offered studies for management

Language: Английский

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