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- Global population genetic structure of the sequential hermaphrodite, dusky grouper (Epinephelus marginatus)Publication . Vaini, Jussara Oliveira; Domingues, Rodrigo Rodrigues; Ferrette, Bruno Lopes da Silva; Hallerman, Eric M.; Mota, Kenneth Gabriel; Barreiros, João P.; Hilsdorf, Alexandre Wagner SilvaThe dusky grouper Epinephelus marginatus is a large epinephelid species that occurs in the eastern and south-western Atlantic and western Indian Oceans. Late maturity, protogynous hermaphroditism, site fidelity, and overfishing have all contributed to its demographic decline. Connectivity and demography within a broad sampling of dusky grouper populations throughout its distribution were assessed. To do so, genetic variation at 11 polymorphic microsatellite loci and a partial sequence of the mitochondrial control region (mtCR) were evaluated. Two major mtCR lineages with a sequence divergence of 1.6% were found. The magnitude of genetic differentiation for mtCR among north and south Atlantic and Indian Ocean populations was high, with ΦST = 0.528. DEST and results of discriminant analysis of principal component revealed significant microsatellite genetic differentiation between all collection areas. Significant pairwise DEST showed moderate (0.084) to very great (0.603) differentiation. The effective population size was low for all localities, ranging between 25 (Azores Archipelago) and 311 (Rio Grande do Sul). The overall effective population size was estimated as 299 (confidence interval = 215–412), and there was no evidence of strong or recent bottleneck effects. Local and regional genetic structuring among dusky grouper populations is the consequence of the species' site fidelity, distribution across multiple oceanographic boundaries, and probably also of sequential hermaphroditism that contributes to the intensity of random genetic drift. The spatial pattern of genetic structuring of dusky groupers is such that fisheries management and conservation of population genetic integrity will have to be pursued at the local and regional scales.
- Occurrences of pinnipeds (Carnivora, Phocidae) in the Azores archipelago (Portugal)Publication . Barcelos, Luis M. D.; Barreiros, João P.An inventory of historical and actual occurrences of pinnipeds in the Azores archipelago. The data used come from Silva et al. (2009) and from RACA - Rede de Arrojamentos de Cetáceos dos Açores (RACA-DRAM-RAA).
- Pinniped (Carnivora, Phocidae) occurrences in the Azores Archipelago (NE Atlantic)Publication . Barcelos, Luis M. D.; Barreiros, João P.BACKGROUND: The last Pinniped species update was in 2010, as part of the list of the terrestrial and marine biota from the Azores. This list includes a chapter dedicated to marine mammals, based on previously published bibliography. NEW INFORMATION: No new species were added since that list was published. However, there were new occurrences since the last update.
- Updated checklist of Azores Chondrichthyes (Vertebrata: Gnathostomata)Publication . Barcelos, Luis M. D.; Azevedo, José M. N.; Barreiros, João P.Chondrichthyes are commonly known as cartilaginous fishes and includes chimeras, sharks and rays. They can be found from the cold deep-sea to subtropical and tropical waters (Greemberg 2009). Sharks and rays have a great recreational and ecological interest (Vieira et al. 2020); however, many species worldwide are declining due to global overfishing (Worm et al. 2013). The total estimation for risk extinction, according to the IUCN Red List criteria, indicates that a quarter of all shark and ray species are threatened (Dulvy et al. 2014). The first comprehensive chondrichthyan checklist for Azores was published over 20 years ago by Santos et al. (1997). After that, some updates were made, most of them integrated in marine fish or biodiversity lists (e.g. Porteiro et al. 2010). In the meantime, new publications have emerged regarding new records (e.g. Catarino et al. 2020) or with new information on species already recorded for Azores (e.g. Das and Afonso 2017, Barcelos et al. 2018). The present work gives taxonomic updates and information regarding the conservation status (IUCN) for all chondrichthyan species from the Azores' EEZ. This is the first complete and updated list of chondrichthyans that can be found in the GBIF online platform (Barcelos et al. 2020).
- Valuable but vulnerable : Over-fishing and under-management continue to threaten groupers so what now?Publication . Mitcheson, Yvonne Sadovy de; Linardich, Christi; Barreiros, João P.; Ralph, Gina M.; Aguilar-Perera, Alfonso; Afonso, Pedro; Erisman, Brad E.; Pollard, David A.; Fennessy, Sean T.; Bertoncini, Áthila A.; Nair, Rekha J.; Rhodes, Kevin L.; Francour, Patrice; Brulé, Thierry; Samoilys, Melita A.; Ferreira, Beatrice P.; Craig, MatthewAmong threats to marine species, overfishing has often been highlighted as a major contributor to population declines and yet fishing effort has increased globally over the past decade. This paper discusses the decadal reassessment of groupers (family Epinephelidae), an important and valuable group of marine fishes subjected to high market demand and intense fishing effort, based on IUCN criteria. Allowing for uncertainty in the status of species listed as Data Deficient, 19 species (11.4%) are currently assigned to a “threatened” category. This first reassessment for a large marine fish taxon permits an evaluation of changes following the original assessments, provides a profile of the current conservation condition of species, identifies the challenges of assessing conservation status, and highlights current and emerging threats. Measures needed to reduce threats and lessons learned from conservation efforts are highlighted. Present threats include intensifying fishing effort in the face of absent or insufficient fishery management or monitoring, growing pressures from international trade, and an inadequate coverage in effectively managed, sized, or located protected areas. Emerging threats involve expansion of fishing effort into deeper waters and more remote locations, shifts to previously non-targeted species, increases in the capture, marketing and use of juveniles, growing demands for domestic and international trade, and, potentially, climate change. Those species most threatened are larger-bodied, longer-lived groupers, most of which reproduce in spawning aggregations.
- Updated checklist of Azores Actinopterygii (Gnathostomata: Osteichthyes)Publication . Barcelos, Luis M. D.; Azevedo, José M. N.; Barreiros, João P.BACKGROUND Since the first published comprehensive checklist of Azorean fishes - covering the whole Exclusive Economic Zone (EEZ) region - several new records have been published and an updated checklist published in 2010. This new dataset covers all confirmed species of actinopterygians for the Azorean EEZ. NEW INFORMATION In this update, we made corrections to the previous checklists, updated the taxonomy according to the most recent bibliography and added two new species to the Azorean Actinopterygii checklist.
- Population expansion of the invasive Pomacentridae Chromis limbata (Valenciennes, 1833) in Southern Brazilian coast: long-term monitoring, fundamental niche availability and new recordsPublication . Anderson, Antônio B.; Silva, Jodir Pereira da; Sorvilo, Raquel; Francini, Carlo Leopoldo B.; Floeter, Sergio R.; Barreiros, João P.Human-mediated species invasions are recognized as a leading cause of global biotic homogenization and extinction. Studies on colonization events since early stages, establishment of new populations and range extension are scarce because of their rarity, difficult detection and monitoring. Chromis limbata is a reef-associated and non-migratory marine fish from the family Pomacentridae found in depths ranging between 3 and 45 m. The original distribution of the species encompassed exclusively the eastern Atlantic, including the Azores, Madeira and the Canary Islands. It is also commonly reported from West Africa between Senegal and Pointe Noire, Congo. In 2008, vagrant individuals of C. limbata were recorded off the east coast of Santa Catarina Island, South Brazil (27° 41' 44″ S, 48° 27' 53″ W). This study evaluated the increasing densities of C. limbata populations in Santa Catarina State shoreline. Two recent expansions, northwards to São Paulo State and southwards to Rio Grande do Sul State, are discussed, and a niche model of maximum entropy (MaxEnt) was performed to evaluate suitable C. limbata habitats. Brazilian populations are established and significantly increasing in most sites where the species has been detected. The distributional boundaries predicted by the model are clearly wider than their known range of occurrence, evidencing environmental suitability in both hemispheres from areas where the species still does not occur. Ecological processes such as competition, predation and specially habitat selectivity may regulate their populations and overall distribution range. A long-term monitoring programme and population genetics studies are necessary for a better understanding of this invasion and its consequences to natural communities.
- Sea turtle (Reptilia, Testudines) diversity and occurrence in the Azores Archipelago (NE Atlantic)Publication . Barcelos, Luis M. D.; Vandeperre, Frederic; Parra, Hugo; Barreiros, João P.BACKGROUND: Six species of marine turtles occur in the Azores Archipelago. The loggerhead, Caretta caretta (Linnaeus, 1758), is by far the most common species and is being constantly monitored and tagged by a joint project between the University of the Azores and the University of Florida since 1989. With the implementation of the tuna fishery observers (for dolphin safe seals), an increment of sea turtle reports has been verified as expected. The leather back turtle, Dermochelys coriacea (Vandelli, 1761) is the second most observed species in the Azores' EEZ, a fact probably also linked to the tuna fishery observation programme. All other species are occasional/vagrant albeit the green turtle, Chelonia mydas (Linnaeus, 1758) is more commonly seen than the others. Historically, sea turtles were occasionally taken for food in specific fishing villages and ports. Since 1986, sea turtles, as well as all marine mammals, are fully protected in the Azores although human-related activities (e.g. plastics, discarded fishing gear) do generate serious injuries and deaths. NEW INFORMATION: In this paper, we update sea turtle species' checklist for the Azores and give detailed geographic coordinates on their known occurrences.
- Meros do mundo, uma breve abordagemPublication . Barreiros, João P.OS MEROS DO MUNDO, peixes ósseos pertencentes à família Epinephelidae, contam presentemente cerca de cento e sessenta espécies que vão desde Epinephelus marginatus (Lowe, 1834), o tão emblemático mero do Mediterrâneo e da Macaronésia, conhecido - e muito apreciado - como Garoupa-verdadeira no Brasil, até espécies apenas descritas muito recentemente p. ex.: E. kupangensis Tucker, Kurniasih & Craig, 2016 e E. craigi Frable, Tucker & Walker, 2018 ou o “mero-misterioso”, E. lebretonianus (Hombron & Jacquinot, 1853), precisamente um caso de uma espécie da qual se conhece apenas um exemplar ou seja, o holótipo, aquele através do qual a espécie foi descrita. […].
- A ciência e os oceanosPublication . Barreiros, João P.Sendo um "lugar comum" falar-se dos Oceanos e dos mares do Mundo como a "última fronteira", nunca é demais voltar a realçar que muito temos ainda por descobrir, analisar e estudar nestes imentos ecossistemas que dominam o Planeta.