Gingival lymphatic malformation. An atypical case report

Lymphatic malformations are a rare pathology that presents a highly variable clinical expression. Intraorally, it mainly affects the dorsum of the tongue. The objective of this work is to present a case of lymphatic malformation in an atypical location. A 20-year-old male who attended the clinic for multiple vesicular lesion in attached gingiva, asymptomatic and of unknown evolution. Removal of the lesion and subsequent histological analysis were performed, which showed a microcystic lymphatic vascular lesion. Immunohistochemistry for D2-40 was performed, which corroborated the lymphatic origin of the lesion. At 6 months, no recurrence of the lesion was recognized. Clinicians should include lymphatic malformations in the differential diagnosis of multiple vesicular lesions. Knowing the oral manifestations of this entity is essential for its proper diagnosis and clinical management

A Preliminary Habitat Suitability Model for Devil Rays in the Western Indian Ocean

The European tropical tuna purse seine fishery incidentally captures three highly migratory and endangered species of devil rays, spinetail devil ray Mobula mobular, sicklefin devil ray M. tarapacana, and bentfin devil ray M. thurstoni in the Indian Ocean. Due to their global decreasing populations, understanding the factors of their spatial and temporal distributions and the associated environmental conditions are fundamental for their management and conservation. Yet, the spatial and temporal distribution of devil rays in the Indian Ocean is poorly understood. Here we developed a habitat suitability model for devil rays in the Western Indian Ocean depicting the seasonal and interannual changes in their spatial distributions and underlying environmental conditions. We used bycatch data collected between the period 2010-2020 by the EU tropical tuna purse seine observer programs to determine which environmental variables influence the occurrence of devil rays using generalized additive models. A separate modelling was done for the spinetail devil ray, and for the three species of devil rays combined, since many individuals are only recorded at the genus level. The environmental variables associated with the presence of devil rays were chlorophyll, sea surface height and sea surface temperature fronts. When modelling the habitat suitability for spinetail devil ray, the most influential environmental variables were net primary production of phytoplankton and sea surface temperature fronts. Both the interannual and seasonal variability in habitat suitability of devil rays were explained by these environmental variables. We also showed that devil rays are associated to permanent hotspots in the Mascarene Plateau and Central Indian Ridge, and to seasonal hotspots in the Western Arabian Sea and Equatorial regions where there is a high occurrence of devil rays during winter monsoon. We found that setting on large tuna schools decreases the chances of devil ray bycatch. Both models predicted a higher probability of incidental catch of devil rays in fishing sets on free swimming schools of tunas than in sets on fish aggregating devices. The identified hotspots and associated environmental characteristics provide information about the habitat use and ecology of the devil rays in the Western Indian Ocean. Furthermore, the habitat suitability models, and biological hotspots identified in this study could also to be used to inform the development of future spatial management measures, including time-area closures, to minimize the interaction of pelagic fisheries with these vulnerable species

A preliminary habitat suitability model for oceanic whitetip shark in the western Indian Ocean

Understanding the temporal, spatial and environmental factors influencing species distributions is essential to minimize the interactions of vulnerable species with fisheries and can be used to identify areas of high bycatch rates and their environmental conditions. Classified as critically endangered by the International Union for the Conservation of Nature, the oceanic whitetip shark (Carcharhinus longimanus) is the second main shark species incidentally caught by the tropical tuna purse seine fishery in the western Indian Ocean. In this study, we used the European Union purse seine fishery observer data (2010-2020) and generalized additive models to develop a habitat suitability model for juvenile oceanic whitetip shark in the western Indian Ocean. Sea surface temperature was the main environmental driver suggesting a higher probability of occurrence of this shark with decreasing temperatures. The type of fishing operation also was an important predictor explaining its occurrence, suggesting a higher probability of incidentally catching this species when using fish aggregating devices as set type. Moreover, predictive maps of habitat suitability suggested the area offshore of Kenya and Somalia are an important hotspot with higher probabilities of incidentally catching this species during the summer monsoon (June to September) when upwelling takes place. The habitat suitability models developed here could be used to inform the design and testing of potential time-area closures in the Kenya-Somalia basin with the objective of minimizing the bycatch of this critically endangered species with the least possible impact on fishing operations and fishery yields of target tuna

Bycatch species composition over time by tuna purse-seine fishery in the eastern tropical Atlantic Ocean.

Post-print

Biodiversity and Habitat Characteristics of the Bycatch Assemblages in Fish Aggregating Devices (FADs) and School Sets in the Eastern Pacific Ocean

This study examined diversity and habitat characteristics for bycatch assemblages in two different types of fishing (drifting fish aggregating devices sets and sets made on school of tunas) in the eastern Pacific Ocean (20°S–30°N and 70°–150°W) between 2005 and 2011 using biodiversity metrics and Generalized Additive Models. Bycatch information was based on data collected by onboard observers covering more than 80% of the purse seine fishing trips. Our results suggest that diversity and habitat characteristics of the bycatch assemblages differ depending of the fishing mode. Thus, diversity was mostly explained by area and set type; being higher in fish aggregating devices (FAD) sets than School sets. Concretely, diversity seems to be directly related with the equatorial upwelling and the front system in FAD sets and with the Costa Rica Dome and the coastal upwelling of Panama induced by wind jets in School sets. Among environmental variables, temperature and chlorophyll were the most important predictors to describe the diversity of the bycatch assemblages. This work has investigated multiple indicators related to the bycatch assemblages and their habitat, which could be helpful for the development of an Ecosystem Approach to Fishery Management (EAFM)

Present and Future Potential Habitat Distribution of Carcharhinus falciformis and Canthidermis maculata By-Catch Species in the Tropical Tuna Purse-Seine Fishery under Climate Change

By-catch species from tropical tuna purse seine fishery have been affected by fishery pressures since the last century; however, the habitat distribution and the climate change impacts on these species are poorly known. With the objective of predicting the potential suitable habitat for a shark (Carcharhinus falciformis) and a teleost (Canthidermis maculata) in the Indian, Atlantic and Eastern Pacific Oceans, a MaxEnt species distribution model (SDM) was developed using data collected by observers in tuna purse seiners. The relative percentage of contribution of some environmental variables (depth, sea surface temperature, salinity and primary production) and the potential impact of climate change on species habitat by the end of the century under the A2 scenario (scenario with average concentrations of carbon dioxide of 856 ppm by 2100) were also evaluated. Results showed that by-catch species can be correctly modeled using observed occurrence records and few environmental variables with SDM. Results from projected maps showed that the equatorial band and some coastal upwelling regions were the most suitable areas for both by-catch species in the three oceans in concordance with the main fishing grounds. Sea surface temperature was the most important environmental variable which contributed to explain the habitat distribution of the two species in the three oceans in general. Under climate change scenarios, the largest change in present habitat suitability is observed in the Atlantic Ocean (around 16% of the present habitat suitability area of C. falciformis and C. maculata, respectively) whereas the change is less in the Pacific (around 10 and 8%) and Indian Oceans (around 3 and 2%). In some regions such as Somalia, the Atlantic equatorial band or Peru's coastal upwelling areas, these species could lose potential habitat whereas in the south of the equator in the Indian Ocean, the Benguela System and in the Pacific coast of Central America, they could gain suitable habitat as consequence of global warming. This work presents new information about the present and future habitat distribution under climate change of both by-catch species which can contributes to the development of ecosystem-based fishery management and spatially driven management measures

Spatio-Temporal Distribution of Juvenile Oceanic Whitetip Shark Incidental Catch in the Western Indian Ocean

Oceanic whitetip shark (Carcharhinus longimanus) is an important top predator in pelagic ecosystems currently classified as globally Critically Endangered by the International Union for the Conservation of Nature. This species is incidentally caught by fisheries targeting highly migratory tunas and billfishes throughout the Indian Ocean. Understanding the temporal, spatial and environmental factors influencing the capture of this species is essential to reduce incidental catches. In this study, we used generalized additive models to analyze the spatio-temporal distributions of the juvenile oceanic whitetip shark catches and the environmental conditions in the western Indian Ocean using observer data from 2010 to 2020 of the European Union and associated flags purse seine fishery. We found sea surface temperature and nitrate concentration to be the most important environmental variables predicting the probability of catching an oceanic whitetip shark. A higher probability of capture was predicted in areas where sea surface temperature was below 24°C and with low nitrate concentrations close to zero and intermediate values (1.5-2.5 mmol.m-3). We also found a higher probability of capture in sets on fish aggregating devices than in sets on free schools of tuna. The Kenya and Somalia basin was identified to have higher probabilities of capture during the summer monsoon (June to September) when upwelling of deep cold waters occurs. We provide the first prediction maps of capture probabilities and insights into the environmental preferences of oceanic whitetip shark in the western Indian Ocean. However, the causal mechanisms behind these insights should be explored in future studies before they can be used to design spatial management and conservation strategies, such as time-area closures, for bycatch avoidance

Spatio-Temporal Distribution of Juvenile Oceanic Whitetip Shark Incidental Catch in the Western Indian Ocean

Oceanic whitetip shark (Carcharhinus longimanus) is an important top predator in pelagic ecosystems currently classified as globally Critically Endangered by the International Union for the Conservation of Nature. This species is incidentally caught by fisheries targeting highly migratory tunas and billfishes throughout the Indian Ocean. Understanding the temporal, spatial and environmental factors influencing the capture of this species is essential to reduce incidental catches. In this study, we used generalized additive models to analyze the spatio-temporal distributions of the juvenile oceanic whitetip shark catches and the environmental conditions in the western Indian Ocean using observer data from 2010 to 2020 of the European Union and associated flags purse seine fishery. We found sea surface temperature and nitrate concentration to be the most important environmental variables predicting the probability of catching an oceanic whitetip shark. A higher probability of capture was predicted in areas where sea surface temperature was below 24°C and with low nitrate concentrations close to zero and intermediate values (1.5-2.5 mmol.m-3). We also found a higher probability of capture in sets on fish aggregating devices than in sets on free schools of tuna. The Kenya and Somalia basin was identified to have higher probabilities of capture during the summer monsoon (June to September) when upwelling of deep cold waters occurs. We provide the first prediction maps of capture probabilities and insights into the environmental preferences of oceanic whitetip shark in the western Indian Ocean. However, the causal mechanisms behind these insights should be explored in future studies before they can be used to design spatial management and conservation strategies, such as time-area closures, for bycatch avoidance