Mobility, Expansion and Management of a Multi-Species Scuba Diving Fishery in East Africa

Background: Scuba diving fishing, predominantly targeting sea cucumbers, has been documented to occur in an uncontrolled manner in the Western Indian Ocean and in other tropical regions. Although this type of fishing generally indicates a destructive activity, little attention has been directed towards this category of fishery, a major knowledge gap and barrier to management. Methodology and Principal Findings: With the aim to capture geographic scales, fishing processes and social aspects the scuba diving fishery that operate out of Zanzibar was studied using interviews, discussions, participant observations and catch monitoring. The diving fishery was resilient to resource declines and had expanded to new species, new depths and new fishing grounds, sometimes operating approximately 250 km away from Zanzibar at depths down to 50 meters, as a result of depleted easy-access stock. The diving operations were embedded in a regional and global trade network, and its actors operated in a roving manner on multiple spatial levels, taking advantage of unfair patron-client relationships and of the insufficient management in Zanzibar. Conclusions and Significance: This study illustrates that roving dynamics in fisheries, which have been predominantly addressed on a global scale, also take place at a considerably smaller spatial scale. Importantly, while proposed management of the sea cucumber fishery is often generic to a simplified fishery situation, this study illustrates

Effects of fishery protection on biometry and genetic structure of two target sea cucumber species from the Mediterranean Sea

Sea cucumber fisheries are now occurring in most of the tropical areas of the world, having expanded from its origin in the central Indo-Pacific. Due to the overexploitation of these resources and the increasing demand from Asian countries, new target species from Mediterranean Sea and northeastern Atlantic Ocean are being caught. The fishery effects on biometry and genetic structure of two target species (Holothuria polii and H. tubulosa) from Turkey, were assessed. The heaviest and largest individuals of H. polii were found into the non-fishery area of Kusadasi, also showing the highest genetic diversity. Similar pattern was detected in H. tubulosa, but only the weight was significantly higher in the protected area. However, the observed differences on the fishery effects between species, could be explained considering the different percentage of catches (80% for H. polii and 20% for H. tubulosa)

Fatal tiger shark, Galeocerdo cuvier attack in New Caledonia erroneously ascribed to great white shark, Carcharodon carcharias

To understand the causes and patterns of shark attacks on humans, accurate identification of the shark species involved is necessary. Often, the only reliable evidence for this comes from the characteristics of the wounds exhibited by the victim. The present case report is intended as a reappraisal of the Luengoni, 2007 case (International Shark Attack File no. 4299) where a single shark bite provoked the death of a swimmer by haemorrhagic shock. Our examination of the wounds on the body of the victim, here documented by so-far unpublished photographic evidence, determined that the shark possessed large and homodontous jaws. This demonstrates that the attacker was a tiger shark, not a great white shark as previously published

Latrodectism in New Caledonia : first report of presumed redback spider (Latrodectus hasselti) envenomation

We describe a recent case of presumed redback spider (Latrodectus hasselti) envenomation observed near Noumea in New Caledonia. This is the first local reported case in this archipelago, where L. hasselti is Currently considered a native species. We highlight the challenge of providing appropriate analgesia in this situation and believe that the use of specific redback spider antivenom should be considered in New Caledonia

Attaques de requins en Nouvelle-Calédonie de 1958 à 2020 : revue de cas

Background and objectives. Recent shark attacks in New Caledonia have prompted local authorities to elaborate a risk-management plan. The objective of the present paper is to produce detailed data on shark attacks that occurred in New Caledonian waters for the last few decades, as well as on the injuries of the victims, in order to inform rescue and medical services as well as authorities in charge of educating the public and providing security. Methods. Incidents involving sharks and humans in New Caledonia for the last six decades were included into a database. Sharks were tentatively identified to species according to the shape, size and other external characteristics of injuries to the victims, together with witness accounts. The severity of shark bites was evaluated against the scale proposed by A.K. Lentz and co-authors (Am Surg. 2010;76:101-6). Results. Sixty-seven shark-attack cases were recorded in New Caledonia from 1958 to 2020, of which 13 were lethal. The majority of the attacks concerned spearfishers and freedivers collecting invertebrates (58.5% of total). In the last decades, shark attacks may have increased towards bathers, swimmers and snorkelers (18.5%), and people taking part in water sports including surf, kitesurf, windsurf and SUP foil (14%). One scuba diver was also attacked (1.5%). Twenty attacks including 8 lethal ones were ascribed to the tiger shark Galeocerdo cuvier; 14 attacks including 2 lethal ones to the bull shark Carcharhinus leucas; 2 attacks including 1 lethal to the great white shark Carcharodon carcharias. The lethality of attacks was almost one in five, above the global average. Conclusions. Feeding incentive appeared to be a frequent factor triggering attacks. The education of the public should be promoted as a preventive measure aiming to reduce the risk of such accidents.Contexte et objectifs. Nous présentons une série de cas d’attaques de requins survenues en Nouvelle-Calédonie, destinée à proposer aux usagers du milieu marin concernés et aux autorités en charge de la sécurité du public un état des lieux de cette problématique Méthodes. Un recueil de cas réalisé par les auteurs a fait l’objet d’une base de données, dont les résultats sont analysés et présentés ici sous forme synthétique. Résultats. Nous avons répertorié 67 cas d’attaques de requins en Nouvelle-Calédonie de 1958 à 2020, dont 13 fatales. Le nombre des attaques a augmenté au fil des années. Les attaques ont concerné majoritairement des chasseurs sous-marins et des apnéistes récoltant des invertébrés (58,5 % du total des attaques). La proportion d’attaques de baigneurs, nageurs et adeptes du snorkeling (18,5 % du total des attaques) et celle des pratiquants des sports de glisse (14 %) pourrait avoir augmenté ces dernières décennies. Une attaque de plongeur en scaphandre autonome a été répertoriée. La létalité des attaques est de près d’une sur cinq, supérieure à la moyenne mondiale. Les principales espèces en cause sont le requin tigre Galeocerdo cuvier (20 attaques, dont huit mortelles) et le requin bouledogue Carcharhinus leucas (14 attaques, dont deux mortelles). Deux attaques ont été attribuées au grand requin blanc Carcharodon carcharias, dont une mortelle. Conclusions. La stimulation alimentaire apparaît comme le principal facteur favorisant les attaques. L’information du public mériterait d’être optimisée dans une perspective de prévention des accident

Attaques de requins en Nouvelle-Calédonie de 1958 à 2020 : revue de cas

International audienceBackground and objectives. Recent shark attacks in New Caledonia have prompted local authorities to elaborate a risk-management plan. The objective of the present paper is to produce detailed data on shark attacks that occurred in New Caledonian waters for the last few decades, as well as on the injuries of the victims, in order to inform rescue and medical services as well as authorities in charge of educating the public and providing security. Methods. Incidents involving sharks and humans in New Caledonia for the last six decades were included into a database. Sharks were tentatively identified to species according to the shape, size and other external characteristics of injuries to the victims, together with witness accounts. The severity of shark bites was evaluated against the scale proposed by A.K. Lentz and co-authors (Am Surg. 2010;76:101-6).Results. Sixty-seven shark-attack cases were recorded in New Caledonia from 1958 to 2020, of which 13 were lethal. The majority of the attacks concerned spearfishers and freedivers collecting invertebrates (58.5% of total). In the last decades, shark attacks may have increased towards bathers, swimmers and snorkelers (18.5%), and people taking part in water sports including surf, kitesurf, windsurf and SUP foil (14%). One scuba diver was also attacked (1.5%). Twenty attacks including 8 lethal ones were ascribed to the tiger shark Galeocerdo cuvier; 14 attacks including 2 lethal ones to the bull shark Carcharhinus leucas; 2 attacks including 1 lethal to the great white shark Carcharodon carcharias. The lethality of attacks was almost one in five, above the global average. Conclusions. Feeding incentive appeared to be a frequent factor triggering attacks. The education of the public should be promoted as a preventive measure aiming to reduce the risk of such accidents.Contexte et objectifs. Nous présentons une série de cas d’attaques de requins survenues en Nouvelle-Calédonie, destinée à proposer aux usagers du milieu marin concernés et aux autorités en charge de la sécurité du public un état des lieux de cette problématiqueMéthodes. Un recueil de cas réalisé par les auteurs a fait l’objet d’une base de données, dont les résultats sont analysés et présentés ici sous forme synthétique.Résultats. Nous avons répertorié 67 cas d’attaques de requins en Nouvelle-Calédonie de 1958 à 2020, dont 13 fatales. Le nombre des attaques a augmenté au fil des années. Les attaques ont concerné majoritairement des chasseurs sous-marins et des apnéistes récoltant des invertébrés (58,5 % du total des attaques). La proportion d’attaques de baigneurs, nageurs et adeptes du snorkeling (18,5 % du total des attaques) et celle des pratiquants des sports de glisse (14 %) pourrait avoir augmenté ces dernières décennies. Une attaque de plongeur en scaphandre autonome a été répertoriée. La létalité des attaques est de près d’une sur cinq, supérieure à la moyenne mondiale. Les principales espèces en cause sont le requin tigre Galeocerdo cuvier (20 attaques, dont huit mortelles) et le requin bouledogue Carcharhinus leucas (14 attaques, dont deux mortelles). Deux attaques ont été attribuées au grand requin blanc Carcharodon carcharias, dont une mortelle. Conclusions. La stimulation alimentaire apparaît comme le principal facteur favorisant les attaques. L’information du public mériterait d’être optimisée dans une perspective de prévention des accidents

Conductivity of transparent electrodes made from interacting nanotubes

Interactions in carbon nanotube (CNT) dispersions alter the morphology of films made from such dispersions. Weak attractive interactions induce an enhancement of the electrical conductivity. This phenomenon is observed in thin films that lie in a near percolated regime. Strong interactions instead induce a decrease of conductivity. In spite of strong morphological differences, the conductivity of thick films, away from percolated regimes, do not depend on interactions between the CNTs. These experiments support a recent theoretical scenario of the percolation of interacting rods and provide guidance for the optimal formulations of CNT inks in transparent electrode applications

Double lethal coconut crab (Birgus latro L.) poisoning

We report a double lethal coconut crab Birgus latro L poisoning in New Caledonia. Both patients died after showing gastro-intestinal symptoms, major bradycardia with marked low blood pressure, and finally asystolia. Both had significative hyperkaliemia, suggesting a digitaline-like substance intoxication. Traditional knowledge in the Loyalty Islands relates coconut crab toxicity to the consumption of the Cerbera manghas fruit by the crustacean. Elsewhere previous descriptions of human poisoning with the kernel of fruits of trees belonging to the genus Cerbera, known to contain cardiotoxic cardenolides, appear to be very similar to our cases. Cardenolides assays were performed on patient's serum samples, fruit kernel and on the crustacean guts, which lead us to suppose these two fatal cases were the result of a neriifolin intoxication, this toxin having been transmitted through the coconut crab