The aim of this study, carried out during 2001 and 2002, was to assess the interaction between tu... more The aim of this study, carried out during 2001 and 2002, was to assess the interaction between turtles and bottom trawls in the Gulf of Gabes, which is considered an important wintering and foraging area for the loggerhead in the Mediterranean. Catch rates are estimated at 0.01142±0.00292 turtles/haul with a total catch of 5458±1652 turtles/year. However, the total mortality is low (182±55/year), probably due to the short haul duration. Captures occur mainly during winter, spring and summer, with significantly higher rates at depths of less than 50 m.
ABSTRACT A survey of cetaceans stranded along the Tunisian coastline (2004 – 2009) and a review o... more ABSTRACT A survey of cetaceans stranded along the Tunisian coastline (2004 – 2009) and a review of the literature allowed us to record a total number of 132 stranding events from 1937 to 2009. They included two species of balaenopteridae, one species of physeteridae and fi ve species of delphinidae. The common bottlenose dolphin Tursiops truncatus (Montagu, 1821) and the fi n whale Balaenoptera physalus (Linnaeus, 1758) were the main stranded species in 83 and 21 stranding cases, respectively, representing 78.78 % of all records. Stranding events occurred all the year round, with the highest frequency in spring (21.68 % ) and summer (50.60 % ) for the common bottlenose dolphin and in winter for the fi n whale (50 % ). The common bottlenose dolphin was more vulnerable to human and fi sheries interaction while the fi n whale was more prone to be trapped in shallow waters. Keywords: Balaenoptera physalus; stranding; Tunisian coastline; Tursiops truncatus.
Abstract This is the first record of the red alga Polysiphonia carettia Hollenberg (Rhodomeleacea... more Abstract This is the first record of the red alga Polysiphonia carettia Hollenberg (Rhodomeleaceae) in the Gulf of Gabes, Tunisia (Mediterranean Sea). This species was first described growing on the carapace of the loggerhead sea turtle Caretta caretta (L.) from Santa Catalina Island, California, USA. In the Mediterranean, it was reported only from two loggerhead turtles captured by a Spanish longline vessel. The morphology, habitat and geographical distribution of P. carettia were examined.
The main objective of the study was to assess the abundance and distribution of sharks in Ghana’s... more The main objective of the study was to assess the abundance and distribution of sharks in Ghana’s coastal area. Samples were collected daily from the three sampling sites from April – to December 2021. The data obtained from this study were assessed for species abundance and composition, ecological indices; species diversity, and exploitation status using PAST and Microsoft Excel. A total of eight species were recorded with Prionace glauca (68%) as the dominant species and Carcharhinus leucas (1%) as the least dominant species. The mean species richness index (SRI) of 0.9 indicated infinite diversity of the species. The mean species evenness index (SEI) of 0.5 showed an evenly distributed species. The mean species dominance index (SDI) of 0.4 implied that the habitat was not dominated by only one or two particular species. The mean Shannon Weiner index (SWI) was less than 3, which is suggestive of pollution and habitat degradation. The exploitation status indicated that the stock of...
Boletín de la Asociación Herpetológica Española, 2011
El objetivo del presente trabajo es dar a conocer lo que parece el primer caso documentado de exp... more El objetivo del presente trabajo es dar a conocer lo que parece el primer caso documentado de expulsion de un anzuelo de palangre en una tortuga boba en libertad. El ejemplar era un subadulto con una longitud curva minima del caparazon de 58 cm. Tras ser capturado en el sureste de Menorca (Islas Baleares) el 11 de junio de 2006, se libero con un anzuelo. Este no se hallo durante la necropsia realizada en Tunez, tras su varamiento como cadaver 691 dias despues de su liberacion. Aunque en estudios previos se han descrito casos similares de ejemplares recuperados en cautividad, se desconoce la frecuencia de hechos similares, asi como las caracteristicas de dichos ejemplares (tamano, sexo, estado fisico).
The authors have compiled published information on taxonomy, distribution, status, statistics, fi... more The authors have compiled published information on taxonomy, distribution, status, statistics, fisheries, bycatch, biologic, and ecologic parameters mainly on food and feeding habits and reproductive biology of elasmobranchs along the Tunisian coasts. This bibliographic analysis shows that cartilaginous species, including sharks and rays are by far the most endangered group of marine fish, with 63 species, about 53% of all are critically endangered, endangered, or vulnerable. Overfishing, fishing practices, and habitat degradation are leading to dramatic declines of these species. Biologic parameters concern a few species primarily in the Gulf of Gabes. Therefore, recommendations to fill gaps in order to protect and manage elasmobranchs stocks are proposed in this chapter.
The aim of this study, carried out during 2001 and 2002, was to assess the interaction between tu... more The aim of this study, carried out during 2001 and 2002, was to assess the interaction between turtles and bottom trawls in the Gulf of Gabes, which is considered an important wintering and foraging area for the loggerhead in the Mediterranean. Catch rates are estimated at 0.01142±0.00292 turtles/haul with a total catch of 5458±1652 turtles/year. However, the total mortality is low (182±55/year), probably due to the short haul duration. Captures occur mainly during winter, spring and summer, with significantly higher rates at depths of less than 50 m.
ABSTRACT A survey of cetaceans stranded along the Tunisian coastline (2004 – 2009) and a review o... more ABSTRACT A survey of cetaceans stranded along the Tunisian coastline (2004 – 2009) and a review of the literature allowed us to record a total number of 132 stranding events from 1937 to 2009. They included two species of balaenopteridae, one species of physeteridae and fi ve species of delphinidae. The common bottlenose dolphin Tursiops truncatus (Montagu, 1821) and the fi n whale Balaenoptera physalus (Linnaeus, 1758) were the main stranded species in 83 and 21 stranding cases, respectively, representing 78.78 % of all records. Stranding events occurred all the year round, with the highest frequency in spring (21.68 % ) and summer (50.60 % ) for the common bottlenose dolphin and in winter for the fi n whale (50 % ). The common bottlenose dolphin was more vulnerable to human and fi sheries interaction while the fi n whale was more prone to be trapped in shallow waters. Keywords: Balaenoptera physalus; stranding; Tunisian coastline; Tursiops truncatus.
Abstract This is the first record of the red alga Polysiphonia carettia Hollenberg (Rhodomeleacea... more Abstract This is the first record of the red alga Polysiphonia carettia Hollenberg (Rhodomeleaceae) in the Gulf of Gabes, Tunisia (Mediterranean Sea). This species was first described growing on the carapace of the loggerhead sea turtle Caretta caretta (L.) from Santa Catalina Island, California, USA. In the Mediterranean, it was reported only from two loggerhead turtles captured by a Spanish longline vessel. The morphology, habitat and geographical distribution of P. carettia were examined.
The main objective of the study was to assess the abundance and distribution of sharks in Ghana’s... more The main objective of the study was to assess the abundance and distribution of sharks in Ghana’s coastal area. Samples were collected daily from the three sampling sites from April – to December 2021. The data obtained from this study were assessed for species abundance and composition, ecological indices; species diversity, and exploitation status using PAST and Microsoft Excel. A total of eight species were recorded with Prionace glauca (68%) as the dominant species and Carcharhinus leucas (1%) as the least dominant species. The mean species richness index (SRI) of 0.9 indicated infinite diversity of the species. The mean species evenness index (SEI) of 0.5 showed an evenly distributed species. The mean species dominance index (SDI) of 0.4 implied that the habitat was not dominated by only one or two particular species. The mean Shannon Weiner index (SWI) was less than 3, which is suggestive of pollution and habitat degradation. The exploitation status indicated that the stock of...
Boletín de la Asociación Herpetológica Española, 2011
El objetivo del presente trabajo es dar a conocer lo que parece el primer caso documentado de exp... more El objetivo del presente trabajo es dar a conocer lo que parece el primer caso documentado de expulsion de un anzuelo de palangre en una tortuga boba en libertad. El ejemplar era un subadulto con una longitud curva minima del caparazon de 58 cm. Tras ser capturado en el sureste de Menorca (Islas Baleares) el 11 de junio de 2006, se libero con un anzuelo. Este no se hallo durante la necropsia realizada en Tunez, tras su varamiento como cadaver 691 dias despues de su liberacion. Aunque en estudios previos se han descrito casos similares de ejemplares recuperados en cautividad, se desconoce la frecuencia de hechos similares, asi como las caracteristicas de dichos ejemplares (tamano, sexo, estado fisico).
The authors have compiled published information on taxonomy, distribution, status, statistics, fi... more The authors have compiled published information on taxonomy, distribution, status, statistics, fisheries, bycatch, biologic, and ecologic parameters mainly on food and feeding habits and reproductive biology of elasmobranchs along the Tunisian coasts. This bibliographic analysis shows that cartilaginous species, including sharks and rays are by far the most endangered group of marine fish, with 63 species, about 53% of all are critically endangered, endangered, or vulnerable. Overfishing, fishing practices, and habitat degradation are leading to dramatic declines of these species. Biologic parameters concern a few species primarily in the Gulf of Gabes. Therefore, recommendations to fill gaps in order to protect and manage elasmobranchs stocks are proposed in this chapter.
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