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Underwater noise pollution is an increasing threat to marine ecosystems. Marine animals use sound in communication and orientation processes. The introduction of anthropogenic noise in their habitat can interfere with sound production and reception as well as with the acquisition of vital information through other sensory systems. In the blue crab (Callinectes sapidus), the statocyst is responsible for acoustic perception, and it is housed at the base of its first pair of antennae (antennule). The sensilla of the distal part of these antennule hosts the olfactory system, which is key for foraging. Given the anatomical proximity of the two sensory regions, we evaluated the possible interference of sound exposure with the crab ability to find food, by using an aquatic maze, and looked at the potential impairment of the righting reflex as well as at ultrastructural damages in statocysts. Although a significant effect was observed when looking at the time used by the animal to recover its habitual position (“righting reflex”), which was associated to lesions in the statocyst sensory epithelia, the time required to find food did not increase after the exposure to sound. When the crabs were exposed to natural sounds (marine background noise and sounds of their predators: Micropogonias undulates and Sciaenops ocellatus) they did not show significant differences in foraging behaviour. Although we found no unequivocal evidence of a negative impact of sound on olfactory capabilities, the study showed a clear righting reflex impairment correlated with ultrastructural damages of the statocysts. We argue that crab populations that cannot easily avoid noise sources due to their specific coastal distributions may incur in significant direct fitness costs (e.g. impairment of complex reflexes). This integrated approach to sound effect assessment could be used as a model for other invertebrate species to effectively monitor noise impact in marine environments., Peer Reviewed, Postprint (published version)

The aim of this work was to extract a bioactive material « chitosan » from the by-products of blue crab (P. segnis) by chemical extraction method. The physico-chemical, functional and biological properties of the chitosan obtained were evaluated. The yield of the extracted chitosan was calculated as 9.2 ± 2.03%. The proximate analysis showed 2 ± 0.03% moisture, 0.57 ± 0.02% ash, 0.3 ± 0.01% lipid and 0,2 ± 0,03% protein contents in chitosan. Degree of deacetylation (DD) value was calculated using potentiometric titration (78.97 ± 0.38%) and FTIR (81,47 ± 0.51%) resulting in a high DD. Whiteness value, water and fat binding capacities of the chitosan were high and are suitable for many functional food applications. Structural characterization was performed using FTIR spectroscopy which confirms the presence of amino group of chitosan synthesized. Antioxidant activity assay showed that chitosan exhibited notable antioxidant activity against DPPH (20.13 ± 1.41% to 70.63 ± 1.26%), but lower than that of ascorbic acid (49.17 ± 1.13% to 87.46 ± 1.22%) at the same concentrations (0,5 to 10 mg/mL), in a dose dependent manner. Its required IC50 to inhibit 50% of radical DPPH was 1.86 ± 0.31 mg/mL. Extracted chitosan showed a significant antimicrobial activity against bacteria and fungi. In conclusion, the extracted chitosan is an effective natural biopolymer possessing potential properties.

The aim of this work was to extract a bioactive material « chitosan » from the by-products of blue crab (P. segnis) by chemical extraction method. The physico-chemical, functional and biological properties of the chitosan obtained were evaluated. The yield of the extracted chitosan was calculated as 9.2 ± 2.03%. The proximate analysis showed 2 ± 0.03% moisture, 0.57 ± 0.02% ash, 0.3 ± 0.01% lipid and 0,2 ± 0,03% protein contents in chitosan. Degree of deacetylation (DD) value was calculated using potentiometric titration (78.97 ± 0.38%) and FTIR (81,47 ± 0.51%) resulting in a high DD. Whiteness value, water and fat binding capacities of the chitosan were high and are suitable for many functional food applications. Structural characterization was performed using FTIR spectroscopy which confirms the presence of amino group of chitosan synthesized. Antioxidant activity assay showed that chitosan exhibited notable antioxidant activity against DPPH (20.13 ± 1.41% to 70.63 ± 1.26%), but lower than that of ascorbic acid (49.17 ± 1.13% to 87.46 ± 1.22%) at the same concentrations (0,5 to 10 mg/mL), in a dose dependent manner. Its required IC50 to inhibit 50% of radical DPPH was 1.86 ± 0.31 mg/mL. Extracted chitosan showed a significant antimicrobial activity against bacteria and fungi. In conclusion, the extracted chitosan is an effective natural biopolymer possessing potential properties.

The aim of this work was to extract a bioactive material « chitosan » from the by-products of blue crab (P. segnis) by chemical extraction method. The physico-chemical, functional and biological properties of the chitosan obtained were evaluated. The yield of the extracted chitosan was calculated as 9.2 ± 2.03%. The proximate analysis showed 2 ± 0.03% moisture, 0.57 ± 0.02% ash, 0.3 ± 0.01% lipid and 0,2 ± 0,03% protein contents in chitosan. Degree of deacetylation (DD) value was calculated using potentiometric titration (78.97 ± 0.38%) and FTIR (81,47 ± 0.51%) resulting in a high DD. Whiteness value, water and fat binding capacities of the chitosan were high and are suitable for many functional food applications. Structural characterization was performed using FTIR spectroscopy which confirms the presence of amino group of chitosan synthesized. Antioxidant activity assay showed that chitosan exhibited notable antioxidant activity against DPPH (20.13 ± 1.41% to 70.63 ± 1.26%), but lower than that of ascorbic acid (49.17 ± 1.13% to 87.46 ± 1.22%) at the same concentrations (0,5 to 10 mg/mL), in a dose dependent manner. Its required IC50 to inhibit 50% of radical DPPH was 1.86 ± 0.31 mg/mL. Extracted chitosan showed a significant antimicrobial activity against bacteria and fungi. In conclusion, the extracted chitosan is an effective natural biopolymer possessing potential properties.

Increases in the sizes of container ships due to the expansion of the Panama Canal has increased the need for dredging activities in the Chesapeake Bay. Placement of dredged material in the Bay is restricted to winter months owing to concerns for threatened and endangered species. Placement of dredged material in the lower Chesapeake Bay in Wolf Trap Alternate Open Water Placement Site (WTAPS) overlaps with overwintering locations for mature female blue crab. To estimate the potential magnitude of winter mortality in WTAPS and WTAPS Northern Extension (WTAPSNE) resulting from placement of dredged material, a range of geostatistical tools (e.g., inverse distance weighting and kriging) were used to map the distribution and estimate the abundance of blue crab in Chesapeake Bay, WTAPS, and WTAPSNE (i.e., small-scale estimation) from 1990–2020 using data from the winter dredge survey. These analyses indicated that a low proportion of the age-1+ female blue crab population occurs within WTAPS and WTAPSNE (<1.18% and <1.5% respectively). Variability of abundance estimates was high when female age-1+ abundance was less than 150 million in the Chesapeake Bay. Therefore, we suggest the Port limit placement of dredged materials in WTAPS and WTAPSNE when female age-1+ abundance is less than 150 million; we recommend the Port not undertake placement activities when the stock is declared overfished (i.e., when female age-1+ abundance is less than 72.5 million).

The aim of this work was to extract a bioactive material « chitosan » from the by-products of blue crab (P. segnis) by chemical extraction method. The physico-chemical, functional and biological properties of the chitosan obtained were evaluated. The yield of the extracted chitosan was calculated as 9.2 ± 2.03%. The proximate analysis showed 2 ± 0.03% moisture, 0.57 ± 0.02% ash, 0.3 ± 0.01% lipid and 0,2 ± 0,03% protein contents in chitosan. Degree of deacetylation (DD) value was calculated using potentiometric titration (78.97 ± 0.38%) and FTIR (81,47 ± 0.51%) resulting in a high DD. Whiteness value, water and fat binding capacities of the chitosan were high and are suitable for many functional food applications. Structural characterization was performed using FTIR spectroscopy which confirms the presence of amino group of chitosan synthesized. Antioxidant activity assay showed that chitosan exhibited notable antioxidant activity against DPPH (20.13 ± 1.41% to 70.63 ± 1.26%), but lower than that of ascorbic acid (49.17 ± 1.13% to 87.46 ± 1.22%) at the same concentrations (0,5 to 10 mg/mL), in a dose dependent manner. Its required IC50 to inhibit 50% of radical DPPH was 1.86 ± 0.31 mg/mL. Extracted chitosan showed a significant antimicrobial activity against bacteria and fungi. In conclusion, the extracted chitosan is an effective natural biopolymer possessing potential properties.

The aim of this work was to extract a bioactive material « chitosan » from the by-products of blue crab (P. segnis) by chemical extraction method. The physico-chemical, functional and biological properties of the chitosan obtained were evaluated. The yield of the extracted chitosan was calculated as 9.2 ± 2.03%. The proximate analysis showed 2 ± 0.03% moisture, 0.57 ± 0.02% ash, 0.3 ± 0.01% lipid and 0,2 ± 0,03% protein contents in chitosan. Degree of deacetylation (DD) value was calculated using potentiometric titration (78.97 ± 0.38%) and FTIR (81,47 ± 0.51%) resulting in a high DD. Whiteness value, water and fat binding capacities of the chitosan were high and are suitable for many functional food applications. Structural characterization was performed using FTIR spectroscopy which confirms the presence of amino group of chitosan synthesized. Antioxidant activity assay showed that chitosan exhibited notable antioxidant activity against DPPH (20.13 ± 1.41% to 70.63 ± 1.26%), but lower than that of ascorbic acid (49.17 ± 1.13% to 87.46 ± 1.22%) at the same concentrations (0,5 to 10 mg/mL), in a dose dependent manner. Its required IC50 to inhibit 50% of radical DPPH was 1.86 ± 0.31 mg/mL. Extracted chitosan showed a significant antimicrobial activity against bacteria and fungi. In conclusion, the extracted chitosan is an effective natural biopolymer possessing potential properties.

Callinectes sapidus Rathbun (1896) es un crustáceo invasor con origen en la costa este del continente americano, ha extendido su presencia en la costa del Mediterráneo con poblaciones establecidas sobre todo a lo largo de la costa valenciana y en el delta del Ebro. En el presente trabajo se analiza la capturabilidad o eficiencia de captura en este caso, así como la capacidad de retención de las nasas que se están usando para su captura. El estudio se llevó a cabo en el Barranco de San Nicolás, Gandía, zona conectada con el mar por el puerto de Gandía y con aporte de agua dulce de las acequias del marjal. El análisis de la capturabilidad se determinó mediante técnicas de vídeo, las grabaciones se realizaron durante distintos horarios de supuesta mayor y menor actividad según otros autores y distintos rangos de temperatura y se compararon también los resultados con la actividad según estos., Callinectes sapidus Rathbun (1896) és un crustaci invasor amb origen en la costa est del continent americà, ha estés la seua presència en la costa del Mediterrani amb poblacions establides sobretot al llarg de la costa valenciana i en el delta de l'Ebre. En el present treball s'analitza la capturabilitat o eficiència de captura en aquest cas, així com la capacitat de retenció de les nases que s'estan utilitzant per a la seua captura. L'estudi es va dur a terme en el Barranc de Sant Nicolás, Gandia, zona connectada amb la mar pel port de Gandia i amb aportació d'aigua dolça de les séquies de la marjal. L'anàlisi de la capturabilitat es va determinar mitjançant tècniques de vídeo, els enregistraments de vídeo es van realitzar durant diferents horaris de suposada major i menor activitat segons altres autors i diferents rangs de temperatura i també es van comparar els resultats amb l'activitat segons aquests., Callinectes sapidus (Rathbun 1896) is an invasive crustacean with origin on the east coast of the American continent, it has spread its presence over the Mediterranean coast with established populations especially along the valencian coast and in the Ebro’s delta. This work analyzes the catchability or efficiency of capture in this case, as well as the retention capacity of the traps that are being used for its capture. The study was carried out in the Barranco de San Nicolás, Gandía, an area connected to the sea by the port of Gandía and provided with fresh water from the ditches of the marsh. The catchability analysis was determined using video techniques, the recordings were made during different schedules of supposed higher and lower activity according to other authors and different temperature ranges, and the results were also compared with what was expected according to these autors

Callinectes sapidus Rathbun (1896) es un crustáceo invasor con origen en la costa este del continente americano, ha extendido su presencia en la costa del Mediterráneo con poblaciones establecidas sobre todo a lo largo de la costa valenciana y en el delta del Ebro. En el presente trabajo se analiza la capturabilidad o eficiencia de captura en este caso, así como la capacidad de retención de las nasas que se están usando para su captura. El estudio se llevó a cabo en el Barranco de San Nicolás, Gandía, zona conectada con el mar por el puerto de Gandía y con aporte de agua dulce de las acequias del marjal. El análisis de la capturabilidad se determinó mediante técnicas de vídeo, las grabaciones se realizaron durante distintos horarios de supuesta mayor y menor actividad según otros autores y distintos rangos de temperatura y se compararon también los resultados con la actividad según estos., Callinectes sapidus Rathbun (1896) és un crustaci invasor amb origen en la costa est del continent americà, ha estés la seua presència en la costa del Mediterrani amb poblacions establides sobretot al llarg de la costa valenciana i en el delta de l'Ebre. En el present treball s'analitza la capturabilitat o eficiència de captura en aquest cas, així com la capacitat de retenció de les nases que s'estan utilitzant per a la seua captura. L'estudi es va dur a terme en el Barranc de Sant Nicolás, Gandia, zona connectada amb la mar pel port de Gandia i amb aportació d'aigua dolça de les séquies de la marjal. L'anàlisi de la capturabilitat es va determinar mitjançant tècniques de vídeo, els enregistraments de vídeo es van realitzar durant diferents horaris de suposada major i menor activitat segons altres autors i diferents rangs de temperatura i també es van comparar els resultats amb l'activitat segons aquests., Callinectes sapidus (Rathbun 1896) is an invasive crustacean with origin on the east coast of the American continent, it has spread its presence over the Mediterranean coast with established populations especially along the valencian coast and in the Ebro’s delta. This work analyzes the catchability or efficiency of capture in this case, as well as the retention capacity of the traps that are being used for its capture. The study was carried out in the Barranco de San Nicolás, Gandía, an area connected to the sea by the port of Gandía and provided with fresh water from the ditches of the marsh. The catchability analysis was determined using video techniques, the recordings were made during different schedules of supposed higher and lower activity according to other authors and different temperature ranges, and the results were also compared with what was expected according to these autors

Callinectes sapidus Rathbun (1896) es un crustáceo invasor con origen en la costa este del continente americano, ha extendido su presencia en la costa del Mediterráneo con poblaciones establecidas sobre todo a lo largo de la costa valenciana y en el delta del Ebro. En el presente trabajo se analiza la capturabilidad o eficiencia de captura en este caso, así como la capacidad de retención de las nasas que se están usando para su captura. El estudio se llevó a cabo en el Barranco de San Nicolás, Gandía, zona conectada con el mar por el puerto de Gandía y con aporte de agua dulce de las acequias del marjal. El análisis de la capturabilidad se determinó mediante técnicas de vídeo, las grabaciones se realizaron durante distintos horarios de supuesta mayor y menor actividad según otros autores y distintos rangos de temperatura y se compararon también los resultados con la actividad según estos., Callinectes sapidus Rathbun (1896) és un crustaci invasor amb origen en la costa est del continent americà, ha estés la seua presència en la costa del Mediterrani amb poblacions establides sobretot al llarg de la costa valenciana i en el delta de l'Ebre. En el present treball s'analitza la capturabilitat o eficiència de captura en aquest cas, així com la capacitat de retenció de les nases que s'estan utilitzant per a la seua captura. L'estudi es va dur a terme en el Barranc de Sant Nicolás, Gandia, zona connectada amb la mar pel port de Gandia i amb aportació d'aigua dolça de les séquies de la marjal. L'anàlisi de la capturabilitat es va determinar mitjançant tècniques de vídeo, els enregistraments de vídeo es van realitzar durant diferents horaris de suposada major i menor activitat segons altres autors i diferents rangs de temperatura i també es van comparar els resultats amb l'activitat segons aquests., Callinectes sapidus (Rathbun 1896) is an invasive crustacean with origin on the east coast of the American continent, it has spread its presence over the Mediterranean coast with established populations especially along the valencian coast and in the Ebro’s delta. This work analyzes the catchability or efficiency of capture in this case, as well as the retention capacity of the traps that are being used for its capture. The study was carried out in the Barranco de San Nicolás, Gandía, an area connected to the sea by the port of Gandía and provided with fresh water from the ditches of the marsh. The catchability analysis was determined using video techniques, the recordings were made during different schedules of supposed higher and lower activity according to other authors and different temperature ranges, and the results were also compared with what was expected according to these autors

Callinectes sapidus Rathbun (1896) es un crustáceo invasor con origen en la costa este del continente americano, ha extendido su presencia en la costa del Mediterráneo con poblaciones establecidas sobre todo a lo largo de la costa valenciana y en el delta del Ebro. En el presente trabajo se analiza la capturabilidad o eficiencia de captura en este caso, así como la capacidad de retención de las nasas que se están usando para su captura. El estudio se llevó a cabo en el Barranco de San Nicolás, Gandía, zona conectada con el mar por el puerto de Gandía y con aporte de agua dulce de las acequias del marjal. El análisis de la capturabilidad se determinó mediante técnicas de vídeo, las grabaciones se realizaron durante distintos horarios de supuesta mayor y menor actividad según otros autores y distintos rangos de temperatura y se compararon también los resultados con la actividad según estos., Callinectes sapidus Rathbun (1896) és un crustaci invasor amb origen en la costa est del continent americà, ha estés la seua presència en la costa del Mediterrani amb poblacions establides sobretot al llarg de la costa valenciana i en el delta de l'Ebre. En el present treball s'analitza la capturabilitat o eficiència de captura en aquest cas, així com la capacitat de retenció de les nases que s'estan utilitzant per a la seua captura. L'estudi es va dur a terme en el Barranc de Sant Nicolás, Gandia, zona connectada amb la mar pel port de Gandia i amb aportació d'aigua dolça de les séquies de la marjal. L'anàlisi de la capturabilitat es va determinar mitjançant tècniques de vídeo, els enregistraments de vídeo es van realitzar durant diferents horaris de suposada major i menor activitat segons altres autors i diferents rangs de temperatura i també es van comparar els resultats amb l'activitat segons aquests., Callinectes sapidus (Rathbun 1896) is an invasive crustacean with origin on the east coast of the American continent, it has spread its presence over the Mediterranean coast with established populations especially along the valencian coast and in the Ebro’s delta. This work analyzes the catchability or efficiency of capture in this case, as well as the retention capacity of the traps that are being used for its capture. The study was carried out in the Barranco de San Nicolás, Gandía, an area connected to the sea by the port of Gandía and provided with fresh water from the ditches of the marsh. The catchability analysis was determined using video techniques, the recordings were made during different schedules of supposed higher and lower activity according to other authors and different temperature ranges, and the results were also compared with what was expected according to these autors

Callinectes sapidus Rathbun (1896) es un crustáceo invasor con origen en la costa este del continente americano, ha extendido su presencia en la costa del Mediterráneo con poblaciones establecidas sobre todo a lo largo de la costa valenciana y en el delta del Ebro. En el presente trabajo se analiza la capturabilidad o eficiencia de captura en este caso, así como la capacidad de retención de las nasas que se están usando para su captura. El estudio se llevó a cabo en el Barranco de San Nicolás, Gandía, zona conectada con el mar por el puerto de Gandía y con aporte de agua dulce de las acequias del marjal. El análisis de la capturabilidad se determinó mediante técnicas de vídeo, las grabaciones se realizaron durante distintos horarios de supuesta mayor y menor actividad según otros autores y distintos rangos de temperatura y se compararon también los resultados con la actividad según estos., Callinectes sapidus Rathbun (1896) és un crustaci invasor amb origen en la costa est del continent americà, ha estés la seua presència en la costa del Mediterrani amb poblacions establides sobretot al llarg de la costa valenciana i en el delta de l'Ebre. En el present treball s'analitza la capturabilitat o eficiència de captura en aquest cas, així com la capacitat de retenció de les nases que s'estan utilitzant per a la seua captura. L'estudi es va dur a terme en el Barranc de Sant Nicolás, Gandia, zona connectada amb la mar pel port de Gandia i amb aportació d'aigua dolça de les séquies de la marjal. L'anàlisi de la capturabilitat es va determinar mitjançant tècniques de vídeo, els enregistraments de vídeo es van realitzar durant diferents horaris de suposada major i menor activitat segons altres autors i diferents rangs de temperatura i també es van comparar els resultats amb l'activitat segons aquests., Callinectes sapidus (Rathbun 1896) is an invasive crustacean with origin on the east coast of the American continent, it has spread its presence over the Mediterranean coast with established populations especially along the valencian coast and in the Ebro’s delta. This work analyzes the catchability or efficiency of capture in this case, as well as the retention capacity of the traps that are being used for its capture. The study was carried out in the Barranco de San Nicolás, Gandía, an area connected to the sea by the port of Gandía and provided with fresh water from the ditches of the marsh. The catchability analysis was determined using video techniques, the recordings were made during different schedules of supposed higher and lower activity according to other authors and different temperature ranges, and the results were also compared with what was expected according to these autors

[ES] Callinectes sapidus (Rathbun 1896), es un voraz crustáceo originario de las costas occidentales del Océano Atlántico, que se ha establecido en distintos lugares del mundo como especie invasora. El objetivo de estudio es estimar la abundancia y su distribución en diferentes hábitats en el Parque Natural de la Albufera de Valencia. Para ello se realizaron muestreos en 3 zonas entre mayo y octubre y se utilizaron técnicas como el marcaje-recaptura, utilizando el modelo Jolly-Seber, y la CPUE. Se encontraron diferencias en la proporción de sexos y tamaños en las diferentes zonas de muestreo así como una diferente distribución a lo largo del periodo de estudio debido a causa de la migración de las hembras al mar para desovar y la permanencia de los machos en aguas menos salinas. En la zona del Perelló se obtuvo una densidad media de 0,03 ind/m2 , dando resultados similares a los de su zona nativa, y la abundancia temporal fluctuó principalmente a causa de la migración y no debido de la intensa actividad pesquera que se registró en el periodo de estudio. En el mes de octubre se encontraron en la Gola del Perelló megalopas y juveniles de esta especie, probablemente proviniendo de las hembras registradas en esta zona a finales del mes de junio., [EN] Callinectes sapidus (Rathbun 1896), is a voracious crustacean native from the western coasts of the Atlantic Ocean, which has established in different parts of the world as an invasive species. The study objective is to estimate abundance and distribution in different habitats in the Albufera of Valencia Natural Park. To do that, samplings were carried out in 3 zones between May and October, and techniques like markingrecapture, using the Jolly-Seber model, and the CPUE were used. Differences were found in the proportion of sexes and sizes at different sampling areas as well as a different distribution along the study period due to the migration of females to the sea to spawn and the permanence of males in less salinity waters. An average density of 0,03 ind/m 2 was obtained in the Perelló area, getting similar results than its native zone, and temporal abundance fluctuated mainly due to migration and not because intense fishing activity that was recorded at the study period. In October megalopae and juvenile of this species were found at the Perelló Gola, probably coming from the females registered in this area at the end of June.

[ES] Callinectes sapidus (Rathbun 1896), es un voraz crustáceo originario de las costas occidentales del Océano Atlántico, que se ha establecido en distintos lugares del mundo como especie invasora. El objetivo de estudio es estimar la abundancia y su distribución en diferentes hábitats en el Parque Natural de la Albufera de Valencia. Para ello se realizaron muestreos en 3 zonas entre mayo y octubre y se utilizaron técnicas como el marcaje-recaptura, utilizando el modelo Jolly-Seber, y la CPUE. Se encontraron diferencias en la proporción de sexos y tamaños en las diferentes zonas de muestreo así como una diferente distribución a lo largo del periodo de estudio debido a causa de la migración de las hembras al mar para desovar y la permanencia de los machos en aguas menos salinas. En la zona del Perelló se obtuvo una densidad media de 0,03 ind/m2 , dando resultados similares a los de su zona nativa, y la abundancia temporal fluctuó principalmente a causa de la migración y no debido de la intensa actividad pesquera que se registró en el periodo de estudio. En el mes de octubre se encontraron en la Gola del Perelló megalopas y juveniles de esta especie, probablemente proviniendo de las hembras registradas en esta zona a finales del mes de junio., [EN] Callinectes sapidus (Rathbun 1896), is a voracious crustacean native from the western coasts of the Atlantic Ocean, which has established in different parts of the world as an invasive species. The study objective is to estimate abundance and distribution in different habitats in the Albufera of Valencia Natural Park. To do that, samplings were carried out in 3 zones between May and October, and techniques like markingrecapture, using the Jolly-Seber model, and the CPUE were used. Differences were found in the proportion of sexes and sizes at different sampling areas as well as a different distribution along the study period due to the migration of females to the sea to spawn and the permanence of males in less salinity waters. An average density of 0,03 ind/m 2 was obtained in the Perelló area, getting similar results than its native zone, and temporal abundance fluctuated mainly due to migration and not because intense fishing activity that was recorded at the study period. In October megalopae and juvenile of this species were found at the Perelló Gola, probably coming from the females registered in this area at the end of June.

[ES] Callinectes sapidus (Rathbun 1896), es un voraz crustáceo originario de las costas occidentales del Océano Atlántico, que se ha establecido en distintos lugares del mundo como especie invasora. El objetivo de estudio es estimar la abundancia y su distribución en diferentes hábitats en el Parque Natural de la Albufera de Valencia. Para ello se realizaron muestreos en 3 zonas entre mayo y octubre y se utilizaron técnicas como el marcaje-recaptura, utilizando el modelo Jolly-Seber, y la CPUE. Se encontraron diferencias en la proporción de sexos y tamaños en las diferentes zonas de muestreo así como una diferente distribución a lo largo del periodo de estudio debido a causa de la migración de las hembras al mar para desovar y la permanencia de los machos en aguas menos salinas. En la zona del Perelló se obtuvo una densidad media de 0,03 ind/m2 , dando resultados similares a los de su zona nativa, y la abundancia temporal fluctuó principalmente a causa de la migración y no debido de la intensa actividad pesquera que se registró en el periodo de estudio. En el mes de octubre se encontraron en la Gola del Perelló megalopas y juveniles de esta especie, probablemente proviniendo de las hembras registradas en esta zona a finales del mes de junio., [EN] Callinectes sapidus (Rathbun 1896), is a voracious crustacean native from the western coasts of the Atlantic Ocean, which has established in different parts of the world as an invasive species. The study objective is to estimate abundance and distribution in different habitats in the Albufera of Valencia Natural Park. To do that, samplings were carried out in 3 zones between May and October, and techniques like markingrecapture, using the Jolly-Seber model, and the CPUE were used. Differences were found in the proportion of sexes and sizes at different sampling areas as well as a different distribution along the study period due to the migration of females to the sea to spawn and the permanence of males in less salinity waters. An average density of 0,03 ind/m 2 was obtained in the Perelló area, getting similar results than its native zone, and temporal abundance fluctuated mainly due to migration and not because intense fishing activity that was recorded at the study period. In October megalopae and juvenile of this species were found at the Perelló Gola, probably coming from the females registered in this area at the end of June.

[ES] Callinectes sapidus (Rathbun 1896), es un voraz crustáceo originario de las costas occidentales del Océano Atlántico, que se ha establecido en distintos lugares del mundo como especie invasora. El objetivo de estudio es estimar la abundancia y su distribución en diferentes hábitats en el Parque Natural de la Albufera de Valencia. Para ello se realizaron muestreos en 3 zonas entre mayo y octubre y se utilizaron técnicas como el marcaje-recaptura, utilizando el modelo Jolly-Seber, y la CPUE. Se encontraron diferencias en la proporción de sexos y tamaños en las diferentes zonas de muestreo así como una diferente distribución a lo largo del periodo de estudio debido a causa de la migración de las hembras al mar para desovar y la permanencia de los machos en aguas menos salinas. En la zona del Perelló se obtuvo una densidad media de 0,03 ind/m2 , dando resultados similares a los de su zona nativa, y la abundancia temporal fluctuó principalmente a causa de la migración y no debido de la intensa actividad pesquera que se registró en el periodo de estudio. En el mes de octubre se encontraron en la Gola del Perelló megalopas y juveniles de esta especie, probablemente proviniendo de las hembras registradas en esta zona a finales del mes de junio., [EN] Callinectes sapidus (Rathbun 1896), is a voracious crustacean native from the western coasts of the Atlantic Ocean, which has established in different parts of the world as an invasive species. The study objective is to estimate abundance and distribution in different habitats in the Albufera of Valencia Natural Park. To do that, samplings were carried out in 3 zones between May and October, and techniques like markingrecapture, using the Jolly-Seber model, and the CPUE were used. Differences were found in the proportion of sexes and sizes at different sampling areas as well as a different distribution along the study period due to the migration of females to the sea to spawn and the permanence of males in less salinity waters. An average density of 0,03 ind/m 2 was obtained in the Perelló area, getting similar results than its native zone, and temporal abundance fluctuated mainly due to migration and not because intense fishing activity that was recorded at the study period. In October megalopae and juvenile of this species were found at the Perelló Gola, probably coming from the females registered in this area at the end of June.

[ES] Callinectes sapidus (Rathbun 1896), es un voraz crustáceo originario de las costas occidentales del Océano Atlántico, que se ha establecido en distintos lugares del mundo como especie invasora. El objetivo de estudio es estimar la abundancia y su distribución en diferentes hábitats en el Parque Natural de la Albufera de Valencia. Para ello se realizaron muestreos en 3 zonas entre mayo y octubre y se utilizaron técnicas como el marcaje-recaptura, utilizando el modelo Jolly-Seber, y la CPUE. Se encontraron diferencias en la proporción de sexos y tamaños en las diferentes zonas de muestreo así como una diferente distribución a lo largo del periodo de estudio debido a causa de la migración de las hembras al mar para desovar y la permanencia de los machos en aguas menos salinas. En la zona del Perelló se obtuvo una densidad media de 0,03 ind/m2 , dando resultados similares a los de su zona nativa, y la abundancia temporal fluctuó principalmente a causa de la migración y no debido de la intensa actividad pesquera que se registró en el periodo de estudio. En el mes de octubre se encontraron en la Gola del Perelló megalopas y juveniles de esta especie, probablemente proviniendo de las hembras registradas en esta zona a finales del mes de junio., [EN] Callinectes sapidus (Rathbun 1896), is a voracious crustacean native from the western coasts of the Atlantic Ocean, which has established in different parts of the world as an invasive species. The study objective is to estimate abundance and distribution in different habitats in the Albufera of Valencia Natural Park. To do that, samplings were carried out in 3 zones between May and October, and techniques like markingrecapture, using the Jolly-Seber model, and the CPUE were used. Differences were found in the proportion of sexes and sizes at different sampling areas as well as a different distribution along the study period due to the migration of females to the sea to spawn and the permanence of males in less salinity waters. An average density of 0,03 ind/m 2 was obtained in the Perelló area, getting similar results than its native zone, and temporal abundance fluctuated mainly due to migration and not because intense fishing activity that was recorded at the study period. In October megalopae and juvenile of this species were found at the Perelló Gola, probably coming from the females registered in this area at the end of June.

The aim of this study was to evaluate Cd and Pb concentrations in the hepatopancreas, gills, muscle tissue and carapace of the crab Callinectes sapidus and in sediments from the mouth of the river Segura (SE Spain), an area that has undergone great anthropogenic change in recent decades. Lead concentrations were higher than Cd concentrations in the hepatopancreas, gills and muscles; no statistical differences were found between the sexes. Cadmium and Pb concentrations in sediments did not exceed the probable effect level in guidelines for the protection of aquatic life. The Biological Sediments Accumulation Factor (BSAF) was higher for Cd than Pb in the hepatopancreas, gills and carapace. For Cd, the hepatopancreas had the highest BSAF of all tissues, followed by gills. As well, the hepatopancreas had the highest Individual Mean Bioaccumulation Index (IMBI). The hepatopancreas and gills of the blue crab could thus be useful tissues for practical field monitoring of metal contamination in this ecosystem.

[ES] El cangrejo azul, Callinectes sapidus Rathbun (1896), es nativo de la costa occidental del Océano Atlántico, se trata de una especie migratoria que necesita ambientes marinos y estuarinos para completar su ciclo de vida. Callinectes sapidus es una especie invasora en la costa mediterránea, que al no tener depredadores naturales está causando grandes daños ecosistémicos, por lo que su estudio y comprensión es muy importante. El estudio presente se realizó en una pequeña zona estuarina, el barranco de San Nicolás en Gandía y la zona marina adyacente. Brinda información sobre la clara segregación por sexos de la zona, encontrando mayor número de machos que de hembras en la zona estuarina, lo cual coincide con la información biológica existente de la especie. También se demuestra que la zona de estudio es un sistema abierto donde la población de C. sapidus está establecida y se encuentra en equilibrio y en el límite de su capacidad de carga. Se determinaron las fechas y zonas donde se sitúan los diferentes estadios de la especie., [EN] The blue crab, Callinectes sapidus Rathbun (1896), is native of the western coast of the Atlantic Ocean, it’s a migratory species that needs marine and estuarine environments to compete its life cycle. Callinectes sapidus is an invasive species on the Mediterranean coasts, which by not having natural predators is causing great damage in the ecosystems, so its study and understanding is very important. The present study was carried out in a small estuarine area, the San Nicolás ravine in Gandía and the adjacent marine zone. It provides information on the clear segregation by sex of the area, finding a greater number of males than females in the estuarine zone, which coincides with the existing biological information of the species. It is also shown that the study area is an open system where the population of C. sapidus is established, in equilibrium and at the limit of its carrying capacity. The dates and areas where the different stages of the species were located were also determined.

[ES] El cangrejo azul, Callinectes sapidus Rathbun (1896), es nativo de la costa occidental del Océano Atlántico, se trata de una especie migratoria que necesita ambientes marinos y estuarinos para completar su ciclo de vida. Callinectes sapidus es una especie invasora en la costa mediterránea, que al no tener depredadores naturales está causando grandes daños ecosistémicos, por lo que su estudio y comprensión es muy importante. El estudio presente se realizó en una pequeña zona estuarina, el barranco de San Nicolás en Gandía y la zona marina adyacente. Brinda información sobre la clara segregación por sexos de la zona, encontrando mayor número de machos que de hembras en la zona estuarina, lo cual coincide con la información biológica existente de la especie. También se demuestra que la zona de estudio es un sistema abierto donde la población de C. sapidus está establecida y se encuentra en equilibrio y en el límite de su capacidad de carga. Se determinaron las fechas y zonas donde se sitúan los diferentes estadios de la especie., [EN] The blue crab, Callinectes sapidus Rathbun (1896), is native of the western coast of the Atlantic Ocean, it’s a migratory species that needs marine and estuarine environments to compete its life cycle. Callinectes sapidus is an invasive species on the Mediterranean coasts, which by not having natural predators is causing great damage in the ecosystems, so its study and understanding is very important. The present study was carried out in a small estuarine area, the San Nicolás ravine in Gandía and the adjacent marine zone. It provides information on the clear segregation by sex of the area, finding a greater number of males than females in the estuarine zone, which coincides with the existing biological information of the species. It is also shown that the study area is an open system where the population of C. sapidus is established, in equilibrium and at the limit of its carrying capacity. The dates and areas where the different stages of the species were located were also determined.

[ES] El cangrejo azul, Callinectes sapidus Rathbun (1896), es nativo de la costa occidental del Océano Atlántico, se trata de una especie migratoria que necesita ambientes marinos y estuarinos para completar su ciclo de vida. Callinectes sapidus es una especie invasora en la costa mediterránea, que al no tener depredadores naturales está causando grandes daños ecosistémicos, por lo que su estudio y comprensión es muy importante. El estudio presente se realizó en una pequeña zona estuarina, el barranco de San Nicolás en Gandía y la zona marina adyacente. Brinda información sobre la clara segregación por sexos de la zona, encontrando mayor número de machos que de hembras en la zona estuarina, lo cual coincide con la información biológica existente de la especie. También se demuestra que la zona de estudio es un sistema abierto donde la población de C. sapidus está establecida y se encuentra en equilibrio y en el límite de su capacidad de carga. Se determinaron las fechas y zonas donde se sitúan los diferentes estadios de la especie., [EN] The blue crab, Callinectes sapidus Rathbun (1896), is native of the western coast of the Atlantic Ocean, it’s a migratory species that needs marine and estuarine environments to compete its life cycle. Callinectes sapidus is an invasive species on the Mediterranean coasts, which by not having natural predators is causing great damage in the ecosystems, so its study and understanding is very important. The present study was carried out in a small estuarine area, the San Nicolás ravine in Gandía and the adjacent marine zone. It provides information on the clear segregation by sex of the area, finding a greater number of males than females in the estuarine zone, which coincides with the existing biological information of the species. It is also shown that the study area is an open system where the population of C. sapidus is established, in equilibrium and at the limit of its carrying capacity. The dates and areas where the different stages of the species were located were also determined.

[ES] El cangrejo azul, Callinectes sapidus Rathbun (1896), es nativo de la costa occidental del Océano Atlántico, se trata de una especie migratoria que necesita ambientes marinos y estuarinos para completar su ciclo de vida. Callinectes sapidus es una especie invasora en la costa mediterránea, que al no tener depredadores naturales está causando grandes daños ecosistémicos, por lo que su estudio y comprensión es muy importante. El estudio presente se realizó en una pequeña zona estuarina, el barranco de San Nicolás en Gandía y la zona marina adyacente. Brinda información sobre la clara segregación por sexos de la zona, encontrando mayor número de machos que de hembras en la zona estuarina, lo cual coincide con la información biológica existente de la especie. También se demuestra que la zona de estudio es un sistema abierto donde la población de C. sapidus está establecida y se encuentra en equilibrio y en el límite de su capacidad de carga. Se determinaron las fechas y zonas donde se sitúan los diferentes estadios de la especie., [EN] The blue crab, Callinectes sapidus Rathbun (1896), is native of the western coast of the Atlantic Ocean, it’s a migratory species that needs marine and estuarine environments to compete its life cycle. Callinectes sapidus is an invasive species on the Mediterranean coasts, which by not having natural predators is causing great damage in the ecosystems, so its study and understanding is very important. The present study was carried out in a small estuarine area, the San Nicolás ravine in Gandía and the adjacent marine zone. It provides information on the clear segregation by sex of the area, finding a greater number of males than females in the estuarine zone, which coincides with the existing biological information of the species. It is also shown that the study area is an open system where the population of C. sapidus is established, in equilibrium and at the limit of its carrying capacity. The dates and areas where the different stages of the species were located were also determined.

In this report are described abundance, size structure, and relative growth in Callinectes sapidus young stages from the Laguna El Llano blind estuary, Veracruz State (Mexico). Blue crabs were sampled in eight sampling sites since May 2013 to May 2014; four sites were located in un-vegetated, sandy bottom, and clear waters locations near to estuarine inlet, another four with fringe mangrove vegetation, muddy-bottom, and turbid waters. Were recorded pH, temperature, dissolved oxygen, turbidity, and salinity. A total of 276 organisms were collected (235 males and 41 females), young blue crabs were most numerous (91.3 %) in muddy-bottom, turbid waters sampling sites; the temporal abundance was not related statistically to hydrological variables (P >0.05). Were measured the Carapace Width (CW) and total weight (W) of each specimen, male CW ranked 12–85 mm and WW 0.3–123.4 g, while female CW was 9.0–92.8 mm and W 0.7–152.6 g; respect to total abundance, 76.4 % were 11–20 mm and 41–60 mm CW size class specimens; the relative growth was analyzed by using CW vs. W biometric relationship, for young blue crabs were negative allometric growth, regardless of sex; all specimens showed morphologically differentiated telson but early gonadal development stages; males outnumbered the gender proportion; 11–20 mm CW blue crabs occurrence through study span indicated continuous recruitment processes in this estuary., En este estudio se describe la abundancia, composición por tallas y crecimiento relativo de organismos juveniles de la jaiba Callinectes sapidus en el estuario ciego Laguna El Llano, Veracruz, México; las jaibas se muestrearon desde mayo de 2013 hasta mayo de 2014 en ocho sitios, cuatro sin vegetación, con sedimentos arenosos y aguas claras cercanos a la boca estuarina, los restantes con vegetación de manglar, sedimentos lodosos y aguas turbias. Se registraron las variables hidrológicas pH, temperatura, oxígeno disuelto, turbidez y salinidad. Se recolectaron 276 jaibas (235 machos y 41 hembras), la abundancia fue mayor (91,3 %) en los sitios cercanos a manglares, sedimentos lodosos y aguas turbias; la abundancia no se relacionó con las variables hidrológicas (P > 0,05). Por individuo se midió el ancho de caparazón (AC) y peso (P); los machos se registraron en un intervalo de AC entre 12 y 85 mm y de 0,3 a 123,4 g, las hembras se recolectaron entre 9 y 92,8 mm AC y pesaron entre 0,7 a 152,6 g; 76,4 % de los especímenes correspondieron a tallas de 11 a 40 mm AC; se analizó el crecimiento relativo usando la relación biométrica AC vs. P, que para las jaibas jóvenes fue alométrica negativa independientemente del sexo; todos los individuos presentaron el telson diferenciado pero en etapas iniciales de desarrollo gonádico, la proporción sexual fue dominada por los machos; la ocurrencia de la talla de 11 a 20 mm AC durante el estudio indicó reclutamiento continuo al estuario.

In this report are described abundance, size structure, and relative growth in Callinectes sapidus young stages from the Laguna El Llano blind estuary, Veracruz State (Mexico). Blue crabs were sampled in eight sampling sites since May 2013 to May 2014; four sites were located in un-vegetated, sandy bottom, and clear waters locations near to estuarine inlet, another four with fringe mangrove vegetation, muddy-bottom, and turbid waters. Were recorded pH, temperature, dissolved oxygen, turbidity, and salinity. A total of 276 organisms were collected (235 males and 41 females), young blue crabs were most numerous (91.3 %) in muddy-bottom, turbid waters sampling sites; the temporal abundance was not related statistically to hydrological variables (P >0.05). Were measured the Carapace Width (CW) and total weight (W) of each specimen, male CW ranked 12–85 mm and WW 0.3–123.4 g, while female CW was 9.0–92.8 mm and W 0.7–152.6 g; respect to total abundance, 76.4 % were 11–20 mm and 41–60 mm CW size class specimens; the relative growth was analyzed by using CW vs. W biometric relationship, for young blue crabs were negative allometric growth, regardless of sex; all specimens showed morphologically differentiated telson but early gonadal development stages; males outnumbered the gender proportion; 11–20 mm CW blue crabs occurrence through study span indicated continuous recruitment processes in this estuary., En este estudio se describe la abundancia, composición por tallas y crecimiento relativo de organismos juveniles de la jaiba Callinectes sapidus en el estuario ciego Laguna El Llano, Veracruz, México; las jaibas se muestrearon desde mayo de 2013 hasta mayo de 2014 en ocho sitios, cuatro sin vegetación, con sedimentos arenosos y aguas claras cercanos a la boca estuarina, los restantes con vegetación de manglar, sedimentos lodosos y aguas turbias. Se registraron las variables hidrológicas pH, temperatura, oxígeno disuelto, turbidez y salinidad. Se recolectaron 276 jaibas (235 machos y 41 hembras), la abundancia fue mayor (91,3 %) en los sitios cercanos a manglares, sedimentos lodosos y aguas turbias; la abundancia no se relacionó con las variables hidrológicas (P > 0,05). Por individuo se midió el ancho de caparazón (AC) y peso (P); los machos se registraron en un intervalo de AC entre 12 y 85 mm y de 0,3 a 123,4 g, las hembras se recolectaron entre 9 y 92,8 mm AC y pesaron entre 0,7 a 152,6 g; 76,4 % de los especímenes correspondieron a tallas de 11 a 40 mm AC; se analizó el crecimiento relativo usando la relación biométrica AC vs. P, que para las jaibas jóvenes fue alométrica negativa independientemente del sexo; todos los individuos presentaron el telson diferenciado pero en etapas iniciales de desarrollo gonádico, la proporción sexual fue dominada por los machos; la ocurrencia de la talla de 11 a 20 mm AC durante el estudio indicó reclutamiento continuo al estuario.

In this report are described abundance, size structure, and relative growth in Callinectes sapidus young stages from the Laguna El Llano blind estuary, Veracruz State (Mexico). Blue crabs were sampled in eight sampling sites since May 2013 to May 2014; four sites were located in un-vegetated, sandy bottom, and clear waters locations near to estuarine inlet, another four with fringe mangrove vegetation, muddy-bottom, and turbid waters. Were recorded pH, temperature, dissolved oxygen, turbidity, and salinity. A total of 276 organisms were collected (235 males and 41 females), young blue crabs were most numerous (91.3 %) in muddy-bottom, turbid waters sampling sites; the temporal abundance was not related statistically to hydrological variables (P >0.05). Were measured the Carapace Width (CW) and total weight (W) of each specimen, male CW ranked 12–85 mm and WW 0.3–123.4 g, while female CW was 9.0–92.8 mm and W 0.7–152.6 g; respect to total abundance, 76.4 % were 11–20 mm and 41–60 mm CW size class specimens; the relative growth was analyzed by using CW vs. W biometric relationship, for young blue crabs were negative allometric growth, regardless of sex; all specimens showed morphologically differentiated telson but early gonadal development stages; males outnumbered the gender proportion; 11–20 mm CW blue crabs occurrence through study span indicated continuous recruitment processes in this estuary., En este estudio se describe la abundancia, composición por tallas y crecimiento relativo de organismos juveniles de la jaiba Callinectes sapidus en el estuario ciego Laguna El Llano, Veracruz, México; las jaibas se muestrearon desde mayo de 2013 hasta mayo de 2014 en ocho sitios, cuatro sin vegetación, con sedimentos arenosos y aguas claras cercanos a la boca estuarina, los restantes con vegetación de manglar, sedimentos lodosos y aguas turbias. Se registraron las variables hidrológicas pH, temperatura, oxígeno disuelto, turbidez y salinidad. Se recolectaron 276 jaibas (235 machos y 41 hembras), la abundancia fue mayor (91,3 %) en los sitios cercanos a manglares, sedimentos lodosos y aguas turbias; la abundancia no se relacionó con las variables hidrológicas (P > 0,05). Por individuo se midió el ancho de caparazón (AC) y peso (P); los machos se registraron en un intervalo de AC entre 12 y 85 mm y de 0,3 a 123,4 g, las hembras se recolectaron entre 9 y 92,8 mm AC y pesaron entre 0,7 a 152,6 g; 76,4 % de los especímenes correspondieron a tallas de 11 a 40 mm AC; se analizó el crecimiento relativo usando la relación biométrica AC vs. P, que para las jaibas jóvenes fue alométrica negativa independientemente del sexo; todos los individuos presentaron el telson diferenciado pero en etapas iniciales de desarrollo gonádico, la proporción sexual fue dominada por los machos; la ocurrencia de la talla de 11 a 20 mm AC durante el estudio indicó reclutamiento continuo al estuario.

In this report are described abundance, size structure, and relative growth in Callinectes sapidus young stages from the Laguna El Llano blind estuary, Veracruz State (Mexico). Blue crabs were sampled in eight sampling sites since May 2013 to May 2014; four sites were located in un-vegetated, sandy bottom, and clear waters locations near to estuarine inlet, another four with fringe mangrove vegetation, muddy-bottom, and turbid waters. Were recorded pH, temperature, dissolved oxygen, turbidity, and salinity. A total of 276 organisms were collected (235 males and 41 females), young blue crabs were most numerous (91.3 %) in muddy-bottom, turbid waters sampling sites; the temporal abundance was not related statistically to hydrological variables (P >0.05). Were measured the Carapace Width (CW) and total weight (W) of each specimen, male CW ranked 12–85 mm and WW 0.3–123.4 g, while female CW was 9.0–92.8 mm and W 0.7–152.6 g; respect to total abundance, 76.4 % were 11–20 mm and 41–60 mm CW size class specimens; the relative growth was analyzed by using CW vs. W biometric relationship, for young blue crabs were negative allometric growth, regardless of sex; all specimens showed morphologically differentiated telson but early gonadal development stages; males outnumbered the gender proportion; 11–20 mm CW blue crabs occurrence through study span indicated continuous recruitment processes in this estuary., En este estudio se describe la abundancia, composición por tallas y crecimiento relativo de organismos juveniles de la jaiba Callinectes sapidus en el estuario ciego Laguna El Llano, Veracruz, México; las jaibas se muestrearon desde mayo de 2013 hasta mayo de 2014 en ocho sitios, cuatro sin vegetación, con sedimentos arenosos y aguas claras cercanos a la boca estuarina, los restantes con vegetación de manglar, sedimentos lodosos y aguas turbias. Se registraron las variables hidrológicas pH, temperatura, oxígeno disuelto, turbidez y salinidad. Se recolectaron 276 jaibas (235 machos y 41 hembras), la abundancia fue mayor (91,3 %) en los sitios cercanos a manglares, sedimentos lodosos y aguas turbias; la abundancia no se relacionó con las variables hidrológicas (P > 0,05). Por individuo se midió el ancho de caparazón (AC) y peso (P); los machos se registraron en un intervalo de AC entre 12 y 85 mm y de 0,3 a 123,4 g, las hembras se recolectaron entre 9 y 92,8 mm AC y pesaron entre 0,7 a 152,6 g; 76,4 % de los especímenes correspondieron a tallas de 11 a 40 mm AC; se analizó el crecimiento relativo usando la relación biométrica AC vs. P, que para las jaibas jóvenes fue alométrica negativa independientemente del sexo; todos los individuos presentaron el telson diferenciado pero en etapas iniciales de desarrollo gonádico, la proporción sexual fue dominada por los machos; la ocurrencia de la talla de 11 a 20 mm AC durante el estudio indicó reclutamiento continuo al estuario.

C. sapidus es un voraz y agresivo crustáceo decápodo que se ha asentado en distintos lugares alrededor del mundo como especie invasora. Debido a que puede alcanzar altas densidades de población resulta primordial identificar los impactos que provoca sobre el ecosistema autóctono. En este trabajo se realiza un análisis de contenidos estomacales para determinar la dieta de C. sapidus en dos puntos de la costa mediterránea española, el Delta del Ebro y Gandía. Otros puntos de muestreo fueron explorados y descartados por diversos motivos. Para determinar la importancia de las distintas categorías de contenidos estomacales se empleó un índice compuesto. Los resultados revelan una diferencia importante entre puntos de muestreo y tallas, sin embargo, no fue posible establecer si existían diferencias entre sexos debido a que se capturaron mayoritariamente machos. Existe una diferencia muy clara entre la dieta de los ambientes invadidos y la dieta de su entorno nativo, sin embargo, los cangrejos parecen crecer de modo muy similar al determinado por otros autores. Se determinaron los puntos fuertes y débiles de distintas técnicas de captura, y se exploran una serie de futuras líneas de actuación para determinar el impacto que causan en el ecosistema con mayor precisión, C. sapidus is a voracious and aggressive decapod crustacean that has settled in different places around the world as an invasive species. Because it can reach high population densities, it is essential to identify the impacts it causes on the native ecosystem. In this study an analysis of stomach contents is carried out to determine the diet of C. sapidus in two points of the spanish mediterranean coast, the Ebro Delta and Gandía. Other sampling points were explored and discarded for various reasons. To determine the importance of the different categories of stomach contents, a compound index was used. The results reveal an important difference between sampling points and sizes, however, it was not possible to establish if there were differences between sexes because most captures were males. There is a very clear difference between the diet of the invaded environments and the diet of their native environment, however, the crabs seem to grow in a very similar way to that determined by other authors. The strengths and weaknesses of different capture techniques were determined, and a series of future lines of action are explored to determine the impact they cause on the ecosystem with greater precision.

C. sapidus es un voraz y agresivo crustáceo decápodo que se ha asentado en distintos lugares alrededor del mundo como especie invasora. Debido a que puede alcanzar altas densidades de población resulta primordial identificar los impactos que provoca sobre el ecosistema autóctono. En este trabajo se realiza un análisis de contenidos estomacales para determinar la dieta de C. sapidus en dos puntos de la costa mediterránea española, el Delta del Ebro y Gandía. Otros puntos de muestreo fueron explorados y descartados por diversos motivos. Para determinar la importancia de las distintas categorías de contenidos estomacales se empleó un índice compuesto. Los resultados revelan una diferencia importante entre puntos de muestreo y tallas, sin embargo, no fue posible establecer si existían diferencias entre sexos debido a que se capturaron mayoritariamente machos. Existe una diferencia muy clara entre la dieta de los ambientes invadidos y la dieta de su entorno nativo, sin embargo, los cangrejos parecen crecer de modo muy similar al determinado por otros autores. Se determinaron los puntos fuertes y débiles de distintas técnicas de captura, y se exploran una serie de futuras líneas de actuación para determinar el impacto que causan en el ecosistema con mayor precisión, C. sapidus is a voracious and aggressive decapod crustacean that has settled in different places around the world as an invasive species. Because it can reach high population densities, it is essential to identify the impacts it causes on the native ecosystem. In this study an analysis of stomach contents is carried out to determine the diet of C. sapidus in two points of the spanish mediterranean coast, the Ebro Delta and Gandía. Other sampling points were explored and discarded for various reasons. To determine the importance of the different categories of stomach contents, a compound index was used. The results reveal an important difference between sampling points and sizes, however, it was not possible to establish if there were differences between sexes because most captures were males. There is a very clear difference between the diet of the invaded environments and the diet of their native environment, however, the crabs seem to grow in a very similar way to that determined by other authors. The strengths and weaknesses of different capture techniques were determined, and a series of future lines of action are explored to determine the impact they cause on the ecosystem with greater precision.

En este estudio, se comprenden datos e información sobre el cangrejo azul americano, así como su influencia y carácter invasor que actualmente están percibiendo las costas del Mediterráneo. El objetivo principal de este documento, es comprender el comportamiento de la especie C.sapidus, mediante un estudio de diferentes fuentes bibliográficas e incorporando información de las personas que rodean su hábitat y en consecuencia más les afecta su presencia como son los arroceros, pescadores y personal especializado en especies invasoras. De esa manera conocer mejor que impactos puede contener este cangrejo, así como tener conocimiento de si la gente está concienciada de los problemas que puede suponer en el ecosistema. Una vez comprendamos la situación de la especie, estudiaremos si es necesaria una actuación o no contra esta especie, y si es así, estudiar qué actuación sería la mejor para su erradicación, control o gestión, basándonos en la información obtenida y las entrevistas, incluyendo la posibilidad de comercialización a gran escala sin límite de tallas, para su gestión., In this study, data and information about the American blue crab are understood, as well as its influence and invasive character that are currently perceiving the coasts of the Mediterranean. The main objective of this document is to understand the behavior of the species C. sapidus, by means of a study of different bibliographical sources and incorporating information of the people that surround their habitat and as a consequence they are more affected by their presence such as rice farmers, fishermen and staff specialized in invasive species. In this way, to know better what impacts this crab may contain, as well as to have knowledge of if people are aware of the problems that may arise in the ecosystem. Once we understand the situation of the species, we will study if an action is necessary or not against this species, and if so, study what action would be the best for its eradication, control or management, based on the information obtained and the interviews, including the possibility of commercialization on a large scale without size limit, for its management.

En este estudio, se comprenden datos e información sobre el cangrejo azul americano, así como su influencia y carácter invasor que actualmente están percibiendo las costas del Mediterráneo. El objetivo principal de este documento, es comprender el comportamiento de la especie C.sapidus, mediante un estudio de diferentes fuentes bibliográficas e incorporando información de las personas que rodean su hábitat y en consecuencia más les afecta su presencia como son los arroceros, pescadores y personal especializado en especies invasoras. De esa manera conocer mejor que impactos puede contener este cangrejo, así como tener conocimiento de si la gente está concienciada de los problemas que puede suponer en el ecosistema. Una vez comprendamos la situación de la especie, estudiaremos si es necesaria una actuación o no contra esta especie, y si es así, estudiar qué actuación sería la mejor para su erradicación, control o gestión, basándonos en la información obtenida y las entrevistas, incluyendo la posibilidad de comercialización a gran escala sin límite de tallas, para su gestión., In this study, data and information about the American blue crab are understood, as well as its influence and invasive character that are currently perceiving the coasts of the Mediterranean. The main objective of this document is to understand the behavior of the species C. sapidus, by means of a study of different bibliographical sources and incorporating information of the people that surround their habitat and as a consequence they are more affected by their presence such as rice farmers, fishermen and staff specialized in invasive species. In this way, to know better what impacts this crab may contain, as well as to have knowledge of if people are aware of the problems that may arise in the ecosystem. Once we understand the situation of the species, we will study if an action is necessary or not against this species, and if so, study what action would be the best for its eradication, control or management, based on the information obtained and the interviews, including the possibility of commercialization on a large scale without size limit, for its management.

C. sapidus es un voraz y agresivo crustáceo decápodo que se ha asentado en distintos lugares alrededor del mundo como especie invasora. Debido a que puede alcanzar altas densidades de población resulta primordial identificar los impactos que provoca sobre el ecosistema autóctono. En este trabajo se realiza un análisis de contenidos estomacales para determinar la dieta de C. sapidus en dos puntos de la costa mediterránea española, el Delta del Ebro y Gandía. Otros puntos de muestreo fueron explorados y descartados por diversos motivos. Para determinar la importancia de las distintas categorías de contenidos estomacales se empleó un índice compuesto. Los resultados revelan una diferencia importante entre puntos de muestreo y tallas, sin embargo, no fue posible establecer si existían diferencias entre sexos debido a que se capturaron mayoritariamente machos. Existe una diferencia muy clara entre la dieta de los ambientes invadidos y la dieta de su entorno nativo, sin embargo, los cangrejos parecen crecer de modo muy similar al determinado por otros autores. Se determinaron los puntos fuertes y débiles de distintas técnicas de captura, y se exploran una serie de futuras líneas de actuación para determinar el impacto que causan en el ecosistema con mayor precisión, C. sapidus is a voracious and aggressive decapod crustacean that has settled in different places around the world as an invasive species. Because it can reach high population densities, it is essential to identify the impacts it causes on the native ecosystem. In this study an analysis of stomach contents is carried out to determine the diet of C. sapidus in two points of the spanish mediterranean coast, the Ebro Delta and Gandía. Other sampling points were explored and discarded for various reasons. To determine the importance of the different categories of stomach contents, a compound index was used. The results reveal an important difference between sampling points and sizes, however, it was not possible to establish if there were differences between sexes because most captures were males. There is a very clear difference between the diet of the invaded environments and the diet of their native environment, however, the crabs seem to grow in a very similar way to that determined by other authors. The strengths and weaknesses of different capture techniques were determined, and a series of future lines of action are explored to determine the impact they cause on the ecosystem with greater precision.

En este estudio, se comprenden datos e información sobre el cangrejo azul americano, así como su influencia y carácter invasor que actualmente están percibiendo las costas del Mediterráneo. El objetivo principal de este documento, es comprender el comportamiento de la especie C.sapidus, mediante un estudio de diferentes fuentes bibliográficas e incorporando información de las personas que rodean su hábitat y en consecuencia más les afecta su presencia como son los arroceros, pescadores y personal especializado en especies invasoras. De esa manera conocer mejor que impactos puede contener este cangrejo, así como tener conocimiento de si la gente está concienciada de los problemas que puede suponer en el ecosistema. Una vez comprendamos la situación de la especie, estudiaremos si es necesaria una actuación o no contra esta especie, y si es así, estudiar qué actuación sería la mejor para su erradicación, control o gestión, basándonos en la información obtenida y las entrevistas, incluyendo la posibilidad de comercialización a gran escala sin límite de tallas, para su gestión., In this study, data and information about the American blue crab are understood, as well as its influence and invasive character that are currently perceiving the coasts of the Mediterranean. The main objective of this document is to understand the behavior of the species C. sapidus, by means of a study of different bibliographical sources and incorporating information of the people that surround their habitat and as a consequence they are more affected by their presence such as rice farmers, fishermen and staff specialized in invasive species. In this way, to know better what impacts this crab may contain, as well as to have knowledge of if people are aware of the problems that may arise in the ecosystem. Once we understand the situation of the species, we will study if an action is necessary or not against this species, and if so, study what action would be the best for its eradication, control or management, based on the information obtained and the interviews, including the possibility of commercialization on a large scale without size limit, for its management.

C. sapidus es un voraz y agresivo crustáceo decápodo que se ha asentado en distintos lugares alrededor del mundo como especie invasora. Debido a que puede alcanzar altas densidades de población resulta primordial identificar los impactos que provoca sobre el ecosistema autóctono. En este trabajo se realiza un análisis de contenidos estomacales para determinar la dieta de C. sapidus en dos puntos de la costa mediterránea española, el Delta del Ebro y Gandía. Otros puntos de muestreo fueron explorados y descartados por diversos motivos. Para determinar la importancia de las distintas categorías de contenidos estomacales se empleó un índice compuesto. Los resultados revelan una diferencia importante entre puntos de muestreo y tallas, sin embargo, no fue posible establecer si existían diferencias entre sexos debido a que se capturaron mayoritariamente machos. Existe una diferencia muy clara entre la dieta de los ambientes invadidos y la dieta de su entorno nativo, sin embargo, los cangrejos parecen crecer de modo muy similar al determinado por otros autores. Se determinaron los puntos fuertes y débiles de distintas técnicas de captura, y se exploran una serie de futuras líneas de actuación para determinar el impacto que causan en el ecosistema con mayor precisión, C. sapidus is a voracious and aggressive decapod crustacean that has settled in different places around the world as an invasive species. Because it can reach high population densities, it is essential to identify the impacts it causes on the native ecosystem. In this study an analysis of stomach contents is carried out to determine the diet of C. sapidus in two points of the spanish mediterranean coast, the Ebro Delta and Gandía. Other sampling points were explored and discarded for various reasons. To determine the importance of the different categories of stomach contents, a compound index was used. The results reveal an important difference between sampling points and sizes, however, it was not possible to establish if there were differences between sexes because most captures were males. There is a very clear difference between the diet of the invaded environments and the diet of their native environment, however, the crabs seem to grow in a very similar way to that determined by other authors. The strengths and weaknesses of different capture techniques were determined, and a series of future lines of action are explored to determine the impact they cause on the ecosystem with greater precision.

C. sapidus es un voraz y agresivo crustáceo decápodo que se ha asentado en distintos lugares alrededor del mundo como especie invasora. Debido a que puede alcanzar altas densidades de población resulta primordial identificar los impactos que provoca sobre el ecosistema autóctono. En este trabajo se realiza un análisis de contenidos estomacales para determinar la dieta de C. sapidus en dos puntos de la costa mediterránea española, el Delta del Ebro y Gandía. Otros puntos de muestreo fueron explorados y descartados por diversos motivos. Para determinar la importancia de las distintas categorías de contenidos estomacales se empleó un índice compuesto. Los resultados revelan una diferencia importante entre puntos de muestreo y tallas, sin embargo, no fue posible establecer si existían diferencias entre sexos debido a que se capturaron mayoritariamente machos. Existe una diferencia muy clara entre la dieta de los ambientes invadidos y la dieta de su entorno nativo, sin embargo, los cangrejos parecen crecer de modo muy similar al determinado por otros autores. Se determinaron los puntos fuertes y débiles de distintas técnicas de captura, y se exploran una serie de futuras líneas de actuación para determinar el impacto que causan en el ecosistema con mayor precisión, C. sapidus is a voracious and aggressive decapod crustacean that has settled in different places around the world as an invasive species. Because it can reach high population densities, it is essential to identify the impacts it causes on the native ecosystem. In this study an analysis of stomach contents is carried out to determine the diet of C. sapidus in two points of the spanish mediterranean coast, the Ebro Delta and Gandía. Other sampling points were explored and discarded for various reasons. To determine the importance of the different categories of stomach contents, a compound index was used. The results reveal an important difference between sampling points and sizes, however, it was not possible to establish if there were differences between sexes because most captures were males. There is a very clear difference between the diet of the invaded environments and the diet of their native environment, however, the crabs seem to grow in a very similar way to that determined by other authors. The strengths and weaknesses of different capture techniques were determined, and a series of future lines of action are explored to determine the impact they cause on the ecosystem with greater precision.

En este estudio, se comprenden datos e información sobre el cangrejo azul americano, así como su influencia y carácter invasor que actualmente están percibiendo las costas del Mediterráneo. El objetivo principal de este documento, es comprender el comportamiento de la especie C.sapidus, mediante un estudio de diferentes fuentes bibliográficas e incorporando información de las personas que rodean su hábitat y en consecuencia más les afecta su presencia como son los arroceros, pescadores y personal especializado en especies invasoras. De esa manera conocer mejor que impactos puede contener este cangrejo, así como tener conocimiento de si la gente está concienciada de los problemas que puede suponer en el ecosistema. Una vez comprendamos la situación de la especie, estudiaremos si es necesaria una actuación o no contra esta especie, y si es así, estudiar qué actuación sería la mejor para su erradicación, control o gestión, basándonos en la información obtenida y las entrevistas, incluyendo la posibilidad de comercialización a gran escala sin límite de tallas, para su gestión., In this study, data and information about the American blue crab are understood, as well as its influence and invasive character that are currently perceiving the coasts of the Mediterranean. The main objective of this document is to understand the behavior of the species C. sapidus, by means of a study of different bibliographical sources and incorporating information of the people that surround their habitat and as a consequence they are more affected by their presence such as rice farmers, fishermen and staff specialized in invasive species. In this way, to know better what impacts this crab may contain, as well as to have knowledge of if people are aware of the problems that may arise in the ecosystem. Once we understand the situation of the species, we will study if an action is necessary or not against this species, and if so, study what action would be the best for its eradication, control or management, based on the information obtained and the interviews, including the possibility of commercialization on a large scale without size limit, for its management.

The early developmental stages of arthropods often vary and appear to be influenced by dietary conditions. It is hypothesized that food availability and dietary components may affect the number and length of developmental stages of the blue crab, Callinectes sapidus, specifically those that are reared in aquaculture settings. This hypothesis was examined with C. sapidus 1) larvae and 2) juveniles. 1) During the zoeal period, development from stage 1 to megalopae was monitored under a full factorial experiment with treatments: high and low prey density coupled with and without poly-β-hydroxybutyrate (PHB) supplementations. Our data showed that prey density influences variation in the zoeal development of C. sapidus by increasing stage skipping, reducing the number of the stages from 7-8 to 5-8. Additionally, a high prey density coupled with PHB supplementation caused increasing instances of stage skipping. 2) During the juvenile period, the growth was monitored for three molting events (57-165 days) under the following treatments: 0, 5, 10, and 20% chitin supplemented diets and squid control. Our data showed that chitin supplementation did not affect the growth of the juvenile C. sapidus (molt increment or interval).

El cangrejo azul, Callinectes sapidus Rathbun (1896), originario de las costas occidentales del Océano Atlántico, ha sido introducido en aguas mediterráneas donde actualmente se considera una especie invasora. Con el presente estudio se pretendió conocer la abundancia de C. sapidus, a través de las capturas en 3 puntos de muestreo del entorno costero de Gandia mediante trampas y a través de las capturas accidentales de la zona costera marina mediante redes. Aunque se debe tener precaución al interpretar estos resultados, dado el bajo número de capturas totales, las limitaciones conocidas de las trampas y que no todos los ejemplares capturados en el medio marino fueron entregados para este estudio; en el medio estuarino el porcentaje de machos capturados fue mayor que el de las hembras, a diferencia del medio marino, en el que ocurrió lo contrario. Estos hechos coinciden con la información biológica existente de dicha especie. El mayor conocimiento de la especie y la comercialización de C. sapidus podrían ser útiles para el posterior manejo de esta especie invasora., The blue crab, Callinectes sapidus Rathbun (1896), originally from the western shores of the Atlantic Ocean, has been introduced into Mediterranean waters where it is now considered an invasive species. The present study aimed to know the abundance of C. sapidus, through catches at 3 sampling points of the coastal environment of Gandia by means of traps and through the accidental catches of the marine coastal zone through nets. Although caution should be exercised in interpreting these results, given the low number of total catches, known limitations of the traps and that not all specimens caught in the marine environment were given for this study; in the estuarine environment the percentage of males captured was higher than that of females, unlike the marine environment, where the opposite occurred. These facts coincide with the existing biological information of this species. The greater knowledge of the species and the commercialization of C. sapidus could be useful for the later management of this invasive species.

El cangrejo azul, Callinectes sapidus Rathbun (1896), originario de las costas occidentales del Océano Atlántico, ha sido introducido en aguas mediterráneas donde actualmente se considera una especie invasora. Con el presente estudio se pretendió conocer la abundancia de C. sapidus, a través de las capturas en 3 puntos de muestreo del entorno costero de Gandia mediante trampas y a través de las capturas accidentales de la zona costera marina mediante redes. Aunque se debe tener precaución al interpretar estos resultados, dado el bajo número de capturas totales, las limitaciones conocidas de las trampas y que no todos los ejemplares capturados en el medio marino fueron entregados para este estudio; en el medio estuarino el porcentaje de machos capturados fue mayor que el de las hembras, a diferencia del medio marino, en el que ocurrió lo contrario. Estos hechos coinciden con la información biológica existente de dicha especie. El mayor conocimiento de la especie y la comercialización de C. sapidus podrían ser útiles para el posterior manejo de esta especie invasora., The blue crab, Callinectes sapidus Rathbun (1896), originally from the western shores of the Atlantic Ocean, has been introduced into Mediterranean waters where it is now considered an invasive species. The present study aimed to know the abundance of C. sapidus, through catches at 3 sampling points of the coastal environment of Gandia by means of traps and through the accidental catches of the marine coastal zone through nets. Although caution should be exercised in interpreting these results, given the low number of total catches, known limitations of the traps and that not all specimens caught in the marine environment were given for this study; in the estuarine environment the percentage of males captured was higher than that of females, unlike the marine environment, where the opposite occurred. These facts coincide with the existing biological information of this species. The greater knowledge of the species and the commercialization of C. sapidus could be useful for the later management of this invasive species.

El cangrejo azul, Callinectes sapidus Rathbun (1896), originario de las costas occidentales del Océano Atlántico, ha sido introducido en aguas mediterráneas donde actualmente se considera una especie invasora. Con el presente estudio se pretendió conocer la abundancia de C. sapidus, a través de las capturas en 3 puntos de muestreo del entorno costero de Gandia mediante trampas y a través de las capturas accidentales de la zona costera marina mediante redes. Aunque se debe tener precaución al interpretar estos resultados, dado el bajo número de capturas totales, las limitaciones conocidas de las trampas y que no todos los ejemplares capturados en el medio marino fueron entregados para este estudio; en el medio estuarino el porcentaje de machos capturados fue mayor que el de las hembras, a diferencia del medio marino, en el que ocurrió lo contrario. Estos hechos coinciden con la información biológica existente de dicha especie. El mayor conocimiento de la especie y la comercialización de C. sapidus podrían ser útiles para el posterior manejo de esta especie invasora., The blue crab, Callinectes sapidus Rathbun (1896), originally from the western shores of the Atlantic Ocean, has been introduced into Mediterranean waters where it is now considered an invasive species. The present study aimed to know the abundance of C. sapidus, through catches at 3 sampling points of the coastal environment of Gandia by means of traps and through the accidental catches of the marine coastal zone through nets. Although caution should be exercised in interpreting these results, given the low number of total catches, known limitations of the traps and that not all specimens caught in the marine environment were given for this study; in the estuarine environment the percentage of males captured was higher than that of females, unlike the marine environment, where the opposite occurred. These facts coincide with the existing biological information of this species. The greater knowledge of the species and the commercialization of C. sapidus could be useful for the later management of this invasive species.

El cangrejo azul, Callinectes sapidus Rathbun (1896), originario de las costas occidentales del Océano Atlántico, ha sido introducido en aguas mediterráneas donde actualmente se considera una especie invasora. Con el presente estudio se pretendió conocer la abundancia de C. sapidus, a través de las capturas en 3 puntos de muestreo del entorno costero de Gandia mediante trampas y a través de las capturas accidentales de la zona costera marina mediante redes. Aunque se debe tener precaución al interpretar estos resultados, dado el bajo número de capturas totales, las limitaciones conocidas de las trampas y que no todos los ejemplares capturados en el medio marino fueron entregados para este estudio; en el medio estuarino el porcentaje de machos capturados fue mayor que el de las hembras, a diferencia del medio marino, en el que ocurrió lo contrario. Estos hechos coinciden con la información biológica existente de dicha especie. El mayor conocimiento de la especie y la comercialización de C. sapidus podrían ser útiles para el posterior manejo de esta especie invasora., The blue crab, Callinectes sapidus Rathbun (1896), originally from the western shores of the Atlantic Ocean, has been introduced into Mediterranean waters where it is now considered an invasive species. The present study aimed to know the abundance of C. sapidus, through catches at 3 sampling points of the coastal environment of Gandia by means of traps and through the accidental catches of the marine coastal zone through nets. Although caution should be exercised in interpreting these results, given the low number of total catches, known limitations of the traps and that not all specimens caught in the marine environment were given for this study; in the estuarine environment the percentage of males captured was higher than that of females, unlike the marine environment, where the opposite occurred. These facts coincide with the existing biological information of this species. The greater knowledge of the species and the commercialization of C. sapidus could be useful for the later management of this invasive species.

El cangrejo azul, Callinectes sapidus Rathbun (1896), originario de las costas occidentales del Océano Atlántico, ha sido introducido en aguas mediterráneas donde actualmente se considera una especie invasora. Con el presente estudio se pretendió conocer la abundancia de C. sapidus, a través de las capturas en 3 puntos de muestreo del entorno costero de Gandia mediante trampas y a través de las capturas accidentales de la zona costera marina mediante redes. Aunque se debe tener precaución al interpretar estos resultados, dado el bajo número de capturas totales, las limitaciones conocidas de las trampas y que no todos los ejemplares capturados en el medio marino fueron entregados para este estudio; en el medio estuarino el porcentaje de machos capturados fue mayor que el de las hembras, a diferencia del medio marino, en el que ocurrió lo contrario. Estos hechos coinciden con la información biológica existente de dicha especie. El mayor conocimiento de la especie y la comercialización de C. sapidus podrían ser útiles para el posterior manejo de esta especie invasora., The blue crab, Callinectes sapidus Rathbun (1896), originally from the western shores of the Atlantic Ocean, has been introduced into Mediterranean waters where it is now considered an invasive species. The present study aimed to know the abundance of C. sapidus, through catches at 3 sampling points of the coastal environment of Gandia by means of traps and through the accidental catches of the marine coastal zone through nets. Although caution should be exercised in interpreting these results, given the low number of total catches, known limitations of the traps and that not all specimens caught in the marine environment were given for this study; in the estuarine environment the percentage of males captured was higher than that of females, unlike the marine environment, where the opposite occurred. These facts coincide with the existing biological information of this species. The greater knowledge of the species and the commercialization of C. sapidus could be useful for the later management of this invasive species.

The abundance of blue swimmer crabs, Portunus pelagicus throughout the Indo-West Pacific region makes it a valuable target species for fishery industry. The increasing demands of P. pelagicus have led to a growing interest on the broodstock selection of this particular crab species. This study examined the phylogenetic relationships, demographic history and population structure of P. pelagicus through sequence analyses of mitochondrial cytochrome c oxidase I (COI) gene (600 bp) as well as fragment analyses of four pairs of microsatellite loci. A total of 109 crab samples were collected from five different populations throughout the coastal areas of Malaysia. These include Perak (Pantai Remis and Kuala Sepetang), Johor (Pendas), Negeri Sembilan (Port Dickson), Terengganu (Besut) and Sarawak (Bako). In total, 15 haplotypes were obtained with 13 unique haplotypes and two shared haplotypes. The phylogenetic analyses via the Neighbour Joining (NJ), Maximum Parsimony (MP) and Maximum Likelihood (ML) methods supported the monophyletic status between P. pelagicus and P. sanguinolentus with high bootstrap value (100%). All three phylogenetic trees revealed similar tree topologies with differences in the bootstrap values. The clustering of all P. pelagicus samples into a single clade suggested that this species possibly belonged to a single species. The genetic identity of P. pelagicus was further elucidated with low genetic distances among the haplotypes (0.2-1.7%) via mitochondrial analyses. Limited variations were found among the populations of P. pelagicus with high haplotype diversity and low nucleotide diversity detected within each population. No hybrid individual was discovered based on the genetic analyses of P. pelagicus from sympatric sampling locations. Low FST values obtained among these populations also clarified that these crabs were compatible for breeding programs. One interesting finding of this study was the sharing of haplotypes between samples from Sarawa

The abundance of blue swimmer crabs, Portunus pelagicus throughout the Indo-West Pacific region makes it a valuable target species for fishery industry. The increasing demands of P. pelagicus have led to a growing interest on the broodstock selection of this particular crab species. This study examined the phylogenetic relationships, demographic history and population structure of P. pelagicus through sequence analyses of mitochondrial cytochrome c oxidase I (COI) gene (600 bp) as well as fragment analyses of four pairs of microsatellite loci. A total of 109 crab samples were collected from five different populations throughout the coastal areas of Malaysia. These include Perak (Pantai Remis and Kuala Sepetang), Johor (Pendas), Negeri Sembilan (Port Dickson), Terengganu (Besut) and Sarawak (Bako). In total, 15 haplotypes were obtained with 13 unique haplotypes and two shared haplotypes. The phylogenetic analyses via the Neighbour Joining (NJ), Maximum Parsimony (MP) and Maximum Likelihood (ML) methods supported the monophyletic status between P. pelagicus and P. sanguinolentus with high bootstrap value (100%). All three phylogenetic trees revealed similar tree topologies with differences in the bootstrap values. The clustering of all P. pelagicus samples into a single clade suggested that this species possibly belonged to a single species. The genetic identity of P. pelagicus was further elucidated with low genetic distances among the haplotypes (0.2-1.7%) via mitochondrial analyses. Limited variations were found among the populations of P. pelagicus with high haplotype diversity and low nucleotide diversity detected within each population. No hybrid individual was discovered based on the genetic analyses of P. pelagicus from sympatric sampling locations. Low FST values obtained among these populations also clarified that these crabs were compatible for breeding programs. One interesting finding of this study was the sharing of haplotypes between samples from Sarawa

Future climate scenarios predict an increase in temperature and dissolved carbon dioxide (pCO2) of the marine environment in the next century. Calcifying marine invertebrates are thought to be especially vulnerable to increases in pCO2 and although the effect of increasing temperature in many of these taxa is understood, less is known about the interactive effects of these stressors on the physiology of calcifying invertebrates. In the present study, juvenile blue crab (Callinectes sapidus) were exposed predicted future levels of temperature and pCO2 in a 2x2 factorial design for two complete molts (approximately 30 days). Increased temperature caused a significant increase in crab growth rate and food consumption, but at a cost to carapace thickness and chemistry. The carapaces of individuals exposed to increased temperature were significantly thinner and had significantly lower percent high-magnesium calcite (HMC), the mineral from which the carapace derives its strength. Although there was a significant increase in percent HMC in response to increased pCO2, this was paired with an increase in the concentration of magnesium, complicating the overall effect of increased pCO2 on the carapace. The temperature range tested in this study was not large enough to elicit a significant difference in mean oxygen consumption rate. Crabs were resilient to exposure to extremely high levels of pCO2; there was no significant effect of increased pCO2 on crab growth rate, food consumption, or oxygen consumption rate. Individual physiological response data were utilized in concert with historical and predicted water temperatures to determine effects of future predicted increases in water temperature on blue crab overwintering behavior in the Chesapeake Bay. Model data indicated a significant shortening of the overwintering period from approximately 3.5 months currently to between 1.5 and 3 months, depending on the climate model utilized for the predictions. Increases to growing sea

[ES] Two unusual crustacean decapods are reported for the first time from the coasts of Galicia (NW Spain). A specimen of caramote prawn Penaeus kerathurus (Penaeidae) was caught in the Ría de Arousa in 2014 and a specimen of blue crab Callinectes sapidus (Portunidae) was caught in the Ría de Vigo in 2015, the first one being a native species whereas the second is an exotic one. A tropicalization process due to ocean warming could favour the arrival of warm water species to temperate latitudes as well as the establishment of introduced species., [FR] Deux crustacés décapodes inhabituels sont signalés pour la première fois sur les côtes de Galice (Nord-ouest Espagne). Un spécimen de caramote Penaeus kerathurus (Penaeidae) a été capturé dans la Ria de Arousa en 2014 et un spécimen de crabe bleu Callinectes sapidus (Portunidae) a été capturé dans la Ria de Vigo en 2015, la première est considérée comme une espèce indigène alors que la seconde est considérée comme exotique. Le réchauffement de l’océan provoquant un processus de tropicalisation pourrait favoriser l’arrivée d’espèces d’eaux chaudes à des latitudes tempérées ainsi que l’établissement d’espèces introduites.

In Maryland, commercial blue crab (Callinectes sapidus) harvests are monitored through mandatory, annual harvest reporting, but no monitoring exists for recreational fishers. This study used a large-scale mark-recapture program to assess relative exploitation between the recreational and commercial fishing sectors in 15 harvest reporting areas of Maryland, then incorporated movement information and extrapolated reported commercial harvest data to generate statewide estimates of recreational harvest. Results indicate spatial variation in recreational fishing, with a majority of recreational harvests coming from tributaries of the Western Shore and the Wye and Miles Rivers on the Eastern Shore. Statewide, recreational harvest has remained 8% as large as commercial harvest despite management changes in 2008, and remains a larger proportion (12.8%) of male commercial harvest. In addition, this study provides detailed spatial information on recreational harvest and the first information on rates of exchange of male crabs among harvest reporting areas.

The evaluation and identification of habitats that function as nurseries for marine species has the potential to improve conservation and management. A key assessment of nursery habitat is estimating individual growth. However, the discrete growth of crustaceans presents a challenge for many traditional in situ techniques to accurately estimate growth over a short temporal scale. To evaluate the use of nucleic acid ratios (R:D) for juvenile blue crab (Callinectes sapidus), I developed and validated an R:D-based index of growth in the laboratory. R:D based growth estimates of crabs collected in the Patuxent River, MD indicated growth ranged from 0.8-25.9 (mg·g-1·d-1). Overall, there was no effect of size on growth, whereas there was a weak, but significant effect of date. These data provide insight into patterns of habitat-specific growth. These results highlight the complexity of the biological and physical factors which regulate growth of juvenile blue crabs in the field.

Callinectes sapidus reo-like virus (RLV) is a fatal to blue crabs and consistently found within the Chesapeake Bay. Development of a sensitive and reliable RT-qPCR assay permitted a precise assessment of RLV prevalence in crabs captured from locations near and far from soft-shell crab production sites. Viral prevalence was temporally and spatially highly variable, but outbreaks of RLV appeared to be localized to an area of 1 - 2 km2. When significantly different between sites, higher prevalence was observed near soft-shell crab production. RLV prevalence was not correlated with crab characteristics, with the exception of larger mean carapace width for infected crabs. Sequences of RLV PCR products were used to compare genotypes of outbreak and non-outbreak infections. Identical genotypes were found in outbreaks from the middle Chesapeake Bay and Long Island, NY. Together, the prevalence and genetic data are consistent with RLV outbreaks being caused by focal spread of the virus through a local population.