Pesca y Acuicultura. Serie Recursos Pesqueros-Junta de Andalucía, 2007
-[Fishing for bivalves in the ocean coastline of the Southwest coast of the Iberian Peninsula: fi... more -[Fishing for bivalves in the ocean coastline of the Southwest coast of the Iberian Peninsula: fishing grounds and equipment description, management measures, biology of the commercial species and bivalve species catalogue] by Gaspar, MB; Moreno, O.; Díaz, A.; Manzano, C.(eds.); Pereira, A.; Palanco, I.; Rufino, M.(2007) in Spanish
Pesca y Acuicultura. Serie Recursos Pesqueros-Junta de Andalucía, 2007
-[Fishing for bivalves in the ocean coastline of the Southwest coast of the Iberian Peninsula: fi... more -[Fishing for bivalves in the ocean coastline of the Southwest coast of the Iberian Peninsula: fishing grounds and equipment description, management measures, biology of the commercial species and bivalve species catalogue] by Gaspar, MB; Moreno, O.; Díaz, A.; Manzano, C.(eds.); Pereira, A.; Palanco, I.; Rufino, M.(2007) in Spanish
... Os transmissores rádio-acústicos são utilizados em ambientes dulce-aquícolas, possuem uma ant... more ... Os transmissores rádio-acústicos são utilizados em ambientes dulce-aquícolas, possuem uma antena ... Diplodus sargus O sargo, Diplodus sargus (Linnaeus, 1758), encontra-se no Atlântico Este, desde o Golfo da Biscaia até à África do Sul, incluindo o Mediterrâneo eo ...
ABSTRACT Marine protected areas (MPAs) are today’s most important tools for the spatial managemen... more ABSTRACT Marine protected areas (MPAs) are today’s most important tools for the spatial management and conservation of marine species. Yet, the true protection that they provide to individual fish is unknown, leading to uncertainty associated with MPA effectiveness. In this study, conducted in a recently established coastal MPA in Portugal, we combined the results of individual home range estimation and population distribution models for 3 species of commercial importance and contrasting life histories to infer (1) the size of suitable areas where they would be fully protected and (2) the vulnerability to fishing mortality of each species. Results show that the relationship between MPA size and effective protection is strongly modulated by both the species’ home range and the distribution of suitable habitat inside and outside the MPA. This approach provides a better insight into the true potential of MPAs in effectively protecting marine species, since it can reveal the size and location of the areas where protection is most effective and a clear, quantitative estimation of the vulnerability to fishing throughout an entire MPA.
ABSTRACT Artificial reefs are used as management tools for coastal fisheries and ecosystems and t... more ABSTRACT Artificial reefs are used as management tools for coastal fisheries and ecosystems and the knowledge of habitat use and fish movements around them is necessary to understand their performance and improve their design and location. In this study wild specimens of Diplodus sargus were tagged with acoustic tags and their movements were tracked using passive acoustic telemetry. The monitored area enclosed a natural rocky reef, an adjacent artificial reef (AR) and shallower sandy bottoms. Most of the fish were close to full time residents in the monitored area. Results revealed that D. sargus use the natural reef areas on a more frequent basis than the AR. However, excursions to the adjacent AR and sandy bottoms were frequently detected, essentially during daytime. The use of acoustic telemetry allowed a better understanding of the use of artificial reef structures and its adjacent areas by wild D. sargus providing information that is helpful towards the improvement of AR design and location.
Acoustic telemetry and standard tag-recapture were used to determine the home range and residency... more Acoustic telemetry and standard tag-recapture were used to determine the home range and residency of juveniles and sub-adults of Diplodus sargus and Diplodus vulgaris in the Ria Formosa (Portugal) coastal lagoon. Maximum time between recaptures for the standard tag-recapture method was 128 days for D. sargus and 30 days for D. vulgaris. The majority of the fish were recaptured in the vicinity of the tagging location. Fish tagged with acoustic transmitters had a maximum period of time between first and last detections of 62 days for D. sargus and 260 days for D. vulgaris. Minimum convex polygons areas ranged between 148 024 m2 and 525 930 m2 for D. sargus and between 23 786 m2 and 42 134 m2 for D. vulgaris. Both species presented a high residency index between first and last detections. Two D. sargus tagged with acoustic tags were recaptured by fishermen outside the coastal lagoon at distances of 12 km and 90 km from the tagging position, providing evidence that this species leaves the Ria Formosa during the winter time for the adjacent coastal waters. The results of this study reinforce the importance of Ria Formosa as a nursery for D. sargus and D. vulgaris in the south coast of Portugal.
Pesca y Acuicultura. Serie Recursos Pesqueros-Junta de Andalucía, 2007
-[Fishing for bivalves in the ocean coastline of the Southwest coast of the Iberian Peninsula: fi... more -[Fishing for bivalves in the ocean coastline of the Southwest coast of the Iberian Peninsula: fishing grounds and equipment description, management measures, biology of the commercial species and bivalve species catalogue] by Gaspar, MB; Moreno, O.; Díaz, A.; Manzano, C.(eds.); Pereira, A.; Palanco, I.; Rufino, M.(2007) in Spanish
Pesca y Acuicultura. Serie Recursos Pesqueros-Junta de Andalucía, 2007
-[Fishing for bivalves in the ocean coastline of the Southwest coast of the Iberian Peninsula: fi... more -[Fishing for bivalves in the ocean coastline of the Southwest coast of the Iberian Peninsula: fishing grounds and equipment description, management measures, biology of the commercial species and bivalve species catalogue] by Gaspar, MB; Moreno, O.; Díaz, A.; Manzano, C.(eds.); Pereira, A.; Palanco, I.; Rufino, M.(2007) in Spanish
... Os transmissores rádio-acústicos são utilizados em ambientes dulce-aquícolas, possuem uma ant... more ... Os transmissores rádio-acústicos são utilizados em ambientes dulce-aquícolas, possuem uma antena ... Diplodus sargus O sargo, Diplodus sargus (Linnaeus, 1758), encontra-se no Atlântico Este, desde o Golfo da Biscaia até à África do Sul, incluindo o Mediterrâneo eo ...
ABSTRACT Marine protected areas (MPAs) are today’s most important tools for the spatial managemen... more ABSTRACT Marine protected areas (MPAs) are today’s most important tools for the spatial management and conservation of marine species. Yet, the true protection that they provide to individual fish is unknown, leading to uncertainty associated with MPA effectiveness. In this study, conducted in a recently established coastal MPA in Portugal, we combined the results of individual home range estimation and population distribution models for 3 species of commercial importance and contrasting life histories to infer (1) the size of suitable areas where they would be fully protected and (2) the vulnerability to fishing mortality of each species. Results show that the relationship between MPA size and effective protection is strongly modulated by both the species’ home range and the distribution of suitable habitat inside and outside the MPA. This approach provides a better insight into the true potential of MPAs in effectively protecting marine species, since it can reveal the size and location of the areas where protection is most effective and a clear, quantitative estimation of the vulnerability to fishing throughout an entire MPA.
ABSTRACT Artificial reefs are used as management tools for coastal fisheries and ecosystems and t... more ABSTRACT Artificial reefs are used as management tools for coastal fisheries and ecosystems and the knowledge of habitat use and fish movements around them is necessary to understand their performance and improve their design and location. In this study wild specimens of Diplodus sargus were tagged with acoustic tags and their movements were tracked using passive acoustic telemetry. The monitored area enclosed a natural rocky reef, an adjacent artificial reef (AR) and shallower sandy bottoms. Most of the fish were close to full time residents in the monitored area. Results revealed that D. sargus use the natural reef areas on a more frequent basis than the AR. However, excursions to the adjacent AR and sandy bottoms were frequently detected, essentially during daytime. The use of acoustic telemetry allowed a better understanding of the use of artificial reef structures and its adjacent areas by wild D. sargus providing information that is helpful towards the improvement of AR design and location.
Acoustic telemetry and standard tag-recapture were used to determine the home range and residency... more Acoustic telemetry and standard tag-recapture were used to determine the home range and residency of juveniles and sub-adults of Diplodus sargus and Diplodus vulgaris in the Ria Formosa (Portugal) coastal lagoon. Maximum time between recaptures for the standard tag-recapture method was 128 days for D. sargus and 30 days for D. vulgaris. The majority of the fish were recaptured in the vicinity of the tagging location. Fish tagged with acoustic transmitters had a maximum period of time between first and last detections of 62 days for D. sargus and 260 days for D. vulgaris. Minimum convex polygons areas ranged between 148 024 m2 and 525 930 m2 for D. sargus and between 23 786 m2 and 42 134 m2 for D. vulgaris. Both species presented a high residency index between first and last detections. Two D. sargus tagged with acoustic tags were recaptured by fishermen outside the coastal lagoon at distances of 12 km and 90 km from the tagging position, providing evidence that this species leaves the Ria Formosa during the winter time for the adjacent coastal waters. The results of this study reinforce the importance of Ria Formosa as a nursery for D. sargus and D. vulgaris in the south coast of Portugal.
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