Browsing by Author "Silva, Alexandra"
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- EXPERIÊNCIA PILOTO PARA AVALIAR A SOBREVIVÊNCIA DA CAVALA (Scomber colias) PÓS-SLIPPING NA PESCA DO CERCOPublication . Dias, Inês C.; Feijó, Diana; Marçalo, Ana; Guerreiro, Pedro M.; Nogueira, Marta; Bandarra, Cidália; Silva, Alexandra; Instituto Português do Mar e da Atmosfera, I.P.Under the scope of Sardinha2020 Project, a pilot experiment was carried out to study the survival rate of chub mackerel (Scomber colias) after slipping. Slipping is the release of unwanted capture in purse seining, by lowering the head rope of the net and rolling over the fish back into the water. In Southwestern Portugal (Sesimbra), during the summer of 2020, the experiment was carried out using 2 small net pens (control and slipping treatment) moored in the open ocean, where fish slipped by a purse-seiner were monitored daily to evaluate the survival rate of chub mackerel. The control pen contained fish slipped in the initial moments of slipping (less crowding and density), and the slipping treatment contained fish aggregated at high densites towards the end of the operation. The results of this experiment revealed a high survival rate of chub mackerel on both net pens, reaching 94% in the slipping treatment and 97.7% in the control, after a 5 day trial period. For horse mackerel (Trachurus trachurus), unintentionally introduced inside the nets, this study revealed a reduced survival rate of 40% in the slipping treatment compared to 85% in the control net, suggesting that the slipping activity for this species could induce high motalities. In this study, individuals’ condition factor and caudal indexes, as well as physical conditions were evaluated during the experiment. It was verified that, for both species and for both control and slipping treatment, dead individuals, in general, presented more deterioration of these conditions, compared to the survivors. This work aims to evaluate the survival rate of chub mackerel and horse mackerel after purse seine slipping. This work is novel for both species, thus we expect this new knowledge, will be an important contribution to improve stock assessment of these species.
- EXPERIÊNCIA PILOTO PARA AVALIAR A SOBREVIVÊNCIA DA CAVALA (Scomber colias) PÓS-SLIPPING NA PESCA DO CERCOPublication . Bandarra, Cidália; Silva, Alexandra; Instituto Português do Mar e da Atmosfera, I.P.Under the scope of Sardinha2020 Project, a pilot experiment was carried out to study the survival rate of chub mackerel (Scomber colias) after slipping. Slipping is the release of unwanted capture in purse seining, by lowering the head rope of the net and rolling over the fish back into the water. In Southwestern Portugal (Sesimbra), during the summer of 2020, the experiment was carried out using 2 small net pens (control and slipping treatment) moored in the open ocean, where fish slipped by a purse-seiner were monitored daily to evaluate the survival rate of chub mackerel. The control pen contained fish slipped in the initial moments of slipping (less crowding and density), and the slipping treatment contained fish aggregated at high densites towards the end of the operation. The results of this experiment revealed a high survival rate of chub mackerel on both net pens, reaching 94% in the slipping treatment and 97.7% in the control, after a 5 day trial period. For horse mackerel (Trachurus trachurus), unintentionally introduced inside the nets, this study revealed a reduced survival rate of 40% in the slipping treatment compared to 85% in the control net, suggesting that the slipping activity for this species could induce high motalities. In this study, individuals’ condition factor and caudal indexes, as well as physical conditions were evaluated during the experiment. It was verified that, for both species and for both control and slipping treatment, dead individuals, in general, presented more deterioration ofthese conditions, compared to the survivors. This work aims to evaluate the survival rate of chub mackerel and horse mackerel after purse seine slipping. This work is novel for both species, thus we expect this new knowledge, will be an important contribution to improve stock assessment of these species.
- FROTA COSTEIRA DE CERCO CARACTERIZAÇÃO TECNOLÓGICA E TIPOLOGIAS DE EMBARCAÇÕESPublication . Parente, Joaquim; Feijó, Diana; Silva, Alexandra; Instituto Português do Mar e da Atmosfera, I.P.It is intended to characterize coastal seine vessels with an active license in 2016, operating in ICES zone 9a, depending on the shape of the hull and structures on the deck, as well as on the type of equipment used for hauling and handling the seine gear on board. The grouping of vessels into typologies will depend on that characterization and on the degree of modernization of the vessels. Most vessels have a high degree of modernization of the deck, promoting the speed of fishing operations and improving the quality and safety of work on board. Currently, there are few vessels operating without a purse line reel or that do not have at least one crane to facilitate the handling of cargo and aid in fishing maneuvers, which was very infrequent to observe 15 years ago. The placement of a gantry on the stern deck, aims to facilitate maneuvers with the seine skiff and to improve the working conditions and safety of the crew, being more common in larger vessels due to the larger spaces on deck. Five typologies were identified in the current composition of the coastal seine fleet operating off the Portuguese mainland coast, each one presenting different degrees of modernization. The greater the size of the vessel, the greater will be the deck space available for the deployment of structures and fishing equipment that increase both the vessel's fishing power and the comfort and safety of the crew on board.
- The relationship between childhood abuse and adult attachment styles: the mediator role of sensory over-responsivityPublication . Silva, Alexandra; Rocha, Nuno; Pinto, ÉliaAbusive experiences in childhood are common and can have effects on health and well-being that can last for many years, including altering the interpersonal behavior. There is also evidence showing that these early negative experiences may cause alteration in sensory modulation. This study aimed to understand if sensory over-responsivity (SOR) may play an important role in mediating the association between childhood abuse (Emotional Abuse, Emotional Neglect, Sexual Abuse, Physical Abuse, Physical Neglect) and Attachment-related Anxiety and Avoidance in adult romantic relationships. The sample consisted of 500 individuals aged 18-62 years (M= 28.83, SD = 7.82). Participants in this study completed an online survey, which contained the following instruments: Sensory Processing Scale Inventory (SPSI), Childhood Trauma Questionnaire (CTQ-SF), and Experiences in Close Relationships Questionnaire (ECR). The proposed mediation models have a higher mediation percentage for attachment-related anxiety rather than avoidance. All variables predicted the mediator, except sexual abuse that predicts the outcome but did not predict the overall model when the mediator was included.
- The relationship between childhood abuse and adult attachment styles: the mediator role of sensory over-responsivityPublication . Silva, Alexandra; Ferreira, Simão; Silva Pinto, Élia; Rocha, Susana Aguiar; Barbosa-Rocha, NunoChild abuse portrays health and well-being issues that can last for several years, including altering interpersonal behavior. Evidence has shown that these early negative experiences may cause changes in sensory modulation. This study aimed to understand if sensory over-responsivity (SOR) plays an important role in mediating the association between childhood abuse (emotional abuse, emotional neglect, sexual abuse, physical abuse, physical neglect) and attachment-related anxiety or avoidance in adult romantic relationships. An online survey was conducted to exam ine these associations in a Portuguese community sample (N = 500) aged 18–62 years. The presented mediation models shown a higher mediation percentage for attachment-related anxiety rather than avoidance. All variables predicted the mediator, except sexual abuse which did not predict the overall model when the mediator was included. Our results have implications for individual treatment approaches regarding child abuse victims and can certainly influence intervention strategies.