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Although recruitment patterns of Pollicipes pollicipes (Crustacea: Scalpelliformes) in the wild have been investigated, no studies have yet focused on the factors that affect settlement. In the present paper, settlement of P. pollicipes on conspecifics (gregarious settlement) was investigated in the laboratory as a function of environmental conditions (hydrodynamics, temperature, light and salinity), larval age and batch. This study aimed to understand how these factors modulate settlement in the laboratory and elucidate how they might impact recruitment patterns in nature. Maximum attachment on adults was 30-35%, with a one-week metamorphosis rate of 70-80%. Batch differences affected both attachment and metamorphosis. Attachment rate was higher at natural salinity (30-40 psu), with lower salinity (20 psu) decreasing metamorphosis rate. Cyprid attachment was stimulated by light conditions and circulating water. This might relate to a preference for positioning high in the water column in nature, but also to increased cyprid-surface contact in conditions of circulating water. Older cyprids (3 or 6 days) showed higher attachment than un-aged larvae, though fewer 6-day-old larvae metamorphosed. Temperature did not affect attachment rate, but the metamorphosis rate decreased at 14°C (compared with 17 or 20°C), implying that differences in temperature during the breeding season can affect how quickly cyprids metamorphose to the juvenile. Cyprids survived for prolonged periods ( ≥ 20 days; 40% survival), likely due to efficient energy saving by intercalating long periods of inactivity with fast bursts of activity upon stimulation. Aunque se han investigado los patrones de reclutamiento de Pollicipes pollicipes (Crustacea: Scalpelliformes) en la naturaleza, actualmente no existen estudios sobre los factores que afectan al asentamiento larval. En el presente trabajo, el asentamiento de larvas de P. pollicipes sobre adultos conspecíficos (asentamiento gregario) fue investigado en el laboratorio en función de las variables ambientales (hidrodinamismo, temperatura, luz y salinidad), la edad y los distintos lotes de larvas. Este estudio tuvo como objetivo comprender cómo estos factores afectaban al asentamiento en el laboratorio y elucidar el modo en que podrían afectar a los patrones de reclutamiento en el medio natural. La fijación máxima en adultos fue de 30-35%, con una tasa de metamorfosis de 70 a 80% en una semana. Las tasas de fijación y de metamorfosis variaron dependiendo de los distintos lotes de larvas. La tasa de fijación fue superior cuando la salinidad era la natural (30-40 psu), mientras que la tasa de metamorfosis disminuía cuando la salinidad era inferior (20 psu). La fijación de la larva cipris se estimulaba en condiciones de luz y agua circulante, lo que puede estar relacionado con la preferencia por el posicionamiento de la larva cipris en lo alto de la columna de agua en el medio natural, y además, también con un mayor contacto entre la larva cipris con las superficies en condiciones de agua circulante. Las larvas cipris de más edad (de 3 a 6 días) tuvieron una fijación más alta que las de menor edad, aunque luego, menos larvas de 6 días de edad metamorfosearan. La temperatura no afectó a la tasa de fijación, pero sí se reducía la tasa de metamorfosis a 14°C (en comparación con 17 o 20°C), lo que implica que las diferencias en la temperatura durante el período de reproducción pueden afectar a la rapidez de la metamorfosis de las larvas cipris a juveniles. Las larvas cipris sobrevivieron periodos de tiempo prolongados ( ≥ 20 días; con un 40% de supervivencia), probablemente debido a una capacidad de conservación de energía eficiente, intercalando largos períodos de inactividad con movimientos repentinos y actividad cuando eran estimuladas.

Although recruitment patterns of Pollicipes pollicipes (Crustacea: Scalpelliformes) in the wild have been investigated, no studies have yet focused on the factors that affect settlement. In the present paper, settlement of P. pollicipes on conspecifics (gregarious settlement) was investigated in the laboratory as a function of environmental conditions (hydrodynamics, temperature, light and salinity), larval age and batch. This study aimed to understand how these factors modulate settlement in the laboratory and elucidate how they might impact recruitment patterns in nature. Maximum attachment on adults was 30-35%, with a one-week metamorphosis rate of 70-80%. Batch differences affected both attachment and metamorphosis. Attachment rate was higher at natural salinity (30-40 psu), with lower salinity (20 psu) decreasing metamorphosis rate. Cyprid attachment was stimulated by light conditions and circulating water. This might relate to a preference for positioning high in the water column in nature, but also to increased cyprid-surface contact in conditions of circulating water. Older cyprids (3 or 6 days) showed higher attachment than un-aged larvae, though fewer 6-day-old larvae metamorphosed. Temperature did not affect attachment rate, but the metamorphosis rate decreased at 14°C (compared with 17 or 20°C), implying that differences in temperature during the breeding season can affect how quickly cyprids metamorphose to the juvenile. Cyprids survived for prolonged periods ( ≥ 20 days; 40% survival), likely due to efficient energy saving by intercalating long periods of inactivity with fast bursts of activity upon stimulation., Aunque se han investigado los patrones de reclutamiento de Pollicipes pollicipes (Crustacea: Scalpelliformes) en la naturaleza, actualmente no existen estudios sobre los factores que afectan al asentamiento larval. En el presente trabajo, el asentamiento de larvas de P. pollicipes sobre adultos conspecíficos (asentamiento gregario) fue investigado en el laboratorio en función de las variables ambientales (hidrodinamismo, temperatura, luz y salinidad), la edad y los distintos lotes de larvas. Este estudio tuvo como objetivo comprender cómo estos factores afectaban al asentamiento en el laboratorio y elucidar el modo en que podrían afectar a los patrones de reclutamiento en el medio natural. La fijación máxima en adultos fue de 30-35%, con una tasa de metamorfosis de 70 a 80% en una semana. Las tasas de fijación y de metamorfosis variaron dependiendo de los distintos lotes de larvas. La tasa de fijación fue superior cuando la salinidad era la natural (30-40 psu), mientras que la tasa de metamorfosis disminuía cuando la salinidad era inferior (20 psu). La fijación de la larva cipris se estimulaba en condiciones de luz y agua circulante, lo que puede estar relacionado con la preferencia por el posicionamiento de la larva cipris en lo alto de la columna de agua en el medio natural, y además, también con un mayor contacto entre la larva cipris con las superficies en condiciones de agua circulante. Las larvas cipris de más edad (de 3 a 6 días) tuvieron una fijación más alta que las de menor edad, aunque luego, menos larvas de 6 días de edad metamorfosearan. La temperatura no afectó a la tasa de fijación, pero sí se reducía la tasa de metamorfosis a 14°C (en comparación con 17 o 20°C), lo que implica que las diferencias en la temperatura durante el período de reproducción pueden afectar a la rapidez de la metamorfosis de las larvas cipris a juveniles. Las larvas cipris sobrevivieron periodos de tiempo prolongados ( ≥ 20 días; con un 40% de supervivencia), probablemente debido a una capacidad de conservación de energía eficiente, intercalando largos períodos de inactividad con movimientos repentinos y actividad cuando eran estimuladas.

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Aquaculture is expanding quickly worldwide and provides more than half of the seafood production, introducing a range of potentially controversial issues, which may impact public perceptions. UK aquaculture is one of the largest EU producers by volume and value, with farmed fish and shellfish sub-sectors having very different production basis, representation, socio-economic standing and visibility across the UK. Increasing the acceptability of aquaculture, both in terms of its products and production process, evidenced by positive consumer behaviour and effective social licence to operate, is essential to enable the sustained growth of aquaculture. Similarly, improving consumer and citizen awareness and engagement with aquaculture production can constitute an important tool to motivate the transition to more sustainable production practices and higher transparency within the supply chain. However, building this approval, awareness and meaningful engagement requires an understanding of the perceptions and attitudes to aquaculture, so that effective communication and engagement strategies can be developed. The goal of this study is to enable such a transition. Accordingly, the study has been divided in two parts. Firstly, a critical literature review of consumers’ perceptions/attitudes towards aquaculture and acceptance of seafood products. Secondly, a qualitative focus group study on the perception and attitudes of UK consumers and communities towards fish and shellfish aquaculture and their products. The findings showed that there is a lack of knowledge of all participants about fish and shellfish farming, however the community mixed-consumers group (CMC) had a clearer vision of what these practices consist of, given their proximity to them. Regarding risks and benefits of aquaculture, the non-consumers (NC) emphasized a lot more the main risks of these practices, them being fish welfare and environmental impacts, likely due to this groups’ ethical beliefs. CMC group highlighted the fact that wild fish are of higher quality, being fresher and tastier, and confirming again the socio-demographic effects on consumer behaviour. Wild fish was perceived as the best regarding health and safety, which emphasizes the importance for the fish farming sector to communicate the benefits of farmed fish. The main reason for this gap between consumer perception and evidence seems to be the lack of consumer knowledge concerning aquaculture, resulting in the use of emotions to judge farmed fish and its "industrial" production process as less positive than the "natural" wild fish. Nevertheless, farmed fish has two major advantages compared to wild fish, which are more availability and lower price. The findings of this study also revealed that a more conscious choice is dependent on each person's financial standing. The future of aquaculture depends on consumer’s and citizen’s acceptance of the industry and effective social licence to operate. Studies like this one are fundamental to understand the factors that affect people's perception of aquaculture and its products. It is essential to consider potential marketing strategies designed to enhance awareness and facilitate communication about the aquaculture and its products. Therefore, a marketing strategy aiming to increase public awareness could improve the value of the product, improving the image of aquaculture products and increasing consumer preferences for farmed fish.