Association of European Marine Biological Laboratories

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Organizational Unit

Publications

Response of kelps from different latitudes to consecutive heat shock

Publication . Pereira, Tania R.; Engelen, Aschwin H.; Pearson, Gareth; Valero, Myriam; Serrao, Ester A.

Although extensive work has focused on kelp responses to constant temperature, little is known about their response to the consecutive temperature shocks they are often exposed to in the shallow subtidal and intertidal pools. Here we characterized the responses of the two southernmost forest-forming kelp species in the Northeast Atlantic, Laminaria ochroleuca De La Pylaie and Saccorhiza polyschides (Lightf.) Batt. to multiple cycles of thermal stress. Individuals from the upper vertical limit of the geographical distribution edges where the two species co-occur forming forests, France and Portugal, were exposed to 4 consecutive cycles of thermal shock simulating a spring tide. A 24 h cycle consisted of culture at 15 degrees C, plus 1 h heat shock at one of five levels (20, 22.5, 25, 27.5 or 30 degrees C). The maximum quantum yield (Fv/Fm) of chlorophyll fluorescence of photosystem 2 (PS2) was used to detect impaired reaction center function, as a proxy for individual fitness costs, during recovery from heat shock. Both species showed resilience to temperatures from 20 to 25 degrees C. While exposure to 27.5 degrees C caused no inhibition to Fv/Fm of S. polyschides, a threshold was met above this temperature and exposure to 30 degrees C caused the death of all individuals. In contrast, L ochroleuca from France was damaged but able to survive 30 degrees C shocks and individuals from Portugal showed complete resilience to this treatment. In both species, blade elongation decreased with increasing temperature, with necrosis surpassing growth at higher temperatures. Resilience to high temperature exposure may confer an advantage to L ochroleuca to colonize intertidal pools on the Portuguese coast, in agreement with the observation that both species recruit in tide pools but only L ochroleuca reach adulthood. Our results indicate that as summer temperatures increase with climate change, the disappearance of S. polyschides from intertidal pools and a decrease in the density of L ochroleuca can be expected. (C) 2014 Elsevier B.V. All rights reserved.

2015-02Journal article

Open Access

Preliminary results on the daily and seasonal rhythms of cuttlefish Sepia officinalis (Linnaeus, 1758) locomotor activity in captivity

Publication . Oliveira, Catarina; Grano-Maldonado, Mayra; Gonçalves, Rui A.; Frias, Paulo; Sykes, António V.

Cephalopods are considered as an alternate group for aquaculture species diversification [1,2], not only because they are a good food source (highly appreciated in some worldwide markets, e.g., Portugal, Spain, Italy and Asia) and have the potential to quickly reach a market size, but also because they are considered animal models in several fields of research [3–5], and it is expected that such models are progressively obtained from bioteriums instead of being captured from nature. Despite the recent advances in culture protocols of several cephalopod species [2], there is still little information available about the biological rhythms of cephalopods in captivity. In fact, to the best of our knowledge, there are only 4 published papers concerning this theme, and these are focused on octopus species [6–9]. This issue assumes increasing importance with the enforcement of EU welfare legislation (Directive 2010/63/EU), and this information is critical for the future update of Annex III (housing conditions) for cephalopods of that Directive, and for a future update of the Guidelines for the Care and Welfare of Cephalopods in Research [10]. If it is considered that the European cuttlefish Sepia officinalis (Linnaeus, 1758) may have, at the least, two different sleep‐like states [11], the importance of this study becomes even more evident.

2017Journal article

Open Access

The use of different anaesthetics as welfare promoters during short-term human manipulation of European cuttlefish (Sepia officinalis) juveniles

Publication . Gonçalves, Rui A.; Aragão, C.; Frias, P. A.; Sykes, António V.

Anaesthetics are frequently used to prevent injuries, stress and to promote welfare while handling animals. The efﬁciency of ﬁve anaesthetics for short-term handling of the European cuttleﬁsh (Sepia ofﬁcinalis) was tested in order to determine the best agent and its concentration. Ethanol (10.0, 20.0 and 30.0 mL.L−1 ), clove oil (0.05, 0.15 mL.L−1 ), hypothermia (8 °C), magnesium chloride (hexahydrated; 20.0, 27.0 g.L−1 ) and AQUI-S® (10.9 μl.L−1 ) were the selected anaesthetics. This choice was preceded by a preliminary trial, with additional agents, where 2-phenoxyethanol (10, 15, 20, 30 mL.L−1 ) and MS-222® (30, 40 mg.L−1 ) were used.

2012Journal article

Restricted

Resistance of seagrass habitats to ocean acidification via altered interactions in a tri-trophic chain

Publication . Martínez-Crego, Begoña; Vizzini, Salvatrice; Califano, Gianmaria; Massa-Gallucci, Alexia; Andolina, Cristina; Gambi, Maria Cristina; Santos, Rui

Despite the wide knowledge about prevalent effects of ocean acidification on single species, the consequences on species interactions that may promote or prevent habitat shifts are still poorly understood. Using natural CO2 vents, we investigated changes in a key tri-trophic chain embedded within all its natural complexity in seagrass systems. We found that seagrass habitats remain stable at vents despite the changes in their tri-trophic components. Under high pCO2, the feeding of a key herbivore (sea urchin) on a less palatable seagrass and its associated epiphytes decreased, whereas the feeding on higher-palatable green algae increased. We also observed a doubled density of a predatory wrasse under acidified conditions. Bottom-up CO2 effects interact with top-down control by predators to maintain the abundance of sea urchin populations under ambient and acidified conditions. The weakened urchin herbivory on a seagrass that was subjected to an intense fish herbivory at vents compensates the overall herbivory pressure on the habitat-forming seagrass. Overall plasticity of the studied system components may contribute to prevent habitat loss and to stabilize the system under acidified conditions. Thus, preserving the network of species interactions in seagrass ecosystems may help to minimize the impacts of ocean acidification in near-future oceans.

2020Journal article

Open Access

The effects of rearing temperature on reproductive conditioning of stalked barnacles (Pollicipes pollicipes)

Publication . Franco, Sofia C.; Aldred, Nick; Sykes, António V.; Cruz, Teresa; Clare, Anthony S.

Pollicipes pollicipes (Crustacea; Pedunculata) is a delicacy on the Iberian Peninsula where, in recent years, stock shortages associated with high market value have increased interest in the aquaculture potencial of this species. Though broodstock has been maintained in captivity, detailed culture conditions are lacking.

2015Journal article

Restricted