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- An overview of jellyfish aquaculture: for food, feed, pharma and funPublication . Duarte, Inês Matos; Marques, Sónia Cotrim; Leandro, Sérgio Miguel; Calado, RicardoInterest on jellyfish research has significantly increased over the last two decades, mostly driven by the potential benefits of their high-end uses. Recent efforts have been put forward towards the commercial use of scyphozoan jellyfish, although the pipeline leading to their full exploitation is still at an early stage of development. Indeed, further research and several technical advances are still required to expand the use of these bioresources to a larger and more sustainable scale. Here, we describe the state of the art of culture systems already available to farm these organisms throughout the different stages of their life cycle and provide an overview of the potential applications of jellyfish aquaculture for food, feed, as source of bioactive compounds for pharmaceutical and other biotechnological applications, as well as to supply the marine aquarium trade. Overall, this work aims to raise awareness on the relevance that jellyfish will likely play on the development of sustainable blue bioeconomy frameworks fostering a sustainable valorisation of marine living resources.
- Trophic links and nutritional condition of fish early life stages in a temperate estuaryPublication . Primo, Ana Lígia; Correia, Catarina; Marques, Sónia Cotrim; Martinho, Filipe; Leandro, Sérgio; Pardal, MiguelThe physiological and nutritional condition of fish larvae affect their survival and thus, the success of estuaries as nursery areas. Fatty acid composition has been useful to determine fish nutritional condition, as well as trophic relationships in marine organisms. The present study analyses the fatty acid (FA) composition of fish larvae during spring and summer in the Mondego estuary, Portugal. FA composition, trophic markers (FATM) and fish nutritional condition was analysed for Gobiidae and Sardina pilchardus larvae and the relationships with the local environment evaluated. Results showed that both taxa differed mainly in the stearic acid (C18:0) and eicosapentaenoic acid (EPA) content, with important amounts in Gobiidae and S. pilchardus, respectively. Gobiidae larvae presenting high nutritional condition and omnivore FATM. Fatty acid composition seems to be related with their natural habitat selection and food availability, while fish larvae nutritional condition also showed a strong link with the water temperature and presence of potential predators. This study suggests that FA composition can be a useful tool in assessing planktonic trophic relationships and in identifying species natural habitat.
- Zooplankton distribution in a marine protected area: The Berlengas Natural Reserve, Western Coast of PortugalPublication . Mendes, Susana; Marques, Sónia Cotrim; Azeiteiro, Ulisses Miranda; Fernández-Gómez, Mª José; Galindo-Villardón, Mª Purificación; Maranhão, Paulo; Morgado, Fernando; Leandro, Sérgio MiguelZooplankton distribution in the Berlengas Natural Reserve (Portugal) was studied over a period of one year (February 2006 to February 2007). Monthly sampling was performed at 6 stations, differentiated according to depth and distance to the coastline. The aim of this study was to investigate the overall zooplankton variability through its different dimensions (space vs. time). The Partial Triadic Analysis (PTA) was used to study the spatial variability of the zooplankton community and its dynamics in time and the dynamic trajectories of the zooplankton species for each site. It was possible to distinguish a neritic-ocean gradient of the zooplankton composition and a temporal variability. Four distinct periods can be highlighted considering the distribution of the dates and the arrangement of the species: (i) the first one comprised August to November, (ii) the second one was related to June and July, (iii) the third one associated with spring (April and May) and, (iv) the latest one was related to winter (February, March and December 2006 and January and February 2007). The PTA method showed the similarities between the successive data tables and proved to be useful for investigating biotic structures and detecting spatial-temporal patterns in zooplankton distribution.
- Interannual abundance changes of gelatinous carnivore zooplankton unveil climate-driven hydrographic variations in the Iberian Peninsula, PortugalPublication . D'Ambrosio, Mariaelena; Molinero, Juan C.; Azeiteiro, Ulisses M.; Pardal, Miguel A.; Primo, Ana L.; Nyitrai, Daniel; Cotrim Marques, SóniaThe persistent massive blooms of gelatinous zooplankton recorded during recent decades may be indicative of marine ecosystem changes. In this study, we investigated the potential influence of the North Atlantic climate (NAO) variability on decadal abundance changes of gelatinous carnivore zooplankton in the Mondego estuary, Portugal, over the period 2003e2013. During the 11-year study, the community of gelatinous carnivores encompassed a larger diversity of hydromedusae than siphonophores; the former dominated by Obelia spp., Lizzia blondina, Clythia hemisphaerica, Liriope tetraphylla and Solmaris corona, while the latter dominated by Muggiaea atlantica. Gelatinous carnivore zooplankton displayed marked interannual variability and mounting species richness over the period examined. Their pattern of abundance shifted towards larger abundances ca. 2007 and significant phenological changes. The latter included a shift in the mean annual pattern (from unimodal to bimodal peak, prior and after 2007 respectively) and an earlier timing of the first annual peak concurrent with enhanced temperatures. These changes were concurrent with the climate-driven environmental variability mainly controlled by the NAO, which displayed larger variance after 2007 along with an enhanced upwelling activity. Structural equation modelling allowed depicting cascading effects derived from the NAO influence on regional climate and upwelling variability further shaping water temperature. Such cascading effect percolated the structure and dynamics of the community of gelatinous carnivore zooplankton in the Mondego estuary.
- The strengths and weaknesses of live fluorescently labelled algae (LFLA) to estimate herbivory in protozooplankton and mixoplanktonPublication . Ferreira, Guilherme Duarte; Figueira, Joana; Marques, Sónia Cotrim; Hansen, Per Juel; Calbet, AlbertThe Live Fluorescently Labelled Algae (LFLA) technique has been used numerous times to estimate microzooplankton herbivory. Yet, it is unknown how mixoplankton (i.e., single-cell organisms that can combine phototrophy and phagotrophy) affect the outcome of this technique. Hence, we conducted a broad-spectrum assessment of the strengths and weaknesses of the LFLA technique, using several mixoplanktonic and protozooplanktonic grazers. Species from different taxonomic groups and different feeding mechanisms were tested in short-term experiments (ca. 5 h) in the laboratory, at different prey concentrations and during light and dark periods of the day. Overall, our findings suggest that the LFLA technique, due to its short-term nature, is an effective tracker of diel ingestion and digestion rates, and can detect new mixoplanktonic predators. We recommend that, irrespective of the prey concentration, incubations to measure grazing rates with this technique should generally be concluded within 1 h (adaptable to the environmental temperature). Nevertheless, our results also call for caution whenever using LFLA in the field: feeding mechanisms other than direct engulfment (like peduncle feeding) may provide severely biased ingestion rates. Furthermore, size and species selectivity are very hard to circumvent. To reduce the effects of selectivity, we propose the combined use of two distinctly coloured fluorochromes (i.e., distinct emission spectra). With this modification, one could either label different size ranges of prey or account for species-specific interactions in the food web.
- Copepod production estimated by combining in situ data and specific temperature-dependent somatic growth modelsPublication . Leandro, Sérgio Miguel; Tiselius, Peter; Marques, Sónia Cotrim; Avelelas, Francisco; Correia, Catarina; Queiroga, HenriqueAlthough growth in adult copepods is frequently assumed to be similar to juvenile growth, some evidence have pointed out that under in situ conditions, it can be lower, with, as a consequence, underestimation of secondary production. In addition, under field conditions, juvenile growth in copepods is close to maximum rates estimated at food-saturated conditions. Based on previous assumptions, this study aimed to test the applicability of a new approach for copepod production estimate, derived from temperature-dependent growth models and in situ data, such as seawater temperature and copepod biomass. For this purpose, site-specific copepod juvenile growth models, defined for Acartia tonsa and A. clausi populations from a Southern European estuary (Canal de Mira, Ria de Aveiro, Portugal), were used and copepod biomass was taken fromzooplankton samples collected during 2 years at six sampling stations. By comparing the obtained results with published data, the feasibility of the approach for copepod secondary production estimates and its applicability in worldwide marine ecosystems was confirmed. Future studies should combine the estimates of adult and juvenile production in order to evaluate its relative contribution and to obtain a more precise estimate of secondary production.
- Dynamics of Decapoda larvae communities in a southwest Iberian estuary: Understanding the impact of different thermal regimesPublication . Monteiro, Marta; Cruz, Joana; Azeiteiro, Ulisses; Marques, Sónia Cotrim; Baptista, Vânia; Teodosio, Maria AlexandraEnvironmental conditions play a pivotal role in shaping the dynamics of meroplanktonic communities, which represent a vital life stage, crucial for successful recruitment. Specifically, temperature can impact the survival and duration of larval development in decapod crustacean species. The objective of this study is to analyze the community of decapod larvae in the Guadiana estuary, located in southwest Iberia. The analysis focuses on the community's taxonomic composition, temporal variability, and the influence of environmental factors. Particularly, the study emphasizes investigating the impacts of different thermal regimes on the abundance of these assemblages. A comprehensive zooplankton sampling program was conducted at a single station in the lower estuary, from 2014 to 2022. The decapod larvae assemblages are dominated by Upogebia spp., followed by Diogenes pugilator, Panopeus africanus, Afropinnotheres monodi, and Polybius henslowii species. The results of structural equation modeling unveiled a strong influence of water temperature and salinity on the community, while chlorophyll-a concentration, river runoff, and the large-scale climatic mode North Atlantic Oscillation (NAO) revealed no impact on the abundance of these assemblages. Overall, the community and the main taxa displayed a positive linear trend in response to increased salinity. However, the effect of increasing temperature varied among species. In the current climatic scenario, water temperature emerges as a critical factor in predicting seasonal variation of the assemblages' abundances, exhibiting a marked seasonality during spring and summer. Predictive models used to investigate future scenarios, Representative Concentration Pathway (RCP) 2.6 and RCP 8.5, defined by the International Panel on Climate Change (IPCC), where the temperature is expected to rise 2 °C and 4.3 °C by 2100, suggest the possibility for an alteration in assemblages' composition, where the abundances of D. pugilator, the second most abundant species, tend to decrease abruptly. Reported evidence, coupled with the typical Mediterranean climate of the region, where extreme climatic events, like marine heatwaves, are becoming more frequent, the high connectivity with the Mediterranean Sea, where invasion by non-indigenous species is increasing, also connected with changes in freshwater discharges, may trigger significant alterations in species dominance and abundance, with ecological and socio-economic implications.
- Ecological features of a rocky intertidal community exposed to sewage effluentPublication . Conde, Anxo; Pacheco, Joana; Marques, Sónia Cotrim; Afonso, André S.; Leandro, Sérgio; Maranhão, PauloSewage is among the largest components of coastal pollution, showing a variable scale and size when causing an impact. In this study, temporal and spatial sewage-related gradients were identified using univariate and multivariate methods. Phosphates and nitrogen-based nutrients, except nitrate, were associated to sewage. Abundance and species richness decrease with distance from the sewage outfall while evenness increased. Filterfeeder bivalves and grazer crustaceans showed preference for the sewage discharge site. Gastropods were more abundant at an intermediate distance, likely reflecting primary production enhancement by sewage. Beta diversity was lower at the location and time with highest sewage loadings. The turnover component of beta diversity expressed as an absolute or proportional value was also useful to detect temporal and spatial sewagerelated gradients. Highly energetic hydrodynamics contributes to ameliorate sewage impacts, yet not enough to veil the effect of pollution in this study.
- Predicting zooplankton response to environmental changes in a temperate estuarine ecosystemPublication . Marques, Sónia Cotrim; Azeiteiro, Ulisses Miranda; Leandro, Sérgio Miguel; Queiroga, Henrique; Primo, Ana Ligia; Martinho, Filipe; Viegas, Ivan; Pardal, Miguel ÂngeloA novel strategy that allows to predict the responses of zooplanktonic species to environmental conditions in an estuarine temperate ecosystem (Mondego estuary) is presented. It uses 12 indicator species from the zooplanktonic Mondego database (102 species) that are common members of the different habitats, characterized by their specific hydrological conditions. Indicator-species analysis (ISA) was used to define and describe which species were typical of each of the five sampling stations in a 4-year study (2003–2006). First, a canonical correspondence analysis (CCA) was carried out to objectively identify the species-habitat affinity based on the relationship between species, stations and environmental data. Response curves for each of the zooplanktonic species, generated by univariate logistic regression on each of the independent variables temperature and salinity, were generally in agreement with the descriptive statistics concerning the occurrence of those species in this particular estuarine ecosystem. Species-specific models that predict probability of occurrence relative to environmental parameters like salinity, water temperature, turbidity, chlorophyll a, total suspended solids and dissolved oxygen were then developed for the zooplanktonic species. The multiple logistic models used contained between 1 and 3 significant parameters and the percentage correctly predicted was moderate to high, ranging from 62 to 95%. The predictive accuracy of the model was assured by direct comparison of model predictions with the observed occurrence of species obtained in 2006 (validation) and from data collected in the early 2000s in another Portuguese estuary - Ria de Aveiro (Canal de Mira), a complex mesotidal shallow coastal lagoon. The regression logistic model here defined, correctly suggested that the distribution of zooplankton species was mainly dependent on salinity and water temperature. The logistic regression proved to be a useful approach for predicting the occurrence of species under varying environmental conditions at a local scale. Therefore, this model can be considered of reasonable application (and should be tested in other estuarine systems) due to its ability to predict the occurrence of individual zooplanktonic species associated with habitat changes.
- Medusa polyps adherence inhibition: A novel experimental model for antifouling assaysPublication . Pinteus, Susete; Lemos, Marco F.L.; Freitas, Rafaela; Duarte, Inês M.; Alves, Celso; Silva, Joana; Marques, Sónia C.; Pedrosa, RuiAlthough in the last decades significant advances have been made to improve antifouling formulations, the main current options continue to be highly toxic tomarine environment, leading to an urgent need for new safer alternatives. For anti-adherence studies, barnacles and mussels are commonly the first choice for experimental purposes. However, the use of these organisms involves a series of laborious and time-consuming stages. In the present work, a new approach for testing antifouling formulations was developed under known formulations and novel proposed options. Due to their high resilience, ability of surviving in hostile environments and high abundance in different ecosystems, medusa polyps present themselves as prospect candidates for antifouling protocols. Thus, a complete protocol to test antifouling formulations using polyps is presented, while the antifouling properties of two invasive seaweeds, Asparagopsis armata and Sargassum muticum, were evaluated within this new test model framework. The use of medusa polyps as model to test antifouling substances revealed to be a reliable alternative to the conventional organisms, presenting several advantages since the protocol is less laborious, less time-consuming and reproductive. The results also show that the seaweeds A. armata and S. muticum produce compounds with anti-adherence properties being therefore potential candidates for the development of new greener antifouling formulations.
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