A mechanistic approach reveals non linear effects of climate warming on mussels throughout the Mediterranean sea

There is a dire need to forecast the ecological impacts of global climate change at scales relevant to policy and management. We used three interconnected models (climatic, biophysical and energetics) to estimate changes in growth, reproduction and mortality risk by 2050, for three commercially and ecologically important bivalves at 51 sites in the Mediterranean Sea. These results predict highly variable responses (both positive and negative) in the time to reproductive maturity and in the risk of lethality among species and sites that do not conform to simple latitudinal gradients, and which would be undetectable by methods focused only on lethal limits and/or range boundaries.

The impact of climate change on Mediterranean intertidal communities: losses in coastal ecosystem integrity and services

As has been shown for other ecosystems, the ecological and socio-economic impacts of climate change on Mediterranean intertidal habitats are highly variable in space and time. We conducted field and laboratory measurements of cellular, ecophysiological and behavioural responses of selected intertidal invertebrates (mussels, gastropods and sponges) and completed a literature review to determine what is known of socioeconomic consequences of these biological changes. Results suggest significant gaps in our knowledge that may impede a complete understanding of likely impacts (physical, biological, and socioeconomic) and that sufficient data for such an analysis is available only for mussels. A…

The effect of the quality of diet on the functional response of Mytilus galloprovincialis (Lamarck, 1819): Implications for integrated multitrophic aquaculture (IMTA) and marine spatial planning

Abstract The integrated multi-trophic aquaculture (i.e., IMTA) is a practice combining organisms with different trophic levels with the final purpose of transforming the continuous waste of food by targeting species into nutrient input for other non-target species. This practice very often involves filter feeders, such as bivalves, by the use of which bioenergetics budgets are strongly influenced by the quality and quantity of different foods. However, to date, scant information is available, to really understand the rebounds of food availability on the growth performances of these harvested biomasses in the natural environment. By choosing the mussel Mytilus galloprovincialis as a model, t…

Predicting effective aquaculture in subtropical waters: A dynamic energy budget model for the green lipped mussel, Perna viridis

Abstract The green lipped mussel, Perna viridis, is an important aquaculture species throughout the Indo-Pacific region where production is often impacted by environmental degradation. To predict the impacts and mitigate against environmental problems due to various kinds of anthropogenic pollution, such as heavy metals and eutrophication, on P. viridis aquaculture a Dynamic Energy Budget (DEB) model was constructed. By integrating species-specific parameters and regional-specific environmental data the DEB model determined how the life history traits of P. viridis respond to changing environmental conditions. Using various levels of basal maintenance costs and food availability to elucidat…

Predictive mechanistic bioenergetics to model habitat suitability of shellfish culture in coastal lakes

Quantitative tools based on mechanistic modelling of functional traits able to enhance the sustainability of aquaculture and most other human activities (i.e. reducing the likelihood of detrimental impacts optimising productions), are especially important factors in the decision to site aquaculture facilities in coastal lakes, ponds and lagoons and, in the case of detrimental impact, to adopt mitigation measures. We tested the ability of mechanistic functional trait based models to predict life history traits of cultivable shellfish in shallow coastal lakes. Dynamic Energy Budget (DEB) models were run to generate spatially explicit predictions of Mytilus galloprovincialis life history (LH) …

A multicenter study on the appropriateness of hospitalization in obstetric wards: application of Obstetric Appropriateness Evaluation Protocol (Obstetric AEP)

The cross-sectional study has been based on the implementation of the Obstetric Appropriateness Evaluation Protocol (OAEP) in seven hospitals to determine inappropriate hospital admissions and days of stay. The outcomes were: inappropriateness of admission and "percentage of inappropriateness" for one hospitalization. A total number of 2196 clinical records were reviewed. The mean percentage of inappropriateness for hospitalization was 22%. The percentage of inappropriateness for the first 10 d of hospitalization peaked in correspondence of the fourth (42%). The logistic regression model on inappropriated admission reported that emergency admission was a protective factor (OR = 0.4) and to …

Taking the acid test: Mediterranean limpets face up to climate change

Impacts of climate change involve the interactions of multiple stressors on intertidal organisms, but rarely are the impacts of these stressors examined together. Many tests are also conducted in artificial, controlled laboratory conditions, without making use of natural opportunities to test performance of organisms under different environmental stressors. Given its small tidal range, the Mediterranean Sea provides such an opportunity, with a very fine scale environmental gradient and species living very close to each other over the tidal gradient. The vertical distribution of the limpets, Patella rustica and P. caerulea overlap in Palermo, Sicily, but despite this they have different ther…

Life history traits to predict biogeographic species distributions in bivalves

Organismal fecundity (F) and its relationship with body size (BS) are key factors in predicting species distribution under current and future scenarios of global change. A functional trait-based dynamic energy budget (FT-DEB) is proposed as a mechanistic approach to predict the variation of F and BS as function of environmental correlates using two marine bivalves as model species (Mytilus galloprovincialis and Brachidontes pharaonis). Validation proof of model skill (i.e., degree of correspondence between model predictions and field observations) and stationarity (i.e., ability of a model generated from data collected at one place/time to predict processes at another place/time) was provid…

Functional role of biofouling linked to aquaculture facilities in Mediterranean enclosed locations

Biofouling is generally considered a serious threat for human coastal activities such as aquaculture, and the ecological role of fouling organisms associated with fish-farm cages remains one of the most debated topics in the ecological field. However, although biofouling may cause significant problems related to human health, environmental impact and financial losses, in the past decade there has been an increasing interest in developing methods to promote the growth of biofouling on artificial structures as a strategy to mitigate human impacts and reduce the organic enrichment caused by net-cage fish farming. Here we investigated the filtration activity of biofouling assemblages colonizing…

Predicting biological invasions in marine habitats through eco-physiological mechanistic models: a case study with the bivalveBrachidontes pharaonis

Aim We used a coupled biophysical ecology (BE)-physiological mechanistic modelling approach based on the Dynamic Energy Budget theory (DEB, Dynamic energy budget theory for metabolic organisation, 2010, Cambridge University Press, Cambridge; DEB) to generate spatially explicit predictions of physiological performance (maximal size and reproductive output) for the invasive mussel, Brachidontes pharaonis. Location We examined 26 sites throughout the central Mediterranean Sea. Methods We ran models under subtidal and intertidal conditions; hourly weather and water temperature data were obtained from the Italian Buoy Network, and monthly CHL-a data were obtained from satellite imagery. Results …

The effect of lowered pH on shelled organisms of shallow waters: the case of Brachidontes pharaonis (Mollusca, Bivalvia).

Clearance and respiration rates of shallow Chondrilla nucula at varying temperature.

Dynamic Energy Budget parameters of Brachidontes pharaonis, a lessepsian bivalve in the Mediterranean Sea.

Dynamic Energy Budget (DEB) models are used for describing the flow of energy through organisms. The most important and powerful aspect of DEB theory is that inter-specific differences can be captured in the same model by comparison of parameter values. However, estimation of these parameters is complicated and can often not be done with direct empirical measurements alone. Here, we present DEB parameter estimates obtained by combining both experimental and literature data for the filter feeder Brachidontes pharaonis, which is considered one among the 100 worst invasive marine species in the Mediterranean Basin. We utilize a statistical procedure based on the covariation method to obtain pa…

Effetto dell’impatto antropico e geometria del substrato sulla distribuzione e struttura delle comunità bentoniche vegetali di fouling

Thinking beyond organism energy use: a trait-based bioenergetic mechanistic approach for predictions of life history traits in marine organisms

The functional trait-based bioenergetic approach is emergent in many ecological spectra, from the conservation of natural resources to mitigation and adaptation strategies in a global climate change context. Such an approach relies on being able to exploit mechanistic rules to connect environmental human-induced variability to functional traits (i.e. all those specific traits defining species in terms of their ecological roles) and use these to provide estimates of species life history traits (LH; e.g. body size, fecundity per life span, number of reproductive events). LHs are species-specific and proximate determinants of population characteristics in a certain habitat. They represent the …

Concurrent environmental stressors and jellyfish stings impair caged European sea bass (Dicentrarchus labrax) physiological performances

9 pages, 5 figures, 4 tables

Estimation of dynamic energy budget parameters for the Mediterranean toothcarp (Aphanius fasciatus)

Organisms adopt different sets of physiological, behavioural and morphological trade-offs in order to cope with natural environmental fluctuations. This has consequential rebounds on ecological processes and population dynamics. Such aspects become crucial for sex-dimorphic species, where sex-specific growth variation could mirror different tactics both in energy acquisition and investment between maximum female and male body size with cascading effects on population demography. To date, different approaches have been used in order to understand the causes of individual growth rate changes in ectotherm indeterminate growers, most of which failed. Here, we propose the use of a mechanistic mo…

L’analisi meccanicistica dei tratti funzionali degli organismi per predire gli effetti del disturbo sugli ecosistemi.

Local consumers are the first line to control biological invasions: a case of study with the whelk Stramonita haemastoma (Gastropoda: Muricidae)

The increasing spread of invasive species in the Mediterranean Sea determines several alterations in local food webs, changing the feeding habits of native organisms. The whelk Stramonita haemastoma is a widespread Mediterranean gastropod that consumes bivalves, barnacles and limpets. Previous studies showed a shift in its diet from the bivalve Mytilaster minimus to the invasive mussel Brachidontes pharaonis, presumably due to a higher energy gain. Here we tested whelks’ preference among natives and a novel prey, calculating the profitability ratio, and integrating those results with biochemical analysis on prey tissues and the routine metabolism of the whelks. Further, we used the scaled f…

Functional consequences of prey acclimation to ocean acidification for the prey and its predator

Ocean acidification is the suite of chemical changes to the carbonate system of seawater as a consequence of anthropogenic carbon dioxide (CO2) emissions. Despite a growing body of evidences demonstrating the negative effects of ocean acidification on marine species, the consequences at the ecosystem level are still unclear. One factor limiting our ability to upscale from species to ecosystem is the poor mechanistic understanding of the functional consequences of the observed effects on organisms. This is particularly true in the context of species interactions. The aim of this work was to investigate the functional consequence of the exposure of a prey (the mussel Brachidontes pharaonis) t…

Eco-physiological response of two marine bivalves to acute exposition to commercial Bt-based pesticide

Microbial products based on the entomopathogenic bacterium Bacillus thuringiensis (Bt) are among the most common biopesticides used worldwide to suppress insect pests in forests, horticulture and agricultural crops. Some of the effects of commercial Bt have been recorded for terrestrial and freshwater non-target organisms but little research is available on marine fauna. Nevertheless, due to the contiguity of agro-ecosystems and coastal habitats, marine fauna may be highly influenced by this control method. We studied the effect of a commercial Bt product on the physiological and ecological responses and the energy budget of two of the most frequent marine intertidal bivalves in the Mediter…

Growth and reproductive simulation of candidate shellfish species at fish cages in the Southern Mediterranean: Dynamic Energy Budget (DEB) modelling for integrated multi-trophic aquaculture

Abstract A Dynamic Energy Budget (DEB) model is used to simulate growth and reproduction of the shellfish Mytilus galloprovincialis and Crassostrea gigas in an integrated multi-trophic aquaculture (IMTA) farm scenario situated in the Southern Mediterranean (the Gulf of Castellammare, Sicily). We modelled the effect of primary production enrichment at fish cages on shellfish growth and life history traits using 4 years-hourly temperature data (01 January 2006–31 December 2009) at a depth of 1 m. Outputs of the DEB simulations were: the maximum theoretical total shell length of shellfish, the potential reproductive outputs and the mean annual von Bertalanffy growth rate. There was a mean incr…

Stima delle riserve energetiche di due specie ittiche (Aphanius fasciatus e Atherina boyeri) delle lagune Siciliane

I limiti della nicchia fondamentale e le temperature di Arrhenius dei bivalvi Brachidontes pharaonis e Mytilaster minimus

An energy budget for the subtidal bivalve Modiolus barbatus (Mollusca) at different temperatures

Clearance rates, respiration rates and food absorption efficiencies of the commercially interesting subtidal bivalve Modiolus barbatus were measured at different temperatures under laboratory conditions and scope for growth calculated. Clearance rates were highest at temperatures from 20 °C to 28 °C, whereas respiration rate was maximal at 9 °C and minimal at 26 °C. Highest mean values of absorbed energy occurred at 20 °C and 26 °C. Scope for growth trend had negative values at 9 °C, 15 °C and 28 °C and positive values at temperatures 20 °C and 26 °C. The profitable thermal window for M. barbatus to have energy sufficient for growth and reproduction corresponded to <5 months per year. Seawa…

Functional consequences of prey acclimation to ocean acidification for the prey and its predator

Ocean acidification is the suite of chemical changes to the carbonate system of seawater as a consequence of anthropogenic carbon dioxide (CO2) emissions. Despite a growing body of evidences demonstrating the negative effects of ocean acidification on marine species, the consequences at the ecosystem level are still unclear. One factor limiting our ability to upscale from species to ecosystem is the poor mechanistic understanding of the functional consequences of the observed effects on organisms. This is particularly true in the context of species interactions. The aim of this work was to investigate the functional consequence of the exposure of a prey (the mussel Brachidontes pharaonis) t…