Latitudinal variations in positive and negative effects of invertebrates on rocky shore biofilm

Marine caves of the Southern Tyrrhenian Sea: a First Census of Benthic Biodiversity

This is the first paper documenting research on a selection of marine caves located along the coast of Capo Milazzo in the southern Tyrrhenian Sea. Three submarine and one semi-submerged caves were surveyed and sampled using underwater photo sampling. Surveys have only taken into account the sessile species belonging to the main taxa: Porifera, Anthozoa, Bryozoa and Polychaeta. Diversity indices and abundances were calculated for three sections within each explored cave: the Entrance Zone, Intermediate Zone and Bottom Zone. The richest group was Porifera with 21 taxa, followed by cnidarians, (Anthozoa), with 8 taxa, Polychaeta (5 taxa), and Bryozoa (5 taxa). Among Porifera, the presence of …

Quantificazione degli effetti della protezione sul benthos di substrato duro: risultati di un esperimento condotto in 15 aree marine protette (AMP) Italiane.

DO INVASIVE MACROALGAE INFLUENCE ASSOCIATED MOLLUSC DIVERSITY IN THE MEDITERRANEAN SEA ?

The benthic molluscs associated to the non-indigenous red algae Asparagopsis taxiformis invading the Mediterranean rocky subtidal were compared with those associated to a native brown alga. The results showed a marked difference in species richness and abundance between native and non-native algal species.

PROSPETTIVE E CRITICITÀ SUL RUOLO DEL BENTHOS MEDITERRANEO NELLA DIRETTIVA SULLA MARINE STRATEGY

In Europe, the Marine Strategy Framework Directive (MSFD) and the Water Framework Directive (WFD) are the main regulations for the protection of water bodies. The translation of their principles into valid and practical approaches is the main challenge for the scientific community. An additional and even more severe problem is related to the MSFD application in the Mediterranean area. The aim of the present contribution is to picture the present situation in Italy, as far as the benthic communities in the MSFD are concerned, pinpoint some conceptual and practical critical points, and possibly suggest some new tools useful for the definition of Good Ecological Status (GES).

Settlement performance of the Mediterranean reef-builders Dendropoma cristatum (Biondi 1859) in response to natural bacterial films.

The gastropod Dendropoma cristatum is a biogenic engineer of the central Mediterranean, forming reefs along the lower rocky intertidal fringe with a remarkable ecological role. To understand whether reef-associated biofilm cultivable bacterial and biofilm ageing may trigger the settlement of the juvenile snails, a combination of laboratory techniques and field experiments was used. Reef-associated biofilm cultivable bacteria were isolated, and a settlement-choice experiment was performed in situ on artificial biofilms composed of i) a mixture of six biofilm-forming selected isolates, ii) all the cultivable bacteria, and iii) 13-, 23-, 32-day old biofilms formed under natural conditions. Ove…

Variazioni in struttura e ricchezza specifica della fauna ittica: effetti del fish feeding nell’isola di Ustica.

Nest-mediated parental care in a marine fish: Are large-scale nesting habitats selected and do these habitats respond to small-scale requirements?

Fishes have evolved various reproductive strategies including mechanisms that involve parental care and demersal eggs laid into nests. Symphodus ocellatus has a seasonal reproduction period during which large, dominant males become territorial and build nests with fragments of algae, where they attract females to spawn and provide care to the developing eggs. Based on the hypothesis that the S. ocellatus males choose the reproductive habitat based on some characteristics of the substrate, here we assessed whether, on a coastal area scale, the distribution of this species changes during the reproductive period because of the selection of some suitable sites or substrates, and whether the nes…

DISTRIBUTION PATTERNS OF TWO LABRID SPECIES IN THE WESTERN MEDITERRANEAN: IS WATER WARMING AFFECTING THEIR ECOLOGICAL INTERACTIONS?

Climate warming should favor ‘warm water’ species over ‘cold water’ species at the same site. Regional warming in the Western Mediterranean has allowed the documented northward expansion of southern marine species. Conversely, very little is known on the response of cold loving species to temperature variations. We propose to work with two common coastal fishes: the rainbow wrasse Coris julis and the ornate wrasse Thalassoma pavo, with the general objective to exploring patterns of distribution and their potential to interact under warming conditions. Large scale quantitative observations revealed: (1) opposing trends in abundance along latitudinal (35o − 45oN) and depth gradients (0-36m), …

Italian marine reserve effectiveness: does enforcement matter?

Marine protected areas (MPAs) have become popular tools worldwide for ecosystem conservation and fishery management. Fish assemblages can benefit from protection provided by MPAs, especially those that include fully no-take reserves. Fish response to protection can thus be used to evaluate the effectiveness of marine reserves. Most target fish are high-level predators and their overfishing may affect entire communities through trophic cascades. In the Mediterranean rocky sublittoral, marine reserves may allow fish predators of sea urchins to recover and thus whole communities to be restored from coralline barrens to macroalgae. Such direct and indirect reserve effects, however, are likely t…

CO2 vents areas show effects of ocean acidification on benthic rocky shores assemblages

Relazioni tra la morfologia costiera e la struttura di popolazione di Dendropoma petraeum (Mollusca, Vermetidae).

Food resource partitioning between two sympatric temperate wrasses

The present study analysed two sympatric wrasses, Thalassoma pavo and Coris julis, with similar sizes and morphologies, that are widespread in the reef habitats of the Mediterranean and the eastern Atlantic coast. Ocean warming has induced the northward movement of T. pavo, whereas C. julis has been moving to deeper habitats. In addition, under conditions of high slope of the sea bottom, T. pavo occupies shallow habitats and C. julis is in greater abundance in deeper habitats. By investigating stomach contents and prey availability in the benthos, we assessed whether the two wrasses exploit food resources by choosing different prey within the same habitat both under co-existence and segreg…

Seagrass detritus as marine macroinvertebrates attractor

Seagrasses colonise coastal areas worldwide. Despite their high primary production, a considerable proportion becomes detritus that can be used as food, physical habitat and occasional or permanent shelter by several benthic macroinvertebrates. In turn, macroinvertebrates can contribute to regulating seagrass decomposition, and represent an important trophic link between primary producers and higher consumers. Nonetheless, several factors could modify colonizer responses to this habitat. In this study, we tested if colonisation of the seagrass detritus of Zostera noltei Hornemann, 1832 was related to substrate availability rather than food and whether the colonising assemblages were similar…

Does refuge complexity affect intertidal crabs population structure ?

Un approccio a grande scala per la classificazione dell'ambiente costiero

L’uso della biodiversita’ nella zonizzazione delle aree marine protette: un’applicazione nelle Isole Egadi.

Effetti di differenti tipologie di impatto antropico sui reef a vermeti.

Evaluation of the impact of a small marina on intertidal assemblages

Body size and mating strategies in the simultaneous hermaphrodite Oxynoe olivacea (Mollusca, Opisthobranchia, Sacoglossa).

Summary 1To better understand the role and importance of body size in hermaphroditic mating system theory, the mating behaviour of the shelled sacoglossan Oxynoe olivacea was studied. This simultaneous hermaphrodite exhibits bilateral and unilateral sperm transfer and thus it is particularly suitable for studies on hermaphrodite sexual conflict. 2In this study three hypotheses on body size were tested: that O. olivacea partner size has an effect on (i) mating mode choice, (ii) duration of mating modes, and (iii) choice of sexual role. Furthermore, we tested Charnov's hypothesis that in O. olivacea, like many simultaneous hermaphrodites, a sexual conflict exists and the male role is preferre…

Meiofauna associated with vermetid reefs: the role of macroalgae in increasing habitat size and complexity

We present the first dataset of meiofauna associated with vermetid reefs (biogenic constructions of Mediterranean intertidal habitat) in two areas along the northern coast of Sicily, Italy. The vermetid reefs are characterized by a horizontal extension from the shore towards the open sea and can be divided into three zones (the inner margin, the cuvette zone and the outer margin) which differ in hydrodynamic features. We studied the spatial distribution of meiofauna along the horizontal axis of the vermetid reefs, investigating the communities inhabiting the sediment inside cuvettes (shallow pools inside the “cuvette zone”) located between the inner and the outer margins of the reefs. We ob…

Ecological effects in EMPAFISH case studies: Ustica Island.

Human recreational activities within Mediterranean marine protected areas: lessons learnt in the Ustica Island MPA.

Temporal dynamic of biofilms enhances the settlement of the central-1 Mediterranean reef2 builder Dendropoma cristatum (Biondi, 1859)

Research on marine invertebrate settlement provides baseline knowledge for restoration technique implementation, especially for biogenic engineers with limited dispersion ability. Previously, we determined that the maturity of a biofilm strongly enhances the settlement of the vermetid reef-builder Dendropoma cristatum . In order to elucidate which biofilm features support a higher settlement of this species, we analyse the structure and composition of a marine biofilm over time, through microscopic observations, eukaryotic and prokaryotic fingerprinting analyses and 16S rDNA Illumina sequencing. The vermetid settlement temporal increase matched with the higher biofilm extent on the substrat…

Characterization of mitotic and meiotic, chromosomes of the vermetid gastropodDendropoma (Novastoa) Petraeum(Monterosato, 1884) (Mollusca, Caenogastropoda)

Abstract The vermetid gastropod Dendropoma (Novastoa) petraeum from the Northwestern coast of Sicily was investigated karyologically. The count of spermatocyte bivalents at diakinesis gave the haploid number of this species as n=17. The count of mitotic chromosomes in males, females and early developing embryos gave the diploid number as 2n=34. Irrespective of sex, the karyotype of D. petraeum consists of 17 homomorphic chromosome pairs, of which 8 are metacentric, 4 subtelocentric and 5 acrocentric. This species is characterized by the presence of two chromosomes per cell involved in nucleolus organization (NOR) and by a low amount of constitutive heterochromatin.

Effetti indiretti del pascolamento dei ricci sul benthos costiero: variazioni nella malacofauna.

Valutazione della vulnerabilità alla frequentazione subacquea di grotte sommerse: applicazione in tre AMP italiane

Applicazione dei metodi dell'ecologia del paesaggio all'ambiente marino: l'analisi spaziale e temporale del mosaico ambientale sulle piattaforme a vermeti.

Bottom slope affects the distribution of two labrid species in the Mediterranean infralittoral

Small-scale patches of detritus as habitat for invertebrates within a Zostera noltei meadow

Abstract Seagrass detritus can attract numerous invertebrates as it provides food and substrate within the meadow or in adjacent environments. Nonetheless, several factors could modify the invertebrate response to this habitat. In this study, we tested if epifaunal colonisation of Zostera noltei detritus was related to substrate availability rather than food and whether colonising assemblages were similar according to the meadow structural complexity. Litterbags filled with natural or artificial detritus were deployed within an eelgrass meadow in a Mediterranean coastal lagoon (Thau lagoon, France). Colonisation appeared to be driven by the presence of detritus, with similar assemblages in …

Towards a local mass mortality of the Mediterranean orange coral Astroides calycularis (Pallas, 1766) in the Pelagie Islands Marine Protected Area (Italy)

In late summer 2020, a widespread mortality event severely affected colonies of the Mediterranean endemic orange coral Astroides calycularis in the Pelagie Islands (Strait of Sicily, southern Mediterranean Sea). The degree of the mortality impact at seven study sites of the archipelago (five within the Pelagie Islands Marine Protected Area) was quantified by estimating the proportion of affected colonies in populations of A. calycularis. Five of the seven surveyed sites revealed a low degree of impact, but Punta Ruperta and Cala Creta (both on the island of Lampedusa) showed a medium impact with values of 32.3% and 30.5% of affected colonies respectively. The 2020 mortality event coincided …

Preservation of modern and mis 5.5 erosional landforms and biological structures as sea level markers: A matter of luck?

The Mediterranean Basin is characterized by a significant variability in tectonic behaviour, ranging from subsidence to uplifting. However, those coastal areas considered to be tectonically stable show coastal landforms at elevations consistent with eustatic and isostatic sea level change models. In particular, geomorphological indicators—such as tidal notches or shore platforms—are often used to define the tectonic stability of the Mediterranean coasts. We present the results of swim surveys in nine rocky coastal sectors in the central Mediterranean Sea using the Geoswim approach. The entire route was covered in 22 days for a total distance of 158.5 km. All surveyed sites are considered to…

METODOLOGIE DI ANALISI DEL PAESAGGIO NELLA VALUTAZIONE DELL’ETEROGENEITÁ STRUTTURALE NEI REEF A VERMETI

Landscape ecology is a discipline that uses many indices to describe environmental dynamics as a function of structural patch organization. Application of landscape ecology methods can be a way to evaluate heterogeneity and fragmentation of a habitat. Landscape indices were applied to evaluate if the algal heterogeneity of a vermetid reef can be related to the reef structure. Results show that heterogeneity is independent from reef width, but algal patches are wider and less abundant in a large cuvette and less wide but in higher number in small cuvette.

Ocean acidification and elevated temperature negatively affect recruitment, oxygen consumption and calcification of the reef-building Dendropoma cristatum early life stages: Evidence from a manipulative field study

Expected temperature rise and seawater pH decrease may affect marine organism fitness. By a transplant experiment involving air-temperature manipulation along a natural CO2 gradient, we investigated the effects of high pCO(2) (similar to 1100 mu atm) and elevated temperature (up to +2 degrees C than ambient conditions) on the reproductive success, recruitment, growth, shell chemical composition and oxygen consumption of the early life stages of the intertidal reef-building vermetid Dendropoma cristatum. Reproductive success was predominantly affected by temperature increase, with encapsulated embryos exhibiting higher survival in control than elevated temperature conditions, which were in t…

Signals of loss: Local collapse of neglected vermetid reefs in the western Mediterranean Sea

During the summer of 2022, an extensive die-off of Dendropoma cristatum and other marine organisms associated with vermetid reefs was observed in the western Mediterranean Sea (northern coast of Sicily). Quantitative data from more than 300 km of coastal stripe indicated that the percentage of dead D. cristatum specimens, showing empty and/or transversely fractured shells, ranged from 64 to 84 % in populations having a density of 2900-4730 ind./m2, suggesting that millions of organisms had recently died along the Sicilian coast. This high mortality range coincided with prolonged desiccation events during which biogenic vermetid reefs were exposed to extreme warm-air conditions for several c…

Human recreational activities in Mediterranean marine protected areas: lessons learnt in the Ustica Island MPA.

Vermetid reefs in the Mediterranean Sea as archives of sea-level and surface temperature changes

Vermetid reefs are among the most important bioconstructions in the Mediterranean Sea, with a distribution restricted to the warmest part of the basin. Their structure, and vertical and geographical distribution make them good biological indicators of changes in sea level and sea-surface temperature over the last two millennia.

The neglected status of the vermetid reefs in the Mediterranean Sea: A systematic map

Studied since late 1800, vermetid reefs are marine bioconstructions of well-acknowledged importance in the Mediterranean Sea. Despite their persistence being jeopardized in the whole basin, recent studies have referred to this bioconstruction as a neglected habitat. In this study, we assessed the neglected status of the Mediterranean vermetid reefs in the scientific literature producing a systematic map through a multi-method bibliometric protocol. Scopus and Web of Science databases were jointly used for data collection. Vermetid reefs publication rate (i.e., number of publications per year) was investigated compared to the other Mediterranean bio-constructions using ANOVA analysis and Zer…

Struttura di popolazione di Haliotis tuberculata in aree soggette a diversi livelli di protezione.

Analisi preliminare delle risposte della comunità intertidale a variazioni di pCO2 e temperatura

La principale conseguenza delle emissioni atmosferiche di CO2 di origine antropica è l’incremento dell’effetto serra, che sta conducendo al fenomeno del riscaldamento globale. Una parte di queste emissioni viene sequestrata dagli oceani causando profondi cambiamenti nella chimica dei carbonati, un processo noto come acidificazione degli oceani. La temperatura ed il pH possono interagire fra loro inducendo cambiamenti nelle risposte delle comunità marine. Questo studio si propone di valutare sperimentalmente la risposta del biofilm a cambiamenti indotti di temperatura e pCO2 lungo un gradiente di chimica dei carbonati nell’Isola di Vulcano (Isole Eolie).

A conceptual framework for the integral management of marine protected areas

A general conceptual framework for the management of marine protected areas (MPAs) was developed. The driver-pressure-state-impacts-response (DPSIR) framework was used to determine the elements affecting MPAs. The developed evaluation framework helped to select an appropriate suite of indicators to support an ecosystem approach, an assessment of the MPAs functioning and policy decisions. Gaps derived from the management and policy responses in the MPAs were also outlined. It was concluded that the DPSIR framework can help to simplify the complexity of MPA management. This document is a tool for policy makers, scientists and general public on the relevance of indicators to monitor changes an…

Can recreational scuba divers alter natural gross sedimentation rate? A case study from a Mediterranean deep cave

Abstract Di Franco, A., Ferruzza, G., Baiata, P., Chemello, R., and Milazzo, M. 2010. Can recreational scuba divers alter natural gross sedimentation rate? A case study from a Mediterranean deep cave. – ICES Journal of Marine Science, 67: 871–874. Submarine caves are environments with features distinguishing them from other littoral habitats but, despite their ecological importance, their response to anthropogenic disturbance has been seldom verified. One potential threat affecting natural communities within caves is represented by recreational scuba diving. Divers' disturbance within marine caves is mainly related to physical contacts and increased sediment resuspension potentially affecti…

Effects of ocean acidification on rocky shore communities at Vulcano Island

Recruitment patterns in an intertidal species with low dispersal ability: the reef-building Dendropoma cristatum (Biondi, 1859) (Mollusca: Gastropoda)

In the Mediterranean, the gastropod Dendropoma cristatum (sin. D. petraeum (Monterosato, 1884)) is the primary builder of the vermetid reef, an intertidal bioconstruction of exceptional ecological importance. Despite awareness of the need for conservation of this key species, the biology of D. cristatum remains poorly understood. The recruitment of D. cristatum deserves particular attention because the absence of a planktonic larval stage limits its dispersal ability. We examined the temporal pattern of recruitment during the breeding season of D. cristatum from June to September in 2013. Specifically, we compared the two portions of the vermetid reef (i.e. the inner edge and the outer edge…

Marine protected areas overall success evaluation (MOSE): A novel integrated framework for assessing management performance and social-ecological benefits of MPAs

International audience; Characterized by interlinked social, economic, and ecological dynamics, Marine Protected Areas (MPAs) are a management tool for achieving sustainability goals in social-ecological systems. The recent increase in their establishment worldwide, fostered by international policies, highlights the need for comprehensive and integrated assessment frameworks able to address the evaluation of their social-ecological effectiveness and management performance, which is of fundamental importance for their adaptive management and decision making processes. Although several indicators and methodologies exist to assess MPAs ecological or social performances, no comprehensive assess…

Evaluation of the Ustica Island MPA efficacy after ten years of protection.

Substratum recognition as settlement cue for larvae of Dendropoma cristatum (Biondi, 1859)

Despite the ecological relevance of the vermetid bioconstructions in the Mediterranean, little is known about the early life stage of Dendropoma cristatum. This study describes the preference for settlement substrata from D. cristatumlarvae. A field experiment was carried out to test the suitability of crustose coralline algae (CCA), D. cristatumadults and two inorganic substrata as settlement surfaces. The number of settling larvae varied among the four treatments with higher settlement success on organic surfaces. CCA and D. cristatumindividuals seem to promote attachment of young larvae and to induce the metamorphosis in recruits. This is probably due to biological or physical properties…

Defining indicators to assess the effects of protection in MPAs.

Mediterranean bioconstructions along the Italian coast

Marine bioconstructions are biodiversity-rich, three-dimensional biogenic structures, regulating key ecological functions of benthic ecosystems worldwide. Tropical coral reefs are outstanding for their beauty, diversity and complexity, but analogous types of bioconstructions are also present in temperate seas. The main bioconstructions in the Mediterranean Sea are represented by coralligenous formations, vermetid reefs, deep-sea cold-water corals, Lithophyllum byssoides trottoirs, coral banks formed by the shallow-water corals Cladocora caespitosa or Astroides calycularis, and sabellariid or serpulid worm reefs. Bioconstructions change the morphological and chemicophysical features of prima…

Exploring the development of scientific research on Marine Protected Areas: From conservation to global ocean sustainability

Abstract Marine Protected Areas (MPAs) are playing a central role in the achievement of ocean sustainability and, since 2000, their global coverage has increased over ten times. The success of MPAs, and therefore the delivery of their potential outcomes for human well-being and global sustainability, requires multi-disciplinary, holistic, and comprehensive approaches for its achievement. In this study, the global scientific literature on MPAs was quantitatively reviewed through bibliometrics approaches, investigating patterns and trends in its development over time. In particular, bibliometric network and citation burst analyses of keywords were performed using VOSviewer and CiteSpace softw…

Le aree di transizione siciliane: stato dell’arte e sviluppi futuri

LE BIOCOSTRUZIONI MARINE IN MEDITERRANEO. LO STATO DELLE CONOSCENZE SUI REEF A VERMETI

Vermetid reefs are among the more important bioconstruction of the Mediterranean Sea with a restricted distribution in the southern part of the basin. Their high heterogeneity and the associated biodiversity make their conservation a priority issue for the Mediterranean region

Trophic cascades in benthic marine ecosystems: lessons for fisheries and protected-area management

An important principle of environmental science is that changes in single components of systems are likely to have consequences elsewhere in the same systems. In the sea, food web data are one of the few foundations for predicting such indirect effects, whether of fishery exploitation or following recovery in marine protected areas (MPAs). We review the available literature on one type of indirect interaction in benthic marine ecosystems, namely trophic cascades, which involve three or more trophic levels connected by predation. Because many indirect effects have been revealed through fishery exploitation, in some cases we include humans as trophic levels. Our purpose is to establish how wi…

GE.B.EC.SUD: STUDIO GEOLOGICO, BIONOMICO ED ECOLOGICO DI AREE MARINE PROTETTE DELL’ITALIA MERIDIONALE.RISULTATI

Do small marinas drive habitat specific impacts? A case study from Mediterranean Sea.

Many human activities add new structures to the marine landscape. Despite the fact that human structures cause some inevitable impacts, surprisingly little information exists on the effects of marina on natural marine assemblages. The aim of this paper is to assess habitat-specific response of benthic sessile organisms of rocky shores in relation to the presence of a small marina. Sampling was carried out at three coastal habitats (midshore, lowshore and subtidal) by means of visual censuses adopting an after-control-impact (ACI) experimental design. It appears that the marina affects the structure and composition of benthic communities of both the midshore and the lowshore. Little effect w…

Biological diversity of the microbial film associated to the central-Mediterranean Dendropoma cristatum (Biondi, 1859) reefs.

Microbial films may provide physical and bio-chemical cues which positively affect the settlement dynamic of a variety of benthic marine organisms, driving the development of ecosystems. Also for the Mediterranean intertidal reef-builder Dendropoma cristatum (Biondi, 1859), biofilm maturity has been found to enhance the settlement pattern. However, the microbial diversity associated with these bioconstructions has never been described. This study investigates the D. cristatum reef bacterial assemblage composition and temporal evolution in two localities in the northwest of Sicily. Biological diversity of the reef-associated biofilm and of 3 progressively older biofims obtained on artificial…

Percorsi subacquei all’interno di aree marine protette: un approccio fuzzy per la definizione di un valore di vulnerabilità.

Sicilian transitional waters: Current status and future development

To appraise the current knowledge of Sicilian transitional waters (TWs), a review was undertaken of the information available on these ecosystems. In detail, a synthesis of the current status is reported, highlighting for each area the ecological features and status, historical data, conservation regime, environmental emergencies and anthropic pressures to which they are subject. The Sicilian TWs reviewed include coastal ponds and lakes, mires and areas with active and nonactive saltworks. Almost all of these ecosystems are affected by several protection regimes because of their high naturalistic value, although current knowledge is limited and fragmented. A few areas have received more att…

Evaluation of Scuba divers’ behaviour and of its effects on the biota in a Mediterranean MPA.

Remarkable presence of Aplysia punctata (Mollusca, Opisthobranchia, Anaspidea) in the Ustica Island MPA (Western Mediterranean, Italy)

Valutazione dell’impatto di un piccolo porto sui popolamenti bentonici di substrato duro.

Gli effetti degli incendi sul popolamento a Molluschi Gasteropodi di macchia mediterranea.

Selezione dell’habitat in Haliotis tuberculata.

ANALISI DELL’ETEROGENEITA’ BIOCENOTICA LUNGO LA FASCIA COSTIERA DELLE ISOLE DI USTICA E MARETTIMO

Invasive mussels directly threat intertidal vermetid reef: some evidences from a Sicilian MPA

Biological invasions pose a great threat to natural communities. Brachidontes pharaonis is an Eritrean mussel that has accessed in the Mediterranean sea shortly after the opening of the Suez Canal. At the beginning it had a restrained distribution with small local populations along the Israeli intertidal coast. More than a hundred years later it spread westward as far as NW Sicily, colonizing some hyperaline and natural habitats. Previous studies along the Israeli coast have proved that anthropogenic habitat modi#- cations occurring on vermetid reefs may promote the colonization of this invasive mussel causing a reduction of the indigenous mussel Mytilaster minimus. This study focuses on a …

Ocean acidification impairs vermetid reef recruitment

Vermetids form reefs in sub-tropical and warm-temperate waters that protect coasts from erosion, regulate sediment transport and accumulation, serve as carbon sinks and provide habitat for other species. The gastropods that form these reefs brood encapsulated larvae; they are threatened by rapid environmental changes since their ability to disperse is very limited. We used transplant experiments along a natural CO2 gradient to assess ocean acidification effects on the reef-building gastropod Dendropoma petraeum. We found that although D. petraeum were able to reproduce and brood at elevated levels of CO2, recruitment success was adversely affected. Long-term exposure to acidified conditions…

Do small marinas drive habitat specific impacts? A case study from Mediterranean Sea

Many human activities add new structures to the marine landscape. Despite the fact that human structures cause some inevitable impacts, surprisingly little information exists on the effects of marina on natural marine assemblages. The aim of this paper is to assess habitat-specific response of benthic sessile organisms of rocky shores in relation to the presence of a small marina. Sampling was carried out at three coastal habitats (midshore, lowshore and subtidal) by means of visual censuses adopting an after-control-impact (ACI) experimental design. It appears that the marina affects the structure and composition of benthic communities of both the midshore and the lowshore. Little effect w…

Biodiversità e zonizzazione di aree marine protette.

Patterns of algal recovery and small-scale effects of canopy removal as a result of human trampling on a Mediterranean rocky shallow community.

The ecological importance of marine algae is widely known but in shallow coastal areas the composition and structure of algal communities may be affected by different human activities. Recovery from different trampling disturbances of two competing morphological groups (i.e. macroalgae and algal turfs) and effects of macroalgal canopy removal on the dominant associated fauna were examined using controlled trampling experiments. Six months after trampling disturbance was removed, the two morphological groups closely resembled control (untrampled) conditions, both in terms of cover and canopy (%). In particular, macroalgal recovery seemed to be very rapid: the higher the impact on the system …

The Mediterranean vermetid reefs: distribution and conservation status

The vermetid reef is an intertidal bioconstruction distributed in the warmest waters of the Mediterranean Sea, and is built by the gregarious vermetid gastropodDendropomaspp. cemented by the coralline red algae of the genusNeogoniolithon.Thisbiogenichabitatisonly generically protected under the European Habitat Directive, but to date it is not explicitly taken into account in many conservation plans. Despite the documented local extinction of Dendropomain the some Eastern Mediterranean locations, its role as habitat engineer and the high numbers of ecosystem services provided, vermetid reef is among the least known marine bioconstruction of the Mediterranean. We counted 112 reefs along the …

L'uso della biodiversità nella zonizzazione della aree marine protette: un'applicazione nelle Isole Egadi.

Developing a scuba trail vulnerability index (STVI): a case study from a Mediterranean MPA

Scuba diving is now one of the major form of commercial use of marine protected areas (MPAs) around the world and the control of its potential impacts on the marine environment represents a fundamental key to manage this recreational activity in highly dived areas. A potential tool to tackle such issues has been thought to be the definition of a value of recreational carrying capacity of an area, but this approach has been rarely considered management-effective. Therefore, the first step for effectively managing scuba-diving should be ‘bottom-up’: characterizing the benthic communities potentially affected by diving and evaluating their vulnerability. Aim of this paper is to propose a tool …

A posteriori application of the "Marep" to the zonation of the Egadi Island.

Effetti del turismo subacqueo nell’area marina protetta “Isola di Ustica”.

Selezione dell’habitat in quattro specie ittiche criptobentoniche nell’infralitorale superiore di coste rocciose in Mediterraneo

MPA: USTICA ISLAND.

Effectiveness of European Atlanto-Mediterranean MPAs: Do they accomplish the expected effects on populations, communities and ecosystems?

The success of MPAs in conserving fishing resources and protecting marine biodiversity relies strongly on how well they meet their planned (or implicit) management goals. From a review of empirical studies aiming at assessing the ecological effects of Mediterranean and Macaronesian MPAs, we conclude that establishing an MPA is successful for (i) increasing the abundance/biomass, (ii) increasing the proportion of larger/older individuals, and (iii) enhancing the fecundity of commercially harvested populations; also, MPAs demonstrated to be effective for (iv) augmenting local fishery yields through biomass exportation from the protected area, and (v) inducing shifts in fish assemblage structu…

EFFETTI DELLA PROTEZIONE E DELLA COMPLESSITÀ TOPOGRAFICA SUI POPOLAMENTI BENTONICI DEI REEF A VERMETI

Vermetid reef can be considered a key intertidal habitat of Mediterranean Sea and increasing knowledge about this natural system is important for its conservation. Aims of this study is to assess topography complexity, structure and composition of the benthic assemblages associated to reef formation in a marine protected area highlighting possible effects of the protection.

Evaluating the ecological effects of Mediterranean marine protected areas: habitat, scale and the natural variability of ecosystems

The capability to detect and predict the responses of marine populations and communities to the establishment of marine protected areas (MPAs) depends on the ability to distinguish between the influences of management and natural variability due to the effects of factors other than protection. Thus, it is important to understand and quantify the magnitude and range of this natural variability at each scale of observation. Here we review the scale of responses of target populations and communities to protection within Mediterranean MPAs, against their ‘normal’ spatio-temporal heterogeneity, and compare those with documented cases from other temperate and tropical marine ecosystems. Additiona…

Molluscan assemblages associated with photophilic algae in the Marine Reserve of Ustica Island (Lower Tyrrhenian Sea, Italy)

Abstract Very few studies have addressed the effect of protection on macrozoobenthos in marine protected areas, and particularly for sites in the Mediterranean Sea. In the present study, the molluscan assemblages associated with photophilic algal communities of the Marine Reserve of Ustica Island, were investigated. A survey was carried out along transects from 1 to 15 m in depth, during the spring of 1996 at three different sites, subjected to different levels of reserve protection. Species richness and number of individuals reflected the level of protection, and both variables were significantly higher in the integral (most heavily protected) part of the reserve compared with the less wel…

The size and shape of shells used by hermit crabs: A multivariate analysis of Clibanarius erythropus

Shell attributes such as weight and shape affect the reproduction, growth, predator avoidance and behaviour of several hermit crab species. Although the importance of these attributes has been extensively investigated, it is still difficult to assess the relative role of size and shape. Multivariate techniques allow concise and efficient quantitative analysis of these multidimensional properties, and this paper aims to understand their role in determining patterns of hermit crab shell use. To this end, a multivariate approach based on a combination of size-unconstrained (shape) PCA and RDA ordination was used to model the biometrics of southern Mediterranean Clibanarius erythropus populatio…

Stima degli effetti diretti del calpestio umano sul mosaico ambientale delle piattaforme a vermeti.

Implication of the biofilm ageing for the settlement of the vermetid gastropod Dendropoma cristatum (Biondi 1857)

Dendropoma cristatumreefs are key-intertidal habitats of the central Mediterranean. Knowledge onD. cristatumbiology is presently scant, particularly on its early life stage. The development of embryos occurs inside the maternal shell, and the crawling larvae settle on hard substrates shortly after hatching. Epilithic biofilm is known to have implications in the settlement of many marine invertebrates; however whether biofilm plays a role in driving the vermetid settlement is unknown. In this study the microbial assemblage ageing is tested as apotentialtriggerforD. cristatumsettlement. A field experiment was set-up to compare the larval settlement rate on removable limestone cubes (5x5x2 cm)…

Valutazione dell’efficacia della protezione sui popolamenti bentonici di substrato duro nell’AMP Isola di Ustica.

Nest building in a Mediterranean wrasse (Symphodus ocellatus): are the algae used randomly chosen or actively selected?

To increase their reproductive success, fish species have evolved various strategies, including both simple processes and more complex mechanisms that involve parental care by nest-building. In Symphodus ocellatus, a species that lives in rocky infralittoral zones of the Mediterranean Sea, during the reproductive period, the male builds a nest within a hole or crevice using fragments of algae and/or sand particles. Data on the nesting activity of wrasses are rare, and previous descriptions regarding the algal composition of nests have provided conflicting results. In this regard, it is unclear whether territorial males actively select algal species for nest construction or algal choice is r…

GLI EFFETTI DEL DISTURBO ANTROPICO SULLA TOPOGRAFIA DEL REEF A VERMETI

Intertidal vermetid reefs could be affected by many human disturbances. Using a microtopography device, the authors analysed the changes induced by the accessibility on the surface topography of the reefs. Human activities seems to be able to induce a decrease in rugosity and a surface smoothing on the outer margin of the reef. These effects are proportional to the accessibility of the site.

Vertical distribution of two sympatric labrid fishes in the Western Mediterranean and Eastern Atlantic rocky subtidal: local shore topography does matter

Changes in the shore topography (e.g. slope) occur at a scale of hundreds of meters in several locations in the Lusitanian and the Mediterranean Sea provinces. We tested whether differences in the bottom inclination might affect the vertical distribution patterns of two sympatric coastal labrid fishes, the rainbow wrasse Coris julis and the ornate wrasse Thalassoma pavo. Visual censuses were used to determine the distribution and abundance of these labrid species in high (‡30 ) and low (£3 ) slope rocky substrates covered by brown macroalgae and at two different depths (shallow, 4–7 m, and deep 14–20 m). Pectoral fin aspect ratio was used as an estimate of swimming performance to potentiall…

RESULTS OF DIFFERENT ANTHROPIC USES ON THE STRUCTURE OF VERMETID REEFS

The biogenic vermetid reef is a key habitat of coastal ecosystems that modifies the shoreline morphology and increases the local biodiversity. Despite its ecological relevance, rarely it is subjected to an accurate management and is often exposed to several human activities. This study aims to distinguish between the effects of different typologies of anthropic uses on the physical structure of the vermetid reef. A comparison between totally protected, partially protected and strongly anthropized reefs has been done and two variables have been analysed: the substratum complexity and the density of reef-building organism. Both the variables show higher values in totally and partially protect…

Scuba diver behaviour and its effects on the biota of a Mediterranean marine protected area

The effects of diving activity in different Mediterranean subtidal habitats are scarcely known. This study evaluates diver behaviour (for example time spent in each habitat), use (contacts made with the substrate) and immediate effects of diver contact on benthic species in a marine protected area (MPA) in Sicily. Over a two-year period, intentions of 105 divers were observed within seven subtidal habitats: algae on horizontal substrate, algae on vertical substrate, Posidonia oceanica, encrusted walls, caves, sand and pebbles. Divers selected a habitat in proportion to its availability along the scuba trail. On average, each diver made 2.52 contacts every seven minutes, and no differences w…

Hiding behaviour ofOxynoe olivacea(Mollusca: Opisthobranchia: Sacoglossa) in the invasive seaweedCaulerpa taxifolia

The occurrence of the invasive seaweed Caulerpa taxifolia in the Straits of Messina (Italy) provides an excellent opportunity to examine the spatial and temporal patterns of abundance of the endemic Mediterranean sacoglossan Oxynoe olivacea. Densities of this species were recorded in March, June and October 2000 on three different habitats: the underside of boulders (UNB), the upper side of boulders (UPB), and the surface of concrete blocks (CB). Results showed that in March, O. olivacea was consistently more abundant on UNB whereas in June it was present exclusively on CB. The density of O. olivacea was similar in the three habitats in October. The hiding behaviour of O. olivacea and its s…

Temporal variation of benthic assemblages in a Mediterranean MPA.

Drawing the Line at Neglected Marine Ecosystems: Ecology of Vermetid Reefs in a Changing Ocean

Vermetid mollusks form reefs that protect coasts from erosion, regulate sediment transport, serve as carbon sinks, and provide habitat for many fish and invertebrates. This biogenic habitat is found in tropical, sub-tropical, and warmtemperate coastal areas, such as Bermuda, oceanic islands in Brazil, and Hawaii, several locations within the Caribbean and the Mediterranean. These reefs are functionally similar to tropical coral fringing reefs but are built by gregarious vermetid gastropods cemented by a crustose coralline algal species, which probably triggers their settlement. Some descriptive studies in different regions worldwide and comparisons among tropical and Mediterranean reefs con…

Decreasing in patch-size of Cystoseira forests reduces the diversity of their associated molluscan assemblage in Mediterranean rocky reefs

Abstract Canopy-forming seaweeds of the genus Cystoseira (Fucales, Phaeophyceae) form diverse and productive habitats along temperate rocky coasts of the Mediterranean Sea. During the last decade, Cystoseira forests have retracted their range considerably due to many interacting environmental, biological and anthropogenic pressures. We investigated how reducing in patch-size of C. montagnei affects their associated molluscan communities at the shallow northwest rocky shores of Palermo (Sicily, Italy). Molluscs were sampled from the fronds of individual thalli, clumps of 3 and 5 thalli of C. montagnei over an annual vegetative cycle (May–September) in two sites within the Marine Protected Ar…

Unmanned aerial vehicle technology to assess the state of threatened biogenic formations: The vermetid reefs of mediterranean intertidal rocky coasts

Abstract Vermetid bioconstructions are biogenic formations, built by sessile gastropod molluscs belonging to the family Vermetidae worldwide distributed, occurring in the intertidal and upper subtidal in the rocky shores. In the Mediterranean basin, they occur in complex and tridimensional structures that enhance the local biodiversity, allowing to qualify the structuring species as ecosystem engineers. Due to their ecological relevance and considerable extension along the coasts, we assessed their structural complexity using unmanned aerial vehicle (UAV) technology, as tool of littoral cartography analysis of these bioconstructions, and plaster hemispheres dissolution as a descriptor index…

LA DIMENSIONE FRATTALE DEI REEF A VERMETI

Fractal geometry can be an useful tool to describe the structural complexity of a vermetid reef. Using fractal analysis of small surfaces, the fractal dimension for the outer rim of some vermetid reefs can be established. A positive correlation between fractal values and the density of Dendropoma petraeum is evident.

Dendropoma lower intertidal reef formations and their palaeoclimatological significance, NW Sicily

Abstract Most carbonate rocky shores of NW Sicily are marked by a coalescence of shells of the gastropod Dendropoma in a construction that is variably developed as a response to wave impact. Here, we review all the available information on these constructions and find that the fossil reefs are reliable sea-level indicators. The thickness of the reef samples never exceeds 30–40 cm below sea-level, whereas all 14 C dates fall within a range of few centuries. Some small fragments ejected by violent sea storms date back to 2500 years cal BP. No samples older than 6200 years cal BP have been detected so far. The present distribution of Mediterranean vermetid platforms should result from a northw…

Effects of fish feeding by snorkellers on the density and size distribution of fishes in a Mediterranean marine protected area

Although there is a great deal of evidence to show that supplementary feeding by humans in terrestrial environments causes pronounced changes in the distribution and behaviour of wild animals, at present very little is known about the potential for such effects on marine fish. This study evaluated the consequences of feeding by snorkellers on fish assemblages in the no-take area of the Ustica Island marine protected area (MPA; western Mediterranean) by (1) determining if reef fish assemblage structure is affected in space and time by tourists feeding the fish; (2) assessing the effects of feeding on the abundance of the most common fish species; and (3) assessing the effects of feeding on t…

DISTRIBUTION AND CONSERVATION NEEDS OF A NEGLECTED ECOSYSTEM: THE MEDITERRANEAN VERMETID REEF

Vermetid reefs are a key intertidal habitat in the Mediterranean. Despite recent evidence of local extinction in the Eastern Mediterranean, their role as habitat engineers and the high numbers of ecosystem services they provide, vermetid reefs are among the least known marine habitats of the Mediterranean. Here we present a literature-based study to assess for the first time their distribution inside the basin and provide evidence of a general lack of protection at Mediterranean scale.

Assessing vermetid reefs as indicators of past sea levels in the Mediterranean

Abstract The endemic Mediterranean reef building vermetid gastropods Dendropoma petraeum complex (Dendropoma spp) and Vermetus triquetrus develop bio-constructions (rims) on rocky shorelines at about Mean Sea Level (MSL) and are therefore commonly used as relative sea-level (RSL) markers. In this study, we use elevations and age data of vermetid reefs to (1) re-assess the vertical uncertainties of these biological RSL indicators, and (2) evaluate the vertical growth rates along a Mediterranean east-west transect, in attempt to explain the differences found in both growth rates and uncertainties. In Israel, Differential Global Positioning System (DGPS) and laser measurements relative to the …

The invasive seaweed Asparagopsis taxiformis erodes the habitat structure and biodiversity of native algal forests in the Mediterranean Sea

Abstract Invasive seaweeds are listed among the most relevant threats to marine ecosystems worldwide. Biodiversity hotspots, such as the Mediterranean Sea, are facing multiple invasions and are expected to be severely affected by the introduction of new non-native seaweeds in the near future. In this study, we evaluated the consequences of the shift from the native Ericaria brachycarpa to the invasive Asparagopsis taxiformis habitat on the shallow rocky shores of Favignana Island (Egadi Islands, MPA, Sicily, Italy). We compared algal biomass and species composition and structure of the associated epifaunal assemblages in homogenous and mixed stands of E. brachycarpa and A. taxiformis. The r…

Boat anchoring on Posidonia oceanica beds in a marine protected area (Italy, western Mediterranean): effect of anchor types in different anchoring stages

Seagrasses worldwide are noted for suffering from mechanical damage caused by boat anchoring. This is particularly so in sites highly frequented by boaters (marine protected areas or coastal urbanised areas). In the last decades, different strategies have been put into practice to reduce such impacts on seagrasses (i.e. by anchoring bans or by deploying boat moorings), More recently, in consideration that few marine protected area (MPA) management bodies or local administrations have the resources to enforce their anchorage regulations, the self-regulatory approach based on education and information of boaters has been preferred in several cases. At present, however, very little is known on…

Effect of algal architecture on associated fauna: some evidence from phytal molluscs

In the southern Mediterranean Sea, replicate samples of six common upper-infralittoral algae (Cystoseira barbatula, Cystoseira spinosa, Sargassum vulgare, Halopteris scoparia, Dictyota fasciola, and Dictyota dichotoma) were collected with the major goal of investigating the composition and structure of molluscan assemblages between the algal species. In order to measure the habitat architecture of the six algal species and relate this to the molluscan assemblages, several structural attributes were calculated on each individual plant. There were differences in architectural attributes between the six algal species, with data recorded for S. vulgare and H. scoparia more similar to data for C…

Short-term effect of human trampling on the upper infralittoral macroalgae of Ustica Island MPA (western Mediterranean, Italy)

The short-term response of Mediterranean upper infralittoral macroalgal species to experimental human trampling was investigated. Disturbances of six different intensities were applied within the integral reserve of the Ustica Island marine protected area (Italy, Mediterranean Sea). The dominant macroalgal species Cystoseira brachicarpa v. balearica and Dictyota mediterranea were strongly affected by human trampling. Higher levels of disturbance significantly affected both algal percentage cover and canopy at an increasing rate. Three months after trampling, for both variables it was highlighted that the algal recovery from disturbance was incomplete, being significantly different among tra…

Density and distribution patterns of the endangered species Pinna nobilis within the harbour bay of Favignana (Egadi Islands MPA)

The fan shell P. nobilis (Linnaeus, 1758) is the largest marine bivalve in the Mediterranean Sea which acts as ecosystem engineer, offering an adequate substratum to several associated benthic species. P. nobilis is threatened by the reduction and loss of its natural habitat and by increased anthropogenic inputs into coastal waters. The knowledge on the population of this species are scarce, especially as concerns Sicily and its coasts. This study focused on the density of population, spatial distribution, level of burial and orientation of the population of P. nobilis in the harbour area of Favignana island (western coast of Sicily, Italy). The fan shell surveys were carried out by SCUBA d…

Temporal dynamic of biofilms enhances the settlement of the central-Mediterranean reef-builder Dendropoma cristatum (Biondi, 1859).

Abstract Research on marine invertebrate settlement provides baseline knowledge for restoration technique implementation, especially for biogenic engineers with limited dispersion ability. Previously, we determined that the maturity of a biofilm strongly enhances the settlement of the vermetid reef-builder Dendropoma cristatum. To elucidate settlement-related biofilm features, here we analyse the structure and composition of marine biofilms over time, through microscopic observations, eukaryotic and prokaryotic fingerprinting analyses and 16S rDNA Illumina sequencing. The vermetid settlement temporal increase matched with the higher biofilm coverage on the substratum and the reduction of th…

REMOTELY PILOTED AIRCRAFT SYSTEMS (RPAS) APPLICATION FOR STRUCTURE DESCRIPTION OF MEDITERRANEAN VERMETID REEFS

Vermetid gastropods are coastal habitat engineers which build biogenic platforms typical of intertidal rocky shores of central and south -east of the Mediterranean. These bioconstructions create a secondary habitat which increases resource availability and space for organisms, locally transforming the environment and modifying coastal geomorphology. Biological characteristics and physical structure of these bioconstructions are commonly studied by field-based sampling. Nevertheless, a lot of time is required to collect data over large areas of reef, field conditions can impair data collection and direct reef image interpretation may be a challenge due to their intertidal position. In this s…

Mediterranean Bioconstructions Along the Italian Coast

Marine bioconstructions are biodiversity-rich, three-dimensional biogenic structures, regulating key ecological functions of benthic ecosystems worldwide. Tropical coral reefs are outstanding for their beauty, diversity and complexity, but analogous types of bioconstructions are also present in temperate seas. The main bioconstructions in the Mediterranean Sea are represented by coralligenous formations, vermetid reefs, deep-sea cold-water corals, Lithophyllum byssoides trottoirs, coral banks formed by the shallow-water corals Cladocora caespitosa or Astroides calycularis, and sabellariid or serpulid worm reefs. Bioconstructions change the morphological and chemicophysical features of prima…

Variazioni temporali della struttura di taglia in popolazioni sfruttate di Haliotis tuberculata (Mollusca Gastropoda) nel Golfo di Sferracavallo (PA)

This study aims at evaluating the differences in size structure of population of H. tuberculata in the Gulf of Sferracavallo (northern Sicily) which experienced the co-occurrence of high exploitation and decrease of eutrophic conditions during the eighties and early nineties. Comparison of size structure showed significant differences between length frequency distributions of 1970-75s and 2002-2005, being the latter formed by smaller size green ormer.

Valutazione della componente bentonica di ipostrato in tre aree marine protette del Tirreno meridionale

Valutazione del comportamento dei subacquei in immersione nell’AMP ‘Isola di Ustica’.

IL PROGETTO GEBECSUD: UN APPROCCIO DI TIPO PAESAGGISTICO ALLA VALUTAZIONE DELLA QUALITÀ AMBIENTALE IN AREE MARINE COSTIERE

First assessment of the vermetid reefs along the coasts of Favignana Island (Southern Tyrrhenian Sea)

Intertidal vermetid reefs, particularly vulnerable to environmental changes and human activities, are now experiencing high mortality in several areas of the Mediterranean Sea. Since the increase of knowledge on this habitat is important for conservation purposes, we provide a first baseline assessment of the vermetid reefs along the coasts of the Favignana Island (Marine Protected Area “Egadi Islands”). Preliminary results showed the presence of a true reef, similar to a fringing reef, displaying at least three local patterns, distinguishable for width (from 2.3 to 15.5 m), height of the outer and of the inner margin (from 5.6 to 18 cm and from 8.3 to 26 cm, respectively) and number, width…

The Impact of Human Recreational Activities in Marine Protected Areas: What Lessons Should Be Learnt in the Mediterranean Sea?

. The aesthetic appeal of marine reserves and the facilities provided, together with the increased public awareness of nature, all contribute to creating massive tourism in MPAs. Human activities are being changed inside MPAs in two ways: humans as top predators are generally being removed, but in turn they could come back at great numbers as visitors. Many authors have studied the impact of visitors, and the results highlight that the consequences can be very substantial and may represent a severe threat to the overall diversity of marine communities. To date, the documented effects of human recreational activities on natural communities are restricted to assessing the consequences of tram…

A new marker for sea surface temperature trend during the last centuries in temperate areas: Vermetid reef

The presence of Vermetid reefs in temperate waters, their diffusion in the Mediterranean Sea, and the possibility of performing 14 C ages allowed the use of Vermetids as an indicator of sea level changes. We present new data on sea climate trend fluctuations that could be interpreted as Sea Surface Temperature (SST) variations, recorded on Vermetid (Dendropoma petraeum) reefs, by means of isotopic analysis. The isotopic records show positive values of the d 18 O relative to present-day values in the period between 1600 and 1850 AD; this deviation occurs in association with the climatic cooling event known as Little Ice Age (LIA). Subsequently, we can observe the warming trend that character…

Relazione tra le densità di Dendropoma petraeum e la microtopografia del reef a vermeti”

Biogenic habitat shifts under long-term ocean acidification show nonlinear community responses and unbalanced functions of associated invertebrates

Este artículo contiene 8 páginas, 4 figuras.

Preliminary evaluation of a small marina impact on a sublittoral benthic assemblage.

Latitudinal- and local-scale variations in a rocky intertidal interaction web

Natural assemblages are structured by a complex combination of positive and negative interactions, and the relative importance of each interaction can vary across spatial scales. By using a simple interaction web (barnacles-grazers-microphytobenthos) in a rocky intertidal system, we tested the hypothesis that the relative strength of positive and negative interactions would vary as a function of different environmental stress between 2 latitudinal levels and local environmental conditions. We manipulated the cover of barnacles and the presence of limpets at 2 sites in northern and southern Italy and non-destructively examined the response of microphyto - benthos (MPB) (photosynthetic biomas…

Do invasive macroalgae influence biodiversity and abundance of Amphipod Crustaceans ?

Amphipods are an essential element of the food web in marine coastal environments, and represent a good indicator of the health of the ecosystems. The composition of amphipod assemblage is often linked to algal coverage, in which the benthic species find refuge from predators and a great availability of food resources. Within the management and conservation of natural environments, one of the main problems is currently represented by the invasion of non-indigenous species, which modifies native communities. This research compares the amphipod fauna associated with Asparagopsis taxiformis (Delile) Trevisan de Saint-Léon, a non-indigenous red macroalga widely distributed along the west coast …

Integrating natural capital assessment and marine spatial planning: A case study in the Mediterranean sea

Abstract Marine and coastal ecosystems are among the most productive environments in the world and their stocks of natural capital offer a bundle of vital ecosystem services. Anthropogenic pressure seriously threatens health and long-term sustainability of marine environments. For these reasons, integrated approaches capable of combining ecological and socio-economic aspects are needed to achieve nature conservation and sustainability targets. In this study, the value of natural capital of the Egadi Islands Marine Protected Area (EI-MPA) was assessed through a biophysical and trophodynamic environmental accounting model. The emergy value of both autotrophic and heterotrophic natural capital…

Different densities of the limpet populations in a Sicilian MPA: do enforcement or accessibility matter?

The invasive Asparagopsis taxiformis hosts a low diverse and less trophic structured molluscan assemblage compared with the native Ericaria brachycarpa

Abstract Invasive seaweeds threaten biodiversity and socio-economics values of worldwide marine ecosystems. Understanding to what extent invasive seaweeds can modify local biodiversity is one of the main priorities in conservation ecology. We compared the molluscan assemblage of the invasive Asparagopsis taxiformis with that of the native Ericaria brachycarpa and explore if variation in the molluscan assemblage diversity was related to the substrate attributes (biomass, and thallus, canopy, and interstitial volumes) of the algae. Results showed that A. taxiformis harboured lower diversity and trophic structure of the molluscan assemblage compared to E. brachycarpa. Biomass was the variable …

Studio degli effetti di un impatto sui reef a vermeti mediante metodi di ecologia del paesaggio.

Compatibilità ambientale delle attività inerenti il completamento delle opere marittime esistenti per la messa in sicurezza del porto di Isola delle Femmine ai sensi dell’art. 5 della l.r. 21/98.

Effetti indiretti della pasturazione dei pesci per scopi ricreativi.

Diversità strutturale e funzionale di popolamenti ittici costieri: uno sudio sperimentale per valutare la convergenza evolutiva ed ecologica in due regioni a clima mediterraneo.

A posteriori application of the ‘Marep’ to the zonation of the Egadi Islands.

CONSERVATION NEEDS FOR THE VERMETID REEFS IN THE MEDITERRANEAN SEA

Vermetid reefs are intertidal bioconstructions typical of many subtropical and temperate coastal areas worldwide. Distributed in the warmest waters of the Mediterranean Sea, the reefs are built by the vermetid gastropod Dendropoma petraeum and the coralline alga Neogoniolithon brassica-florida, two species included in the annexes of the Berna Convention. Vermetid reefs provide a wide set of ecosystem services, such as coastal protection from erosion, regulation of sediment transport and accumulation, serving as carbon deposit and increasing biodiversity at the intertidal level. Despite its vulnerability to several threats, such as pollution, spread of invasive species, ocean acidification a…

Warming-related shifts in the distribution of two competing coastal wrasses

13 páginas, 5 figuras , 1 tabla, 1 apéndice con tres tablas y una figura

Vertical distribution of two sympatric labrid fishes in the Western Mediterranean and Eastern Atlantic rocky subtidal: local shore topography does matter

Changes in the shore topography (e.g. slope) occur at a scale of hundreds of meters in several locations in the Lusitanian and the Mediterranean Sea provinces. We tested whether differences in the bottom inclination might affect the vertical distribution patterns of two sympatric coastal labrid fishes, the rainbow wrasse Coris julis and the ornate wrasse Thalassoma pavo. Visual censuses were used to determine the distribution and abundance of these labrid species in high (‡30� ) and low (£3� ) slope rocky substrates covered by brown macroalgae and at two different depths (shallow, 4‐7 m, and deep 14‐20 m). Pectoral fin aspect ratio was used as an estimate of swimming performance to potentia…

Dataset from: Small-scale patches of detritus as habitat for invertebrates within a Zostera noltei meadow

This dataset is related to "Small-scale patches of detritus as habitat for invertebrates within a Zostera noltei meadow" (Valentina Costa, Renato Chemello, Davide Iaciofano, Sabrina Lo Brutto, Francesca Rossi)

Seawater carbonate chemistry and biogenic habitat shifts under long-term ocean acidification

Experiments have shown that increasing dissolved CO2 concentrations (i.e. Ocean Acidification, OA) in marine ecosystems may act as nutrient for primary producers (e.g. fleshy algae) or a stressor for calcifying species (e.g., coralline algae, corals, molluscs). For the first time, rapid habitat dominance shifts and altered competitive replacement from a reef-forming to a non-reef-forming biogenic habitat were documented over one-year exposure to low pH/high CO2 through a transplant experiment off Vulcano Island CO2 seeps (NE Sicily, Italy). Ocean acidification decreased vermetid reefs complexity via a reduction in the reef-building species density, boosted canopy macroalgae and led to chang…

Ocean acidification impairs vermetid reef recruitment

Vermetids form reefs in sub-tropical and warm-temperate waters that protect coasts from erosion, regulate sediment transport and accumulation, serve as carbon sinks and provide habitat for other species. The gastropods that form these reefs brood encapsulated larvae; they are threatened by rapid environmental changes since their ability to disperse is very limited. We used transplant experiments along a natural CO2 gradient to assess ocean acidification effects on the reef-building gastropod Dendropoma petraeum. We found that although D. petraeum were able to reproduce and brood at elevated levels of CO2, recruitment success was adversely affected. Long-term exposure to acidified conditions…

Struttura di popolazione di Haliotis tuberculata in aree soggette a diversi livelli di protezione

This study aims at evaluating the current status of H. tuberculata stocks in exploited areas of western Sicily. The density of the green ormer was slightly greater in unexploited areas although differences between harvested and not harvested areas was not statistically significant. Moreover, analyses showed that length frequencies varied between harvested and not harvested areas.