References of "Sturaro, Nicolas"
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See detailMultiscale variability of amphipod assemblages in Posidonia oceanica meadows
Sturaro, Nicolas ULg; Lepoint, Gilles ULg; Vermeulen, Simon et al

in Journal of Sea Research (in press)

The study of spatial patterns is of ecological importance in order to understand the causes of the distribution and abundance of organisms, and it also provides valuable basis for management and ... [more ▼]

The study of spatial patterns is of ecological importance in order to understand the causes of the distribution and abundance of organisms, and it also provides valuable basis for management and conservation. Amphipod crustaceans are key organisms in seagrass ecosystems. However, little attention has been paid to the spatial scales at which amphipod assemblages may vary. We examined variability patterns of amphipod populations inhabiting Posidonia oceanica meadows, over spatial scales spanning four orders of magnitude (1 to 1000 metres) and for two consecutive years. This study reports the scales that contributed most to spatial variation of amphipod assemblages and explores the potential processes of the observed patterns, with particular emphasis on habitat features. The number of species, the diversity and the density of some species, exhibited high variation across years. Most species showed the highest spatial variation in density and biomass at small scales (~1 and 10 m). Based on density data, the structure of amphipod assemblages did not differ at any scales investigated. The patchiness that occurred at small scales may have been only weakly related to habitat features. Instead, we postulated that behavioural processes of amphipods were likely good explanatory factors. Although, the small scale spatial variability can be an important feature of amphipod assemblages in P. oceanica meadows, many patterns probably remained undetected as they may occur at scales smaller than those investigated. [less ▲]

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See detailSeagrass amphipod assemblages in a Mediterranean marine protected area: a multiscale approach
Sturaro, Nicolas ULg; Lepoint, Gilles ULg; Pérez-Perera, Amanda et al

in Marine Ecology. Progress Series (2014), 506

Marine protected areas (MPAs) are a key tool for conservation purposes, but few studies have assessed the responses of small macrozoobenthic assemblages to different protection levels in the Mediterranean ... [more ▼]

Marine protected areas (MPAs) are a key tool for conservation purposes, but few studies have assessed the responses of small macrozoobenthic assemblages to different protection levels in the Mediterranean Sea. In this study, we used a hierarchical sampling design spanning three orders of magnitude (1-10-100 metres) to investigate whether a marine protected area exerts an effect on amphipod assemblages associated with Posidonia oceanica meadows. This study reports spatial and temporal variability patterns of amphipod assemblages in four different protection levels and discusses potential confounding effects, such as habitat features. The structure of amphipod assemblages based on density data was patchy at all spatial scales investigated, but differed markedly among protection levels. Among outstanding points, multiscale analyses showed that lower densities and/or biomasses of several taxa occurred within fully protected and external areas in comparison with partially protected areas (PPAs). Furthermore, Posidonia oceanica meadow features (shoot density, leaf and epiphyte biomasses, coefficient A and litter biomass) accounted for only a low proportion of the total variability. We can consequently infer that the observed patchiness is likely to occur for multiple and interconnected reasons, ranging from the ecological and behavioural traits of amphipod species to protection-dependent processes (e.g. fish predation). Long term multiscale spatial and temporal monitoring, as well as experimental manipulations, are clearly needed to fully understand the effects of protection on macrozoobenthic assemblages. [less ▲]

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See detailProtection effects or natural variability? The case of seagrass amphipods
Sturaro, Nicolas ULg; Lepoint, Gilles ULg; Pérez-Perera, Amanda et al

Conference (2013, October)

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See detailSocio-ecological study of recreational boating in a Mediterranean marine protected area
Pérez-Perera, Amanda; Panzalis, Pier; Navone, Augusto et al

Poster (2012, November)

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See detailA new species of Caprella (Crustacea: Amphipoda) from the Mediterranean Sea
Sturaro, Nicolas ULg; Guerra-García, José Manuel

in Helgoland Marine Research (2012)

A new caprellid amphipod, Caprella tavolarensis n. sp., is described based on specimens collected from a Posidonia oceanica seagrass meadow at the Tavolara- Punta Coda Cavallo Marine Protected Area ... [more ▼]

A new caprellid amphipod, Caprella tavolarensis n. sp., is described based on specimens collected from a Posidonia oceanica seagrass meadow at the Tavolara- Punta Coda Cavallo Marine Protected Area (Sardinia, Mediterranean Sea). The species is close to Caprella liparotensis, but can be clearly distinguished by smaller size, presence of a short rostrum, body elongate and dorsally smooth, absence of serrate carina on the basis of gnathopod 2 and pereopods, mouthparts scarcely setose, absence of Wne setae on peduncle of antenna 1 and absence of swimming setae on antenna 2. The number of caprellid species reported from the Mediterranean Sea has increased from 23 (1993) to 41 (2010), consequently, further taxonomical studies should be addressed to properly estimate the total amphipod diversity in the Mediterranean Sea. [less ▲]

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See detailPotential early indicators of anthropogenically derived nutrients : a multiscale stable isotope analysis
Vermeulen, Simon ULg; Sturaro, Nicolas ULg; Gobert, Sylvie ULg et al

in Marine Ecology. Progress Series (2011), 422

Increasing human pressure along Mediterranean coastlines raises the need to define sensitive bioindicators that provide an early response to nutrient enrichment. We performed multiscale carbon and ... [more ▼]

Increasing human pressure along Mediterranean coastlines raises the need to define sensitive bioindicators that provide an early response to nutrient enrichment. We performed multiscale carbon and nitrogen stable isotope analyses on the limpet Patella caerulea, the snail Monodonta turbinata, epilithic biofilms, and the macroalga Rissoella verruculosa inhabiting the rocky midlittoral zone. Samples were seasonally collected in 2006 from 5 sites exposed to a range of anthropogenic discharges in the Revellata Bay area and in Marseille harbour (France). All bioindicators exhibited strongly elevated δ15N values at impacted sites compared to pristine ones, which revealed the biological availability of anthropogenically derived nutrients. Only epilithic biofilms tended to show both the occurrence of nutrient pulses during the tourist season and a δ13C response at impacted sites. In contrast to macroalgae, which exhibited a somewhat equivocal signal, gastropods and especially M. turbinata provided the best time-integrated picture of the graduated exposure of the 5 sites to anthropogenic impact. Results also showed first evidence of large isotopic variability at a scale of tens of metres, close to that found at the kilometre scale. The intra- and interspecific isotopic variability in gastropods may be explained by the patchiness of resources and specific morphological and behavioural features, but these factors do not greatly hamper their potential as early bioindicators of wastewater disturbances. [less ▲]

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See detailDistribution patterns of Caprella tavolarensis (Crustacea: Amphipoda) in the Tavolara-Punta Coda Cavallo Marine Protected Area.
Sturaro, Nicolas ULg; Gobert, Sylvie ULg; Lepoint, Gilles ULg et al

in Biologia Marina Mediterranea (2011), 18(1), 290-291

Distribution patterns of Caprella tavolarensis was investigated at the tavolara-punta Coda Cavallo Marine protected area. results revealed that C. tavolarensis abundance may exhibit spatial patterns ... [more ▼]

Distribution patterns of Caprella tavolarensis was investigated at the tavolara-punta Coda Cavallo Marine protected area. results revealed that C. tavolarensis abundance may exhibit spatial patterns associated with the protection status of the zones, highlighting the importance of totally protected areas in species conservation and management. [less ▲]

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See detailTop-down role of fish predators in structuring amphipod community associated to Posidonia oceanica seagrass meadows
Sturaro, Nicolas ULg; Lepoint, Gilles ULg; Panzalis, Pier et al

Poster (2010, October)

Despite the major ecological importance of Posidonia oceanica seagrass meadows in the Mediterranean Sea, little attention has been given to community structuring forces by predators in this ecosystem. To ... [more ▼]

Despite the major ecological importance of Posidonia oceanica seagrass meadows in the Mediterranean Sea, little attention has been given to community structuring forces by predators in this ecosystem. To better understand the mechanisms by which fishes affect amphipod community structure associated to P. oceanica beds, experimental manipulations of predation intensity (enclosure and exclusion cages) were set up in the Tavolara-Punta Coda Cavallo Marine Protected Area (Sardinia, NW Mediterranean). In totally protected area, where high abundance of predatory fishes is recorded, we have performed exclusion experiment. Total amphipod abundance increased at the end of the experiment, but diversity and specific composition were unaffected. At the species taxonomic level, significant increase in abundance between treatments appeared only for Caprella acanthifera. In partially protected area, where fish abundance is lower and amphipod abundance higher, individuals of the carnivorous fish Coris julis (Labridae) were enclosed in cages to provide an estimate of the potential for this species to impact on amphipod community. There was a small but measurable effect on amphipod abundance between enclosures and unmanipulated controls. A few dominant amphipod species responded to fish predation by significant decrease in abundance. These results suggest that fish predation may determine the relative abundances in the community of some amphipod species and to some degree, through an untested link with habitat complexity, determine the spatial distribution of amphipod abundance within P. oceanica beds. Moreover, patterns observed at the species level, suggest parallel complex interactions probably mainly related to ecological behaviour of amphipod species. [less ▲]

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See detailThe role of fish predation in the structure of amphipod community associated with Posidonia oceanica seagrass meadows
Sturaro, Nicolas ULg; Lepoint, Gilles ULg; Panzalis, Pier et al

Conference (2010, September)

Despite the major ecological importance of Posidonia oceanica seagrass meadows in the Mediterranean Sea, little attention has been given to community structuring forces by predators in this ecosystem. To ... [more ▼]

Despite the major ecological importance of Posidonia oceanica seagrass meadows in the Mediterranean Sea, little attention has been given to community structuring forces by predators in this ecosystem. To better understand the mechanisms by which fishes affect amphipod community structure associated to P. oceanica beds, experimental manipulations of predation intensity (enclosure and exclusion cages) were set up in the Tavolara-Punta Coda Cavallo Marine Protected Area (Sardinia, NW Mediterranean). In totally protected area, where high abundance of predatory fishes is recorded, we have performed exclusion experiment. Total amphipod abundance increased at the end of the experiment, but diversity and specific composition were unaffected. At the species taxonomic level, significant increase in abundance between treatments appeared only for Caprella acanthifera. In partially protected area, where fish abundance is lower and amphipod abundance higher, individuals of the carnivorous fish Coris julis (Labridae) were enclosed in cages to provide an estimate of the potential for this species to impact on amphipod community. There was a small but measurable effect on amphipod abundance between enclosures and unmanipulated controls. A few dominant amphipod species responded to fish predation by significant decrease in abundance. These results suggest that fish predation may determine the relative abundances in the community of some amphipod species and to some degree, through an untested link with habitat complexity, determine the spatial distribution of amphipod abundance within P. oceanica beds. Moreover, patterns observed at the species level, suggest parallel complex interactions probably mainly related to ecological behaviour of amphipod species. [less ▲]

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See detailTrophic diversity of idoteids (Crustacea, Isopoda) inhabiting the Posidonia oceanica litter
Sturaro, Nicolas ULg; Caut, Stéphane; Gobert, Sylvie ULg et al

in Marine Biology (2010), 157(2), 237-247

The coexistence of three idoteid species in Posidonia oceanica litter raises the question of trophic diversity and their role in the litter degradation process. Hence, diet composition of Idotea balthica ... [more ▼]

The coexistence of three idoteid species in Posidonia oceanica litter raises the question of trophic diversity and their role in the litter degradation process. Hence, diet composition of Idotea balthica, Idotea hectica and Cleantis prismatica was studied using a combination of gut contents and stable isotopes analysis. Gut content observations indicate that P. oceanica dead leaves are an important part of the ingested food for the three species, although their tissues are constituted of only a small to medium fraction of P. oceanica carbon. Our results also underlined the potential role of these species in the degradation of P. oceanica litter by mechanically fragmenting the litter and by assimilating a small to medium fraction of carbon. Moreover, we showed that there were considerable inter- and intra-specific differences in diet composition. Diet differed between juveniles and adults for I. balthica. Crustaceans are an important food source for adults of I. balthica, while I. hectica indicated a major contribution of algal material. C. prismatica showed an intermediate diet. This trophic diversity is probably one of the factors allowing these species to coexist in the same biotope. [less ▲]

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See detailSampling methods for amphipods of Posidonia oceanica meadows: a comparative study
Michel, Loïc ULg; Lepoint, Gilles ULg; Dauby, Patrick ULg et al

in Crustaceana (2010), 83(1), 39-47

Efficient sampling of amphipod crustaceans associated with Posidonia oceanica (L.) Delile meadows is difficult, due to their complex community structure and to the heterogeneity of the meadows. Here we ... [more ▼]

Efficient sampling of amphipod crustaceans associated with Posidonia oceanica (L.) Delile meadows is difficult, due to their complex community structure and to the heterogeneity of the meadows. Here we compare three sampling techniques: the hand-towed net, the air-lift, and light traps. Each of the methods shows specific advantages and disadvantages, hence the most important feature to consider in the choice of the method would be its adequacy with regard to the study purpose. Moreover, the most accurate way to sample amphipods from P. oceanica meadows could be to combine several methods, keeping in mind their respective strengths and weaknesses, and to adapt the sampling protocol to the aims of the study at issue. [less ▲]

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See detailMulti-scale spatial variability of amphipod assemblages from the foliar stratum of the Posidonia oceanica (L.) Delile meadow
Sturaro, Nicolas ULg; Lepoint, Gilles ULg; Michel, Loïc ULg et al

Conference (2008, October)

Studying spatial patterns is of ecological importance in order to understand the causes of the distribution and abundance of organisms, and it also provides valuable basis for management and conservation ... [more ▼]

Studying spatial patterns is of ecological importance in order to understand the causes of the distribution and abundance of organisms, and it also provides valuable basis for management and conservation. In the Mediterranean coastal zone, the Posidonia oceanica seagrass meadows constitute one of the dominant ecosystems and are an important habitat for vagile invertebrates. Among these, amphipods comprise a large number of species, with considerable abundance and biomass, as well as being an important trophic resource for fish populations. Until now, little attention has been given to the horizontal variability at different spatial scales of amphipod assemblages associated with P. oceanica meadows. A hierarchical sampling design, spanning three orders of magnitude (from 1 to 100s of metres) was elaborated. Sampling was undertaken in March 2007 in the meadows of Calvi Bay (NW Corsica), at depths ranging from 10 to 13 m, using a suction sampler. Our results indicated an important horizontal variability of the studied assemblage, and this at different spatial scales. In addition, these results tend to show that the small scale (~ 1 m and ~ 10 m) influenced abundance, while the medium-scale (~ 100 m) influenced diversity. Some potential causes of the observed patterns are discussed. These results emphasize the importance of considering different spatial scales in the study of the vagile invertebrates associated with P. oceanica meadows. [less ▲]

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See detailApproche préliminaire de la variabilité spatiale multiéchelle de la structure de la communauté de crustacés amphipodes associée aux herbiers à Posidonia oceanica
Sturaro, Nicolas ULg

Master of advanced studies dissertation (2007)

L’objectif de ce travail était d’analyser la variabilité spatiale de la structure de la communauté d’amphipodes associée à la strate foliaire de l’herbier à Posidonia oceanica à différentes échelles, à ... [more ▼]

L’objectif de ce travail était d’analyser la variabilité spatiale de la structure de la communauté d’amphipodes associée à la strate foliaire de l’herbier à Posidonia oceanica à différentes échelles, à savoir l’échelle ~ 1 m, l’échelle ~ 10 m et l’échelle ~ 100 m. Trois cadres permanents placés à une profondeur de 12-13 m et séparés horizontalement d’une distance de 10 et 100 m, ont été échantillonnés en mars 2007 à l’aide d’une suceuse à air comprimé. Neuf prélèvements on été analysés. L’analyse des échantillons fait apparaître que la communauté d’amphipodes est abondante, riche en espèces et montre une diversité considérée comme moyenne. D’autre part, cette communauté est dominée par quelques espèces seulement, à savoir Apherusa chiereghinii, Aora spinicornis, Amphilochus neapolitanus et le taxon Apherusa sp., représente à eux quatre 83,4 % du total des individus récoltés. L’abondance relative des taxons dominants se révèle relativement identique. La méthode de prélèvement utilisée à savoir la suceuse à air comprimé s’avère efficace vu le nombre important d’amphipodes récoltés (jusqu’à 97 individus pour une surface de 0,129 m2 et le faible taux d’organismes endommagés (3,7 % du total des individus). L’analyse des résultats obtenus pour les caractéristiques structurelles de la communauté montre qu’il existe une variabilité spatiale importante au sein de la communauté d’amphipodes, et ceci aux différentes échelles étudiées. Ces résultats démontrent également que certaines échelles influencent les caractéristiques de la communauté plus que d’autres. La petite échelle spatiale (~ 1m et ~ 10 m) a tendance à influencer l’abondance des amphipodes, alors que la moyenne échelle spatiale (~ 100 m) a un effet sur la richesse spécifique et la diversité de la communauté étudiée. Les résultats obtenus dans ce travail concernant l’abondance des amphipodes entre les différents prélèvements, les valeurs de l’indice de dispersion I (toujours supérieures à 1) et l’analyse multidimensionnelle suggèrent que cette communauté est caractérisée par une répartition spatiale irrégulière en taches (« patchiness »), à petite échelle (~ 1 m). La comparaison de l’abondance entre les cadres 1 et 2 montre aussi une différence significative. Cependant, pour ces deux échelles spatiales, aucune relation n’a pu être mise en évidence avec les caractéristiques de l’herbier (densité en faisceaux de posidonies et longueur maximale des feuilles). L’étude de l’échelle spatiale ~ 100 m montre qu’il existe des variations de la richesse spécifique et de la diversité de la communauté. Ces variations pourraient être expliquées par la présence d‘accumulations de litières plus importantes où la densité de l’herbier est plus faible. L’ensemble de ces résultats tente de suggérer qu’il est donc essentiel d’intégrer différentes échelles spatiales dans l’étude de la faune vagile de l’herbier à posidonies, en particulier celle des crustacés amphipodes. [less ▲]

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See detailNocturnal vertical migrations by amphipods of the Posidonia oceanica (L.) Delile foliar stratum : Importance of the litter cover
Michel, Loïc ULg; Sturaro, Nicolas ULg; Lepoint, Gilles ULg et al

Poster (2007, November)

In seagrass meadows, several groups of vagile invertebrates are well known to perform a nocturnal rise from the lower layers of the meadow to the foliar stratum. This vertical migration is generally ... [more ▼]

In seagrass meadows, several groups of vagile invertebrates are well known to perform a nocturnal rise from the lower layers of the meadow to the foliar stratum. This vertical migration is generally regarded as a defense mechanism against predation by diurnal fishes, as well as a mean to maximize the exploitation of trophic resources offered by the meadow. Here, we focused on the amphipods from a Mediterranean Posidonia oceanica meadow. We sampled the community present in the meadows of Calvi Bay (NW Corsica) using two different techniques (hand-towed net and litter collecting). Samples were taken at two seasons, during both night and daytime. Our results confirm the nocturnal rise to the foliar stratum. Combined to an analysis of the recent literature, they also tend to show that amphipods spend the daytime not in the matte itself, as it has been proposed in the past, but in the thin layer of Posidonia litter present at the interface between the foliar stratum and the root/rhizome system. This would emphasize the role of the litter cover in the complexity of the habitat within the meadow, and therefore in the vagile invertebrate community structure and the functioning of the whole meadow as an ecosystem. [less ▲]

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See detailTrophic diversity and potential role of detritivorous crustaceans in Posidonia oceanica litter
Sturaro, Nicolas ULg; Gobert, Sylvie ULg; Cox, Anne-Sophie et al

Conference (2006, June)

Detrivorous crustaceans are pivotal components of the trophic food webs and are found to be the main constituents of the macrofauna in Posidonia oceanica litter. The coexistence of many of these species ... [more ▼]

Detrivorous crustaceans are pivotal components of the trophic food webs and are found to be the main constituents of the macrofauna in Posidonia oceanica litter. The coexistence of many of these species in the same biotope raises the question of trophic diversity and of its role in litter degradation process. Diet composition of five common species of detrivorous crustaceans in P. oceanica litter (i.e. the gammarid amphipods Gammarella fusicola and Gammarus aequicauda and the isopods Idotea baltica, Idotea hectica and Zenobiana prismatica) were studied using a combination of gut content and stable isotopes analysis. Despite the common food supply (i.e. Posidonia dead leaf, Posidonia epiphytes or drift macroalgae), there were considerable interspecific differences in diet composition. Gut content observations indicate that P. oceanica leaf litter is an important part of the ingested food of all the species. Algae material (macroepiphytes and drift macroalgae) inhabiting the litter is mainly found in G. fusicola, I. hectica and I. baltica. I. baltica displays a high proportion of crustacean fragments. Isotope ratios showed that most of the species do not assimilate much of the ingested Posidonia. Application of a mixing model using isotopic values to estimate the contribution of the potential different food sources confirms this view. On one hand, the tissue of G. aequicauda could be constituted by more than 50 % of P. oceanica carbon. On the other hand, for the other species studied, P. oceanica represented a minor contribution (10 - 30 %), although it is a major component of the gut contents. This could imply that micro-organism (diatoms, bacteria and fungi) living on the Posidonia detritus is a major food source of detrivorous. Moreover, I. baltica, Z. prismatica and G. fusicola have a diversified diet composed mainly of algae. Crustaceans are an important food source for I. baltica. By contrast, I. hectica indicated a major contribution of algae material. Our results demonstrate the trophic diversity existing between the detrivorous crustaceans species in P. oceanica litter. This trophic diversity is probably one of the factors that allows these species to coexist in the same biotope. The results also underline the potential role of these species in the degradation of P. oceanica litter by fragmenting mechanically the Posidonia detritus and by assimilating directly Posidonia carbon and transferring it to higher trophic level (i.e. coastal fishes). Moreover, it allows us to think that micro-organisms (diatoms, bacteria and fungi) colonising leaf litter may constitute an important food source for litter fauna. [less ▲]

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See detailDiversité trophique des Idoteidae associés à l’herbier et à la litière de Posidonia oceanica (L.) Delile
Sturaro, Nicolas ULg

Master's dissertation (2005)

La diversité trophique de cinq espèces d’Idotéidés associées à l’herbier et à la litière de P. oceanica (L) Delile a été étudiée en utilisant la combinaison de deux méthodes: l’analyse des contenus ... [more ▼]

La diversité trophique de cinq espèces d’Idotéidés associées à l’herbier et à la litière de P. oceanica (L) Delile a été étudiée en utilisant la combinaison de deux méthodes: l’analyse des contenus digestifs et la mesure des rapports isotopiques du carbone et de l’azote. Les valeurs isotopiques ont été intégrées dans un «mixing model» permettant d’évaluer les contributions relatives de sources de nourritures potentielles aux régimes alimentaires des différentes espèces. Les spécimens ont été récoltés en mars 2004 et mars 2005 à trois stations de prélèvements de la baie de la Revellata (Calvi, Corse) dans l’herbier de posidonies et dans la litière composée d’accumulation de feuilles mortes, de pousses de posidonies et de macroalgues arrachées. Cinq espèces d’Idotéidés ont été trouvées durant cette étude, Idotea baltica étant l’espèce la plus abondante. I. baltica semble restreinte à la litière de posidonies. Par contre, I. hectica, seconde espèce en terme d’abondance, fréquente à la fois les accumulations de litière et l’herbier de posidonies. Le matériel a été caractérisé (tailles, sexes, phénotypes) et 98 tubes digestifs ont été analysés. Au total 20 % des tubes digestifs étaient vides. Les résultats montrent que les espèces I. baltica, I. hectica et Zenobiana prismatica récoltés dans la litière ingèrent principalement des algues arrachées, des crustacés de la litière et des feuilles mortes de posidonies. Les espèces I. hectica et Synisoma appendiculatum prélevées dans l’herbier préfèrent les algues épiphytes mais quelques fragments de feuilles de posidonies et des diatomées sont aussi présents. L’application d’un «mixing model» suggère que les algues photophiles et épiphytes contribuent pour la majeure partie du carbone assimilé chez ces espèces (gamme de 0 jusqu’à plus de 80 %). La part des crustacés est importante chez I. baltica, ce qui traduit une plus grande diversification du régime alimentaire chez cette espèce, tendance qui s’accentue avec l’âge des individus. I. hectica montre un comportement plus sélectif et dirigé vers la flore épiphyte ou les algues arrachées. Les feuilles mortes de P. oceanica n’interviennent que pour une très faible partie (maximum 15 %) du matériel assimilé, contribution largement inférieure à la contribution en tant que matériel ingéré. Ceci souligne que le rôle de ces espèces dans la dégradation de la litière de P. oceanica est principalement mécanique (i.e. fragmentation des particules) et que la microflore associée aux feuilles mortes constitue vraisemblablement une source alimentaire importante. C’est probablement l’hétérogénéité de l’habitat et la diversité trophique des Idotéidés qui permettent leur coexistence au sein des mêmes biotopes. [less ▲]

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