Ecología de Caulerpales

En la present tesis doctoral són estudiats els canvis en les comunitats bentòniques produïts per la substitució de praderies de Posidonia oceanica per algues invasores del gènere Caulerpa (Caulerpa racemosa y Caulerpa taxifolia) i la caulerpal establida Caulerpa prolifera. Les comunitats bentòniques canvien amb la presència de les caulerpals. Les principals diferències entre els quatre hàbitats són degudes a les diferents abundàncies que presenten les espècies coincidents tant per mol·lusc, decàpodes com poliquets. A més, la comunitat d’invertebrats té patrons estacionals diferents entre els quatre hàbitats (referits a abundància i diversitat de espècies). Les algues del gènere Caulerpa es caracteritzen per contenir caulerpenina com metabòlit secundari de defensa. La toxicitat de les caulerpals es veu reflectida en un increment de les defenses antioxidants dels organismes que hi viuen en hàbitats de Caulerpa (Coris julis i Bittium reticulatum), els quals augmenten eficientment les seves defenses antioxidants i no sofreixen peroxidació lipídica. A més, Caulerpa spp. augmenta les seves defenses antioxidants i caulerpenina en situacions de herviboria i epifitisme com a mecanisme defensiu.En la presente tesis doctoral se estudian los cambios en la comunidades bentónicas que se producen tras la sustitución de una pradera de Posidonia oceanica por algas invasoras del género Caulerpa (Caulerpa racemosa y Caulerpa taxifolia) y la caulerpal establecida Caulerpa prolifera. Las comunidades bentónicas cambian con la presencia de caulerpales. Las principales diferencias entre los cuatro hábitats estudiados son debidas a las diferentes abundancias de las especies coincidentes tanto para moluscos, decápodos como poliquetos. La comunidad de invertebrados presenta patrones estacionales diferentes entre esos cuatro hábitats y con Posidonia oceanica (referidos a abundancia y diversidad de especies). Las algas del género Caulerpa se caracterizan por poseer el metabolito secundario de defensa caulerpenina. La toxicidad de las caulerpales se traduce en un incremento de las defensas antioxidantes del los organismos que allí viven (Coris julis y Bittium reticulatum), los cuales aumentan eficientemente sus defensas antioxidantes sin sufrir peroxidación lipídica. Además, Caulerpa aumenta sus defensas antioxidantes y la caulerpenina en situaciones de herbivoría y epifitismo como mecanismo defensivo.In the present thesis, changes in the benthic communities caused by the substitution of Posidonia oceanica seagrass meadows by the invasive algae Caulerpa (Caulerpa racemosa and Caulerpa taxifolia) and the established Caulerpa prolifera are analyzed. Benthic communities change with the presence of Caulerpa spp. Main differences among studied habitats are due to differences in the abundances of invertebrate species common for the four habitats for Decapoda, Mollusca and Polychaeta. Seasonal patterns of invertebrate community are also different among the studied algae and seagrass (for abundances and species diversity indexes). Caulerpa macroalgae are characterised by the presence of caulerpenyne as defensive secondary metabolite. The toxicity of Caulerpa is expressed as an increased antioxidant response of the organisms living in Caulerpa mats (Coris julis and Bittium reticulatum), which efficiently increases its antioxidant defences avoiding lipid peroxidation. Caulerpa spp. also increases their antioxidant defences and caulerpenyne concentration in herbivorism and epifitism situations

Una nueva especie de Nuuanu (Amphipoda: Gammaridea: Melitidae) de fondos arenosos someros de las Islas Baleares (Mediterráneo occidental)

Publicación online disponible en: http://www.icm.csic.es/scimar/index.php[EN] Nuuanu beatricis n. sp., a new melitid amphipod, is described from shallow-water sandy bottoms on the S and SE coasts of Mallorca (Balearic Islands, Mediterranean). It differs from the rest of its congeners in the combination of: (1) non-geniculate antennule, much longer than antenna; (2) distal segment of mandibular palp shorter than second, armed with both D and E setae; (3) second segment of mandibular palp with 2 setae; (4) posteroventral lobe (sensu Lowry and Watson, 2002) absent from posterior margin of coxa 4; (5) reduced spine present on medial surface of coxa 5; (6) posterior margin of basis of pereopod 5 convex; (7) anterodistal lobe of coxa 7 wanting; (8) posterior margin of basis of pereopod 7 sparsely serrated along proximal half only; (9) pleonites 1-2 lacking dorsodistal spines; (10) anterodistal corner of epimeral plate 1 rounded; (11) exopod of uropod 3 longer than protopod; and (12) telson with terminal spine on each lobe. Although the new amphipod could be an alien species introduced from a distant tropical location with alien Caulerpa algae species, it is here regarded as an ancient Mediterranean element owing to its peracarid condition (i.e. reduced potential for dispersal), regressed visual apparatus, and crevicular-interstitial existence. The presumed presence of sternal gills in Nuuanu is rejected after demonstration of the coxal origin of the spiniform structures interpreted elsewhere as sternal gills.[ES] Nuuanu beatricis n. sp. difiere del resto de congéneres por la combinación de: (1) anténula no geniculada, mucho más larga que la antena; (2) segmento distal del palpo mandibular más corto que el segundo, armado con sedas tipo D y E; (3) segundo segmento del palpo mandibular con 2 sedas; (4) margen posterior de la coxa 4 sin lóbulo posteroventral (sensu Lowry y Watson, 2002); (5) superficie medial de la coxa 5 con una pequeña espina; (6) base del pereópodo 5 con el margen posterior convexo; (7) coxa 7 sin lóbulo anterodistal; (8) base del pereópodo 7 con el margen posterior serrado laxamente sólo a lo largo de la mitad proximal; (9) pleonitos 1-2 sin espinas dorsodistales; (10) placa epimeral 1 con el extremo anterodistal redondeado; (11) urópodo 3 con el exópodo más largo que el protópodo; y (12) telson con una espina terminal sobre cada lóbulo. Aunque podría tratarse de una especie tropical introducida recientemente en el Mediterráneo junto con especies también alóctonas de alga Caulerpa, es más probable que la nueva especie se corresponda con un elemento paleomediterráneo dada su condición peracárida (que conlleva un bajo potencial dispersivo), la regresión de su aparato visual, además de su ligazón al medio crevicular-intersticial. Se descarta la supuesta presencia de branquias esternales en Nuuanu tras demostrarse el origen coxal de de las estructuras espiniformes interpretadas hasta ahora como tales.This work was supported by the project CAULEXPAN (REN2002-00701, Spanish Ministry of Science and Education) and the Taxonomic Clearing Facility of the EU Network of Excellence MARBEF.Peer reviewe

Ecología de Caulerpales: Fauna y Biomarcadores

En la presente tesis doctoral se estudian los cambios en la comunidades bentónicas que se producen tras la sustitución de una pradera de Posidonia oceanica por algas invasoras del género Caulerpa (Caulerpa racemosa y Caulerpa taxifolia) y la caulerpal establecida Caulerpa prolifera. Las comunidades bentónicas cambian con la presencia de caulerpales. Las principales diferencias entre los cuatro hábitats estudiados son debidas a las diferentes abundancias de las especies coincidentes tanto para moluscos, decápodos como poliquetos. La comunidad de invertebrados presenta patrones estacionales diferentes entre esos cuatro hábitats y con Posidonia oceanica (referidos a abundancia y diversidad de especies).Las algas del género Caulerpa se caracterizan por poseer el metabolito secundario de defensa caulerpenina. La toxicidad de las caulerpales se traduce en un incremento de las defensas antioxidantes del los organismos que allí viven (Coris julis y Bittium reticulatum), los cuales aumentan eficientemente sus defensas antioxidantes sin sufrir peroxidación lipídica. Además, Caulerpa aumenta sus defensas antioxidantes y la caulerpenina en situaciones de herbivoría y epifitismo como mecanismo defensivo.En la present tesis doctoral són estudiats els canvis en les comunitats bentòniques produïts per la substitució de praderies de Posidonia oceanica per algues invasores del gènere Caulerpa (Caulerpa racemosa y Caulerpa taxifolia) i la caulerpal establida Caulerpa prolifera. Les comunitats bentòniques canvien amb la presència de les caulerpals. Les principals diferències entre els quatre hàbitats són degudes a les diferents abundàncies que presenten les espècies coincidents tant per mol·lusc, decàpodes com poliquets. A més, la comunitat d'invertebrats té patrons estacionals diferents entre els quatre hàbitats (referits a abundància i diversitat de espècies).Les algues del gènere Caulerpa es caracteritzen per contenir caulerpenina com metabòlit secundari de defensa. La toxicitat de les caulerpals es veu reflectida en un increment de les defenses antioxidants dels organismes que hi viuen en hàbitats de Caulerpa (Coris julis i Bittium reticulatum), els quals augmenten eficientment les seves defenses antioxidants i no sofreixen peroxidació lipídica. A més, Caulerpa spp. augmenta les seves defenses antioxidants i caulerpenina en situacions de herviboria i epifitisme com a mecanisme defensiu.In the present thesis, changes in the benthic communities caused by the substitution of Posidonia oceanica seagrass meadows by the invasive algae Caulerpa (Caulerpa racemosa and Caulerpa taxifolia) and the established Caulerpa prolifera are analyzed. Benthic communities change with the presence of Caulerpa spp. Main differences among studied habitats are due to differences in the abundances of invertebrate species common for the four habitats for Decapoda, Mollusca and Polychaeta. Seasonal patterns of invertebrate community are also different among the studied algae and seagrass (for abundances and species diversity indexes).Caulerpa macroalgae are characterised by the presence of caulerpenyne as defensive secondary metabolite. The toxicity of Caulerpa is expressed as an increased antioxidant response of the organisms living in Caulerpa mats (Coris julis and Bittium reticulatum), which efficiently increases its antioxidant defences avoiding lipid peroxidation. Caulerpa spp. also increases their antioxidant defences and caulerpenyne concentration in herbivorism and epifitism situations

Effects of invasive seaweeds on feeding preference and performance of a keystone Mediterranean herbivore

The consequences of invasive species on ecosystem processes and ecological interactions remain poorly understood. Predator-prey interactions are fundamental in shaping species evolution and community structure and can be strongly modified by species introductions. To fully understand the ecological effects of invasive species on trophic linkages it is important to characterize novel interactions between native predators and exotic prey and to identify the impacts of invasive species on the performance of native predators. Although seaweed invasions are a growing global concern, our understanding of invasive algae-herbivore interactions is still very limited. We used a series of feeding experiments between a native herbivore and four invasive algae in the Mediterranean Sea to examine the potential of native sea urchins to consume invasive seaweeds and the impacts of invasive seaweed on herbivore performance. We found that three of the four invasive species examined are avoided by native herbivores, and that feeding behaviour in sea urchins is not driven by plant nutritional quality. On the other hand, Caulerpa racemosa is readily consumed by sea urchins, but may escape enemy control by reducing their performance. Recognizing the negative impacts of C. racemosa on herbivore performance has highlighted an enemy escape mechanism that contributes to explaining how this widespread invasive alga, which is preferred and consumed by herbivores, is not eradicated by grazing in the field. Furthermore, given the ecological and economic importance of sea urchins, negative impacts of invasive seaweeds on their performance could have dramatic effects on ecosystem function and services, and should be accounted for in sea urchin population management strategies. © 2010 Springer Science+Business Media B.V.Financial support was provided by Grant CTM2005-01434/MAR from the Spanish Ministry of Science and Innovation. FT was funded by Juan de la Cierva Postdoctoral Fellowship.Peer Reviewe

Occurrence of Automate branchialis Holthuis & Gottlieb, 1958 (Decapoda, Alpheidae) in the Balearic Islands (western Mediterranean Sea)

7 pages, 3 figures, 1 tableThe faunistic composition of Mediterranean marine ecosystems is still far from being well known, despite the intensive effort to increase our knowledge on biodiversity all over the planet. Many marine ecosystems are as yet poorly understood, including even many sublittoral and shallow water areas. Decapod crustaceans constitute a relatively well studied faunistic group within the Mediterranean Sea (Zariquiey-Álvarez, 1968; d’Udekem d’Acoz, 1999). However, the Mediterranean is not a stable environment and it is a region with a strong faunistic influence both from the Atlantic Ocean in the west, through the Strait of Gibraltar, and also from the Indian Ocean and Red Sea in the east, since the opening of the Suez Canal in 1869. Within the framework of a research project aiming to evaluate the effects of the colonization of the rhizomes of the seagrass, Posidonia oceanica (L.) Delile by the macroalga Caulerpa, specimens of decapod crustaceans were collected. Individuals were sampled from the sediment among the rhizomes of P. oceanica during 2003-2005 in Mallorca (fig. 1). Infaunal communities were sampled with a square of 20 × 20 cm and a height of 5 cm, thus sampling a total volume of 2000 cm3, and sorted with 500 μmmesh. Four specimens of an alpheid shrimp, attributed to Automate branchialis Holthuis & Gottlieb, 1958 (Caridea, Alpheidae), were found at the rhizomes of Posidonia oceanica beds at Cala d’Or (Mallorca, Balearic Islands, western Mediterranean) (table I; fig. 1). No Automate branchialis were collected in the leaves stratum that was sampled with a hand-net of 20 × 40 cm along straight transects of 20 meters.This research was funded by the Ministerio de Ciencia y Tecnología (Plan Nacional I+D (REN2002-00701/MAR)). The first author was funded by postgraduate research grant I3P FSE.Peer reviewe

Occurrence of Automate branchialis Holthuis & Gottlieb, 1958 (Decapoda, Alpheidae) in the Balearic Islands (western Mediterranean Sea)

7 pages, 3 figures, 1 tableThe faunistic composition of Mediterranean marine ecosystems is still far from being well known, despite the intensive effort to increase our knowledge on biodiversity all over the planet. Many marine ecosystems are as yet poorly understood, including even many sublittoral and shallow water areas. Decapod crustaceans constitute a relatively well studied faunistic group within the Mediterranean Sea (Zariquiey-Álvarez, 1968; d’Udekem d’Acoz, 1999). However, the Mediterranean is not a stable environment and it is a region with a strong faunistic influence both from the Atlantic Ocean in the west, through the Strait of Gibraltar, and also from the Indian Ocean and Red Sea in the east, since the opening of the Suez Canal in 1869. Within the framework of a research project aiming to evaluate the effects of the colonization of the rhizomes of the seagrass, Posidonia oceanica (L.) Delile by the macroalga Caulerpa, specimens of decapod crustaceans were collected. Individuals were sampled from the sediment among the rhizomes of P. oceanica during 2003-2005 in Mallorca (fig. 1). Infaunal communities were sampled with a square of 20 × 20 cm and a height of 5 cm, thus sampling a total volume of 2000 cm3, and sorted with 500 μmmesh. Four specimens of an alpheid shrimp, attributed to Automate branchialis Holthuis & Gottlieb, 1958 (Caridea, Alpheidae), were found at the rhizomes of Posidonia oceanica beds at Cala d’Or (Mallorca, Balearic Islands, western Mediterranean) (table I; fig. 1). No Automate branchialis were collected in the leaves stratum that was sampled with a hand-net of 20 × 40 cm along straight transects of 20 metersThis research was funded by the Ministerio de Ciencia y Tecnología (Plan Nacional I+D (REN2002-00701/MAR)). The first author was funded by postgraduate research grant I3P FSEPeer reviewe

Combining stable isotopes and biochemical markers to assess organic contamination in transplanted Mussels Mytilus Galloprovincialis.

Capítulo en: McGEVIN, Lauren E. (ed.). Mussels: Anatomy, Habitat and Environmental Impact. [S.l.]: Nova Science Publishers, 2011. ISBN 978-1-61761-763-8Marine pollution and water quality are evaluated on direct measurements of the abiotic variables and also on bioaccumulation measurements of chemical contaminants in marine organisms. Measuring the same biomarkers in different localities simultaneously gives information about the pollution states and provides a better comprehension of the mechanistic model of action of environmental pollutants on the organisms. The use of biomarkers to evaluate stressful situations is widely extended in bivalves. In the current work, organic compound concentrations (dichlorodiphenyltrichloroethane isomers, dioxins, PCBs and PAHs), antioxidant biomarkers (malondialdehyde, catalase, glutathione peroxidase, superoxide dismutase and glutathione reductase) and isotopic composition (15N and 13C) were measured in the digestive gland and gill tissues of the mussel Mytilus galloprovincialis in coastal waters of the Balearic Islands (Western Mediterranean) in order to assess pollution levels in these waters. The highest concentrations of PAHs corresponded to naphthalene, acenaphthylene, fluorene and phenanthrene, with the harbours of Santa Eulàlia and Eïvissa having the highest levels of PAHs. Oxidative stress and biomarkers are used as indicators of pollution exposure, showing that pollution can not evidence exposure effects, while the antioxidant responses can change with time. In the current work, the existence of pollution was indicated by the positive correlation between the concentrations of the lighter PCBs in the digestive gland of the mussels and catalase and glutathione reductase enzyme activities. Gills showed a correlation between the lighter PCBs and superoxide dismutase activity, indicating the bioaccumulation of these organic compounds. Carbon and nitrogen isotopic signatures showed a clear trend for differences in tissue distribution among the studied localities, with the digestive gland being more enriched in carbon and nitrogen than the gills. PCA for biomarkers also showed that tissues responded differently at sampling stations. The presence of pollutants could be the responsible for the changes described in the isotopic composition and in the antioxidant defences of the mussel M. galloprovincialis in waters of the Balearic Islands. The correlations between organic pollutants and the isotopic composition and biomarkers in M. galloprovincialis suggest that these measures could represent a good proxy for evaluation of contamination, additional to the chemical characterisation.Peer Reviewe

Antioxidant response and caulerpenyne production of the alien Caulerpa taxifolia (Vahl) epiphytized by the invasive algae Lophocladia lallemandii (Montagne)

5 pages, 4 figures, 1 table.-- Printed version published on Sep 12, 2008.Invasive algae alter the structure and function of ecosystems. The red algae Lophocladia lallemandii grows in the West Mediterranean epiphyting the green algae Caulerpa taxifolia, another invasive alga. Our aim was to determine whether the invasive algae Lophocladia, recently introduced in the West Mediterranean, induces oxidative stress and an antioxidant response in Caulerpa taxifolia. We measured the caulerpenyne production, the activities of antioxidant enzymes and the levels of markers of lipid peroxidation in Caulerpa taxifolia. Caulerpenyne concentration was significantly higher in Caulerpa taxifolia epiphytized by Lophocladia. End-products of lipid peroxidation -malondialdehyde (MDA) and 4-hydroxinonenal (4-HNE)- were significantly increased in Caulerpa taxifolia samples from the station with Lophocladia. Antioxidant enzyme activities -catalase and superoxide dismutase (SOD)-, as well as H2O2 production significantly increased in the Lophocladia station compared to the control station. The activities of catalase and SOD determined in Lophocladia lallemandii showed no significant differences between Lophocladia living alone and Lophocladia epiphytating Caulerpa taxifolia. Caulerpa taxifolia epiphytized by Lophocladia lallemandii responded by increasing the caulerpenyne and H2O2 production and the antioxidant enzymes activities as a defensive mechanism against the new invasive algae.This work was supported by the projects “Expansión de Caulerpa prolifera, C. taxifolia y C. racemosa en el Mediterráneo: dinámica clonal, producción y destino de la producción” REN2002-00701/MAR and “Macroalgas marinas invasoras en las islas Baleares: Evaluación de riesgos y efectos en comunidades bentónicas” CTM2005-01434/MAR.Peer reviewe

Antioxidant response of the seagrass Posidonia oceanica when epiphytized by the invasive macroalgae Lophocladia lallemandii

5 pages, 2 figures.-- Printed version published Sep 2008.The aim was to evaluate the antioxidant defences and the occurrence of oxidative damage in Posidonia oceanica under a stress situation due to the epiphytism of the invasive macroalgae Lophocladia lallemandii. P. oceanica leaves were collected in the absence (control station) and in the presence of the epiphytic algae L. lallemandii and the antioxidant enzyme activities, markers of oxidative damage, and hydrogen peroxide production were determined. Antioxidant enzyme - catalase, glutathione peroxidase and superoxide dismutase – activities were significantly higher in Posidonia epiphytized by L. lallemandii. Malondialdehyde, protein carbonyl derivates, and glutathione levels were also higher in L. lallemandii epiphytized P. oceanica leaves compared to control samples. The production of hydrogen peroxide was also significantly increased when Posidonia was epiphytized by L. lallemandii. The invasion of P. oceanica meadows by L. lallemandii appeared to induce oxidative stress in the seagrass as evidenced by increased levels of oxidative stress markers and antioxidant defences.This work was supported by the project “Macroalgas marinas invasoras en las islas Baleares: Evaluación de riesgos y efectos en comunidades bentónicas” CTM2005-01434/MAR, and by Direcció General de Recerca, Desenvolupament Tecnològic i Innovació de la Conselleria d’Economia, Hisenda i Innovació “Acció Especial, 2007 Aplicacions dels biomarcadors en el musclo Mytilus galloprovincialis ”.Peer reviewe

Performance of circle hooks in a Mixed-species recreational fishery

The effects of the circle-hook on hooking injury, fish size and catch rates were evaluated for mixed-species recreational boat fisheries in the Balearic Islands (NW Mediterranean). The relationships between deep-hooking incidence (the main cause of fish mortality) and hook type (circle hooks vs conventional J-hooks), fish size, and angler were tested. Results demonstrated that the size of the fish was the most important predictor of deep-hooking incidence, as a larger fish size resulted in an increase in deeper wounds. Hook type also had a significant effect on the deep-hooking rate. Specifically, the deep-hooking rate of the most frequently-caught species, Diplodus annularis (L.) and Coris julis (L.), was reduced by greater than half with the circle hooks. The mean size of the fish caught and the unhooking time were not affected by the use of circle hooks. Finally, their use resulted in no change in the catch per unit effort (CPUE) compared to conventional hooks for both univariate and multivariate procedures. Hence, circle hooks are a promising conservation tool for marine resources when linked with catch-and-release strategies. © 2009 Blackwell Verlag, Berlin.Peer Reviewe