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Sponge Species (sponge + species)
Selected AbstractsDynamics Behind Standoff Interactions in Three Reef Sponge Species and the Coral Montastraea cavernosaMARINE ECOLOGY, Issue 3-4 2000Lisanne A. M. Aerts Abstract. Benthic organisms compete for space, and standoff interactions, i. e. interactions with no clearly observable outcome such as win or loss, are very common in marine hard substratum communities. Standoffs were more common than overgrowths among all sponge-coral interactions observed in a coral reef community off Santa Marta, NE Colombia. The dynamics of these standoffs and the role played by each of the interacting organisms were examined in a series of standard observations of sponge-coral interactions involving the sponge species Niphates erecta, Rhaphidophlus venosus, Scopalina ruetzleri and the coral Montastraea cavernosa. Most sponge-coral standoffs in this study displayed rapid changes in number of polyps along the coral border, sponge area and sponge-coral distance. The outcome of sponge-coral standoffs depended on the ecological stategy (e.g., growth) of the sponge species. Scopalina ruetzleri and N. erecta did not show any signs of direct competition with Montastraea cavernosa. R. venosus, however, was often observed to take over vacant space formed by dead coral polyps (54 % of interactions). The impact of coral damage (lesions) on the interaction process between R. venosus and M. cavernosa was shown by a significant increase in coral polyp death in damaged compared with undamaged M. cavernosa colonies (22.7 % versus 6.9 %). This study demonstrates that (1) sponge-coral standoffs are actually quite dynamic because of the continually changing distance between the organisms, (2) the dynamic nature of sponge-coral standoffs depends on growth-related strategies (growth form, growth rate) of the competing sponge species, (3) the actual frequency of coral overgrowth by (thinly encrusting) sponge species can only be determined by means of intermittent observations; space gained at the cost of coral tissue cannot be seen by single observations, (4) coral damage (lesions) on reefs may enhance deterioration of corals by increasing their susceptibility to sponge overgrowth. [source] The distribution and prevalence of sponges in relation to environmental gradients within a temperate sea lough: inclined cliff surfacesDIVERSITY AND DISTRIBUTIONS, Issue 6 2000James J. Bell Abstract. Sponge communities on inclined cliff surfaces (40°) at Lough Hyne Marine Nature Reserve, Co. Cork, Ireland were sampled at five sites (four inside the lough and one on the adjacent Atlantic coast). Each site varied in sedimentation rate and flow regime. Sites ranged from turbulent (with negligible sedimentation) to very low flow (< 3 cm,1) and highly sedimented regimes. Sponge species showed variation between sites and depth. The greatest difference in sponge communities was observed between the most turbulent and most sedimented sites. The distinct zonation patterns, present at all sites, were most pronounced at the highly sedimented sites. Encrusting forms constituted a high proportion of the sponges at all sites. However encrusting species found at the turbulent site were different to those at the sedimented sites. Arborescent species were common, mainly at the sedimented sites within Lough Hyne. Distributions of sponge species are considered with respect to morphological adaptation, competition and physiological adaptation. The distributions of sponge species on inclined surfaces are also compared with those on vertical cliff faces. [source] The distribution and prevalence of sponges in relation to environmental gradients within a temperate sea lough: vertical cliff surfacesDIVERSITY AND DISTRIBUTIONS, Issue 6 2000James J. Bell Abstract. The prevalence and distribution of sponges was surveyed on vertical cliff surfaces at Lough Hyne Marine Nature Reserve, Co. Cork, Ireland. The number of sponge species was recorded at 6-metre depth intervals at four sites within Lough Hyne, and at one site on the adjacent Atlantic coastline to examine differences in abundance and zonation patterns. Sites ranged from an exposed turbulent regime to sheltered, sedimented environments. Individual species showed different distributions and prevalence between sites and with increasing depth. Greatest differences were observed between the most- and least-disturbed sites. Distinct sponge zonation patterns were evident at all sites sampled. Twenty-five species were considered dominant at all five sites with the remaining 48 species considered rare. Only four of the 25 most-dominant species occurred at the site experiencing the most turbulent flow conditions, whereas 12 species were found at the site of unidirectional fast flow. At sites of moderate to slight water movement and high sedimentation, between 18 and 24 of the most dominant species were present. Encrusting forms constituted high proportions of sponge communities at all five sites sampled (although consisting of different species). At sites of turbulent and unidirectional fast flow massive forms also dominated whereas at the least turbulent sites, where sedimentation was high, arborescent sponges were abundant. Few species showed exclusive distribution to a single depth and site, but there was some degree of correlation between species distributions and abiotic factors such as sedimentation rate and flow regimes. Sponge distributions and densities are discussed with respect to the suitability of species' morphologies to particular environments, intra-specific and inter-specific competition and physiological adaptations that enable them to survive in different habitats. [source] The distribution and prevalence of sponges in relation to environmental gradients within a temperate sea lough: inclined cliff surfacesDIVERSITY AND DISTRIBUTIONS, Issue 6 2000James J. Bell Abstract. Sponge communities on inclined cliff surfaces (40°) at Lough Hyne Marine Nature Reserve, Co. Cork, Ireland were sampled at five sites (four inside the lough and one on the adjacent Atlantic coast). Each site varied in sedimentation rate and flow regime. Sites ranged from turbulent (with negligible sedimentation) to very low flow (< 3 cm,1) and highly sedimented regimes. Sponge species showed variation between sites and depth. The greatest difference in sponge communities was observed between the most turbulent and most sedimented sites. The distinct zonation patterns, present at all sites, were most pronounced at the highly sedimented sites. Encrusting forms constituted a high proportion of the sponges at all sites. However encrusting species found at the turbulent site were different to those at the sedimented sites. Arborescent species were common, mainly at the sedimented sites within Lough Hyne. Distributions of sponge species are considered with respect to morphological adaptation, competition and physiological adaptation. The distributions of sponge species on inclined surfaces are also compared with those on vertical cliff faces. [source] Sponges as biomonitors of heavy metals in spatial and temporal surveys in northwestern Mediterranean: Multispecies comparison,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2007Emma Cebrian Abstract Contamination by heavy metals has increased drastically in the coastal Mediterranean during the last 20 years. A comparative study on metal bioaccumulation by four widespread sponge species (Crambe crambe, Chondrosia reniformis, Phorbas tenacior, and Dysidea avara) has been performed to select the most suitable species for metal monitoring. Copper bioaccumulation fits an accumulation strategy while Pb concentration seems to be regulated in most sponges. Crambe crambe was the only studied species that bioaccumulated Pb and Cu as a function of the available metal, proving its suitability for monitoring purposes. Then, we examined its effectiveness as a bioindicator at large spatial and temporal scales, comparing metal accumulation in this species and in sediments. Crambe crambe provided accurate information on the background levels of metals in the area at both spatial and temporal scales, and furthermore it reflected seasonal fluctuations of the bioavailable metals, which would be impossible to assess by means of a sediment survey. [source] Differences in reproductive timing among sponges sharing habitat and thermal regimeINVERTEBRATE BIOLOGY, Issue 4 2008Ana Riesgo Abstract. The reproductive cycles of four Mediterranean demosponges (Axinella damicornis, Corticium candelabrum, Raspaciona aculeata, and Chondrosia reniformis) were investigated during 2 consecutive years. Three of the species had annual gametogenic cycles characterized by a single peak of gamete production, but members of C. candelabrum showed continuous oocyte production during the 2 years. The relationship between gametogenic dynamics and seawater temperature varied substantially among species, contrary to the widespread belief that gamete production is associated with seasonal water warming. The annual temperature increase (in June) concurred with oocyte production only in C. reniformis, although maximum temperatures were simultaneous with the production of both oocytes in R. aculeata and sperm in C. reniformis. In contrast, the annual temperature decline in October was associated with both oogenesis in A. damicornis and spermatogenesis in R. aculeata. Spermatogenesis in A. damicornis started after a 5-month period of low-temperature values (December,April in 2004 and November,March in 2005). Likewise, in C. candelabrum, spermatogenesis started after a 3-month period of low-temperature values (November,February), a period concomitant with a slow increase in oocyte production. These findings reveal that sponge species that cooccur and share similar thermal regimes may differ substantially in their timing of gamete production. If we are to predict the future effects of climate change on marine benthic communities, there is an urgent need to improve our knowledge of the species-specific relationship between timing of gametogenesis and temperature, at least for those sponges that are key species in benthic communities. [source] Dynamics Behind Standoff Interactions in Three Reef Sponge Species and the Coral Montastraea cavernosaMARINE ECOLOGY, Issue 3-4 2000Lisanne A. M. Aerts Abstract. Benthic organisms compete for space, and standoff interactions, i. e. interactions with no clearly observable outcome such as win or loss, are very common in marine hard substratum communities. Standoffs were more common than overgrowths among all sponge-coral interactions observed in a coral reef community off Santa Marta, NE Colombia. The dynamics of these standoffs and the role played by each of the interacting organisms were examined in a series of standard observations of sponge-coral interactions involving the sponge species Niphates erecta, Rhaphidophlus venosus, Scopalina ruetzleri and the coral Montastraea cavernosa. Most sponge-coral standoffs in this study displayed rapid changes in number of polyps along the coral border, sponge area and sponge-coral distance. The outcome of sponge-coral standoffs depended on the ecological stategy (e.g., growth) of the sponge species. Scopalina ruetzleri and N. erecta did not show any signs of direct competition with Montastraea cavernosa. R. venosus, however, was often observed to take over vacant space formed by dead coral polyps (54 % of interactions). The impact of coral damage (lesions) on the interaction process between R. venosus and M. cavernosa was shown by a significant increase in coral polyp death in damaged compared with undamaged M. cavernosa colonies (22.7 % versus 6.9 %). This study demonstrates that (1) sponge-coral standoffs are actually quite dynamic because of the continually changing distance between the organisms, (2) the dynamic nature of sponge-coral standoffs depends on growth-related strategies (growth form, growth rate) of the competing sponge species, (3) the actual frequency of coral overgrowth by (thinly encrusting) sponge species can only be determined by means of intermittent observations; space gained at the cost of coral tissue cannot be seen by single observations, (4) coral damage (lesions) on reefs may enhance deterioration of corals by increasing their susceptibility to sponge overgrowth. [source] Quantifying sponge erosions in Western Australian pearl oyster shellsAQUACULTURE RESEARCH, Issue 9 2010Sabine Daume Abstract This paper describes several methods to estimate the amount of sponge erosion in pearl oyster shells (Pinctada maxima Jameson, 1901). Internal erosion can be calculated from non-destructive surface area estimates because a clear relationship was found between the eroded area on the surface of the shells and internal erosions. Grading shells into three different categories, according to the severity of erosion, also proved to be a suitable method to quickly assess the amount of sponge erosions. All methods were more accurate in shells with larger amounts of erosions. Using the described methods, the Lacepedes fishing ground was more diverse in bioeroding sponge species compared with sites at the 80-Mile fishing ground locations. Pione velans Hentschel, 1909 was the dominant bioeroding sponge species but Cliona dissimilis Ridley and Dendy, 1886 eroded more shell material than P. velans. Observed patterns suggest that P. velans had a more recent recruitment than C. dissimilis. We suggest that visual grading together with estimates from the shell surface will be sufficient to determine the general long-term trends in bioeroding sponge severity. However, results of monitoring programmes need to be supplemented by histological examination to confirm sponge activity and species identity. [source] The use of volunteers for conducting sponge biodiversity assessments and monitoring using a morphological approach on Indo-Pacific coral reefsAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2007James J. Bell Abstract 1.Sponges are an important component of coral reef ecosystems, but even though they are widespread with the ability to significantly influence other benthic community members they rarely feature to any great extent in current monitoring or biodiversity assessment programmes conducted by volunteer and professional groups. This exclusion is usually because of the taxonomic problems associated with sponge identification. 2.A potential alternative to monitoring temporal or spatial change in sponge assemblages and assessing biodiversity levels is to characterize sponges using morphologies present rather than collecting species data. Quantifying sponge biodiversity (for monitoring and biodiversity assessments) at the morphological level is less time and resource consuming than collecting species data and more suited to groups with little training and experience of sponge taxonomy or in regions where detailed taxonomic information on sponges is sparse. 3.This paper considers whether the same differences and similarities in sponge richness and assemblage composition can be identified using species and morphological data in response to environmental gradients at two coral reef ecosystems in south-east Sulawesi, Indonesia, and whether volunteers can be used to reliably collect morphological information. Sponge morphologies were classified into 14 groups and different morphological assemblages were found by the author at the two sites and between depth intervals. Comparisons of sponge species and morphological composition data showed that common patterns in assemblage structuring and richness could be identified irrespective of whether morphological or species data were used. In addition, a positive linear relationship was found between sponge species and morphological richness. 4.The morphological data recorded by volunteer divers (n=10) were compared with that collected by the author. Although volunteers recorded fewer sponges than the author (approximately 15% less), missing mainly small encrusting specimens, similar assemblage structure could be identified from both the volunteers' and the author's data. 5.The results showed that the same differences in sponge assemblages between sites and depths could be identified from both species and morphological data. In addition, these morphological data could be reliably collected by volunteer divers. Copyright © 2006 John Wiley & Sons, Ltd. [source] Experimental sponge fishery in Egypt during recovery from sponge diseaseAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2005J. Castritsi-Catharios Abstract 1.A survey was undertaken (1995) on the Mediterranean coast of Egypt that investigated four sponge fishing grounds. These fishing banks suffered from sponge disease between 1987 and 1990, causing a mass mortality of commercial sponges in the eastern and central Mediterranean. 2.Adult commercial sponges (length >10 cm) were harvested by divers in the infralittoral zone (depth range 17,36 m). The substratum at most of the sampling stations was hard, consisting mainly of plaques, rocks and heavy stones, sometimes covered by Posidonia oceanica. 3.Two commercial sponge species were detected, Hippospongia communis and Spongia cfr zimocca; the former was more prevalent and abundant. Light penetration in the area surveyed was high. The two commercial sponge species detected seemed to be well adapted to these conditions, as indicated by the colour of their external membranes, which were almost black due to enhanced pigment formation. The absence of Spongia officinalis, in the area surveyed may also be related to light penetration, since S. officinalis is a more sciaphilous species. 4.The shape of H. communis was almost spherical, and the average dimensions (length, width, height, circumference) increased with increasing depth of the fishing grounds. At shallower depths (<30 m), adult H. communis occurred in lower densities, whereas young commercial sponges were abundant. No signs of sponge disease were found. 5.It is concluded that the recovery of the four sponge fishing grounds was in progress, and that the repopulation of commercial sponges in the infralittoral zone showed a gradient from deeper to shallower waters. It is recommended to prohibit destructive fishing methods in the deeper waters in order to protect the population and its ability to regenerate. Copyright © 2005 John Wiley & Sons, Ltd. [source] | ||||||||||