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Bryozoans are the major component of marine macro-fouling communities. In the study, the relations between bryozoan species and environmental variables were investigated at seven stations along the Aegean coast in August and December 2015. Constant bryozoan species in both sampling periods were Bugula neritina, Amathia verticillata, Shizoporella errata, Cryptosula pallasiana and Celleporaria brunnea. Their relationship with physico-chemical variables (Temperature, salinity, pH, dissolved oxygen, ammonium, nitrite and nitrate nitrogen, orthophosphate phosphorous, total phosphate, chlorophyll-a) were analysed by means of logistic regression analysis. The result showed that temperature with B. neritina; NH 4 -N, oPO 4 -P and TPO 4 -P with A verticillata; dissolved oxygen concentrations with S. errata and C. brunnea were positively related (p < 0.05)., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The increasing number of anthropogenic areas in the marine environment results in significant impact to adjacent ecosystems. In fact, the presence of marinas modifies the original environmental conditions and ends up disturbing the faunal community. However, despite the essential role displayed by the macrofauna on marinas' fouling biota, certain taxa such as polychaetes have been poorly studied. The present study provides the first spatial characterization of the epibiont polychaete fauna associated with the bryozoan Bugula neritina in marinas along the Iberian Peninsula and the north of Morocco. A total of 32 polychaete species were identified, with Syllidae being the most diverse family. Furthermore, the environmental factors involved in the occurrence and abundance of the dominant species Salvatoria clavata were also analyzed by Generalized Linear Models; results showed that the highest predicted values of S. clavata abundance appeared at marinas with high levels of nutrient enrichment and of heavy metals concentration., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Few studies to date have investigated the effects of ocean acidification on non-reef forming marine invertebrates with non-feeding larvae. Here, we exposed adults of the bryozoan Bugula neritina and their larvae to lowered pH. We monitored spawning, larval swimming, settlement, and post-settlement individual sizes at two pHs (7.9 vs. 7.6) and settlement dynamics alone over a broader pH range (8.0 down to 6.5). Our results show that spawning was not affected by adult exposure (48h at pH7.6), larvae swam 32% faster and the newly-settled individuals grew significantly larger (5%) at pH7.6 than in the control. Although larvae required more time to settle when pH was lowered, reduced pH was not lethal, even down to pH6.5. Overall, this fouling species appeared to be robust to acidification, and yet, indirect effects such as prolonging the pelagic larval duration could increase predation risk, and might negatively impact population dynamics., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Bryozoans are among the most abundant and diverse members of the Antarctic benthos, however the role of bioactive metabolites in ecological interactions has been scarcely studied. To extend our knowledge about the chemical ecology of Antarctic bryozoans, crude ether extracts (EE) and butanol extracts (BE) obtained from two Antarctic common species (Cornucopina pectogemma and Nematoflustra flagellata), were tested for antibacterial and repellent activities. The extracts were screened for quorum quenching and antibacterial activities against four Antarctic bacterial strains (Bacillus aquimaris, Micrococcus sp., Oceanobacillus sp. and Paracoccus sp.). The Antarctic amphipod Cheirimedon femoratus and the sea star Odontaster validus were selected as sympatric predators to perform anti-predatory and substrate preference assays. No quorum quenching activity was detected in any of the extracts, while all EE exhibited growth inhibition towards at least one bacterium strain. Although the species were not repellent against the sea star, they caused repellence to the amphipods in both extracts, suggesting that defence activities against predation derive from both lipophilic and hydrophilic metabolites. In the substrate preference assays, one EE and one BE deriving from different specimens of the species C. pectogemma were active. This study reveals intraspecific variability of chemical defences and supports the fact that chemically mediated interactions are common in Antarctic bryozoans as means of protection against fouling and predation., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

There are a number of remote archipelagos distributed between 45 and 60 °S. The biota of these islands provide useful information to describe and understand patterns in biodiversity and biogeography as well as potential impacts of climate change on marine ecosystems. They are in key locations either side of the Polar Front but also have limited influence from human activities. Here we investigate one taxon, bryozoans, on South Atlantic shelf habitats of the Falkland (FI) and the sub-Antarctic island of South Georgia (SG). We present new data on spatial distribution in these islands, as well as an analysis of the bryozoological similarities between these and neighbouring regions. A total of 85 species of cheilostome bryozoans (351 samples) were found, belonging to 33 genera, including 18 potentially new genera and 23 new species. Remarkably 65% and 41% of species were reported for the first time at FI and SG, respectively. The highest and the lowest value of species richness and species/genus ratio were found at East (EFI) and West Falkland (WFI), respectively, likely showing a tendency for stronger intrageneric competition. New data from this study were jointly analysed with data from the literature and existing databases, revealing new bathymetric ranges in 32 species. The biogeographic affinities of the bryozoans found give further evidence of the hypothesis of sequential separation of Gondwana and support the changing concept that although the Polar Front acts as a circumpolar biogeographic barrier it is not as impermeable as originally thought. Potential dispersal mechanisms are also discussed., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Many aquatic animals grow into colonies of repeated, genetically identical, modules (zooids). Zooid interconnections enable colonies to behave as integrated functional units, while plastic responses to environmental changes may affect individual zooids. Plasticity includes the variable partitioning of resources to sexual reproduction, colony growth and maintenance. Maintenance often involves regeneration, which is also a routine part of the life history in some organisms, such as bryozoans. Here we investigate changes in regenerative capacity in the encrusting bryozoan Cryptosula pallasiana when cultured at different seawater pCO 2 levels. The proportion of active zooids showing polypide regeneration was highest at current oceanic pH (8.1), but decreased progressively as pH declined below that value, reaching a six-fold reduction at pH 7.0. The zone of budding of new zooids at the colony periphery declined in size below pH 7.7. Under elevated pCO 2 conditions, already experienced sporadically in coastal areas, skeletal corrosion was accompanied by the proportional reallocation of resources from polypide regeneration in old zooids to the budding of new zooids at the edge of the colony. Thus, future ocean acidification can affect colonial organisms by changing how they allocate resources, with potentially profound impacts on life-history patterns and ecological interactions., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Freshwater invertebrates often disperse between discrete habitat patches via the production of dormant propagules. Being dispersed passively by animal vectors or wind, certain adaptations for exposures to terrestrial and aerial conditions like desiccation and freezing are required. In the present study, we investigate the mechanisms of survival and physiological adaptations due to desiccation and low temperatures in the statoblasts of two populations of the freshwater bryozoan Cristatella mucedo. Our results show that both sessoblasts and floatoblasts tolerate almost complete desiccation and subzero temperatures. Trehalose, a non-reducing disaccharide which has been related to desiccation tolerance, was detected by amperometric chromatography. However, due to the low concentrations found, it is unlikely that trehalose is playing a major part in desiccation tolerance of bryozoan statoblasts. Vitrification is assumed to be important in the survival of desiccation tolerant organisms. Differential scanning calorimetry revealed thermal transitions (T(g) onset around 70°C) in desiccated statoblasts, indicating that a vitreous matrix is present. During the exposure to subzero temperatures, freeze tolerance of statoblasts was confirmed by the detection of internal ice formation, which took place at a crystallisation temperature of between -6°C and -12°C., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The toxic effects of three inorganic metals (Cu, Cr, Hg), three organic (phenol, formalin, ammonium) chemicals, ozone-enriched water and peroxides (H2O2) on embryonic development were tested in 8 species from the Porifera, Bryozoa and Crustacea. Toxicants with lower molecular weight showed stronger negative impacts on post-diapause embryos than chemicals with higher molecular weight if related to the toxicity of the chemicals to active adult stages. Only few embryos of the cladoceran Moina macrocopa and none of the cladoceran Wlassicsia pannonica treated with peroxides at concentration 0.3% developed further. Ozone-enriched water had no significant effect on post-diapause embryonic development in cladocerans. Ammonium (the product of NH4OH dissociation) in concentration 100 mg/l and higher killed all embryos of M. macrocopa inside protective membranes. Peroxides and ammonium are suggested for the purification of ship ballast waters as effective, non-expensive and non-persistent toxic chemicals. Resting stages of invertebrates including at least Crustaceans, Porifera and Bryozoa seem to allow not only dispersal among toxic industrial environments such as ship ballast compartments, but may also endure serious pollution events common in seaports and estuaries. Artemia cysts due to their strong protection against different toxic substances are recommended as a model for studies of toxic effects in diapausing stages in polluted estuaries and marine environments., (Copyright 2010 Elsevier Ltd. All rights reserved.)

The new occurrence of the bryozoan Zoobotryon verticillatum Della Chiaje, 1822 is herein recorded in multiple places throughout Azores archipelago. Where introduced, this species has caused important ecological and economical damage and therefore is regarded as invasive. In the Azores, no detrimental effects have yet been noted. The species is so far restricted to marinas (Horta, Faial Island; Vila Franca do Campo, São Miguel Island) and a natural coastal pool located near a secondary harbour (Lajes do Pico, Pico Island). A total of 29 colonies were counted during a specific survey conducted in August 2008 in the marina of Horta. The distribution of the species throughout the eastern and central island groups denotes a wide dispersion area and offers control or eradication measures a low probability of success together with the lack of harbour management practices that could effectively prevent the arrival, settlement and dispersal of non-native species transported by human-assisted means.