Bryozoans exhibit a highly variable chemistry within their calcium carbonate skeletons. Previous studies have shown that the level of Mg-calcite in skeletons increases with increasing seawater temperature. For high-latitude regions such as the Antarctic, which have a low range of annual sea-temperature variation, there have been no studies on bryozoan skeletons with replicated sampling approaches suitable for statistical testing. Our aim was to conduct high-replicate, multi-site sampling to determine the variability in skeletal mineralogy of bryozoans from a site in Antarctica. During an expedition in January 2012, a total of 584 specimens representing 4 bryozoan species were collected from 8 sites at Adelaide Island, West Antarctic Peninsula, by SCUBA diving. All specimens were sampled within a 3 wk period and were selected to be of similar size, age and breeding status. We compared the variability in the wt% MgCO 3 in calcite of skeletons among species and investigated the relative influence of environmental and biological factors on skeleton chemistry. The results of X-ray diffraction analysis showed that the wt% MgCO 3 in calcite in bryozoan skeletons was statistically different among sites for all study species. The difference in wt% MgCO 3 among sites may be explained by habitat fragmentation driving directional adaptation of isolated populations to local environmental conditions. The relationship between Mg-calcite and temperature was inconsistent among species, and the predicted positive correlation between seawater temperature and Mg-calcite was not exhibited in any of the species examined. On this basis, we suggest that Antarctic bryozoan Mg-calcite should not be considered a reliable indicator of paleo-temperature.

Schizoporella japonica Ortmann was described from Japan but was subsequently introduced on Pacific oysters to the Pacific coast of North America, where it is now well established. In this paper we record it for the first time in European waters. The initial discovery was in a marina at Holyhead, North Wales, in July 2010 but S. japonica has since been observed abundantly in the Orkney Islands (from May 2011) and, subsequently, at other localities in northern Scotland. Introduction seems most likely to have been on an ocean-going vessel. The British material is here fully described and illustrated with SEMs and colour photographs; some unusual characters are discussed. Unlike other recently introduced bryozoans, S. japonica is a cold-water species and its breeding season in Britain extends through the winter. Extensive confusion between this and other species of Schizoporella on the west coast of Canada and the USA led us to make thorough morphometric comparisons between the species concerned (Schizoporella unicornis (Johnston in Wood), Schizoporella errata (Waters) and Schizoporella pseudoerrata Soule, Soule and Chaney). Zooid size in cheilostomate bryozoans is variable and often an unreliable character for species separation but shape (and therefore ratios between variables, which are independent of size) are often valuable: S. japonica zooids have a much greater length:width ratio than the other species. Density of frontal pseudopores provides a useful discriminatory character. Schizoporella unicornis, repeatedly reported in error from the Pacific coast of North America, does not occur there; it is a European species. Full comparisons are made between S. japonica and S. unicornis for European identification and between S. japonica, S. errata and S. pseudoerrata (which are also illustrated) for North American localities.

Abstract:Extensive marine growth on man-made structures in the ocean is commonplace, yet there has been limited discussion about the potential implications of marine growth for the wave and tidal energy industry. In response, the Environmental Interactions of Marine Renewables (EIMR) Biofouling Expert Workshop was convened. Discussions involved participants from the marine renewable energy (MRE) industry, anti-fouling industry, academic institutions and regulatory bodies. The workshop aimed to consider both the benefits and negative effects of biofouling from engineering and ecological perspectives. In order to form an agenda for future research in the area of biofouling and the marine renewable energy industry, 119 topics were generated, categorised and prioritised. Identified areas for future focus fell within four overarching categories: operation and maintenance; structured design and engineering; ecology; and knowledge exchange. It is clear that understanding and minimising biofouling impacts on MRE infrastructure will be vital to the successful development of a reliable and cost effective MRE industry.

Bryozoans exhibit a highly variable geochemistry within their calcium carbonate skeletons. Previous studies have predominantly attributed this variability to differences in seawater temperature influencing the relative deposition of aragonite and calcite, and the extent of magnesium incorporation into the calcite lattice. However, the patterns and scale of this variability have not been examined in detail. We conducted a high-replicate, multi-site study on the skeletal mineralogy of temperate Northern Hemisphere bryozoans to investigate the range of skeletal aragonite and Mg-calcite variability between species and the relative influence of environmental and biological factors on skeletal biogeochemistry. During a cruise in May 2012 in Scapa Flow, Orkney, Northeast Scotland, 480 specimens from 3 bryozoan species were collected by SCUBA diving. Samples were obtained from 5 study sites with similar depths and physical characteristics. All specimens were collected within the same week and were selected to be of similar size, age and breeding status. The results of X-ray diffraction analysis showed that wt% MgCO 3 in calcite and wt% aragonite in total CaCO 3 were statistically different between sites for all species. This may be explained by differential population connectivity between sites influenced by the tidal regimes of Scapa Flow. No temperate bryozoan species showed the expected positive trends of increasing wt% MgCO 3 in calcite or wt% aragonite in total CaCO 3 with seawater temperature. Based on the data generated in this study, we suggest that both environmental and biological factors are involved in the control of skeletal mineralogy in some temperate bryozoan species.