Make a difference: Choose artificial reefs over natural reefs to compensate for the environmental impacts of dive tourism

In the marine environment, natural reef habitats are amongst the most threatened by human activities. Although reef-based ecotourism can benefit local economies, dive tourism can damage sensitive habitats. One solution to managing conflicts between the economic value of diving and its ecological threats is the deployment of artificial reefs near popular dive sites. We surveyed recreational divers to assess divers' use, preference, and perceptions of diving artificial versus natural sites. We found that more divers prefer to dive in natural than artificial habitats, with associated biodiversity the most popular reason for preferring natural habitats, and appreciating shipwrecks the most popular reason for preferring artificial ones. Despite our sample population being highly educated and experienced, predominantly European divers, only 49 % of them perceived artificial reefs as important or somewhat important for diverting pressure from sensitive natural habitats. Similarly, only 13 % of respondents exhibited preference to avoid coral reefs to protect them. These results highlight the fact that more needs to be done to educate divers about the potential importance of artificial habitats in diverting divers from natural reefs. We suggest encouraging divers to switch out a proportion of their dives in vulnerable natural sites for artificial reefs. This is not only true for coral reefs, but should be applied to other natural reef habitats that are popular with divers such as kelp forests, sponge gardens and serpulid and coralligenous reefs. We hope that this study will provide a platform to stimulate a diver-led discussion and campaign for increased uptake of artificial reef use, resulting in reduced impacts on natural reefs

Transcriptome Sequencing and De Novo Analysis for Yesso Scallop (Patinopecten yessoensis) Using 454 GS FLX

BACKGROUND: Bivalves comprise 30,000 extant species, constituting the second largest group of mollusks. However, limited genetic research has focused on this group of animals so far, which is, in part, due to the lack of genomic resources. The advent of high-throughput sequencing technologies enables generation of genomic resources in a short time and at a minimal cost, and therefore provides a turning point for bivalve research. In the present study, we performed de novo transcriptome sequencing to first produce a comprehensive expressed sequence tag (EST) dataset for the Yesso scallop (Patinopecten yessoensis). RESULTS: In a single 454 sequencing run, 805,330 reads were produced and then assembled into 32,590 contigs, with about six-fold sequencing coverage. A total of 25,237 unique protein-coding genes were identified from a variety of developmental stages and adult tissues based on sequence similarities with known proteins. As determined by GO annotation and KEGG pathway mapping, functional annotation of the unigenes recovered diverse biological functions and processes. Transcripts putatively involved in growth, reproduction and stress/immune-response were identified. More than 49,000 single nucleotide polymorphisms (SNPs) and 2,700 simple sequence repeats (SSRs) were also detected. CONCLUSION: Our data provide the most comprehensive transcriptomic resource currently available for P. yessoensis. Candidate genes potentially involved in growth, reproduction, and stress/immunity-response were identified, and are worthy of further investigation. A large number of SNPs and SSRs were also identified and ready for marker development. This resource should lay an important foundation for future genetic or genomic studies on this species

Metabolic suppression in thecosomatous pteropods as an effect of low temperature and hypoxia in the eastern tropical North Pacific

Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Marine Biology 159 (2012): 1955-1967, doi:10.1007/s00227-012-1982-x.Many pteropod species in the eastern tropical north Pacific Ocean migrate vertically each day, transporting organic matter and respiratory carbon below the thermocline. These migrations take species into cold (15-10ºC) hypoxic water (< 20 µmol O2 kg-1) at depth. We measured the vertical distribution, oxygen consumption and ammonia excretion for seven species of pteropod, some of which migrate and some which remain in oxygenated surface waters throughout the day. Within the upper 200 meters of the water column, changes in water temperature result in a ~60-75% reduction in respiration for most species. All three species tested under hypoxic conditions responded to low O2 with an additional ~35-50% reduction in respiratory rate. Combined, low temperature and hypoxia suppress the metabolic rate of pteropods by ~80-90%. These results shed light on the ways in which expanding regions of hypoxia and surface ocean warming may impact pelagic ecology.This work was funded by National Science Foundation grants to K. Wishner and B. Seibel (OCE – 0526502 and OCE – 0851043) and to K. Daly (OCE – 0526545), the University of Rhode Island, and the Rhode Island Experimental Program to Stimulate Competitive Research Fellowship program.2013-06-3

Lack of long-term acclimation in Antarctic encrusting species suggests vulnerability to warming

Marine encrusting communities play vital roles in benthic ecosystems and have major economic implications with regards to biofouling. However, their ability to persist under projected warming scenarios remains poorly understood and is difficult to study under realistic conditions. Here, using heated settlement panel technologies, we show that after 18 months Antarctic encrusting communities do not acclimate to either +1 °C or +2 °C above ambient temperatures. There is significant up-regulation of the cellular stress response in warmed animals, their upper lethal temperatures decline with increasing ambient temperature and population genetic analyses show little evidence of differential survival of genotypes with treatment. By contrast, biofilm bacterial communities show no significant differences in community structure with temperature. Thus, metazoan and bacterial responses differ dramatically, suggesting that ecosystem responses to future climate change are likely to be far more complex than previously anticipated

Seasonal variation in the white muscle biochemical composition of deep-sea macrourids in the North-east Atlantic

The foremost temporal signal to the deep benthos, where temperature and light conditions are relatively constant, is a seasonal pulse of organic carbon sinking from the photic layer. In the Porcupine Seabight region of the NE Atlantic this flux begins during late spring and early summer, although the timing and intensity of the peak varies annually. A rapid response to this nutrient input is most apparent amongst bacteria and benthic meiofauna which can directly utilize the carbon. The question remains as to whether the seasonal influx of carbon to the deep Atlantic may affect, and possibly entrain, aspects of the life cycles of generalist scavengers near the top of the trophic hierarchy, such as macrourid fish. Biochemical analyses of the white muscle of three macrourid species indicate a slight seasonal effect. White muscle protein content in Coryphaenoides rupestris is twofold higher in autumn than spring, RNA content and RNA to protein ratio increased in C. guentheri in autumn, and protein, RNA, and RNA to protein ratio all are higher during autumn than spring in shallow living C. armatus (2,500 m). Changes in RNA to protein ratio in the white muscle of C. armatus, relative to depth of capture, appear to reflect expected patterns in specific growth rate. Significantly higher RNA to protein ratios are apparent in shallow than deep living C. armatus in both seasons. There is no significant decline in white muscle protein content with depth of capture in these three taxonomically related species. Data were collected over several successive years and the possibility of interannual variability complicates the interpretation of seasonal patterns. Despite these limitations this study does indicate a slight seasonal difference in the growth rate of C. rupestris, C. guentheri and C. armatus in the deep Northeast Atlantic

Life in the freezer: protein metabolism in Antarctic fish.

Whole-animal, in vivo protein metabolism rates have been reported in temperate and tropical, but not Antarctic fish. Growth in Antarctic species is generally slower than lower latitude species. Protein metabolism data for Antarctic invertebrates show low rates of protein synthesis and unusually high rates of protein degradation. Additionally, in Antarctic fish, increasing evidence suggests a lower frequency of successful folding of nascent proteins and reduced protein stability. This study reports the first whole-animal protein metabolism data for an Antarctic fish. Groups of Antarctic, Harpagifer antarcticus, and temperate, Lipophrys pholis, fish were acclimatized to a range of overlapping water temperatures and food consumption, whole-animal growth and protein metabolism measured. The rates of protein synthesis and growth in Antarctic, but not temperate fish, were relatively insensitive to temperature and were significantly lower in H. antarcticus at 3°C than in L. pholis. Protein degradation was independent of temperature in H. antarcticus and not significantly different to L. pholis at 3°C, while protein synthesis retention efficiency was significantly higher in L. pholis than H. antarcticus at 3°C. These results suggest Antarctic fish degrade a significantly larger proportion of synthesized protein than temperate fish, with fundamental energetic implications for growth at low temperatures

The HSP70 heat shock response in the Antarctic fish Harpagifer antarcticus.

Members of the HSP70 gene family comprising the constitutive (HSC70) and inducible (HSP70) genes, plus GRP78 (Glucose-regulated protein 78 kDa) were surveyed for expression levels via Q-PCR after both an acute 2-h heat shock experiment and a time course assay in the Antarctic plunderfish Harpagifer antarcticus. In general, down regulation of all genes was observed during the course of the heat shock experiments. This thermally induced down regulation was particularly acute for the GRP78 gene, which at one time point was more than 100-fold down regulated. These results demonstrate the loss of the heat shock response in H. antarcticus, a basal member of the Notothenioidei. This finding is discussed with reference to the survival of Notothenioids during observed ocean warming and also the reorganisation of cellular protein mechanisms of species living in extreme environments

Roman barrows and their landscape context: a GIS case study at Bartlow, Cambridgeshire

This paper examines the landscape context of the Bartlow Hills, a group of large Romano-British barrows that were excavated in the 1840s but have been largely neglected since. GIS is employed to test whether it was possible to view the mounds from nearby roads, barrows and villas. Existing research on provincial barrows, and especially their landscape context, and some recent relevant applications of GIS are reviewed. We argue that barrows are active and symbolically charged statements about power and identity. The most striking pattern to emerge from the GIS analysis is a focus on display to a local rather than a transient audience