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Mid-tidal levels on Hong Kong's exposed shores are dominated by sessile barnacles (Tetraclita squamosa) and mussels (Septifer virgatus). Such shores experience dramatic elevations in air and rock temperatures in mid summer that have been causally linked to mortalities of these species. Tetraclita squamosa and S. virgatus had lower body temperatures relative to their rock substratum. Mussel inhabitants of high- and low-zoned pools were in temperature equilibrium with contained water. On the rocks, body temperatures of T. squamosa were higher than those of S. virgatus. Middle shore individuals had higher body temperatures than lower shore ones. Individuals in the sun had higher body temperatures than those in the shade. Factors possibly affecting body temperature are orientation to the incident sunlight, height on the shore and the contact area between the individual and the substratum. Mean heat coma temperature (HCT) values for submerged Septifer virgatus were 45.0dC and 44.5dC for individuals of between 10-20mm and 30-50mm shell length, respectively. Mean median lethal temperature (LT50) values for submerged S. virgatus were the same for both size classes (47.0dC). A longer exposure in air resulted in a lower LT50 value; a shorter exposure in air resulted in a higher LT50 value. Water content of Septifer virgatus was between 89.21–90.26%, i.e. including the water from the mantle cavity. In air temperatures of between 30–32dC and after long periods of exposure, Septifer virgatus showed significant water loss, i.e. of between 13.87-15.52% body water content. In air temperatures of between 33–36dC and after relatively short exposures, Septifer virgatus showed small water losses, i.e. between 1.92-5.74% body water content. On Hong Kong's exposed rocky shores, sessile components of the middle shore environment are thermally stressed in summer when low tides occur in the afternoon in combination with periods of cloudless sunny days and when rock temperatures may climb to ≅ 50dC through solar insolation. Lower-zoned individuals and high-zoned pool residents are buffered from the adverse effects of such environmental extremes. Mortality occurred mainly in the sun-exposed shore populations of both Tetraclita squamosa and Septifer virgatus and is particularly evident when the above combination of climatic and tidal factors first occurs in July.

This paper reviews the sparse literature on Hong Kong's scleractinian coral communities and explains, in terms of a locally complex climate and hydrography, the broad aspects of their distribution. Corals are restricted to the less polluted, oceanic, eastern waters of Hong Kong and are most diverse in the middle reaches of protected bays from CD to ∼ −10 m CD. Historical evidence suggests that local corals were once more widely distributed but that the settlement of Hong Kong, particularly since its colonization in 1841, has progressively restricted them. Coral collection for lime burning was common until World War II, but has since stopped. Local coral communities, therefore, started anew some 50 yr ago. In recent years, the economic development of Hong Kong has, through uncontrolled pollution, destroyed many coral areas, notably in Tolo Harbour. Today, construction of the new Chek Lap Kok airport and associated infrastructure, requires the dredging of >500 million m3 of marine sands. Dredging operations in eastern waters have destroyed coral communities, through silt suffocation. Other reclamations and borrow areas have also adversely affected corals. Legislation is being drafted and plans are being developed to create marine parks and reserves in Hong Kong. The proposed marine park at Hoi Ha Wan is to try and protect a local coral community. The proposed marine reserve at Cape d'Aguilar is also a coral area within the framework of a more wave-dynamic habitat. Existing legislation has not hitherto protected Hong Kong's corals. The proposed legislation may help, but the reality is that only remnants of what once must have been a spectacular coral community may survive in the territory's remotest bays.

Ergalatax junionae is a muricid gastropod endemic to the Persian Gulf and Gulf of Oman. Following a coral bleaching event in the Persian Gulf in 2007, E. junionae was observed feeding in large numbers on local corals, notably species of Porites and Platygyra . Hitherto, it was unknown what E. junionae fed on but it is not known if this is a record of an opportunistic event or if this muricid is a corallivore as with some congeners.

The calcareous substratum borer, Lithopaga aristata Dillwyn, 1817, secretes posterior incrustations that take the form of interlocking ‘forceps’. These are secreted, initially, as asymmetrical ridges by similarly asymmetrical dorsal and ventral glands in the left and right middle folds of the posterior mantle lobes. In the adult, the secretions are more uniformly spread over the posterior shell margins, concealing the juvenile ridges. Opening and closing of the valves smooths the outer surfaces of the ‘forceps’ against the burrow wall, which also comes to be lined with calcium carbonate that is reciprocally smoothed, so that they occlude the borehole more effectively. Extension and retraction of the siphons probably smooths the inner surfaces of the ‘forceps’ which are sharpened by abrasion, one against the other, during valve opening and closing. The pair of inequilateral spikes so produced, project from the burrow aperture, occluding it, but probably, more importantly, distancing aperturally attacking predators from the true posterior shell margin. Interlocking of the ‘forceps’ and their sharpness may further deter would-be predators.

Juvenile horseshoe crabs, Tachypleus tridentatus and Carcinoscorpius rotundicauda, with prosomal widths of between 11.5 and 102.5 mm, occur along Hong Kong's northwestern shoreline abutting Deep Bay where dissolved oxygen (DO) has been identified as the principal factor determining distribution and survival. Unreported upon hitherto, however, Tachypleus tridentatus occurred consistently in association with sea-grass (Halophila beccarii) beds, with DO concentrations of 8–14 mg·L−1, a median grain size of >180 μm, interstitial water contents of

Over a 52-month period beginning in May 2004 and concluding in August 2008, and coinciding with the period over which TBT was banned as a ship anti-foulant globally, a population of the dogwhelk, Nucella lapillus, was studied for changes in population size and structure, and reproduction. During the study period, the size of the population of N. lapillus on the Mewsbrook Groyne at Littlehampton on the southeastern coast of England grew from approximately 25 individuals to500, i.e., a 20-fold increase. Similarly, population structure normalised to reveal a maximum age of up to approximately 3 years. The numbers of egg capsules produced by the N. lapillus population also grew over the study, again by a factor of 20, and the length of the breeding season increased from 7 months in 2004-2005 and 2005-2006 to 11 months in 2006-2007 and 2007-2008. Such changes were reflected in the incidence of imposex from Vas Deferens Index Stages 3 and 4 in 2003 to zero commencing in 2008 and continuing into 2009. Due to a lack of confirmatory chemical data, the changes in population size, structure and reproduction herein reported upon for N. lapillus cannot be correlated positively with changes in ambient TBT levels, but they can and are correlated with freedom from imposex. This is the first time such a dramatic recovery from imposex, following the banning of TBT, has been documented.

Previous local studies estimated that the densities of emerged, feeding, juvenile Tachypleus tridentatus (prosomal width = 17.1–36.9 mm), obtained from surface counts at Ha Pak Nai, Hong Kong, varied from 4 individuals·1,000 m–2 in summer (July–September) to 0 individuals·1,000 m–2 in winter (December) 2002. To determine if such figures reflected true densities, juveniles were kept in tanks with sediment from the nursery ground at temperatures of between 15–20°C (winter) and 25–30°C (summer) under simulated tidal cycles. After a week's acclimation, their emergences were recorded, as was the depth of sediment to which they burrowed. No individuals emerged under imitated conditions of low tide at winter temperatures whereas 23% emerged at summer ones, indicating that sediment temperatures override circatidal activities when they fall below 20°C. The estimated abundance of juveniles on a nursery beach in the summer of 2002 should therefore be 4.16/0.23 = 18 individuals·1,000 m–2. During the imitated low tide, nearly all juveniles, which did not emerge at the substratum surface, buried themselves to a depth of

The expression of sexuality, overall sex ratio and variation in sex ratio with age of 14 southern Chinese freshwater, brackish and marine bivalves have been investigated. Freshwater species are often hermaphroditic and brooding, e.g. Musculium and Pisidium (Pisidiidae), while Corbicula fluminea (Corbiculidae) demonstrates wide intraspecific variability in sexual expression, but also broods. Anodontu woodiunu (Unionidae) and Limnoperna fortunei (Mytilidae) are dioecious, with low incidence of hermaphrodites in the former, but both have strong female-biased overall sex ratio which does not change with age. Juvenile age classes of Corbicula cf. fluminalis have female-biased sex ratio. A pronounced female bias is means to optimize reproductive success, by maximizing resource allocation into more energy-demanding oogenesis, in temporally and spatially heterogeneous lacustrine habitats. In such habitats, moreover, there are probably diminishing returns to producing sons. Mangrove and brackish water species are all dioecious (except Succostrea cuculluta) with slight male-biased sex ratio overall, but are strongly male-biased as juveniles. This strategy similarly optimizes success in fluctuating intertidal environment, where high rates of juvenile mortality may be expected possibly, for example, through enhanced predation. In such case, therefore, the greater investment in sons is prerequisite to an overall balanced sex ratio. The marine intertidal species, Perna ciridis (Mytilidae) and Donax semigranosus (Donacidae) have stable I:I sex ratio, notvvarying with age, and are representative of the ‘typical’ dioecious condition recorded for most marine bivalves. Thus, although intraspecific variations in life history tactics and sexual strategies equip all species for variable environment, it is postulated that permutations of the ‘dioecious’ condition, mediated through variations in the sex ratio either overall or with age, broadly equip the Bivalvia for the total range of aquatic habitats.

Sixteen species of ahermatypic scleractinian corals have been collected from two submarine caves in Hong Kong. These are Ballanophyllia eguchii, B. ponderosa, Dendrophyllia arbuscula, D. ehrenbergiana, D. coccinea, D. compressa, D. gracilis, Turbastrea coccinea, T. faulkneri, T. diaphana, T. sibogae, T. turbinata, Cyathellia axillaris, Culicia japonica, C. rubeola and Oulangia stokesiana. Eleven of the species are new records for Hong Kong. This study has thus obtained the most diverse collection of ahermatypic corals from Hong Kong hitherto. None of the corals is a cave endemic, however, all being widely distributed in the Indo‐West Pacific. Nevertheless, such cave habitats may be locally important for ahermatypic corals and it is recommended that they be designated as Sites of Special Scientific Interest and possibly receive wider protection under the Marine Parks Ordinance (1995).

Lam, Katherine, Leung, Albert W.Y., Morton, Brian, Hodgson, Paul (2008): A checklist of fish species identified from Conic Island Cave, Hong Kong. Journal of Natural History 42 (9-12): 967-970, DOI: 10.1080/00222930701850620, URL: http://dx.doi.org/10.1080/00222930701850620

Les caracteristiques comportementales et physiologiques de 2 Gastropodes necrophages differant par leur taille et leur habitat sont compris: la temperature et la salinite lethales sont determinees ainsi que leur tolerance a la dessiccation et le jeune alimentaire

Etude du type de proie de P.o. de leurs caracteristiques, et du taux de consommation de ces proies

Hexaplex trunculus is one of the most widespread Mediterranean species of muricid gastropod and lives on rocky, sandy-muddy and mud substrata. Although common in the Adriatic Sea, relatively little is known about its ecology especially its feeding behaviour. The aim of this study was to explore aspects of the feeding behaviour of H. trunculus using Arca noae, Modiolus barbatus and Mytilus galloprovincialis as experimental prey. Prey species preference, predator size, prey size choice, feeding rates, handling times and mode and place of attack were analysed. Typically, only M. galloprovincialis was attacked: A. noae rarely at the byssal gape and M. barbatus never. Small (40 mm) H. trunculus could not easily attack large M. galloprovincialis (65 mm) and preferred small (20 mm) and medium (35 mm) sized prey. Conversely, medium (55 mm) and large (70 mm) H. trunculus fed randomly on M. galloprovincialis of all three sizes. The feeding strategy adopted by the H. trunculus individuals varied with respect to size. A tendency to drill the prey shell was recorded for small individuals whereas marginal chipping was adopted more frequently by large predators. Average small, medium and large H. trunculus consumed 2.4 &plusmn ; ; ; ; 1.6 (range 0 - 4), 1.2 &plusmn ; ; ; ; 1.6 (range 0 - 4) and 2.0 &plusmn ; ; ; ; 2.1 (range 0 - 6) M. galloprovincialis, respectively. There was a statistically significant difference in prey handling time with respect to method of access adopted, predator size and prey size. The time required to access a M. galloprovincialis individual by marginal chipping was considerably less than the time required for drilling. Hexaplex trunculus consumed an average of 0.42 &plusmn ; ; ; ; 0.72 g M. galloprovincialis tissue dry weight over five week period, suggesting that a single individual would, over a period of five weeks, consumed ~40% of its own tissue body weight (this sentence might have to go out depending on changes we make in results). Hexaplex trunculus showed no preference to drill either the left or right valves of M. galloprovincialis but generally attacked the posterior shell margin.

In Henry James's short story "The Middle Years," an ailing writer is troubled by the conviction that only now, after many books, has he begun to find his true voice. All the work he's done so far has been nothing more than a sort of apprenticeship, in preparation for the truly great work that he'll be able to do if only he is granted more time. In the story's last pages, the writer comes to accept the fact that he's dying. He won't get more time. The magnificent works that he might have written will never be written. What he has done already is all he'll ever do. The story isn't depressing, because in his last days, the writer meets an admirer, a young doctor who has read all of his books with an intelligent appreciation. The young man's devotion, a devotion that verges on the idolatrous, helps the writer understand that his life hasn't been in vain. "The thing is to touch someone, to make someone care," the writer says to his admirer. "You happen to be crazy, of course, but that doesn't affect the general law." Near the end of the story, the writer sums up what he's learned: "A second chance! That's the delusion. There never was to be but one. We work in the dark—we do what we can—we give what we have. Our doubt is our passion and our passion is our task. The rest is the madness of art."

Two sympatric species of Platygyra have been identified from Hong Kong waters: i.e., P. sinensis and P. pini. The former has been further subdivided into 4 morphotypes based on colony growth form as follows: classic, encrusting, hillocky, and long-valley. Taxonomic confusion raised by overlapping morphological variations and frequent sympatric occurrences, however, has posed problems in relation to Platygyra ecology and population dynamics. This study attempted to differentiate Platygyra pini and morphotypes of P. sinensis by both morphological and ITS1, 5.8S, and partial ITS2 ribosomal DNA sequence analysis. Morphological data based on 9 skeletal characters were subjected to multivariate analysis. No clear groupings were obtained using a multidimensional scaling plot. Most parsimony analysis was conducted using either the rDNA data set including ITS1, 5.8S, and partial ITS2 or the ITS1 region only. Maximum parsimony (MP) and neighbor-joining (NJ) trees obtained from both data sets, clustered samples of P. sinensis and P. pini into 2 clades. The interspecific Kimura 2-parameter sequence divergence value (k2) obtained by the former rDNA data set was 14.275 +/- 0.507%, which is greater than the intraspecific values (1.239 +/- 1.147% for P. sinensis and 0.469 +/- 0.364% for P. pini), indicating that this marker of ITS1, 5.8S, and ITS2 contains substantially high levels of inherent diversity and is useful in resolving the problematic taxonomy of Platygyra.

The influence of diet on comparative metal accumulation was investigated using a predatory muricid gastropod Thais clavigera. Individuals were fed for up to 56 days on either barnacles, i.e., Tetraclita squamosa, or mussels, i.e., Perna viridis, collected from metal-contaminated and clean sites. Barnacles and mussels have contrasting metal handling strategies and, therefore, different body concentrations, intracellular distributions and detoxification systems. Field collection of prey items that accumulated body metal concentrations over a lifetime of exposure allowed bioavailability to the predator, T. clavigera, to be assessed naturally, which may not be the case for prey exposed to metals for a short time in the laboratory. T. clavigera that was fed cadmium- and copper-contaminated barnacles or mussels ingested significantly greater amounts compared to those fed conspecifics collected from clean locations. T. clavigera body cadmium and copper concentrations were not, however, significantly different between individuals fed either contaminated or clean prey. Amount of zinc ingested was similar in mussels collected from clean and contaminated environments but much less when compared to the barnacle prey. The body concentrations of zinc in T. clavigera fed mussels collected from both sites fell. In contrast, the amount of zinc ingested from barnacle prey was significantly greater from those collected from the metal-contaminated site as compared to the clean one. This was reflected as significantly greater body zinc concentrations in T. clavigera fed contaminated barnacles compared to those fed clean individuals. Copper and zinc accumulation from prey was, therefore, complex. It varied between metal and between prey type, but appeared to be related to the amount ingested and the metal handling strategy of the prey.