bluuebunny/crossref_metadata_2025 huggingface dataset:
Generation and decay of hydrogen peroxide in estuarine waters
Authors: Szymczak R , Waite TD
Published: November 2005

Apart from its central role in photosynthesis, one of the most dramatic effects of light in marine and freshwater systems is its ability to generate reactive chemical intermediates. Of these, hydrogen peroxide is one of the more stable and easily detected. Aspects of the generation and decay of hydrogen peroxide in the Port Hacking River estuary, New South Wales, have been investigated in a number of field and laboratory studies. Peroxide concentrations in surface waters in the early morning are relatively uniform over the estuary and typically less than 35 nM, whereas concentrations in mid-afternoon in excess of 100 nM have been observed. Variation of peroxide concentration with depth in the deep basins of Port Hacking is dependent on the extent of structure within the water column, with little mixing of surface- generated peroxide into poorly-illuminated bottom waters under stratified conditions. Laboratory studies confirmed that light induces the production of hydrogen peroxide, the initial rate of production increasing with increasing molar absorptivity of the filtered water sample. Filtration of samples had little effect on the generation of hydrogen peroxide but dramatically reduced the rate of decay of photogenerated hydrogen peroxide.
Fish predators of the western rock lobster (Panulirus cygnus George) in a nearshore nursery habitat
Authors: Howard RK
Published: November 2005

Nearshore limestone reefs of Western Australia represent an important nursery habitat for juveniles of the western rock lobster (Panulirus cygnus). As part of a trophic study of the fish community associated with these reefs, fishes were examined for evidence of predation on western rock lobsters. Six fish species were found to have ingested P. cygnus. Of these, Psammaperca waigiensis (sand bass), Pelsartia humeralis (sea trumpeter), Pseudolabris parilis (brown-spotted wrasse) and Plectorhyncus flavornaculatus (gold-spotted sweetlips) were among the ten most abundant fish in gill-net collections from the study site. P. cygnus formed a significant portion of the diet of P. waigiensis, but was < 5% of the dietary volume of other species. Predation occurred at all times of the day and was concentrated on small, newly-settled P. cygnus (8-15 mm carapace length). The vulnerability of lobsters to predation appears to be strongly related to size, and the cryptic habits that are unique to newly-settled stages can be explained in terms of the risks of predation. Assessment of the proportion of mortality of P. cygnus due to predation is hampered by a current lack of information on the natural densities of both fishes and small rock lobsters. However, conservative estimates indicate that an annual removal by fish of thousands of lobsters per hectare is likely, suggesting that predation is a major factor affecting the survival of P. cygnus on nursery reefs.
Lipids as indicators of the origin of organic matter in fine marine particulate matter
Authors: Currie BR , Johns RB
Published: November 2005

The lipid compositions of fine particulate matter (<35 �m diameter) have been analysed from two temperate sites (Western Port Bay, WPB, and Corner Inlet, CI, Victoria) and two tropical sites (Bowling Green Bay, BGB, and Lizard Island Lagoon, LIL, North Queensland) in the Australian coastal zone. Identification of lipid biomarker molecules (especially fatty acids, fatty alcohols and sterols) has, in conjunction with microscopy, enabled identification and, in some instances, quantification of a range of biological inputs. Estimated contributions of biomass to total particulate mass in the temperate samples were: seagrass detritus (~10-15%) > bacteria (~34%) > live diatoms (≤ 1%). Similar estimations for the tropical samples were: BGB, bacteria (- 1%) > live diatoms (< 1%); and LIL, bacteria (~20-30%) > copepod detritus (≥ 1%) > live diatoms (< 1 %). Biomarkers also indicated the presence of coral mucus and a distinctive bacterial chemotype, possessing branched chain alcohols, in the LIL sample.
Kestratherina brevirostris, a new genus and species of silverside (Pisces : Atherinidae) with a review of atherinid marine and estuarine genera of southern Australia
Authors: Pavlov A , Ivantsoff W , Last PR , Crowley LELM
Published: November 2005

The systematics of southern Australian marine and estuarine atherinids has been confused by the many generic name changes since Richardson first described Atherina hepsetoides in 1843. Recent studies have shown that Atherinason esox (Klunzinger 1872) comprises two distinct species. Further studies using electrophoretic techniques have also shown that these two species belong in a new genus rather than in the genus Atherinason. The new genus Kestratherina will therefore include K. esox and a new species, K. brevirostris. Electrophoresis has also shown that Atherinosoma is not a cohesive group, and the two species originally assigned to that genus, A. presbyteroides (Richardson 1843) and A. wallacei, Prince, Ivantsoff and Potter 1982, must be placed into a new genus, Leptatherina.seagrass detritus, phytoplankton, diatoms, bacteria, zooplankton, fatty acids, sterols,
fatty alcohols.
Abundance, Diet and predators of juvenile banana prawns, Penaeus merguiensis, in a tropical mangrove estuary
Authors: Robertson AI
Published: November 2005

Sampling of Penaeus merguiensis de Man with a variety of nets in several microhabitats of a small mangrove-lined estuary near Townsville on seven occasions during 1985 and 1986 captured only one adult prawn. Juveniles of 1-21 mm carapace length (CL) entered the mangrove forest at high tide throughout the year in concentrations up to 0.45 m-3. The mean density of juveniles (3-23 mm CL) in small creeks, which drain into the mainstream of the estuary, was highest in April (41 m-2) and lowest in August (0.3 m-2). The diet of prawns varied with size and microhabitat within the estuary. In creeks, flocculent detrital material (FD) composed of organic aggregates, but without recognizable mangrove detritus, was the most important food item for three size groups of prawns. However, the importance of FD decreased with prawn size as did the proportions of small prey such as diatoms, ostracods and harpacticoid copepods in the diet. The importance of recognizable mangrove detritus increased with prawn size, but never made up more than 15% of the volume of the diet. Insects, mainly dipteran larvae and ants, were 15% of the dietary volume of medium sized prawns (11-15 mm CL) in creeks. On shallow banks on the edge of the maintstream of the estuary, prawns consumed more animal tissue than detritus, and polychaetes and fragments of large crustaceans were important items in the diet. Seven of the 122 species of fish captured in the estuary consumed P. merguiensis. Young barramundi, Lates calcarifer (Bloch), (30-50 cm total length) were the most important predators on juvenile P. merguiensis, with prawns making up 22% by volume of their diets. The possible causes of the link between juvenile P. merguiensis and mangroves are discussed.
Taxononmic and ecological studies of ciliates from Australian saline soils: colpodids and hymenostomate ciliates
Authors: Pomp R , Wilbert N
Published: November 2005

A total of 27 ciliate species was found in samples of alkaline soils from arid regions in southern Australia. Seven of them are described and illustrated, three for the first time: Spathidium metabolicum, sp. nov., Sagittaria australis, sp. nov, and Cinetochilum rnarinum, sp. nov. The morphogenesis of Homalogastra setosa Kahl and Pseudocohnilembus persalinus Thompson & Evans is described. Critical taxonomic featues are clarified.
Sea-level fluctuations and the distributions of some freshwater crayfishes of the genus Engaeus (Decapoda; Parastacidae) in the Bass Strait
Authors: Horwitz P
Published: November 2005

The effect of past sea-level fluctuations on the distribution of one species of freshwater crayfish, Engaeus cunicularius, which occurs in coastal areas on both sides of Bass Strait and on several Bass Strait islands, is discussed. A model is proposed to explain the way in which successive rising and falling of sea levels has contributed to the distributions and speciation of some species in the genus Engaeus, and the implications of the model are outlined. Bass Strait is not considered to have acted as a complete barrier to freshwater organisms during periods of lowered sea levels.
Effects of zooplankton grazing on phytoplankton communities in Mt Bold Reservoir, South Australia, using enclosures
Authors: Merrick CJ , Ganf GG
Published: November 2005

Enclosure experiments demonstrated that zooplankton grazing changed the composition of the phytoplankton community in Mt Bold Reservoir. Phytoplankton biomass as measured by chlorophyll a did not change within the enclosures but changed across the experiments in response to zooplankton grazing. The chlorophyll a : phaeophytin a ratio did not reflect zooplankton grazing activity. Phytoplankton species richness and diversity did not change but the frequencies of many individual phytoplankton taxa differed in response to zooplankton grazing. Neither taxonomic identity nor phytoplankton size as measured by greatest axial linear dimension and volume determined the susceptibility of a taxon to grazing. This suggests that other criteria are important in food selection, criteria which vary between experiments. Multivariate statistical techniques successfully differentiated the grazed and the ungrazed phytoplankton communities based on the different frequencies of the component taxa. There was an indication that, within the enclosures, zooplankton grazing advanced the phytoplankton community along a temporal path. Microzooplankton grazing was not examined in these experiments but there was evidence that it was significant.
Limnology of oligotrophic dune lakes at Cape Flattery, North Queensland
Authors: Hawkins PR , Taplin LE , Duivenvoorden LJ , Scott F
Published: November 2005

Physical, chemical and biotic attributes of 16 lakes and ponds in the siliceous dunefields of Cape Flattery, in the humid tropics of Australia, have been investigated. The dune lakes are similar to those of dunefields in south-eastern Queensland, with very low to low conductivity (62-338 �S cm-1), low pH (3.9-6.8), and low to high humic content (gilvin 0.0-31.0 g440 m-1). These lakes are apparently not perched above the local water table. The ionic compositions of all lakes were very similar, with NaCl predominating and with very low concentrations of Mg, Ca, K, and SO4. Bicarbonate was absent or negligible in most lakes. The oligotrophic lakes are characterized by a desmid-diatom limnetic plankton of moderate diversity (12-35 species per lake). Of 144 taxa of phytoplankton recognized, 58% were desmids and 15% diatoms. The zooplankton was of low diversity and dominated by Calamoecia ultima. Twenty-nine species of aquatic macrophytes and 11 species of fish were recorded. Freshwater turtles (possibly Chelodina rugosa Ogilby), and the estuarine crocodile, Crocodylus porosus Schneider, were recorded from some lakes. Principal component analysis of chemical data distinguished three groups of lakes: a series of humic-stained ponds and lakes, a group of clear-water lakes with little or no humic staining, and a former barrier lagoon. Cluster analysis of the phytoplankton flora consistently segregated the clear-water lakes from humic-stained lakes but, in general, concordance of chemical, physiographic and biotic characteristics was poor. Existing classification schemes for Australian dune lakes, based on similar sets of physiographic, chemical and biotic data, do not cater well for the Cape Flattery lakes. A more useful classification may derive from consideration of the hydrological processes influencing their water balance and chemical characteristics.
Feeding energetics and angling catches of spangled perch, Leiopotherapon unicolor (Günther 1859), (Percoidei : Teraponidae)
Authors: Gehrke PC
Published: November 2005

Spangled perch, Leiopotherapon unicolor, in aquaria reduced their daily ration as water temperature decreased. Fish held at a mean temperature of 16.8�C did not grow significantly over a period of 180 days, whereas individuals maintained near 22.6�C showed a weight increase of 32.8% over the same period. Both groups of fish metabolized approximately 38% of their energy intake, excreted 57% and allocated 5% for growth. Fish adapted to the lower temperature regime consumed 10.81 kJ day-1 compared with a predicted value of 2.08 kJ day-1 for fish adapted to warmer temperatures and exposed to 16.8�C. Spangled perch appear to repartition energy resources at some point below 16�C to make up for a shortfall in energy intake caused by reduced ration. Fish in their natural environment may also reduce food intake at low temperatures, as spangled perch caught by angling in winter had less food in their stomachs (0.31% body weight) than fish caught in other seasons (4.87% in spring to 3.13% in autumn). Catch rate in winter (< 1 fish per angler hour) was also lower than that in other seasons (> 5 fish per angler hour).
Monthly mean surface thermal structure in the Tasman Sea from satellite imagery, 1979-84
Authors: Tate PM
Published: November 2005

The use of satellite data provides a far greater density and more uniform distribution of observations than the more classical modes of oceanographic data collection. By sacrificing some spatial resolution of the satellite data, it is possible to retrieve sea surface temperatures on a global basis that have absolute accuracies within 1�C of drifting buoy data. Five years of low resolution infra-red data from the United States' National Oceanic and Atmospheric Administration satellites have been analysed for the area of the Tasman and Southern Coral Seas. Monthly mean surface thermal patterns compare favourably with previous studies using Merchant Ship data. In the western Tasman Sea the East Australian Current can be clearly seen throughout the year, although the more transitory eddies often associated with the current system are not apparent. General circulation patterns off the west coast of the South Island of New Zealand show severe bending of the isotherms to the south. The nature of the surface thermal signal of the Tasman Front is quite different either side of the Lord Howe Rise and there is some doubt whether these two features are linked.
Juvenile sex inversion in the New Zealand snapper Chrysophrys auratus (Bloch and Schneider, 1801) (Sparidae)
Authors: Francis MP , Pankhurst NW
Published: November 2005

Gonads from snapper of age classes 0+ to 10+ years sampled from the north-east coast of New Zealand were examined histologically for evidence of sex inversion. All 0+ fish were undifferentiated, and all 1 + fish were immature females. 2+ to 4+ fish had gonads that were either ovary, ovo-testis or testis. Older fish were either male or female. Snapper reach sexual maturity at ages of 2-5 years, so the developmental pattern is one of juvenile sex inversion by some of the population, and functional gonochorism.
Genetic variation, breeding structure and taxonomic status of the gummy shark Mustelus antarcticus in southern Australian waters
Authors: MacDonald CM
Published: November 2005

Electrophoretic studies of the protein products of 32 presumed gene loci have indicated low levels of allelic variation in Mustelus antarcticus. Only one enzyme, L-lactate dehydrogenase (LDH), exhibited sufficient allelic polymorphism to be useful as a marker for population studies. The distribution of LDH alleles was homogeneous in M. antarcticus sample sets collected from across the range of the species. The LDH data, together with information from earlier tagging studies, suggest that there is sufficient movement and gene exchange for M. antarcticus throughout southern Australian waters to be considered part of a single breeding population. The high degree of genetic similarity observed between all samples also indicates that there is only one Mustelus species (M. antarcticus) in southern Australian waters.
Distribution and abundance of marine birds in the Eastern Indian Ocean
Authors: Dunlop JN , Wooller RD , Cheshire NG
Published: November 2005

A survey of pelagic seabird distribution in the eastern Indian Ocean was conducted during October 1987. Five seabird assemblages were identified, associated with different marine environments. Sea surface salinity appeared to be the most important factor in tropical, oceanic waters and sea surface temperature in shelf waters. A distinct and relatively species-rich community occurred over the South Equatorial Current, where seabird biomasses were relatively high, albeit patchily distributed. Overall, the patterns of abundance of pelagic seabirds north-west of Australia reflected the known patterns of nutrient enrichment and marine productivity. There was evidence of some biogeographic commonality in seabirds between the tropical Pacific and eastern Indian Oceans, resulting from a 'throughflow' of water types.
Macroinvertebrate community structure and chemistry of an organically polluted creek in south-east Queensland.
Authors: Cosser PR
Published: November 2005

The benthic macroinvertebrate fauna of Gowrie Creek, south-east Queensland, and 24 chemical and physical parameters were monitored for 105 km downstream from a major sewage effluent outfall between June 1981 and October 1984. Species richness declined to 2-3 taxa while the density of organisms increased significantly immediately below the outfall. A progressive increase in the number of taxa present was evident with distance downstream. The major species associations, progressing downstream from the outfall, were: Chironornus/Tubificidae: Chironornus/Sirnuliurn ornatipes; Plotiopsis balonnensis; and P. balonnensis/Cheurnatopsyche (modica?). The elimination of taxa in the vicinity of the outfall was attributed to the effects of depletion of dissolved oxygen and possibly ammonia toxicity and sulfide toxicity. Changes in dominance were related to the changes in food types associated with a transition from a heterotrophic to an autotrophic environment. The study presents additional data on community structure and species associations characteristic of different degrees of organic pollution.
Comparisons between surface, barotropic and abyssal flows during the passage of a warm-core ring
Authors: Mulern PJ , Filloux JH , Lilley FEM , Bindoff NL , Ferguson IJ
Published: November 2005

A comparison is made of results for barotropic, surface and abyssal flows during the formation and passage of a warm-core ring in the East Australian Current. The barotropic velocities are estimated from sea-floor measurements of the horizontal electric field, which is induced by water motion. Values for the surface and near-bottom velocities are obtained generally by more traditional methods. A strong similarity is observed between the directions of the barotropic and surface flows. At a site close to the foot of the continental slope, the barotropic and near-bottom velocities are also similar, both in direction and magnitude. A possible explanation for this effect is that proximity to the coast constrains flow directions and causes the streamlines at depth to converge on the western (or near-shore) side of the warm-core ring. The determination of barotropic velocities enables barotropic volume transports to be estimated and compared with traditional geostrophic volume transports calculated for water motion between the surface and a depth of 1300 m. The barotropic transports are found to be greater than the geostrophic transports by a factor of approximately 1.6, indicating the significance of deep-water flow in the East Australian Current.
Biology of four species of Whiting (Pisces: Sillaginidae) in Botany Bay, NSW
Authors: Burchmore JJ , Pollard DA , Middleton MJ , Bell JD , Pease BC
Published: November 2005

Four species of whiting (Family Sillaginidae) were collected from Botany Bay, New South Wales, between 1977 and 1979: Sillago ciliata (sand whiting), S. maculata maculata (trumpeter whiting), S. robusta (stout whiting) and S. bassensis flindersi (eastern school whiting). Sillago ciliata was the most abundant species over-all. Sillago ciliata was caught in greatest numbers in Zostera seagrass and shallow sandy habitats, whereas S. m. maculata, S. robusta and S. b. flindersi were most abundant over deeper muddy and sandy habitats. Sillago ciliata and S. b. flindersi were present mainly as juveniles. Gonosomatic indices and gonadal maturity stages of S. ciliata and S. m. maculata peaked around February. These species probably spawn within the Bay. Length to caudal fork at first maturity was 24 cm for male and female S. ciliata, 19 cm for male and female S. m. maculata, 17 cm for male and 18 cm for female S. robusta, and 14 cm for male and female S. b. flindersi. Although all species fed mainly on polychaetes and crustaceans, there was little overlap in specific dietary items between species. Variations observed in diet were due to fish size and temporal and spatial habitat differences within and among species.
Female reproductive biology and spawning periodicity of two species of king prawns, Penaeus longistylus Kubo and Penaeus latisulcatus Kishinouye, form Queensland's East Coast Fishery
Authors: Courtney AJ , Dredge MCL
Published: November 2005

In the coastal region of central Queensland female red-spot king prawns, P. longistylus, and the western or blue-leg king prawns, P. latisulcatus, had high mean ovary weights and high proportions of advanced ovary development during the winter months of July and August of 1985 and 1986. On the basis of insemination, both species began copulating at the size of 26-27 mm CL, but P. longistylus matured and spawned at a smaller size than P. latisulcatus. Abundance of P. longistylus was generally three to four times greater than that of P. latisulcatus but the latter was subject to greater variation in abundance. Low mean ovary weight and low proportions of females with advanced ovaries were associated with the maximum mean bottom sea-water temperature (28.5�C) for both species. Population fecundity indices indicated that peaks in yolk or egg production (a) displayed a similar pattern for both species, (b) varied in timing from year to year for both species and (c) were strongly influenced by abundance. Generally, sample estimates of abundance and commercial catch rates (CPUE) showed similar trends. Differences between the two may have been due to changes in targeted commercial effort in this multi-species fishery.
Observations on the Ultrastracture of Baculovirus in Australian Penaeus monodon and Penaeus merguiensis
Authors: Doubrovsky A , Paynter JL , Sambhi SK , Atherton JG , Lester RJG
Published: November 2005

Baculovirus particles were found in the digestive gland of Penaeus monodon from hatcheries and grow-out ponds in northern New South Wales, northern Queensland and the Northern Territory. Similar particles were seen in a Penaeus merguiensis specimen caught off Townsville, Queensland. The particles were found in the hypertrophied nuclei of hepatopancreatic epithelial cells, both free in the nucleoplasm and occluded in large eosinophilic intranuclear inclusion bodies. The nucleocapsids of the particles measured 45-52 nm × 260-300 nm and resembled the baculovirus reported from Penaeus plebejus.
Seasonal occurrence of Conidia of Aquatic Hyphomycetes (Fungi) in Lees Creek, Australian Capital Territory
Authors: Thomas K , Chilvers GA , Norris RH
Published: November 2005

The aquatic hyphomycete spora of an upland stream (Lees Creek) were sampled twice monthly by membrane filtration at two sites, the upstream one with native riparian vegetation and the downstream one with exotic pines. Physicochemical properties of the water were measured at each sampling. Conidia of 43 species were collected, of which 18 are undescribed and most species occurred at both sites. The peak concentrations of conidia occurred in late summer to early autumn and minimum concentration in winter. This contrasts with the autumn-winter maximum and summer minimum concentrations recorded for tree-lined streams of the Northern Hemisphere. These differences correspond with differences in seasonality of litter fall in the Northern Hemisphere compared with Australia. Analysis of variance showed significant differences between the two sites for concentrations of conidia of individual species and of total conidia. The magnitude of these differences was related to the time of sampling. Using multiple linear regression analysis, the occurrences of conidia detected at the up-stream site were best explained by water temperature; down-stream, rainfall and water temperature together explained most variance.
Seasonal and Inter-annual variability in Chemical and Biological parameters in Storm Bay, Tasmania. I. Physics, Chemistry and the Biomass of components, of the food chain
Authors: Clementson LA , Harris GP , Griffiths FB , Rimmer DW
Published: November 2005

As south-east Tasmania lies close to the subtropical convergence, the waters of the shelf regions are a complex mixture of subtropical and subantarctic water masses. Temperature, salinity and nutrient data from the waters off Maria Island have been recorded for 40 years and show considerable inter-annual variability. In a complementary study, physical, chemical and biological parameters were measured in Storm Bay over 3 years. The enlarged data base gives a detailed picture of the seasonality and inter- annual variability in south-east Tasmanian waters and the effects of such variability on the food chain. The temperature and salinity measurements show that the water in Storm Bay is strongly influenced at different times of the year by water of subtropical origin from the east and by water of subantarctic origin from the west. Satellite images and drift-card data confirm these findings. Chemical parameters (dissolved inorganic and organic nutrients) showed the expected temperate seasonal trends, but some features of the seasonal cycle differed greatly in magnitude and duration between years. Differences between the years are shown to be due to inter-annual differences in the westerly wind stress, which affects nitrate concentration. In years of strong westerlies, the phytoplankton biomass and productivity increases and the spring bloom lasts longer. In such years, zooplankton biomass increases by a factor of ten in late spring, and salps replace euphausiids as the dominant organisms.
Tributyltin in Sydney Harbour and Georges River Waters
Authors: Batley GE , Mann KJ , Brockbank CI , Maltz A
Published: November 2005

Water from 23 sites in Sydney Harbour and the Georges River estuary (N.S.W.) have been analysed for tributyltin (TBT) using gas chromatography with electron capture detection, after solvent extraction as the hydride. Analytical data for TBT in Sydney waters are consistent with other data reported for overseas estuaries, with the majority of samples containing less than 45 ng Sn L-1 as TBT. Samples from areas of high boating activity such as Rushcutters Bay and Garden Island gave the highest TBT concentrations at 90-190 ng Sn L-1. The mean ambient TBT concentration in each estuary was computed using a tidal prism model. Despite the broad assumptions made, calculated results agreed well with those measured at sites with no obvious local point source of TBT.
Accumulation of Tributyltin by the Sydney Rock Oyster, Saccostrea commercialis
Authors: Batley GE , Fuhua C , Brockbank CI , Flegg KJ
Published: November 2005

Tributyltin (TBT) concentrations have been measured in the tissue of the Sydney rock oyster Saccostrea commercialis sampled from estuaries in New South Wales, Australia. Background TBT levels of below 2 ng Sn g-1 contrasted with values between 80 and 130 ng Sn g-1 in oysters exposed to high boat densities or poor tidal flushing. Shell deformities and reduced tissue weights were associated with all samples displaying elevated TBT levels. Specimens of the Pacific oyster, Crassostrea gigas, growing on the same racks displayed 2-3 times the TBT concentrations of S. commercialis.
Seasonal changes in Larval populations of Culicoides subimmaculatus Lee & Reye (Diptera: Ceratopogonidae), with observations on the influence of tides on larval ecology
Authors: Edwards PB
Published: November 2005

At Tingalpa Creek, Brisbane, larvae and pupae of Culicoides subimmaculatus were most numerous 1.94 m above datum, midway between mean high-water neaps and mean high-water springs. Monitoring of a field population of immature stages indicated that C. subimmaculatus completes four generations a year, and overwinters in the 4th larval instar. Adults emerge during synchronized periods associated with the lunar tidal cycle; however laboratory experiments indicated that tidal coverage did not affect the time of adult eclosion or of pupation. It is suggested that synchronization occurs at an earlier point in the life cycle, possibly at ecdysis of 3rd to 4th instars.
Variation in the components of Benthic community structure in a Coastal Lagoon as a function of Spatial Scale
Authors: Hatcher A
Published: November 2005

The perception of community structure is strongly related to the spatial resolution of data collection. To quantify variation in community structure at several spatial scales, the benthos was examined on the limestone substratum in a nearshore coastal lagoon. Community structure was described using a form of pattern analysis called correspondence analysis. Variance at three spatial scales was measured. These scales were described as: (I) between offshore and nearshore reefs (kilometres); (2) among areas on the nearshore reef-line (< 1 km); and (3) between community types on the nearshore reef-line (tens of metres and less). Organisms were classified according to higher taxa/functional classes. Parameters which varied between reef-lines included: (i) community composition determined using multivariate ordination, (ii) cover by calcareous and filamentous algae and (iii) abundance of seagrass and juvenile kelp (Ecklonia radiata). Among the areas on the nearshore reef-line, variance in community composition was due to the distribution of animals. There was a south to north gradient of increasing cover by encrusting animals and abundance of ascidians. Within the areas on the nearshore reef-line, there were two distinct community types characterized by macrophytic plants or sessile invertebrates. The major potential controls of the variation in benthic community structure were different at each of the spatial scales examined. The strong relationships between extrinsic factors and components of the communities suggested that the major potential controls were: (a) exposure to swell at the large scale (between reef-lines), (b) availability of food at the medium scale (within areas on the nearshore reef-line) and (c) biological interactions or responses to microtopography and light climate at the small scale (between and within communities on the nearshore reef-line).
Biology of three hammerhead sharks (Eusphyra blochii, Sphyrna mokarran and S. lewini) from Northern Australia
Authors: Stevens JD , Lyle JM
Published: November 2005

The hammerhead sharks Eusphyra blochii, Sphyrna mokarran and S. lewini form part of the incidental catch of a commercial gill-net fishery off northern Australia. Of the specimens sampled between June 1980 and December 1986, 46% of S. mokarran, 41% of E. blochii and 31% of S. lewini were females. Few adult female S. lewini were caught and it is suggested that these occur offshore of the study area. In northern Australia, the usual size at maturity of male E. blochii, S. lewini and S. mokarran is 108, 150 and 225 cm total length (TL), ,and of females is 120, 200 and 210 cm TL, respectively. S. mokarran and E. blochii gave birth in January and February/March, respectively, after a gestation period of 10-11 months. S. Iewini appears to have a more extended seasonal cycle: the young are born between October and January after 9-10 months gestation. Size at birth is about 45-50 cm TL in E. blochii and S. lewini, and 65 cm TL in S. mokarran. Mean litter size is 12 in E. blochii, 15 in S. mokarran and 17 in S. lewini. Individual E. blochii females breed every year, whereas S. mokarran females probably breed every other year. Fish are an important component of the diet of all three species as, to a lesser extent, are cephalopods for S. lewini and crustaceans for S. mokarran and E. blochii.
Nitrogen fixation (acetylene reduction) in nonheterocystous cyanobacterial mats from the Dampier Archipelago, Western Australia
Authors: Paling EI , McComb AJ , Pate JS
Published: November 2005

Discs punched from non-heterocystous cyanobacterial mats, one containing Microcoleus chthonoplastes, Oscillatoria sp. and Phormidium sp., the other Phorrnidium sp. and Aphanocapsa sp., were incubated for 23 days in artificial sea-water of salinity 0 to 140 g L-1. The chlorophyll a content of both mats increased over this salinity range, with lower increases above 100 g L-1. There was little change in the species composition of mats at salinities 240 g L-1; ≥ 40 g L-1, mats produced essentially monospecific thalli containing small quantities of the other species. Acetylene reduction ranged from zero at the highest salinity to a maximum of 1100-1500 pmol C2H2 reduced m-2 h-1 at 20-60 g L-1. Maximum fixation rates were two orders of magnitude higher than in situ measurements (8-60, mean 16 pmol C2H2 reduced m-2 h-1). The salinity range observed in the field was 40-60 g L-1, but maximum fixation rates in the field (60 Fmol C2H2 reduced m-2 h-1) were much lower than those observed in the laboratory.
Studies on Marteilia sydneyi, agent of QX disease in the Sydney rock oyster, Saccostrea commercialis, with implications for its life cycle
Authors: Roubal FR , Masel J , Lester RJG
Published: November 2005

An indirect fluorescent antibody test (IFAT) was developed to test for mature and immature stages of Marteilia sydneyi in the digestive gland of the Sydney rock oyster, Saccostrea commercialis. Immunogold labelling of sections for electron microscopy showed that the sporont membrane, refringent granules, spore wall and haplosporosomes were particularly antigenic. The antibody did not react with any myxosporidean parasite found in local fish. Large numbers of sporonts were shed by infected oysters before oyster death. Lightly infected oysters were apparently able to shed all of their parasites and recover. Refringent granules were proteinaceous and an unlikely energy source for the shed parasite. Growth of the sporont was associated with the enlargement and production of refringent granules. The findings implicate filter-feeding or detritivorous invertebrates rather than scavenging invertebrates or fish in the life cycle of Marteilia parasites.
Growth, density and biomass of Ecklonia radiata at different depths and growth under artifical shading off Perth, Western Australia.
Authors: Kirkman H
Published: November 2005

The standing crop and density of the kelp Ecklonia radiata (C. Ag.) J. Agardh declined with depth on limestone reefs near the coast off Perth, Western Australia. Some other macroalgae became more abundant. The plant's growth rate was determined monthly at 5 m and 10 m depth over a 16-month period. Annual frond productivity at the 5-m site was 3.5 kg dry wt m-2 year-1, and at the 10-m site, 2 kg dry wt m-2 year-1. Maximum productivity occurred in spring (Sept.-Oct.) at the 5-m site and 2 months later at the 10-m site. The two sites had similar water movement and were assumed to have similar nutrient, salinity and temperature regimes. However, irradiance at 10 m was about 10% of that at the surface, while at 5 m it was about 30%. Artificial shading of the kelp canopy at the 5-m site during winter and autumn reduced productivity to levels similar to those at the 10-m site; this suggests that irradiance may limit kelp growth at these times.
Biology of Leiognathus decorus (Leiognathidae) in Sulaibikhat Bay, Kuwait
Authors: Wright JM
Published: November 2005

During a survey between September 1986 and August 1988 of the fish assemblage in Sulaibikhat Bay, Kuwait, large numbers of Leiognathus decorus were captured in depths between 0.6 and 8.0 m with an otter trawl. Catch size of L. decorus differed markedly between years, a characteristic of seasonal tropical environments that are dominated by small, fast-growing species. L. decorus was not caught in the cold winter months of December and January. Large fish congregated for spawning in the subtidal zone (4 to 8 m depth) in spring (March-April). Young of the year recruited to the intertidal zone (0.6 to 2 m depth) in May and remained until November, returning in February and March as the spawning stock. Smaller fish (< 69 mm) consumed a large proportion of calenoid copepods as well as benthic invertebrates, whereas larger fish consumed almost exclusively benthic invertebrates. Both size groups ate chlorophytes, particularly during a spring bloom.
Growth of the abalone Haliotis roei gray
Authors: Keesing JK , Wells FE
Published: November 2005

The growth characteristics of the abalone Haliotis roei from Western Australia are described. Abalone grow rapidly to over 40 mm in their first year. In their second year, they reach 60 mm, the minimum size that can be legally taken by amateur fishermen. They are recruited to the commercial fishery at 70 mm during their third year. The parameters of the von Bertalanffy growth model were K = 0.67 year-1 and L∞ = 85.2 mm; however, differences occur between intertidal and subtidal habitats, with abalone of the subtidal population achieving faster growth rates and a larger maximum size. No significant differences in growth were detected between sexes.
A multiple regression model for prediction the food consumption of Marine Fish populations
Authors: Palomares ML , Pauly D
Published: November 2005

The construction of trophic (food web) models of ecosystems, as needed for both theoretical and practical purposes such as fisheries management, requires estimates of food consumption (Q) by each of the various species (groups) included in the model. These estimates are usually required on a per-biomass (B) basis, i.e. as estimates of the ratio of the food consumed to the weight of the consumers (Q/B) during a stated period. For estimates of Q/B to be most useful, they must take account of: (i) seasonal fluctuations of food intake; (ii) the age/size structure of the population; and (iii) the type of food consumed. In this study, 33 estimates of Q/B are reviewed, and an empirical multiple regression model for prediction of Q/B is presented which incorporates points (i) to (iii) above. The predictor variables are: (a) the asymptotic weight of the fish of the study population, (b) the aspect ratio of their caudal fin (as a measure of the average activity and/or metabolic levels of the fish), (c) the mean habitat temperature and (d) the food type (a dummy variable, 0 ih,carnivores and 1 in herbivores). The model explains nearly 75% of the variance in the data set used, which includes myctophids and tunas, flatfishes, rabbitfishes, and other groups from both tropical and temperate waters. The implications of this model for bioenergetics are discussed, along with its future extension, to be based on a much larger data set.
Pleopod cuticular morphology as an index of moult stage in the ornate Rock Lobster, Panulirus ornatus (Fabricius 1789)
Authors: Turnbull CT
Published: November 2005

Seven discrete stages and substages of moulting in the ornate rock lobster, Panulirus ornatus, have been distinguished by microscopic examination of the cuticle and setae of the pleopods. The diagnostic features and the duration of each of the stages are described. Freezing did not visually alter the tissue features used to identify each moult stage. Pleopod morphology can reliably indicate whether a lobster has moulted within the previous 24 h or is within 72 h of the next ecdysis.
Feeding ecology of Haloniscus earlei chilton, and Oniscoid Isopod living in Athalassic Saline Waters
Authors: Blinn DW , Blinn SL , Bayly IAE
Published: November 2005

Densities of the oniscoid isopod, Haloniscus searlei Chilton, were orders of magnitude higher on solid substrata than on sediment in the athalassic saline waters of Lake Keilambete and Lake Corangamite, Victoria, Australia. The feeding ecology of H. searlei was examined in the laboratory. Three different grazing densities were employed; one was similar to the estimated density of Haloniscus in the field (c. 212 individuals per m² siderite substratum), and the other two were 3 and 5.5 times higher than field densities, respectively. It was concluded that H. searlei was a very effective grazer. After 2 weeks, treatments with the highest grazing density had 2.5 times less periphyton biomass than treatments at the lowest grazing density and over 3-fold less periphyton than ungrazed controls. Estimated consumption-index values for periphyton were 0.206, 0.124, and 0.096 for treatments ranging from low to high grazing densities. Diatom community structure remained the same in all grazing treatments after 2 weeks. The ability of Haloniscus to use Tanytarsus larvae for food was examined. Cannibalism was also noted.
A hydrological regionalization of streams in Victoria, Australia, with implications for stream Ecology
Authors: Hughes JMR , James B
Published: November 2005

Annual, monthly, low and peak flow data were used to classify and ordinate 138 stream gauges in Victoria. Sixteen hydrological variables were used and low-flow and entire-flow regionalizations were derived. The low-flow regionalization was spatially indistinct and therefore unusable, but the entire-flow regionalization produced five distinctive and spatially significant regions. Least-squares relationships were calculated between mean annual runoff, catchment area and coefficient of variation of annual flows, and the 16 variables. Rivers in the dry western districts of Victoria exhibit high variability of annual, monthly and peak flows, and low specific low flows. The converse is true for rivers in the western highlands of Victoria. Stream regionalizations are a useful tool for stream ecologists, and may be used for generating hypotheses, for detecting representative rivers and for producing baseline stream surveys.
Reproductive biology and growth of the Western School Prown, Metapenaeus dalli, in a large Western Australian Estuary
Authors: Potter IC , Baronie FM , Manning RJG , Loneragan NR
Published: November 2005

During the summer, one-year-old western school prawns (Metapenaeus dalli) congregate and spawn in reduced-salinity (< 10 g kg-1) regions of the Murray River, a tributary of the large Peel-Harvey estuarine system in Western Australia. Although some 1 + prawns are found into the following spring, few if any survive or remain in the system until the next spawning season. Growth is highly seasonal and females attain a greater carapace length than males by the end of the first year of life (18 v. 14 mm). Changes in the incidence of spermatophore deposition, gonadosomatic index (GSI) and ovarian stage during the spawning period are described. Although the timing of recruitment of O+ prawns could be related to the sharp peak in the incidence of spermatophore deposition and GSI in 1985-86, such relationships were not so clearly defined in 1987-88 when the incidence of spermatophore deposition remained above 9% for over twice the length of time.
Advection, Dispersal and Plankton patchines on the Great Barrier Reef
Authors: Parslow JS , Gabric AJ
Published: November 2005

The relative dispersal of a patch of planktonic larvae subject to advection through a complex reef matrix is considered. Attention is focused on the growth of the particle and tracer domains, and the development of patchiness. Garrett's (1983) theory for the dispersai of tracer in the open ocean is applied to the Great Barrier Reef. A simplified numerical model of flow through a reef matrix suggests that a point release of tracer will expand to a patch approximately 20 km in radius after 15 to 20 d. The predicted tracer domain is not 'streaky', but does exhibit fluctuations in concentration, with a coefficient of variation of 1 to 2 on length scales of 2 to 3 km.
Seasonal dynamics of production, and nutrient accumulation and cycling by Phragmites asutralis (Cav.) Trin. ex Stuedel in a nutrient-enriched swamp in Inland Australia. I. Whole Plants
Authors: Hocking P.J.
Published: November 2005

A study was made of the seasonal changes in dry matter production and patterns of nutrient accumulation by Phragmites australis in a nutrient-enriched swamp in inland Australia. The density of live shoots was highest (224 m-2) in October, but the peak standing crop of live shoots (9890 g m-2) occurred in early May. Peak below-ground biomass (21 058 g m-2) occurred in early August. Rhizome biomass constituted 75% of the below-ground biomass, and showed a distinct seasonal pattern. Net annual above-ground primary production (NAAP), estimated by the maximum-minimum method, was 9513 g m-2. Correction for shoot mortality and leaf shedding before, and production after, the maximum standing crop was attained increased NAAP to 12 898 g m-2. Whole plant production estimated by the maximum-minimum method was 9960 g m-2, and the corrected estimate was 14 945 g m-2. A model of dry-matter production indicated that translocation of carbohydrate from rhizomes could have provided 33% of the dry matter of shoots. About 23% of the dry matter of shoots was redistributed to below-ground organs during senescence. Concentrations of N, P, K, S, Cl and Cu declined, but concentrations of Ca, Mg, Na, Fe and Mn increased as shoots aged. Concentrations of N, P and Zn in rhizomes reached maxima in winter, and decreased in spring. Rhizomes usually contained the greatest quantity of a nutrient in the whole plant, and roots usually had less than 25% of the total plant content. There were seasonal fluctuations in the quantities of N, P, K, Zn and Cu in rhizomes. Nutrient accumulation by live shoots was underestimated by 22-55% using the maximum-minimum method. Nutrient budgets showed considerable internal cycling of N, P, K, S and Cu from rhizomes to developing shoots in spring, and from senescing shoots to rhizomes during autumn and winter.
An estimate of Bass Strait water Movement in the Western Tasman Sea during the Australian Coastal Experiment
Authors: Tomczak M , Tanner E
Published: November 2005

The presence and movement of Bass Strait Water along the continental slope of south-eastern Australia during the Australian Coastal Experiment (ACE) is estimated by evaluating the amount of salt and heat imported from Bass Strait for the five standard hydrographic ACE sections. South of Jervis Bay (35°S), the amounts decrease from September 1983 to February 1984 by a factor of two. North of Jervis Bay, the amounts depend strongly on the position of the East Australian Current and its eddies. It appears that during periods of low eddy activity Bass Strait Water can be carried northward well past Newcastle (33�S).