bluuebunny/crossref_metadata_2025 huggingface dataset:
Moulting behaviour of the tiger prawns Penaeus esculentus (Haswell)
Authors: Wassenberg TJ , Hill BJ
Published: November 2005

The moulting behaviour of P. esculentus was investigated using time-lapse video equipment for several days either side of ecdysis. An ethogram was compiled using data from 1 h before to 6 h after ecdysis and the behaviour was divided into five discrete and nine continuous acts. Discrete acts occurred mainly during pre-ecdysis. Ecdysis in the laboratory and in the field was nocturnal (pooled mean time of ecdysis 2230 h) and rapid, occupying a mean time of 18.1 s. Comparison of moulting behaviour in an aquarium and in a pool of diameter 6 m indicated that confinement in a small space may produce behavioural artefacts including swimming before ecdysis and lying on the side on the bottom following ecdysis. Immediately after ecdysis the prawns flicked, swam, then walked for several metres after which they remained stationary on the surface of the substrate for a mean of 6 h before burying. In all, 70% of prawns did not feed on the night of ecdysis. P. esculentus exhibited a reduced emergence time compared with intermoult prawns on the night of the moult and on nights preceding and following ecdysis. These findings suggest that P. esculentus may have a reduced catchability in trawls on these nights.
Activation of a mangrove snail, Littorina scabra scabra (L.) (Gastropoda : Prosobranchia)
Authors: Little C , Stirling P
Published: November 2005

Cues leading to activity in L. scabra scabra in the Patonga Creek mangrove swamp, New South Wales, were investigated. Experimental stimulation with fresh water and sea water caused activity in a short time, as also did physical disturbance, but increased relative humidity had no effect. As most of the L. scabra scabra population occurred above the extreme high water of spring tides it could not have been stimulated to activity by tidal immersion. It is concluded that rain and dew are the major natural cues leading to activity.
Further observations of high-frequency current variations on the continental shelf near Sydney, New South Wales
Authors: Fang XH , Boland FM , Cresswell GR
Published: November 2005

A triangular current-meter mooring array and concurrent research vessel observations were used to observe high-frequency current variations for 9 days in April 1981 on the continental shelf off Sydney, N.S.W. Internal waves propagated onshore at 0.6 m s-1 with an energy flux of the order of 103 J m-1 s-1. One soliton-like event was recorded and it also propagated onshore at 0.6 m s-1.
Study of the spectral variation of absorption and scattering in some Australian coastal waters.
Authors: Phillips DM , Kirk JTO
Published: November 2005

The spectral variation of absorption and scattering of sea water in Jervis Bay on the east coast of Australia has been studied over the wavelength range from 400 to 700 nm. The absorption and scattering coefficients were derived from measurements of the beam attenuation coefficient and the vertical attenuation coefficient for downward irradiance using an empirical relationship based on Monte Carlo calculations. The results indicate that scattering is essentially independent of wavelength whereas absorption due to suspended and dissolved matter increases rapidly at short wavelengths. The relative contribution of absorption to total attenuation is smaller for Jervis Bay waters than for the waters of Gulf St Vincent, South Australia.
Groundwater seepage and the water balance of a closed, freshwater, coastal dune lake: Lake Windermere, Jervis Bay
Authors: Jacobson G , Schuett AW
Published: November 2005

Cyclical water-level fluctuations of up to 12 m in Lake Windermere are a response to climatic variations with a period of several years. An approximate water balance indicates that groundwater seepage is the most significant component (84%) of the outflow from the lake, whereas surface streams are the most significant component (89%) of the inflow to the lake. Groundwater flows westwards from the lake through a highly permeable Pleistocene sand aquifer.
Age and growth studies on barramundi, Lates calcarifer (Bloch), in Northern Australia
Authors: Davis TLO , Kirkwood GP
Published: November 2005

The growth of L. calcarifer was investigated in five river systems in northern Australia. Pairs of scales taken at the time of tagging and upon recapture, and seasonal data on marginal scale increments were used to verify that checks were laid down annually. Checks were formed between September and December, depending on the particular river and year. A seasonal pattern in growth was apparent from the marginal increment data and from the seasonal growth data on age 0+ fish. Growth was most rapid in the wet season (January to March). For each river system, back-calculated length at age data were obtained. Also, von Bertalanffy growth curves were fitted to both the back-calculated length at age data and length increment data from tagging. Growth curves fitted to both types of data were compared within and between rivers. No overall growth curve for L. calcarifer was obtained as there was considerable variation in growth between rivers.
Growth of two species of tiger prawn, Penaeus esculentus and P. semisulcatus, in the western Gulf of Carpentaria
Authors: Kirkwood GP , Somers IF
Published: November 2005

Growth data were obtained for the two tiger prawn species P. esculentus and P. semisulcatus from a tagging experiment carried out in February 1981 in waters adjacent to Groote Eylandt in the western Gulf of Carpentaria. A von Bertalanffy growth curve was fitted to these data and least squares estimates of the parameters L∞ and K and joint 95% confidence regions were calculated for males and females of both species. Tests on the residuals from the fitted curve were carried out to check the adequacy of the fit of the von Bertalanffy model, and differences in the parameters L∞ and K between sexes and species were examined. An alternative von Bertalanffy-type model was used to test the consistency between the estimated L∞ values and the carapace leilgths of the largest individuals observed in samples from the populations. For males of each species, the fit of the von Bertalanffy model was satisfactory, and the estimates of L∞ were consistent with the largest observed carapace lengths in catch samples. For females, however, the fit of the von Bertalanffy model was not entirely satisfactory, especially for P. semisulcatus, for which additionally the estimated L∞ was much higher than the largest carapace length in catch samples. Possible reasons for this lack of fit are discussed. Estimates of L∞ all differed significantly, with the exception of P. esculentus males and P. semisulcatus males. No significant difference was found in estimates of K for P. esculentus males and females, and only a marginally significant difference in K between P. esculentus males and females and P. semisulcatus males. Presence of a bopyrid parasite in P. semisulcatus did not affect growth.
Movements of tagged tiger prawns, Penaeus spp., in the western Gulf of Carpentaria
Authors: Somers IF , Kirkwood GP
Published: November 2005

The pattern of movements of the tiger prawns P. esculentus and P. semisulcatus in the western Gulf of Carpentaria, is described on the basis of three tagging experiments carried out in 1981. During these experiments, 13 180 individuals of P. esculentus and 6812 individuals of P. semisulcatus were tagged with Floy streamer tags and released in waters adjacent to Groote Eylandt. The first of the experiments was conducted in inshore waters north of Groote Eylandt in February. The second and third experiments were conducted in waters farther offshore north and south of Groote Eylandt in May-June. Logbook fishing-effort data were used in the interpretation of movement patterns from the geographic distribution of recaptures. From the February releases north of Groote Eylandt, both species showed movement offshore although, as a result of different directions of movement, the two species exhibited some degree of separation in the offshore fishery. The distribution of P. esculentus recaptures was generally east of the release area whereas that of P. semisulcatus was north-east. The distribution of recaptures from the June releases north of Groote Eylandt showed much less movement and separation of species than for those released inshore in February. Similarly, the recaptures from the May-June releases south of Groote Eylandt showed relatively little movement. With a few notable exceptions;these prawns exhibited only a gradual dispersal from the area of release.
Temporal changes in a demersal fish and cephalopod community of an unexploited coastal area in Northern Australia
Authors: Rainer SF
Published: November 2005

A trawl survey of the south-eastern Gulf of Carpentaria carried out at the beginning of a commercial prawn fishery in the 1960s provided data on the demersal fish of an unexploited tropical fish community. The extent of temporal variation in this community was investigated using abundance data on 359 taxa of fish and cephalopods over 13 months in 1963-1964. Seasonal changes in water temperature and salinity were large, particularly in nearshore waters. Catch rates and species richness in nearshore waters were highest during summer, and in offshore waters during autumn or winter. Shannon diversity was variable, with no clear seasonal component. Temporal changes in community composition resulted in large changes between different seasons in the structure of site groups derived by classification; temporal effects within seasons were also found. The numerically dominant species were the leatherjackets Paramonacanthus spp., the ponyfish Equulites leuciscus, the tripodfish Tripodichthys blochii, and the saury Saurida undosquamis. Squid, the ponyfish Leiognathus sp. nr blochi, the butterfly-bream Nemipterus tolu and the grunter Pomadasys maculatus were seasonally abundant. Although species were restricted in their depth range, discrete communities that maintained their identity in different seasons were apparently absent. The relative abundance of many species varied substantially wirh season and probably also over a longer period. Small changes in local abundance were often associated with movement to deeper water at times of high nearshore water temperature (summer) or of reduced nearshore salinity (autumn). Large seasonal changes occurred in the local abundance of estuarine and semidiadromous species. The community shared many species with the demersal fish community of the Gulf of Thailand. It is suggested that similar structural changes in the fish community of the Gulf of Carpentaria may occur in response to intensive fishing. Further research on the effects of demersal fishing and on the interactions of the demersal fish community with commercially important crustaceans is necessary.
Functional morphology of the mouthparts and gastric mill in Penaeus plebejus Hess (Decapoda : Penaeidea)
Authors: Suthers IM
Published: November 2005

P. plebejus is both a macrophage and a detritivore. Mouthpart structure of adult P. plebejus is similar to that of other macrophagous decapods, but the proventriculus is less calcified than in reptant decapods and the triturative surfaces of the gastric mill are small. These features have led previous authors to postulate that maceration of large food by penaeids occurs mainly at the mouthparts. In P. plebejus, the mouthparts function as in macrophagous reptant decapods, the food being torn between the mandibles and third maxillipeds and swallowed with little maceration. The proventriculus exhibits a rhythmic macerating action in which shell fragments and sand ingested with the diet play a part. The proventriculus of P. plebejus is functionally analogous to a gizzard.
Life histories of some benthic insects from the La Trobe River, Victoria
Authors: Marchant R , Graesser A , Metzeling L , Mitchell P , Norris R , Suter P
Published: November 2005

The life histories of the following species were studied over 2 years at various sites throughout the catchment of the La Trobe River: Tasmanocoenis tonnoiri and Tasmanocoenis sp. (Ephemeroptera : Caenidae), Atalophlebioides sp. and two Atalonella spp. (Ephemeroptera : Leptophlebiidae), two Baetis spp. (Ephemeroptera : Baetidae), Leptoperla primitiva and L. neboissi (Plecoptera : Gripopterygidae), Cyphon sp. (Coleoptera : Helodidae), Ecnomus sp. (Trichoptera : Ecnomidae). The life cycles of these species varied from univoltine (four taxa) to bivoltine (Leptophlebiidae, Baetidae, Ecnomus sp.) or trivoltine (T. tonnoiri). Although the species displayed various degrees of synchrony of growth, distinct changes in the size distribution of the larvae or nymphs occurred with time and thus cohorts were evident.
Meiofauna associated with mangroves in the Hunter River estuary and Fullerton Cove, south-eastern Australia
Authors: Hodda M , Nicholas WL
Published: November 2005

The meiofauna from 14 sampling sites around the Hunter River estuary is described, and the factors influencing total density and relative abundance of nematodes and copepods and some species distributions are discussed. Elevation above low tide mark influenced nematode density, and salinity influenced copepod density and relative abundance. Both nematodes and copepods were most dense near the mud surface, and algal food and the depth of the reducing layer appear to be partially responsible for major differences in the density of these two taxa at different sites. Pollution also influenced the total density of both nematodes and copepods and also the relative abundance of oligochaetes: these relationships are discussed in the light of other, contradictory, reports.
Limnological studies of waterfowl habitat in south-western New South Wales. I. Water chemistry
Authors: Briggs SV , Maher MT , Carpenter SM
Published: November 2005

Water chemistry in two impermanent wetlands in inland south-westem New South Wales was studied
as part of a larger investigation into the relationship between water level rises and waterfowl breeding
in such wetlands. Ionic dominances, nutrient levels and relationships between nutrient or ion and
wetland, season, water level and moisture regime are considered. Sodium, potassium, calcium and
chloride concentrations, conductivity and pH were inversely related to water level. Total loads of
iron, phosphate, nitrate and sulfate increased as the wetlands flooded during wetting phases. Nitrate
and phosphate levels in experimental tanks also peaked after flooding. The effect of wetland drying
and reflooding on nutrient availability is discussed.
Feeding behaviour and limb morphology of two cladocerans with small intersetular distances
Authors: Ganf GG , Shiel RJ
Published: November 2005

Length-weight relationships, feeding rates, and surface area and morphology of the third and fourth thoracic limbs of Daphnia carinata and Ceriodaphnia quadrangula s.l. were examined. Weight (W) increased between the square and cube of body length (L). W= 7.88 × 10-7 L2.23, W= 1 .7 × 10-6 L2.26 for D. carinata and C. quadrangula s.l., respectively. Both cladocerans had small (<0.3 �m) intersetular distances. Surface areas (A) of limbs 3 and 4 increased as a power function of body length: A = 5.35 × 10-2 L2.0 (D. carinata); A = 1 .22 L1.6 (C. quadrangula s.l.). Reynolds number was < 1; boundary layers surrounding the setules overlapped at beat rates of 5 and 16 cycles s-1. Filtering rates (K) for both species increased with increasing body length according to K = 1 .8 × 10-4 L2.0 (D. carinata) and K = 1.3 × 10-5 L2.2 (C. quadrangula s.1.). K also increased as a power function of limb surface area. Filtering rates on Ankistrodesmus falcatus decreased above cell concentrations of c. 104 cells ml-1. Hourly feeding rates (No. of cells per animal) increased with increasing cell concentration up to the incipient limiting concentrations and thereafter remained relatively stable. Weight-specific feeding rates for D. carinata decreased with increasing body size but for C. quadrangula s.l. remained relatively constant. D. carinata positively selected particles in the size range 4.8-7.0 �m, whereas C. quadrangula s.l. showed no particle preference within the size range 3-12�m. Both cladocerans showed differences in their feeding behaviour when offered a range of phytoplankton species but both fed most efficiently on A. falcatus. Although these cladocerans had limb morphologies that differentiated them from their Northern Hemisphere counterparts, this was not reflected in their feeding behaviour.
Tidal studies in the One Tree Island lagoon
Authors: Wilson PR
Published: November 2005

The response of the water levels in the lagoon of One Tree Island to the external tides has been studied in two series of observations in May-June 1982 and in August 1983. The tide at the eastern end of the lagoon consistently reaches maximum height 20 min after the external maximum at this point and there is evidence that the internal maximum level is 2 cm higher than the external level. The response at several points inside the lagoon is the same. Studies of the velocity profiles with height and of the mean velocity at one point on the inner edge of the reef on the leeward side show that the tide 'turns', i.e. outflow begins, regularly 45 min before the local high water. If the outflow is wind-assisted, this effect is even more pronounced. The flow across the reef is by no means uniform, however, and at points on the windward side of the reef the inflow may continue for ~2 h after high water. The water-surface gradient across the reef was monitored at one location on the leeward side. Under light to moderate wind conditions, the velocity of the flow across the reef corresponded closely to this gradient, suggesting that inertial effects are small compared with those arising from turbulent or eddy viscosity. These results are compared with theoretical models for the tidal levels within an idealized circular lagoon surrounded by an annular reef. Some of the features of the observed tides can be reproduced using a simple axisymmetric model for which the effective viscosity is of the order of 10-2-10-3 m2 s-1. However, the windward-leeward asymmetry in the flow velocities requires the inclusion of an asymmetric forcing term representing surface wind stresses on waves breaking on the windward margin of the reef. By a suitable choice of this term, it is shown that all the features of the observed tides can be qualitatively reproduced by the model.
Heavy metal concentrations in the oysters Saccostrea cuccullata and Saccostrea sp. from the Dampier Archipelago, Western Australia
Authors: Talbot V
Published: November 2005

Ranges of concentrations (mg kg-1 wet wt) of Ag (0-0.4), Cd (0-0.8), Co (not detected), Cr (0-0.8), Mn (0.4-3.2), Ni (0.2-1 .7) and Pb (0-1 .7) were determined in S. cuccullata and Saccostrea sp. (probably S. commercialis) from several locations in the Dampier Archipelago and nearby Cape Lambert. Concentrations of Cu and Zn in individual specimens of these oysters ranged from 1.4 to 555 and from 55 to 1800 mg kg-1 wet weight, respectively, reached their maximum values at localized areas adjacent to the Dampier township and iron-ore exporting terminals at Dampier and Cape Lambert, and correlated significantly with length and wet weight. Fe concentrations in individual oysters throughout the Archipelago, which is the centre of an iron-ore exporting industry, ranged from 4.2 to 1629 mg kg-1 wet weight and did not correlate significantly with oyster length or wet weight.
Genetic variation and population subdivision in Australian barramundi, Lates calcarifer (Bloch)
Authors: Shaklee JB , Salini JP
Published: November 2005

Starch gel electrophoresis of enzymes and polyacrylamide gel electrophoresis of muscle proteins were
used to study genetic variation in 589 barramundi from three widely separated regions in northern
Australia. Presumed genetic variation was observed at 16 loci (out of 46 screened). However, only
11 of these were polymorphic at the p0.99 level. The average heterozygosity in this species was 0.032.
In nearly all cases, genotypic proportions agreed closely with Hardy-Weinberg expectations. Repeated
sampling in each region revealed little or no change in allele frequencies over a period of several
months. Similarly, comparisons of allele frequencies for fish from marine and from freshwater localities
in the south-eastem Gulf of Carpentaria failed to reveal significant genetic differences between habitats.
Between-region heterogeneity Χ2 tests indicated substantial genetic differentiation at 10 of the 11I
polymorphic loci. These data indicate the existence of at least three distinct stocks or subpopulations
of barramundi in Australia.
Age of Australian bass, Macquaria novemaculeata (Perciformes : Percichthyidae), in the Sydney Basin
Authors: Harris JH
Published: November 2005

The age of M. novemaculeata from the Hawkesbury River and other streams in the Sydney Basin, New South Wales, was determined by using otoliths. Annuli were counted after simple sectioning of otoliths and intensification of the growth-check pattern by a two-stage burning technique. Age determinations were validated by the use of fish of known age; an error of + 1 year occurred in 17% of determinations. Ages of older fish (14+ to 18+ years) were not overestimated by more than 2-4 years, if at all. Progression of year-classes, and the annual nature of growth-check formation, further validated age determinations. Scale-reading seriously underestimated the age of bass. M. novemaculeata is a long-lived species. The oldest fish was 22+ years, and the mean age of the sample (n = 607) was 4.9 years. There are significant differences in longevity between the sexes; fewer males reach the older age-groups. About 10% of juvenlle fish deposited a growth-check in their otoliths during their upstream recruitment migration. The frequency of this 'migration check' was increased to 20% by capture and relocation of juveniles to isolated waters. A procedure was designed to identify migration checks in wild fish.
Community structure and zoogeographic affinities of the coastal fishes of the Dampier region of north-western Australia.
Authors: Blaber SJM , Young JW , Dunning MC
Published: November 2005

The species composition and broad trophic structure of the mangrove creek and open shore fish communities of the Dampier region in tropical north-western Australia are described. The habitats are characterized by a lack of freshwater influence, low turbidity and a tidal range in excess of 4 m. Both mangroves and open shores have a diversity of species typical of Indo-west Pacific coastal waters but the physical conditions have modified the community structure both to exclude many families that prefer areas of higher turbidity and reduced salinity, and to include others that usually occur only in clear waters. The fish faunas of the mangroves (113 species) and open shores (106 species) are compared: 54 species were common to both. The deeper waters were dominated by piscivores, which penetrated throughout the mangroves at high tide. Iliophagous species were abundant, particularly in the mangroves where the organic content of the substratum (7.8-8.2%) was not reduced markedly compared with other areas of the Indo-Pacific, despite the lack of freshwater inflow. The clear and deep water in the mangroves at high tide favour predation on juveniles by piscivorous fishes and reduce the effectiveness of such areas as nurseries. There is virtually no overlap of the fauna with that of the deeper waters (>20 m) of the North West Shelf, and the inshore region is not a significant nursery ground for any of the commercially important deeper water species.
Distribution and life histories of abundant crustaceans of four sandy beaches of south-eastern New South Wales
Authors: Dexter DM
Published: November 2005

The geographical distribution, habitat separation, reproductive periodicity, fecundity, population size structure, and other life-history features of several crustaceans dominant in four sandy beaches of south-eastern New South Wales were studied. The species examined include the cirolanid isopods Pseudolana concinna and P. towrae, the exoedicerotid amphipods Exoediceroides maculosus and Exoediceros fossor, the urohaustoriid amphipod Urohaustorius metungi, and the zobrachoid amphipod Bumeralius buchalius. Closely related species were generally separated by habitat, with the exception of U. metungi and B. buchalius, which occurred together on some beaches. In these two species, ecological separation was evident in zonation patterns, size of individuals, and reproductive seasonality.
Polypocephalus sp. (Cestoda : Lecanicephalidae) as a biological marker for banana prawns, Penaeus merguiensis de Man, in the Gulf of Carpentaria
Authors: Owens L
Published: November 2005

Parasites in banana prawns, P. merguiensis, from the Gulf of Carpentaria were surveyed. Only the lecanicephalid cestode Polypocephalus sp. seemed useful as a biological marker for banana prawns. Loads of Polypocephalus sp. were low and constant at salinities from 14 to 34. At higher salinities (38), both intensity and prevalence of infection rose markedly from 0.5 Polypocephalus sp. per prawn and 27% to 6.25 and 95%, respectively. The frequency distribution of Polypocephalus sp. was adequately described by a non-truncated form of the negative binomial distribution (n = 943, p = 35.4, k = 0.43) suggesting there were no parasite-induced mortalities. Loads of Polypocephalus sp. in prawns in the commercial catch from Albatross Bay were most similar to loads in prawns from the Mission River, which empties into Albatross Bay. Polypocephalus sp. loads in Penaeus merguiensis formed two other natural groupings, one in the south-east corner of the Gulf and one in the Cape Keerweer-Mitchell River area. There was no parasitological evidence for extensive migrations of adolescent P. merguiensis away from their nursery estuaries.
Reproductive strategy and growth of the Australian smelt, Retropinna semoni (Weber) (Pisces : Retropinnidae), and the olive perchlet, Ambassis nigripinnis (De Vis) (Pisces : Ambassidae), in Brisbane, south-eastern Queensland
Authors: Milton DA , Arthington AH
Published: November 2005

The reproductive biology and growth of R. semoni and A. nigripinnis were studied in Brisbane, south- eastern Queensland, over a 20-month period (1981-1982). R. semoni began to breed in winter at water temperatures exceeding 15�C, reflecting its salmoniform affinities and temperate distribution. A. nigripinnis, a subtropical species of Indo-Pacific origin, required a period of rising temperature before breeding began in spring at 22�C. Both species concentrated their breeding activity into the months that precede summer storms and high, variable stream discharges, which can generate fluctuating water levels, destruction of weedbeds and instability of the stream substrate. Pre-flood spawning also occurs in three other small-bodied native species in the region, and appears to have adaptive value in the seasonally unstable environments of coastal streams. Dispersal of juvenile fish may be facilitated by rising water levels during summer months following spawning. R. semoni grew faster and to larger sizes than A. nigripinnis and growth of both species was adequately described by the von Bertalanffy equation. Male and female R. semoni and male A. nigripinnis live and breed for 2 years but female A. nigripinnis survive and may breed into their third year. These patterns of survivorship and reproduction are consistent with the contention that natural mortality is higher in open-water foragers such as R. semoni than in species like A. nigripinnis, which tends to forage amongst littoral vegetation and in mid-water. Differences in the sizes of eggs and larvae of the two species are also consistent with the probability that they experience different relative exposure to predation. These and other attributes, coupled with pre-flood spawning, enable both species to achieve large populations in suitable habitats within coastal streams, in spite of their relatively low fecundities.
Particle capture by Daphnia carinata
Authors: Ganf GG , Shiel RJ
Published: November 2005

The morphology of limbs I, II and III of D. carinata was examined to ascertain whether they could act
as filters for food particles. The dimensions of limb III setules (0.29 �m), the intersetular distances
(0.23 �m), the associated Reynolds number (=10-3) and boundary layers (5-9�m) suggest that the
filtering function attributed to the limb is unlikely. Photographic data and the distribution of
Ankistrodesmus falcatus on the feeding limbs show that limb II is the limb most closely associated with
particle capture. The structural complexity of limb II suggests a functional diversity that includes
particle capture and the redirection of feeding currents produced by limbs III and IV. Analysis of
feeding rates and the size selection of algal particles shows that capture is not a simple mechanical
process.
Spatial distributions of plankton in Shark Bay, Western Australia
Authors: Kimmerer WJ , McKinnon AD , Atkinson MJ , Kessell JA
Published: November 2005

The zooplankton of Shark Bay, Western Australia, shows an unusual pattern of abundance, with an initial increase from the ocean to the central bay, and a decrease of four orders of magnitude into the hypersaline region. The daytime zooplankton abundance in Hamelin Pool, at a salinity of >60 mg 1-1, is of a similar magnitude to that of the deep sea, and 100-fold below typical surface oceanic values. Night abundances are higher, but still well below surface oceanic values. The diverse oceanic community of net phytoplankton and zooplankton is replaced at intermediate salinities by a less diverse bay community, dominated by diatoms and several small copepods. At high salinities, the phytoplankton are mostly dinoflagellates and the zooplankton are mainly demersal forms. The abundance patterns for individual species can be attributed to intolerance of high salinity, although the pattern of total abun- dance is apparently due to extreme nutrient limitation in the hypersaline waters.
Growth and sexual reproduction in the scleractinian coral Montipora digitata (Dana)
Authors: Heyward AJ , Collins JD
Published: November 2005

Colony growth rate and sexual reproduction in M. digitata were quantified. Growth rate was expressed in terms of branch linear extension, with a maximum rate of 30.5 mm year-1 for the population. Gametogenesis and spawning were recorded for the first time. M. digitata has an annual gametogenic cycle followed by a brief spawning event where gametes are shed into the water before external fertilization and embryogenesis.
Taxonomic status of the mosquitofish, Gambusia affinis (Poeciliidae), in Australia
Authors: Lloyd LN , Tomasov JF
Published: November 2005

G. affinis is the only species of the genus Gambusia positively identified from Australia. Meristic characters and gonopodium morphology of specimens from 22 localities throughout Australia were examined. Both support the identification of all specimens as the subspecies G. a. holbrooki. Previous reports indicating the presence of G. a. afinis or G. dominieensis in Australia are considered incorrect.
Mangrove species distribution in relation to tide at the seafront and up rivers
Authors: Bunt JS , Williams WT , Bunt ED
Published: November 2005

The technical problems of estimating the topographic height of a mangrove species or community are discussed. Transects normal to the seaward mangrove face were taken around the coast of Australia. They confirm that a stable margin will be approximately at mean sea level but that erosion, accretion or other disturbance may cause variation of the order of �1 m. Studies in four species-rich rivers in north Queensland show that (i) there are marked distributional differences with respect to topographic height between long and short river estuaries, these differences being attributable to different tidal patterns; and (ii) there appear to be two mangrove types: the frontal species are tolerant of inundation, poorly adapted to emersion, whereas the upstream species behave as dry-land plants tolerant of only limited inundation. The topographic height range of individual plants of a single species may be almost 4 m, so that observations on individual plants are of little value.
Uptake of phosphorus and nitrogen by Myriophyllum aquaticum (Velloza) Verd. Growing in a wastewater treatment system
Authors: Nuttall PM
Published: November 2005

The potential of the aquatic macrophyte M. aquaticum to remove nitrogen and phosphorus from secondarily treated wastewater effluent was investigated over 13 months. The flow-through wastewater treatment system consisted of three separate lagoons, the first lagoon with a floating mat of aquatic plants, the second with aquatic plants and aerated, and the third with aquatic plants under a polythene canopy and aerated. The aerated, canopy-covered lagoon was more efficient than the two other lagoons at removing influent ammonia- nitrogen (41 .I%), total nitrogen (16.7%), total phosphorus (4.2%), suspended solids (65%) and biochemical oxygen demand (18.1%). Influent phytoplankton numbers were also reduced by 98.6%. Following an initial planting density of 10 kg m-2 on a wet weight basis, the standing crop of aquatic plants in the aerated, canopy-covered lagoon had a mean daily growth rate of 6.27 g m-2 from May to October, resulting in daily accumulation rates of phosphorus and nitrogen of 0.12 g m-2 and 0.22 g m-2, respectively. Test pieces of M. aquaticum grown in separate enclosures within each lagoon had a mean daily growth rate of 7.0 g m-2 on a dry weight basis through winter in the aerated, canopy-covered lagoon and 18.0 g m-2 through summer in the exposed. aerated lagoon. Highest daily accumulation rates of the macronutrients were obtained in the exposed, aerated lagoon during spring and summer, with 0.43 g m-2 phosphorus and 1.26 g rn-2 nitrogen. Harvesting of plants resulted in an increase in ammonia-nitrogen in the lagoon effluent, caused by the removal of bacterial nitrifiers present on plant roots. Without harvesting, aufwuch accumulation on M. aquaticum and light restriction by the canopy resulted in a decrease in the phosphorus and nitrogen demand.
Revision of the Australian Cyclopidae (Copepoda : Cyclopoida). I. Acanthocyclops Kiefer, Diacyclops Kiefer and Australocyclops, gen. Nov
Authors: Morton DW
Published: November 2005

The Australian species of Acanthocyclops Kiefer, Diacyclops Kiefer and Australocyclops, gen. nov. are revised and the following species are recognized: Acanthocyclops robustus (Sars), Diacyclops bisetosus (Rehburg), D. cryonastes, sp. nov., Australocyclops australis (Sars), A. palustrium, sp. nov. and A. similis, sp. nov. All are described, figured and discussed and keys are provided for their identification.
NOAA satellite and air-borne sensing of a small-scale, coastal tidal jet
Authors: Hearn CJ , Pearce AF
Published: November 2005

Koombana Bay, on the south-west coast of Australia, contains a tidal jet that emanates from Leschenault Inlet via a man-made channel 150 m wide. The tides are of mixed diurnal-semidiurnal character. The strongest jets are induced by the diurnal tide and flow at night in summer and during daytime in winter. The duration of the discharge is about 9 h, after which the maximum length of the jet is a few kilometres. Extensive field studies together with numerical and analytical modelling have recently been completed on the jet. These allowed predictions of optimum times for viewing the jet via an air-borne thermal scanner aboard the CSIRO Fokker F27 aircraft, and a NOAA7 satellite image. The air-borne image mapped the late-summer jet, which consisted of night-cooled water from the shallow Inlet. Because the satellite pass occurs in late afternoon, the seasonality of the tide limits visibility of the jet in the imagery to late winter. The NOAA7 image shows a jet composed of warm water that has been heated during the day inside the Inlet. These observations confirm the sea data and model results and are believed to be the first use of NOAA imagery to resolve a coastal oceanographic feature of this scale.
Sedimentary provinces of the fishing grounds of the North West Shelf of Australia: Grain-size frequency analysis of surficial sediments
Authors: McLoughlin RJ , Young PC
Published: November 2005

As part of a multidisciplinary study of the continental shelf of north-west Australia, 354 sediment samples were taken to describe the distribution of sedimentary provinces contained within the region. A grain-size frequency analysis and subsequent classification have revealed six principal sediment types roughly corresponding to an east-west and inshore-offshore distribution. The study area is characterized by coarse skeletal detritus in the south-west, with a transition to a significant accretionary carbonate component in the form of oolites, pellets and infilled biogenic particles in the north-east. Superimposed on this pattern is a decrease in grain size from shallow to deeper waters, culminating in carbonate muds on the shelf slope. Carbonate content of sediments is uniformly high, ranging from 60 to 100% of the total weight of all samples. Non-carbonate material is principally clay; however, small quantities (less than 1%) of fine sand-size angular quartz are present.
A study of food chains in seagrass communities. III. Stable carbon isotope ratios
Authors: Nichols PD , Klumpp DW , Johns RB
Published: November 2005

Stable carbon isotope determinations have been used to obtain a general background to food chains being studied by a range of chemical and biological techniques. δ13C values indicate that animals (δ13CC - 11.4‰ to - 14.9‰), including two locally important commercial fish, Platycephalus laevigatus (rock flathead) and Hyporhamphus melanochir (southern sea garfish), from the Corner Inlet seagrass and non-seagrass communities are dependent to varying degrees upon seagrass (δ13C - 7.0‰ to - 9.3‰) and benthic algae for their carbon source. The largest changes in δ13C values in the food chains is at the point involving seagrasses and their direct herbivores. The latter have more negative δ13C values (H. melanochir - 12.1%o, isopods - 11.4%o). Little or no change in δ13C values is apparent at the higher trophic levels (carnivores - 13 .0‰ to - 14.9‰). Epiphytic material on the fresh leaves of the two seagrass species in the Inlet is depleted in 13C when compared with the seagrass leaves. An opposite effect is observed for epiphytic material on Posidonia australis detritus.
Prey detection by the blue-eye Pseudomugil signifer Kner (Atherinidae): analysis of field behaviour by controlled laboratory experiments
Authors: Booth DJ , Pyke GH , Lanzing WJR
Published: November 2005

Observations in a brackish creek in eastern Australia indicate that the blue-eye, P. signifer, includes various kinds of insects in its diet in the proportions encountered, provided that they are below a maximum size dictated by the mouth-gape of the fish. Encounter rates are affected by prey body size and water turbidity, but not by hunger level of the fish. Fish fed on insects at rates varying between 0.04 and 0.08 mg s-1.
Use of anaesthetic to standardize efficiency in sampling abalone populations (Genus Haliotis; Mollusca : Gastropoda)
Authors: Prince JD , Ford WB
Published: November 2005

A technique based on the treatment of rocks removed from the seafloor, with either diethyl carbonate or ethanol in seawater is described for sampling populations of abalone. The results obtained using this technique are compared with those obtained using in situ underwater sampling techniques. The new technique, which is independent of sampling experience, was more effective in sampling animals between 4 and 20 mm in length and provides a quantitative method for sampling abalone populations.
Comparative study of the life cycles of six species of Dinotoperla (Plecoptera: Gripopterygidae) in Victoria
Authors: Yule C
Published: November 2005

The life cycles of six species of Dinotoperla were studied. One of these, D. bassae, only occurred in temporary pools; three species, D. thwaitesi, D. fontana and D. brevipennis, were found in intermittently flowing creeks; and these three species as well as D. eucumbene and D. christinae inhabited cool, permanent rivers. All the species were univoltine (except for D. eucumbene, which had a nymphal life span of 11-15 months). D. bassae, D. brevipennis, D. christinae and D. eucumbene had seasonal well-synchronized life cycles, although in times of severe drought the eggs of D. bassae may remain in diapause for 18 months or more. Emergence periods of all species were relatively restricted and were completed by early summer.
Circulation dynamics in the Derwent Estuary
Authors: Thomson JD , Godfrey JS
Published: November 2005

For moderate river discharges the Derwent estuary is strongly stratified in its upstream reaches; however, salt walter is flushed completely as far downstream as Bridgewater, for river discharges greater than about 150 m3 s-1. Salinity returns to normal in this section within about 10-20 days of a rainstorm. The main mixing mechanism appears to be surface stirring by the wind; a semi-empirical formula for wind-driven entrainment velocity gives values a factor of about 1 .5 too small, but this may be due to a number of sources of observational error. Tidal mixing is detectable in the upstream Derwent, but is small compared to wind mixing in terms of induced vertical flows.
Mating and spawning in the mudcrab, Scylla serrata (Forskaål) (Decapoda: Portunidae), in Moreton Bay, Queensland
Authors: Heasman MP , Fielder DR , Shepherd RK
Published: November 2005

Mating activity in a southern Queensland population of S. serrata was at a maximum level in mid-spring and late summer-early autumn. Spawning activity, as indicated by the incidence of spent females, began early in spring and ended in early autumn while water temperatures exceeded approximately 22�C. Nevertheless, ovary condition was apparently held constant during the colder non-spawning half of the year. Ovary condition was not correlated with either ovary coloui or crab size.
Life history of Mytilocypris henricae (Chapman) (Crustacea: Ostracoda) in Lake Bathurst, New South Wales
Authors: Martens K , Deckker P , Marples TG
Published: November 2005

The life history of the halobiont ostracod M. henricae was studied over a 2.5-year period in Lake Bathurst, a slightly saline lake in New South Wales. Samples were collected monthly or bimonthly between March 1981 and May 1982 and weekly between August 1982 and June 1983. Relative abundance of all nine life stages (eight larval stages and one adult stage) in the samples was determined. Furthermore, in 10 selected monthly samples, sex-ratio, relative abundance of three female maturity stages and number of eggs in uteri of ovigerous females were monitored. Nearly all life stages were present throughout the year and M. henricae is thus a perennial form in Lake Bathurst. Relative abundance of life stages suggests that M. henricae produces three successive generations per year. The spring generation, hatched from eggs laid during winter, matures around November-December. Its larval development takes between 4 and 5 months. The summer generation matures after a larval development of 2.5 months; this short period is ascribed to more favourable temperatures. The autumn generation takes about 4 months to mature.
Artificial-substratum periphyton and water quality in the lower La Trobe River, Victoria
Authors: Chessman BC
Published: November 2005

Between February 1975 and March 1977, periphyton from artificial substrata (glass microscope slides) and water samples for physicochemical analysis were obtained from eight sites on the lowland section of the La Trobe River, which flows through agricultural, urban and industrial areas. Total organic matter on the slides, estimated as weight loss on ignition, was usually highest in summer or autumn when river flows were low. However, chlorophyll a densities generally peaked in late winter and spring when nitrate concentrations were high, except at a site upstream of major urban and industrial areas, where a summer-autumn increase occurred. Thermal discharges from major power stations had no obvious effect on chlorophyll abundance, but did appear to substantially influence diatom assemblage composition from late summer to early winter, when river temperatures were highest. Downstream of the Morwell River confluence, diatom assemblages were influenced by a sharp increase in dissolved solids concentration and probably also by the grazing activities of snails (Ferrissia petterdi and Physastra gibbosa). The diatom flora at the most downstream site showed some evidence of recovery from thermal effects.
Estimates of ecosystem metabolism in the La Trobe River, Victoria
Authors: Chaessman BC
Published: November 2005

Diel oxygen-curve techniques were used to estimate gross primary productivity (PG), community respiration and net daily metabolism (NDM) for five reaches of the La Trobe River from headwaters to lowlands. All reaches were heterotrophic throughout the study (December 1980-November 1981) with NDM ranging from - 1 to -6 g O2 m-2. PG was consistently very low at the most upstream station and highest in the middle reaches of the river, where both benthic and planktonic contributions were important. At the most downstream station benthic productivity was negligible but planktonic productivity was appreciable in spring and autumn. PG in the river may be limited in the upper reaches by lack of light (due to shading by vegetation) and low levels of nutrients, and in the lower reaches by turbidity and increased depth.
Physical property distributions and seasonal trends in Spencer Gulf, South Australia: an inverse estuary
Authors: Nunes RA , Lennon GW
Published: November 2005

Results are described from the first long-term, systematic program of oceanographic measurements in Spencer Gulf, South Australia. The gulf belongs to a subset of semi-enclosed seas that are characterized by a net fluid loss, in this case induced by excess evaporation, and a resulting circulation that is the reverse of that found in a classical estuary. In Spencer Gulf, this inverse estuary character involves the production of salinities as high as 48 at the head in late summer. The seasonal variations of temperature and salinity, from both large-scale CTD surveys and time-series observations at a fixed station, reveal the manner in which the gulf responds to seasonal influences. From such information, the gulf's dispersive capabilities are quantitatively assessed, and the implications of thermohaline processes for gulf-ocean exchange are discussed.
Life cycle of the western school prawn, Metapenaeus dalli Racek, in a Western Australian estuary
Authors: Potter IC , Penn JW , Brooker KS
Published: November 2005

The absence of marine records for M. dalli below latitude 31�S., together with data on gonadal stages and spermatophore deposition on females of this species in the Swan estuary, provide very strong indications that the western school prawn typically breeds in estuarine environments in south-western Australia. The 0 + recruits, which first appeared in samples in February, remained in the estuary during the following months and by November had reached a size suitable for exploitation. At this time they were approaching sexual maturity and were starting to move from the shallows to the deeper waters of the estuary where they remained for their second year of life. In contrast to Australian Penaeus species, M. dalli mates during the intermoult period when the shell is hard rather than immediately after moulting.