bluuebunny/crossref_metadata_2025 huggingface dataset:
Sulfate reduction in sediments colonized by cyanobacteria, Spencer Gulf, South Australia
Authors: Skyring GW , Chambers LA , Bauld J
Published: November 2005

Sulfate reduction rates in laminated intertidal sediments colonized by cyanobacterial mats were determined by a glass-rod radiometric technique. Sulfate reduction rates were highest in the layers of sediment immediately below (c. 5 mm) the cyanobacterial mat. An annual sulfate reduction rate for the intertidal sediments was estimated at 6 5 mol m-2. The individual sulfate reduction rates ranged from 2 to 104 mmol m-2 day-1, with the mean, median, mode and standard deviation being 21, 15, 2 and 21 mmol m-2 day-1, respectively; the mean of all standard errors (σx) for the sulfate reduction rates of replicate sets was 18%. The radiometrically determined sulfate reduction rates were consistent with δ34S values. There was a significant linear correlation between the reciprocal of the absolute temperature of incubation and the sulfate reduction rate. Some diurnal variation in sulfate reduction rates (day-time > night-time) was most probably attributable to the higher day-time temperatures. A Q10 range of 2.0-2.4 between 10 and 40�C was calculated for sulfate reduction in sediment in which the porewater salinity was 121 × 10-3 Multiple regression analyses showed that the daily sulfate reduction rates correlated significantly with salinity, temperature, porewater content and primary productivity. There was some covariance between the variables salinity, temperature and primary productivity. The estimated molar ratio between photosynthetically fixed carbon and reduced sulfate was 2:1. An equation relating sulfate reduction rate, primary productivity and environmental factors in marine environments may be useful in constructing mathematical descriptions of the sulfate-reducing process in marine environments.
Longevity, reproductive condition and growth of the western rock lobster, Panulirus cygnus george, reared in aquaria
Authors: Phillips BF , Joll LM , Sandland RL , Wright D
Published: November 2005

Rock lobsters have been reared in the laboratory from the puerulus stage up to 13 years of age, under conditions of a constant temperature of 25�C or ambient temperatures (mean 20�C, range 15-26�C). The natural death of a male held at ambient temperatures occurred at 6 years of age, and at 25�C natural deaths occurred at 6 years. However, two males, both 12 years of age, one held at 25�C and the other at ambient temperatures, are still alive. Natural deaths of females occurred at 7 and 12 years of age at 25�C and 7 years at ambient temperatures. After reaching maturity, females held at 25�C spawned repetitively. The female that survived to 12 years of age spawned 47 times and produced an estimated 22 × 106 eggs during her lifetime. A fresh mating was not required for the fertilization of each batch of eggs spawned. The two surviving males both showed a change in growth pattern at approximately 8 years of age. This event was correlated with a behavioural change: they attacked and usually killed all moulting females held in the same aquarium. A new method of representing growth data for rock lobsters by fitting empirical stochastic differential equation models to each of a series of growth phases is described.
Transfer of photosynthetically fixed carbon between the prokaryotic green alga Prochloron and its ascidian host
Authors: Griffiths DJ , Thinh L
Published: November 2005

In the symbiotic association between the prokaryotic green alga Prochloron and three didemnid host species (Diplosoma similis, Lissoclinum bistratum, Trididemnum cyclops), between 6 and 51 % of the total carbon fixed during exposure for 1 h to H14CO3- in the light (150 �E m-2 s-1) becomes associated with the host tissue. Dark fixation of 14CO2 in these ascidian species and in Lissoclinum punctatum never exceeds 6% of photosynthetic fixation at saturating light intensity. The corresponding values for dark fixation of 14CO2 in isolated Prochloron cells fall within the same range. There is very little excretion of photosynthate from whole colonies of the above ascidian species nor from Didemnum molle, Lissoclinum voeltzkowi and Trididemnum miniatum (usually less than 1 % of total photosynthate at saturation light intensity), suggesting an efficient transfer mechanism from Prochloron to host. Evidence from pulse-chase experiments suggests that transfer probably involves the early products of photosynthesis. The extent of transfer of photosynthate between Prochloron and T. cyclops varies with the rate of photosynthetic 14CO2 fixation into the whole colony but there is some transfer even at low light intensities, which strongly limit photosynthesis.
Fish of channelized and unchannelized sections of the Bunyip River, Victoria
Authors: Hortle KG , Lake PS
Published: November 2005

The distribution and abundance of fish at three channelized and three unchannelized sites on the Bunyip River in southern Victoria were investigated. Ten species of native fish, including the Australian grayling (Prototroctes maraena), and two species of introduced fish were collected in three sets of seasonal samples by electrofishing. The unchannelized sites and a channelized site directly above a small weir had significantly higher species richness, total fish biomass, numerical density and standing crop (P<0.05) than the other two channelized sites. Ammocoete lamprey larvae, short-finned eels, southern pigmy perch and brown trout were most abundant at the unchannelized sites, whereas the common jollytail was most abundant at the channelized sites. Total numbers and biomass of fish and species richness were all positively correlated (P<0.01) with the area of snags present, and species richness and fish biomass correlated positively (P<0.01) with the area of slack water. It appears that the absence of suitable habitat (viz, area of snags, area of slack water, length of bank fringed with vegetation) accounts for the lower abundance and lower species richness of fish after channelization. A small weir at one of the channelized sites ameliorated partly the effects of channelization.
Age and growth of Australian grayling, Prototroctes maraena Gnnther (Salmoniformes : Prototroctidae), in the Tambo River, Victoria
Authors: Berra TM , Cadwallader PL
Published: November 2005

The age and growth of Australian grayling were studied in 1203 individuals collected from the Tambo River, Victoria, between January and November 1979. Scales from 667 grayling were examined. The scale method of age determination was validated by the analysis of seasonal changes in the pattern of scale growth and by correspondence between ages inferred from length-frequency distributions and ages determined by scale readings. One annulus is formed on the scale by October. Most (88%) grayling belonged to the 1+ and 2+ age-classes; fish aged 3+ and 4+ made up 11% of the collection, and fish aged 5+ less than 1%. Size increased from January until May; growth ceased during winter and resumed in September. There was no difference in growth between the sexes. The largest grayling collected was a female of 253 mm fork length (Lf). The overall length-weight relationship was W = 2 715 × 10-6Lf3 2764. The relationship between total length (Lt) and Lf was Lt = 0.93 16 + 1.0742 Lf, and between standard length (Ls) and Lf was Ls = 0.8007 + 0.9095 Lf The overall ratio of males to females was 56 : 44.
Studies on southern Australian abalone (Genus Haliotis). IV. Growth of H. laevigata and H. ruber
Authors: Shepherd SA , Hearn WS
Published: November 2005

The growth of H. laevigata Donovan and H. ruber Leach was studied at several sites in South Australia by fitting the von Bertalanffy growth equation to growth data, supplemented by analysis of length- frequency distributions. Juvenile individuals of H. laevigata grow at an average rate of 0.9 mm per week, reaching a length of about 40 mm in 1 year at West Island; at Waterloo Bay H. laevigata can reach a length of 50 mm in the first year. After the first year, the annual growth coefficient (K) and the asymptotic length (L∞) for the two species at three sites are, respectively: H. laevigata-0.48 year-1 and 138 mm (West I.); 0.41 year-1 and 131 mm (Tipara Reef); 0.59 year-1 and 148 mm (Waterloo Bay); H, ruber-0 34 year-1 and 139 mm (West I.); 0.32 year-1 and 143 mm (Tipara Reef); 0 41 year-1 and 144 mm (Waterloo Bay). There are also seasonal differences in growth rate between species and between sites. These differences as well as differences in the annual growth rate within a species between sites are associated predominantly with differences in the food supply. There is differential growth between the sexes of H. laevigata at Waterloo Bay, where females grow 25% faster than males and reach a larger size.
Parasitism: the possible cause of the collapse of a Volvox population in Mount Bold Reservoir, South Australia
Authors: Ganf GG , Shiel RJ , Merrick CJ
Published: November 2005

A V. ?tertius population in Mt Bold Reservoir was found to be heavily parasitized by the rotifer Ascomorphella volvocicola, which may have led to the collapse of the V. ?tertius population.
Influence of the gulf stream upon the short-term evolution of a warm-core ring
Authors: Joyce TM , Schmitt RW , Stalcup MC
Published: November 2005

A large anticyclonic, Gulf Stream ring was surveyed during September 1981; two expendable bathythemographic (XBT) surveys, a conductivity-temperature-depth-oxygen (CTD-02) survey, and continuous underway measurements of velocity in the upper 100 m using an acoustic doppler velocimeter were conducted. The initial XBT survey revealed an elliptically shaped ring, over 240 km in diameter, with maximum surface velocities near 2 m s-1, situated well away from the Gulf Stream. However, the later CTD-02 and XBT surveys showed that over a 12-day period a northward meander of the Gulf Stream enveloped part of the ring. This caused a loss of water from the ring, resulting in both a decrease in ring diameter and a shoaling of the thermocline. Using the close relationship between geopotential anomaly and isotherm depths, approximately 33% of the geopotential anomaly signature of the ring is estimated to have been lost due to this event. Clearly, where such interactions with the Gulf Stream occur, they play an important role in the evolution of the warm-core rings.
Pelagic squid associationswith a warm-core eddy of the East Australian Current
Authors: Brandt SB
Published: November 2005

Cephalopods were sampled at night by midwater trawling in the upper 500 m in and near warm- core eddy F during summer. In all, 29 species (1019 specimens) were caught. Of the five dominant species, the squid Pterygioteuthis giardi and Brachioteuthis riisei were most numerous inside the eddy and Abraliopsis gilchristi and Pterygioteuthis gemmata had length-frequency distributions that were significantly larger outside than inside the eddy. A. gilchristi was also concentrated in warmer water and Pyroteuthis margaritifera was more common at 250 m than at shallower depths. Cluster analysis established a clear association of overall composition and relative abundances of cephalopod species with water temperature and location with respect to the eddy.
Mesopelagic crustacea in and around a warm-core eddy in the Tasman Sea off eastern Australia
Authors: Griffiths FB , Brandt SB
Published: November 2005

Decapod Crustacea were collected during five cruises (in August, September, and October 1979, February and May 1980) at sites inside, at the edge, and outside of warm-core eddy J. These sampling sites were considered to have come from different domains of the Tasman Sea water mass. All 146 samples in this time series were taken in the upper 500 m at night using horizontal tows with an RMT 8. A total of 21 494 individuals belonging to 41 species and five larval categories was found. Nine of the 18 abundant species were cosmopolitan species: typical of samples from outside, at the edge of, and inside eddy J. Oplophorus spinosus was typical only at the eddy edge. Four species were typical of the outside and edge domains, and another four were typical of the inside and edge domains. Species abundances outside the eddy were dominated by Sergia prehensilis, Gennadas gilchristi, and Acanthephyra quadrispinosa. The first two species, plus Systellaspis debilis, were dominant at the eddy edge. Six species (Systellaspis debilis, Sergia prehensilis, Sergia scintillans, Sergia splendens, Sergestes atlanticus, and Parapandalas cf. richardi) were dominant at various times inside the eddy. There were no significant differences in the abundance of Sergia prehensilis in the three domains. Systellaspis debilis was significantly more abundant inside and at the eddy edge than outside the eddy, and Gennadas gilchristi was significantly more abundant outside and at the eddy edge than inside the eddy. An analysis of the community changes with time showed that the outside communities remained very similar in spite of the 5°30' change in latitude of eddy J between August 1979 and May 1980. In contrast, the inside communities were quite dissimilar between months, and there was no trend in this pattern. The edge communities were very similar except in May, when a large increase in the abundance of Gennadas gilchristi was found. Comparisons of communities between domains within each month showed the outside and edge communities were very similar over the entire period. In contrast, the outside and inside communities became increasingly different in time, mainly caused by changes in the abundances of species inside the eddy. The inside and edge communities were also quite different, but no consistent pattern in their dissimilarity with time was seen. Differences in the size-frequency distributions of Sergla prehensilis and Systellaspis debilis between domains through time suggest that breeding and recruitment were occumng at different times inside and outside the eddy. There was little evidence for colonization of the eddy by Tasman Sea species. We conclude that a secondary succession has been initiated, probably in response to the different physical and biological environments present inside eddy J as compared with the surrounding Tasman Sea.
Euphausiid invasion/dispersal in gulf stream cold-core rings
Authors: Wiebe PH , Flierl GR
Published: November 2005

Invasion/dispersal patterns in the distribution and abundance of euphausiid species in four 2-8-month- old cold-core rings from the Gulf Stream suggest that several different physical exchange mechanisms are operating. The most important of these appear to be horizontal mixing in the mixed layer and exchange due to movement into or out of the trapped region at depth. A zone of minimum exchange is evident between 150 and 400 m. Changes in vertical distribution and abundance of warm-water species invading the ring environs suggest that only a few species, such as Stylocheiron carinatum, are able to penetrate and take advantage of the changing ring conditions in young- to middle-aged rings (2-8 months). Other near-surface warm-water species penetrate at slower rates regardless of whether they are vertical migrators (Euphausia brevis, E. hemigibba, E. tenera, Thysanopoda aequalis) or non-migrators (S. suhmii, S. abbreviatum). Deeper-living species such as S. afine, S. elongatum, Nematoscelis microps, and N. tenella, show minimal penetration of core waters in these four rings. Cold-water species expatriated in cold-core rings also show a varied response to ring decay, with some species disappearing rapidly-3-4 months (Thysanopoda longicaudata)-and others persisting for substantial periods-0.5-1 year (N. megalops, E. krohnii). Distribution of the latter two species indicates dispersal out beyond the ring core at the surface in the case of E. krohnii and at depths of 400-1 000 m in the case of N. megalops.
Edge enrichment in an ocean eddy
Authors: Tranter DJ , Leech GS , Airey D
Published: November 2005

In October 1981, relatively high concentrations of surface phytoplankton (chlorophyll a~1.5 �g1-1 relative to a background of ~0.4 �g 1-1) were observed in a cyclonic crescent of cool water along the south-eastern margin of a warm-core eddy in the south-westem Tasman Sea. Associated with this phytoplankton peak were relatively high concentrations of surface nitrate (~50�g I-1), low concentrations of oxygen (<90% satn), and a population of a copepod (Calanoides carinatus) often associated with upwellings. The salinity, oxygen and nitrate distributions suggest that an upwelling-downwelling circulation cell existed at the interface between (anticyclonic) eddy and (cyclonic) crescent. Biological enrichment was greater at the site of the crescent than where the margin of the eddy was comparatively straight. The hypothesis is advanced that such enrichment may be the basis for the association that exists between schools of southern bluefin tuna and sharp surface temperature fronts.
Effect of solar and surface boundry on contaminant diffusion in the ocean
Authors: Gabric AJ
Published: November 2005

The dispersion of neutrally bouyant contaminants from a point source in the ocean is investigated through new solutions to the convective-diffusion equation. Particular attention is given to a detailed specification of the convective terms in the equation. A three-dimensional, linearly sheared current is considered. An exact solution for the concentration distribution is obtained for the case of an ocean of infinite depth. Model predictions are shown to be self-consistent and reproduce the characteristics of tracer patch elongation and rotation, which have been experimentally observed. The considerably more difficult, and hitherto unsolved, case of a sheared current in shallow water is solved by using the regular perturbation method with vertical shear as the small parameter. Field observations taken in coastal waters agree qualitatively with the predicted distributions.
13C/12C ratios in marine food webs of the Torres Strait, Queensland
Authors: Fry B , Scalan RS , Parker PL
Published: November 2005

During a research cruise in 1979 to the area between New Guinea and northern Australia, 250 samples were collected for measurement of 13C/12C (δ13C) to analyse carbon flow in tropical marine food webs. Plants at the base of food webs could be divided into two groups on the basis of their mean δ13C values: benthic seagrasses (-8.8‰), macroalgae (-12.5‰) and epiphytic algae (-13.3‰) were enriched in 13C (had less-negative δ13C values) when compared to planktonic samples (-21.8‰). Animals collected offshore were enriched in 13C by up to 9.1‰ relative to planktonic samples and seemed to show an increasing 13C enrichment with increasing trophic level. Relative to these offshore specimens, animals collected in intertidal seagrass meadows were usually enriched in 13C by 2-8‰, indicating that 13C-enriched benthic plants are important food sources in grassflats. Unusual 13C- enriched values of -3 to -7‰ among benthic chitons, gastropods and holothurians at one grassbed site suggest that unsampled benthic microalgae are also important sources of food-web carbon in the Torres Strait.
Comparison of feeding mechanisms in two intertidal gammarideans, Hyale rupicola (Haswell) and Paracalliope australis (Haswell) (Crustacea : Amphipoda)
Authors: McGrouther MA
Published: November 2005

The feeding mechanisms of two rocky shore, intertidal, gammaridean amphipods are described. H. rupicola inhabits the lower intertidal zone and grazes primarily on macro-algae. P. australis inhabits rock pools of the littoral fringe. These pools are flushed with seawater only during rough seas and during periods of calm have a layer of amphipod faecal pellets covering the bottom. No macro-algae grow in these pools. P. australis is microphagous, grazing micro-algae from the rocks and from the faecal pellet layer. In addition to grazing, both species exhibit setal transfer feeding on the material cleaned from the body. P. australis also appears capable of filter feeding by an action involving only the mouthparts.
An ecological relationship between Aphanizomenon and Daphnia pulex
Authors: Ganf GG
Published: November 2005

Colonies of A. flos-aquae dominated the phytoplankton of a polymictic lake during a clear-water, potentially productive phase, coincident with and following a dense population of D. pulex. Intermittent breakdown of thermal stratification was correlated with initiation of A. flos-aquae populations. A. elenkinii occurred as single filaments and was restricted to summer periods of high turbidity and the absence or low concentrations of D. pulex. Enclosure experiments showed that D. pulex was largely responsible for the decline of the spring phytoplankton and the resulting clear-water phase. In enclosures subject to grazing, A. flos-aquae formed a substantial proportion of the phytoplankton biomass, whereas in the absence of D. pulex, A. elenkinii and other small phytoplankton dominated. The final biomass was a function of both the number of D. pulex and time. The critical density of D. pulex (without any correction for net efficiency) was 12-15 1-1, above which the rate of loss from the phytoplankton community exceeded the apparent growth. Above this critical density, A. flos-aquae formed most of the phytoplankton biomass and was apparently immune to grazing because of its large size. There was strong circumstantial evidence to suggest that A. flos-aquae was recruited from the sediments, but attempts to demonstrate this failed. Instead, Anabaena spiroides was shown to be recruited.
Qualitative and quantitative variation in the macrobenthic fauna of the Original Lake and new lake areas of Great Lake and Arthurs Lake, Tasmania
Authors: Fulton W
Published: November 2005

Faunal variation between sample sites in Great Lake and Arthurs Lake, using both qualitative and quantitative data, was analysed. Cluster analysis and principal coordinates analysis showed that the fauna of the original lake areas of both lakes is distinct from the fauna of the newly flooded areas. Closer relationships exist between the faunas of the old level of the two lakes than between the faunas of the old and new levels within either lake. The distinction is not attributable to depth but may be influenced by substrate differences. The effects of abnormal fluctuations in water level on benthic fauna are discussed. Biomass variation between the sample sites was examined in relation to component species groups. The sites at the old level were dominated by oligochaetes whereas chironomids contributed most to the sites at the new level. Consistent seasonal peaks were evident in the biomass at sites at the new level but not at sites at the old. The mean annual biomass levels (wet wt) for Great Lake (13.9 g m-2) and Arthurs Lake (35.9 g m-2) are compared with recorded values for other Australian and overseas lakes. Biomass levels of Australian lakes in general are also discussed.
Dissolved nutrients and organic particulates in water flowing over coral reefs at Lizard Island
Authors: Crossland CJ , Barnes DJ
Published: November 2005

Concentrations of dissolved nutrients and organic particulates were measured in seawater flowing across the windward and leeward reef flats of the lagoonal reef complex at Lizard Island. Measurements were made during the day, at night, and at various stages of the tide over a period of several weeks. The reef complex, as a whole, did not consume or export statistically significant amounts of inorganic nitrogen, phosphorus, silicate, organic nitrogen or organic carbon. Depletion or elevation of nutrient levels in one benthic zone appeared to be balanced by production or consumption in downstream zones.
Some effects of handling techniques on returns of tagged Australian salmon, Arripis trutta (Bloch & Schneider)
Authors: Stanley CA
Published: November 2005

Return rates of different tag types used on Australian salmon were briefly reviewed. Internal tags, especially with attached plastic streamers, were clearly superior. The effects of time held before tagging and injury (including scale removal) on return rate were investigated. There was no evidence of any mortality caused by these factors and salmon appear to be a robust species, little affected by the stress caused by tagging operations. However, when fish were held under adverse conditions for long periods, or when wounds were pronounced, behaviour changes were evident, which resulted in the non- participation of affected fish in movements from juvenile to adult areas. Such behavioural changes may be of importance in analysing tag data from other pelagic migratory species that could be more easily affected by stress.
Interspecific hybridization between carp (Cyprinus carpio L.) and golfish (Carassius auratus L.) from Victorian Waters
Authors: Hume DJ , Fletcher AR , Morison AK
Published: November 2005

Naturally occumng hybridization between carp and goldfish was investigated. These hybrids were
from Victoria and are probably derived from the Boolara strain carp; hybrids of Boolara strain carp
and goldfish have not previously been described. A description using meristic and morphometric
characters allowed identification of hybrids in the field. The characters of the hybrids were intermediate,
but generally showed more carp-like features.
Effects of temperature and food on instar development rates of Boeckella symmetrica Sars (Copepoda : Calanoida)
Authors: Woodward IO , White RWG
Published: November 2005

The effects of temperature and food availability on rates of instar development of B. symmetrica are described. Increasing temperature decreased total development time. There may be evidence of a compensatory plateau for development rates between 15 and 20�C. A reduced food supply reduced development rates of the instars. Females generally developed more slowly than males.
Model of the structure and motion of a warm-core ring
Authors: Flierl GR
Published: November 2005

A simple model consisting of a thin homogeneous lens overlying a stratified deeper layer is investigated. The model includes the ageostrophic effects of the surfacing front, the �-effect, which induces motion, and Rossby wave generation in the deep layer. Solutions can be found that are isolated, meaning all of the flow variables decrease rapidly with radius. These special solutions, which have no radiated deepwater wave, must also satisfy the constraint that the net angular momentum be zero. They are generally quite large and strong eddies. For smaller rings, there will be a radiated field in the deep layer as the eddy moves westward over the top. This field, found generally to the east of the eddy, will remove energy from the ring, causing it to spin down.
Observation from landsat of ocean circulation
Authors: Carpenter DJ , Thompson JD
Published: November 2005

Landsat data were used to observe variations in ocean colour in the south-western Tasman Sea adjacent to the Australian coast and in Bass Strait. These variations were interpreted as ocean-circulation patterns and these patterns were seen to be consistent with the known behaviour of the water masses in the area. The satellite data were displayed for interpretation as grey-scale and pseudo-colour images of individual bands of the raw data, as false-colour composites of three bands of the raw data, as thematic maps following multispectral classification, and as grey-scale and pseudo-colour images of data corrected for the effects of atmospheric radiance. These images were interpreted visually, appealing to the known characteristics of the satellite sensor and the typical spectra of upwelling ocean radiances.
Upstream migration by young pigmented freshwater eels (Anguilla australis australis Richardson) in Tasmania
Authors: Sloane RD
Published: November 2005

During late spring and summer, upstream migrations by young pigmented freshwater eels (elvers) can be seen at stream barriers in Tasmania. The elver runs at two major hydro-electric dams, Trevallyn and Meadowbank, were sampled regularly during the period 1977-1981 and migrations at a number of smaller stream barriers throughout Tasmania were also investigated. Migrating elvers were found to be short-finned eels, A. a. australis; only a single specimen of the long-finned eel, A. reinhardii Steindachner, was recorded. Elvers sampled at inland stream barriers were both larger and older than those found nearer the sea, indicating that eels migrate farther upstream for several years in succession. Eels involved in upstream migration were found to be shorter than 25 cm, having spent up to 10 years in fresh water. Day length, water temperature and river flow may all contribute to the initiation and control of elver migrations. The numbers of elvers involved in annual migrations at major hydro- electric dams in Tasmania are substantial: the largest migration occurs at Trevallyn, where between 3 × 106 and 5 × 106 elvers take part each year. These elvers represent a considerable stocking poterltial and could be used to expand the local wild-eel fishery.
Reproductive strategy and growth of the crimson-spotted rainbowfish, Melanotaenia splendida fluviatilis (Castelnau) (Pisces : Melanotaeniidae) in south-eastern Queensland
Authors: Milton DA , Arthington AH
Published: November 2005

M. s. fluvlatilis has a well-defined annual reproductive cycle in south-eastern Queensland. Spawning is confined to October, November and December, with the peak in October, before the onset of summer floods and unpredictable water levels in coastal streams. Juvenile fish grow rapidly and reach maturity in the year following hatching. Growth in both sexes conforms to the von Bertalanfi model, but males grow faster and to larger sizes than females. Differences in the reproductive strategy of M. s. fluviatilis in southern Queensland and that of the more northern subspecies, M. s. splendida, may be related to the relative predictability of flooding, and hence to the probability of egg and juvenile survival, in the two areas. M. s. fluviatilis has low fecundity but the species is, nevertheless, abundant in suitable environments.
Benthic studies of waterfowl breeding habitat in south-western New South Wales. I. The fauna
Authors: Maher M
Published: November 2005

Murrumbidgil Swamp and Lake Menimajeel are shallow waterbodies associated with the Lachlan River and are typical of waterfowl breeding habitat offered by the Murray-Darling Rivers system. Chironomid larvae dominated the benthic fauna of mud, stick and plant substrata at both sites, numerically accounting for 96% and 49% of all animals sampled from mud in Murrumbidgil Swamp and Lake Memmajeel, respectively, 91% and 96% of animals sampled from sticks, and 96% of animals sampled from plants (Lake Memmajeel only). Lurnbriculus variegatus and ceratopogonid larvae were also important in the fauna of mud. Mud supported higher densities of animals than did sticks or plants. Over the whole study, average biomass of animals from mud of Murrumbidgil Swamp was 3600 (2860 excluding shells) mg dry wt m-2 and Lake Memmajeel 3230 (2970) mg dry wt m-2, with annual differences occurring within each waterbody and associated with stages of the wetting-drying cycle.
Estimation of fecundity in barramundi, Lates calcarifer (Bloch), using an automatic particle counter
Authors: Davis TLO
Published: November 2005

The use of a particle-size analyser for determining the fecundity of barramundi, L. calcarifer, is described. Fecundity was determined on 29 fish, 480-1 350 mm total length. The relationship between fecundity (F × 106) and length (L, mm) was exponential, F = 0.3089 e0.0035L. Fecundity in large fish was variable with the highest estimate being 46 × 106 eggs in a fish of 1240 mm length.
Interspecific copulation in and co-occurrence of similar-sized freshwater centropagid copepods
Authors: Maly EJ
Published: November 2005

Laboratory experiments were performed in which males of a given centropagid calanoid copepod species were placed with females of another species. Five interspecific pairings were tested, and in four of these, males attempted copulation or copulated with the partner of a different species. Metasome lengths of copepods in all populations used for experiments were determined: males attempted copulation with females whose average length was 0.88-1.09 times the normal size of the female for that species. These results imply that co-occurrence of similar-sized calanoids may be rare because of mating behaviour, temporal or spatial differences in mating, rather than because of competition for resources. A survey of reported co-occurrences of centropagid copepods in the genera Boeckella and Calamoecia found in Australia supports this contention.
Reproduction annd development of Neosilurus ater (Perugia) and Neosilurus hyrtlii Steindachner (Teleostei : Plotosidae) in a tropical Queensland stream
Authors: Orr TM , Milward NE
Published: November 2005

The reproduction and development of two plotosid catfishes, N. ater and N. hyrtlii, were investigated in a seasonal tributary of the Ross River, northern Queensland. The fishes were observed to move upstream to spawn during monsoonal flooding. Their mating behaviour, embryology and larval development are described. The adaptive significance of a flood-spawning strategy is discussed in relation to food availability, predation, and aeration in seasonal tropical streams.
Survey of freshwater red algae (Rhodophyta) of south-eastern Australia
Authors: Entwisle TJ , Kraft GT
Published: November 2005

A survey of rivers and other freshwater habitats in south-eastern Australia has resulted in the
description and illustration of 14 species and two forms of red algae. With the exception of the two
species of Nothocladus, all the taxa appear to be widespread in warm to cool temperate regions of
the world. Three of the species [Chroodactylon ornatum (C.Ag.) Basson, Caloglossa leprieurii (Mont.)
J.Ag. and Bostrychia scorpioides (Gmel.) Montagne] occur in brackish and marine habitats, as well
as in fresh water. Two species [Hildenbrandia rivularis (Liebm.) J.Ag. and Audouinella hermannii
Roth] are members of fundamentally marine genera that have one or a few distinct freshwater
representatives. The remaining taxa belong to the genus Compsopogon (Compsopogonaceae,
Erythropeltidales) and the family Batrachospermaceae (Nemaliales), which have no marine
representatives and probably evolved in fresh water. This latter group consists of Compsopogon
coeruleus (Balb.) Montagne, Batrachosperrnum atrum (Huds.) Harvey, B. ectocarpum Sirodot, B.
Helminthoideum (Sirod.) Mori (two forms), B. keratophytum Bory, B. virgato-decaisneanum Sirodot,
Sirodotia suecica Kylin (two forms), Nothocladus nodosus Skuja and N. lindaueri Skuja. The survey
has added six new records to the Australian freshwater red algal flora. Nothocladus nodosus Skuja
and N. tasmanicus Skuja are synonymized; N. lindaueri Skuja, previously recorded only from New
Zealand, was found to be widely distributed in Victoria. Taxonomic characters in the genus
Batrachospermum from Australia, the largest and most difficult group of species encountered, are
reviewed.
Seasonal meromixis in three hypersaline lakes on Rottnest Island, Western Australia
Authors: Bunn SE , Edward DHD
Published: November 2005

Three of the six permanent hypersaline lakes on Rottnest Island become meromictic 'hot lakes' during winter and spring. An important factor contributing to this transient stratification is a surface input of fresh water from seepages around the lakes, which overlays the existing hypersaline layer. Heat penetrates to the monimolimnion of these clear-water lakes and is trapped by the insulating effect of the overlying less-saline water. The disappearance of the stratification at the onset of summer is thought to be due to reduced freshwater input and evaporation of the less-saline mixolimnion.
Occurence of the introduced cichlid Oreochromis mossambicus (Peters) in Queensland
Authors: Arthington AH , McKay RJ , Russell DJ , Milton DA
Published: November 2005

The Mozambique mouthbrooder, O. mossambicus, has established self-maintaining populations in two water-supply reservoirs in Brisbane, south-eastern Queensland, and in ornamental ponds and a man-made drainage system in Townsville, northern Queensland. It has bred in standing freshwater systems and in tidally flushed drains. An attempt to eradicate O. mossambicus from ornamental ponds in Townsville in 1980 was unsuccessful. The species has also been recorded from the Gascoyne River, Carnarvon, Western Australia.
Stratification in a small lagoon in the Great Barrier Reef
Authors: Andrews JC , Dunlap WC , Bellamy NF
Published: November 2005

Temperatures were measured in a small lagoon in the windward reef flat of Davies Reef in the central Great Barrier Reef and examined on three time scales to gain three perspectives on thermal stratification and the trapping of bottom water. Profiling for stratification and dye revealed layering where bottom water was trapped and released by the successive capping and uncapping of the lagoon by a diurnal thermocline. A 1-month monitoring array revealed a solar synchronization, with the temperature of reef-flat water exceeding temperatures of lagoon water by up to 1 5�C within 1 h of midday, and lagoon stratification lagging this by 1 h. There was also a lunar synchronization with mixing proceeding during nocturnal rising tides. Lagoon surface and bottom temperatures were also monitored for 11 months. The amplitude of the diurnal stratification showed no coherence either with the amplitude of the tide (marked spring-neap tides) or with scalar wind stress. The low frequency amplitude of the diurnal oscillation was coherent with the longshore wind vector at periods near 3 6 days and in a band approximately from 10 to 40 days. Daily stratification increased when winds were poleward and decreased when winds were equatonvard. Events of flushing were separated on average by 9 h, but the most frequently observed separation was 5 h and only 10% of separations exceeded 18 h during the 11 months.
Larval and juvenile development of the doughboy scallop, Chlamys (Chlamys) asperrimus (Lamarck) (Mollusca : Pectinidae)
Authors: Rose RA , Dix TG
Published: November 2005

Planktotrophic larvae of C. asperrimus were reared from zygotes with a mean diameter of 61.5�m. The smallest straight-hinged larval shell was 80�m long, and slightly protruding umbones were formed 6 days after fertilization. The length (L) and height (H) relationship of larval shells was described by the allometric growth curve H = 0.309 L1 203. Provincular structure of 13-day-old larval shells was simple and there were nine taxodontal teeth per valve, four at one end of the hinge line and five at the other end. Eye spots were conspicuous and common in pediveligers 160-220�m long. Metamorphosis occurred 20-22 days after fertilization at 17-18�C when larvae were 190�m or longer. Larvae settled on monofilament nylon collectors. Newly settled juveniles developed a distinctive byssal notch on the right valve but attachment by byssal threads was never permanent. The small size of eggs and early larvae and allometric growth of prodissoconch II shells are the most significant characteristics distinguishing the larval stages of C. asperrimus from other pectinids in Tasmanian waters.
Distribution, abundance, growth and food of freshwater eels (Anguilla spp.) in the Douglas River, Tasmania
Authors: Sloane RD
Published: November 2005

Population structure, growth and diet of the freshwater eels A. reinhardtii Steindachner and A. australis australis Richardson were studied in the Douglas River, eastern Tasmania. Fish population structure was assessed by electrofishing, and efficiency of capture was determined for 'eels' and 'other fish'. The other fishes encountered during quantitative sampling were the native Galaxias maculatus (Jenyns), G. truttaceus Valenciennes, Pseudaphritis urvillii (Cuvier & Valenciennes), Favonigobius tamarensis Johnston, and the introduced brown trout, Salmo trutta L. A. reinhardtii dominated fish biomass in the lower freshwater reaches; an estimate of 115 gm-2, recorded at the lowest sampling site, is the highest eel biomass recorded in a Tasmanian stream. A decline in the number and weight of A. reinhardtii with increased distance from the sea was related to avoidance of low water temperatures in winter and/or a parallel decline in abundance of suitable forage fish. Measurements of marginal growth increments in burnt eel otoliths indicated the formation of annual growth rings in both species. Age groups 0: 1 and 2 of A. reinhardtii were poorly represented; this was attributed to a residence in the estuary or deep pools of the river, rather than to failure in recruitment. Growth rate of A. a. australis was slower than that of A. reinhardtii. The diet of both eel species changed significantly with size. The diet of larger individuals of A. reinhardtii had an increased dependence on fish; fish were not recorded in the diet of A. a. australis. The diet of small (less than 20 cm) eels was similar for both species, a feature that may lead to direct competition during periods of low summer flows.
Critique of some practices in life-history studies, with special reference to harpacticoid copepods
Authors: Bergmans M
Published: November 2005

Published studies on the demography and reproductive strategies of harpacticoid copepods are examined critically. At the technical level, the popular approximation r ≈ In R0/Tc is shown to be inappropriate as an estimate of the intrinsic rate of increase of harpacticoids. It leads to a systematic underestimation, by 8-29%, for life histories typical of fast-breeding species. Various ad hoc variants of r and R0 calculations occurring in the literature are also criticized. .At the conceptual level, a more discriminating approach to life-history characteristics is necessary; this applies both to the assessment of their 'strategic' significance, and to their diagnostic power with regard to the various 'strategies'. Special attention is given to the non-equivalence of parity and voltinism. Recommendations that should promote the construction of a more rigorous cognitive framework are included.
Limnology of Lake Alexandrina, River Murray, South Australia, and the effects of nutrients and light on the phytoplankton
Authors: Geddes MC
Published: November 2005

Lake Alexandrina is a shallow, well-mixed freshwater system at the mouth of the River Murray. Median water renewal time is 109 days. The lake is characterized by high turbidity and high light extinction, with mean values of 93 NTU and 6.54 In units m-1, respectively. Background extinction is high and the algal biomass contributes little to light extinction. Changes in turbidity reflect disproportionate contributions from the Murray and its major tributary the Darling. Based on total phosphorus and total Kjeldahl nitrogen levels, the lake is chemically eutrophic-hypertrophic but the nitrogen to phosphorus ratio is low and levels of filterable and soluble reactive phosphorus and especially NO3/NO2-N are often low, suggesting that most of the nutrients are in particulate form and perhaps unavailable for plant growth. From 1975 to 1978, the ulotrichous green alga Planctonema lauterbornii generally accounted for more than 95% of algal cells. It was growing under conditions of low average irradiance in the mixed water column. Chlorophyll a varied seasonally, with peak values in late spring. The summer drop in chlorophyll a correlated with low availability of nutrients, especially NO3/NO2- N. Low light availability appeared to preclude blue-green algae during the present study although blooms were recorded in 1965-1967 and 1972-1973.
Distribution and abundance of freshwater eels (Anguilla spp.) in Tasmania
Authors: Sloane RD
Published: November 2005

The distribution of A. australis australis Richardson and A. reinhardtii Steindachner in Tasmania was determined from electrofishing surveys and commercial catch records. A. a. australis is abundant in coastal streams and extends far inland in the major drainage systems to the main lakes in Tasmania's Central Highlands. Density and biomass estimates for A. a. australis in streams, <0.01-1 .40 m-2 and 0.04-23.01 g m-2, respectively, are similar to those recorded for A. australis schmidtii Phillipps in New Zealand and for A. anguilla L. in Europe, A. reinhardtii is restricted to coastal lagoons and the lower freshwater reaches and estuaries of streams in north-eastern Tasmania including Flinders Island. Substantial populations of A. reinhardtii reside in these areas (0.05 m-2, 114.66 g m-2 in Douglas River). Analysis of commercial catch statistics indicates that the initial eel yields from standing waterbodies were high in the 1960s by world standards, although landings and catch per unit effort have subsequently declined.
Preliminary observations of migrating adult freshwater eels (Anguilla australis australis Richardson) in Tasmania
Authors: Sloane RD
Published: November 2005

The downstream migration of maturing adult short-finned eels, A. a. australis, was recorded at an eel trap on the Clyde River during the 1981-1982 season. 5.2 t of eels entered the trap from November to April with 53% of the catch taken during January. Of the 190 eels examined, only a single male specimen was found. Female A. a. australis migrated downstream at a mean length of 94.5 cm, a mean weight of 1700 g and a mean age of 22.1 years (range 18-30 years). There was a significant positive correlation between catch and water temperature, temperatures above 12�C being associated with eel migration. The peak catch occurred during January and coincided with the highest record of mean daily water temperature (20.5�C). The migration did not appear to be influenced by moon phase, and river flow was controlled.
Food of larvae of Spanish mackerels, genus Scomberomorus (Teleostei : Scombridae), in shelf waters of the Great Barrier Reef
Authors: Jenkins GP , Milward NE , Hartwick RF
Published: November 2005

Larvae of S. semifasciatus, S. queenslandicus, and S. commerson were dissected for gut-content analysis. S. semifasciatus larvae feed almost exclusively on larval fish, and S. queenslandicus and S. commerson larvae feed almost exclusively on larval fish and larvaceans. S. queenslandicus larvae exhibit a distinct ontogenetic change in diet, with larvaceans decreasing and larval fish increasing in dietary importance with growth. The maximum size of prey consumed by S. semifasciatus and S. queenslandicus increases with growth.
Effect of the Leeuwin Current upon sea surface temperatures off south-western Australia
Authors: Rochford DJ
Published: November 2005

Comparison of long-term mean monthly sea surface temperatures of coastal waters at comparable latitudes off south-eastern and south-westem Australia shows that, during the duration of the Leeuwin Current in autumn and winter, sea surface temperatures are 1-3�C higher off south-western Australia.
Surveys of the east Auckland and East Cape Currents, New Zealand
Authors: Denham RN , Bannister RW , Guthrie KM , Crook FG
Published: November 2005

Several hydrological surveys using expendable bathythermograph probes have been carried out east of the North Island, New Zealand. The presence of a south-easterly directed flow known as the East Auckland Current between 34 and 37�s. is confirmed. The geographical position of the current core varies with time, but bathymetric steering appears to result in a general anticlockwise flow around 34�S.,175�E. South of the main flow there appear to be weak and variable currents associated with the upper continental slope. North of the East Auckland Current core there appear to be either two eddies, one anticyclonic and the other cyclonic, or current meanders. At 37�s. the flow direction varies with longitude. South of 37% there is always a south-easterly flow around East Cape, giving rise to the East Cape Current. East of 180260E. at 37�s. there is a return northward flow of modified subtropical water, which can result in strong horizontal gradients of surface temperature and salinity. There is also evidence of warm-core eddies north-east of 40�S.,180�E.