bluuebunny/crossref_metadata_2025 huggingface dataset:
Australian water striders of the subfamilies Trepobatinae and Rhagadotarsinae (Hemiptera : Gerridae)
Authors: Andersen Nils Møller , Weir Tom A.
Published: August 2004

The Australian fauna of water striders (Hemiptera, Gerridae) is quite diverse,comprising 12 genera and 36 species representing four of the eight extantsubfamilies currently classified in the family Gerridae. Water striders arecommon inhabitants of the surface film of both freshwater and marine habitats.The present work deals with water striders belonging to the subfamiliesTrepobatinae and Rhagadotarsinae, redescribing the seven species previouslyknown from Australia: Rheumatometra philarete Kirkaldy,Calyptobates jourama Polhemus & Polhemus,C. rubidus Polhemus & Polhemus,C. minimus Polhemus & Polhemus,Stenobates australicus Polhemus & Polhemus,Rheumatometroides carpentaria (Polhemus & Polhemus),Rhagadotarsus anomalus Polhemus & Karunaratne, anddescribing Rheumatometra dimorpha, sp. nov. fromQueensland, New South Wales and Victoria. Keys to subfamilies of Gerridaerepresented in Australia and keys to genera and species of AustralianTrepobatinae and Rhagadotarsinae are provided and the distributions of allspecies are mapped.
Retrovescus, a new genus of opisthogastric earthworm from Tasmania
Authors: Blakemore Rob
Published: August 2004

The earthworm genus Retrovescus, gen. nov. isestablished to accommodate four uncommon species with distributions restrictedto the north-west of Tasmania. The type species isRetrovescus plomleyi, sp. nov., two other species arenewly described while the fourth, R. capensis (Jamieson,1974), is redescribed and errors in the original account are corrected. A keyis provided. Characteristic traits, all apomorphies, are perichaetine setae,tubulo-racemose prostates, avesiculate meroic nephridia and opisthogastry (thedevelopment of intestinal gizzards, which in this genus are multiple in theregion of segments 20–26). Relationships and possible precursors toRetrovescus and to a sympatric genus,Nexogaster Blakemore & Kingston, 1997, which differsprincipally by its lumbricine setae and well developed typhlosole, arediscussed.
Investigations of the speciation of phosphorus in coastal and estuarine waters of the Great Barrier Reef, using iron strips and colorimetry
Authors: Chiswell R. K. , Jones G. B. , Brodie J.
Published: August 2004

A new method of determining phosphorus in sea water, using iron-impregnated
strips of filter paper, was investigated and compared with standard
colorimetric methods of phosphorus analysis. Laboratory experiments were
undertaken to determine the number of iron strips required to extract
phosphorus from sea water, the length of time a strip needed to adsorb all P
from solution, the reproducibility of the method, and whether the strips could
measure P adsorbed to different particles. Field studies were carried out with
iron strips in Cleveland Bay and the Herbert estuary, and comparisons were
made with concentrations of dissolved, particulate and organic phosphorus
determined by standard techniques. The iron-strip method was shown to work
well under laboratory conditions, but the field studies showed varying results
for the different environments tested. Generally, most of the dissolved
inorganic phosphorus present in sea water was taken up by the strips. The iron
strips also took up a proportion of other phosphorus fractions in sea water,
but the nature of this uptake appears to vary with environmental conditions.
Epizoans on a tropical freshwater crustacean assemblage
Authors: López Carlos , Ochoa Enrique , Páez Rita , Theis Solange
Published: August 2004

Prevalence and substrate specificity of epizoans on crustacean zooplankton
were examined during an annual cycle in Tulé Reservoir, a large,
shallow and polymictic waterbody in western Venezuela.
Epistylis sp., a ciliate protozoan, and
Synedra sp., a pennate diatom, were the most frequent
epibiont taxa. The prevalence of all epibionts on 1800 individual crustaceans
was only 3.3%, and the occurrence of the two epibiotic taxa together on
the same substrate zooplankter was low (3.3% of total infested
crustaceans). Cyclopoid copepods were preferred as substrate for
Epistylis sp. Neither epibiont taxon was found on
copepodids or adults of a calanoid. Both epibionts were absent in the early
rainy season but appeared in mid rainy season and showed the highest
prevalence in the early dry season. During the remainder of the dry season
prevalence was low. Epibiont prevalence was not related to presence or absence
of zooplankton taxa or water temperature. Differences from temperate epibiont
communities are discussed
Resumen. A lo largo de un ciclo anual, se estudió
la prevalencia y la especificidad al sustrato de los epibiontes de la
comunidad de crustáceos planctónicos del Embalse Tulé, un
cuerpo de agua somero y polimictico del Occidente de Venezuela.
Epistylis sp., un protozoario ciliado, y
Synedra sp., una diatomea pennada, fueron los taxones
más frecuentes. La prevalencia de ambos epibiontes en conjunto sobre
los 1.800 individuos examinados fue de 3,3% y la presencia de ambos
epibiontes en el mismo sustrato fue baja (3,3% del total de individuos
infestados). Los copépodos ciclopoideos fueron preferidos por
Epistylis como sustrato. Ningún epibionte se
observó en los copépodos calanoides. Los epibiontes aparecieron
a mediados del período de lluvias y alcanzaron su máxima
prevalencia al principio del período de sequía. La prevalencia
no se encontró relacionada ni con la presencia o ausencia de las
especies zooplanctónicas ni con la temperatura del agua. En el presente
trabajo se realizan comparaciones con las comunidades epibiónticas de
la zona templada y se discuten explicaciones a las diferencias encontradas.
Study of coastal freshwater lakes in southern New South Wales
Authors: Timms B. V.
Published: August 2004

There are few freshwater lakes associated with coastal dunes in southern New
South Wales (NSW). Lake Nargal near Narooma, Bondi Lake near Bega, and a small
lagoon near Pambula have little in common limnologically with coastal dune
lakes of northern NSW and southern Queensland. They differ in mode of origin,
are less dominated by NaCl, are less acidic, are more speciose, have few
characteristic dune-lake indicator species, and moreover contain certain
southern species. However, a re-examination of data for Lakes Windermere and
McKenzie further north at Jervis Bay suggest that these are classic
dune-contact lakes rather similar to those in northern NSW. Differences and
similarities are largely influenced by the extent and therefore the
hydrological influence of the contextural coastal sand mass and by
biogeography.
Sediments in a Portuguese coastal area — pool sizes of mobile and immobile forms of nitrogen and phosphorus
Authors: Cabeçadas G. , Brogueira M. J.
Published: August 2004

Sediment samples collected in April 1993 and July 1994 from the Tejo and Sado
coastal area have been characterized in terms of porosity,
Corg , N and P contents. Features of this region have
revealed enrichment of Tejo sediments relative to Sado sediments and
deposition of fine organic material with high concentrations of these
constituents in both Lisboa and Setúbal canyons. Lack of stratification
in the top 9 cm of sediment reflects bottom mixing, favoured by the dynamic
conditions in the zone. Loosely bound forms of P and N were measured and the
respective mobile pools estimated as far as 6 cm depth. The derived values of
159 mmol m-2 for
PO43- and 65 mmol
m-2 for NH4+
in the Tejo coastal area and 50 mmol m. -2 for
PO43- and 32 mmol
m-2 for NH4+
in the Sado coastal area suggest that a relatively large proportion of P in
the sediment, particularly in the Tejo area (20%), is available to be
mobilized into the water column and so could contribute to the enrichment in
this nutrient which is known to limit the biological productivity of most of
the area during spring.
Growth of ornate rock lobsters,Panulirus ornatus, in Torres Strait, Australia
Authors: Skewes Timothy D. , Pitcher C. Roland , Dennis Darren M.
Published: August 2004

Growth (size-at-age) of Panulirus ornatus in Torres
Strait was calculated from size–frequency data collected during annual
population surveys and from the catch of lobster fishermen. Growth varied on
both spatial (~100 km) and temporal (yearly) scales, the former probably
because of differences in water temperature and/or food availability, and
the latter probably because of density-dependent effects. Although an existing
growth curve formulated from tag–recapture data was similar to growth of
lobsters in the fast growth zones, it may overestimate the growth of lobsters
from the area where most of the tag–recapture data were collected.
Field study of compensatory changes in UV-absorbing compounds in the mucus of the solitary coral Fungia repanda (Scleractinia: Fungiidae) in relation to solar UV radiation, sea-water temperature, and other coincident physico-chemical parameters
Authors: Drollet Jacques H. , Teai Taivini , Faucon Mizaël , Martin Paul M. V.
Published: August 2004

The relationship between coral UV-absorbing compounds (mycosporine-like amino
acids, or MAAs) and solar UV radiation in the shallow coral reef environment
has been much debated. The presence of these compounds in the mucus of
Fungiidae allowed the measurement of weekly compensatory changes in the amount
and composition of these compounds together with shifts in the wavelength of
maximum absorbance (λ max. ) in the mucus of 11
specimens of Fungia repanda (Scleractinia:Fungiidae)
during 18 months of monitoring in situ in Tahiti. The
corals received full sunlight within a topless cage (specimen depth, 1 m)
located at the Arue lagoon (northern coast of Tahiti). The amount of
UV-absorbing compounds was found to be significantly and positively related to
solar UV radiation, with a lag time of one week and with a corresponding
long-wavelength shift in the maximum absorbance without lag, but was not
significantly related to sea-water temperature or to the volume of mucus
secreted. Analysis of mucus MAAs by high-performance liquid chromatography
showed that the shift in λ max. could be related to
an increase in three components: mycosporine-2-glycine, palythine and
mycosporine-glycine.
Trace-element contamination of a shallow wetland in Western Australia
Authors: Arnold T. N. , Oldham C. E.
Published: August 2004

The arsenic, chromium, iron and lead contamination of sediments in Lake
Yangebup was investigated, focussing on the potential for arsenic to be
remobilized during resuspension of contaminated sediments. Despite a distinct
source of arsenic, chromium and iron on one shore, horizontal trends in
sediment concentrations were weak. Lead concentrations were homogeneous. This
indicated a continual remobilization of these trace elements through the lake;
a likely mechanism in such a shallow lake is resuspension of bottom sediments.
An arsenic maximum was found 10 cm below the surface of the sediment in a
settled flocculant layer that predominantly comprised decaying plankton.
Remobilization of arsenic from this layer during resuspension was simulated
with elutriate tests under both oxic and anoxic conditions. Under oxic
conditions, the amount of arsenic released was correlated to the initial
concentrations of sediment arsenic, indicating that porewater was the source
of arsenic. However, in the anoxic experiments, no such correlations were
evident, suggesting that biological or chemical processes were interfering
with the redox potential and thus with the release of arsenic. Processes such
as stratification, oxygen depletion and reaeration, desorption and adsorption
in this shallow lake interact on timescales shorter than those that dominate
contaminant cycling in deeper water bodies.
Distribution of 226Ra and 210Pb in the mixed layer of the western equatorial Pacific Ocean
Authors: Towler Philip H. , Smith J. David
Published: August 2004

The residence time of particulate and dissolved 210Pb in
the upper layer of the western equatorial Pacific Ocean is examined.
Activities of dissolved 226Ra, dissolved and particulate
210Pb, and particulate 210Po were
determined to a depth of 300 m in a series of depth profiles collected along a
transect across the equator at 155˚E in November 1993. Total
210Pb in the surface water decreased from 2·7 Bq
m-3 at 10˚N to 1·8 Bq
m-3 at 10˚S. Dissolved 210Pb
generally decreased with depth but showed subsurface (100–150 m) maxima
at 10˚N and 5˚N. The nutrient concentrations at 300 m were highest
at these stations, suggesting some degree of upwelling. Calculations indicate
that the residence times of dissolved (<0·45 µm) and
particulate (>0·45 µm) 210Pb in the top
300 m were 4·6–9·6 years and 0·15–0·29
year respectively.
Morphochronological variations in the genus Posidonia
Authors: Pergent G. , Pergent-Martini C. , Cambridge M.
Published: August 2004

Morphochronological variations have been observed in five marine phanerogams
of the genus Posidonia in the two regions where they
occur (Mediterranean and Western Australia). The occurrence of these
variations, which is comparable to that of growth rings in trees (studied in
dendrochronology), has provided a basis for developing new techniques for the
investigation of characteristics of these underwater seagrass meadows (e.g.
primary production). The development of lepidochronology in the assessment of
primary production has the advantage of being rapid and allowing the
determination of the total foliar tissue production (leaf blade and leaf
sheath) including that of species for which no data were hitherto available.
Validation of skeletochronology to determine age of freshwater crocodiles (Crocodylus johnstoni)
Authors: Tucker Anton D.
Published: August 2004

Age was estimated for wild Australian freshwater crocodiles from
skeletochronology of growth marks in postoccipital osteoderms. Growth marks
were distinct and counted reliably in unstained calcified thin sections
(60–80 µm) viewed by Nomarski interference microscopy. The
periodicity of growth marks was validated directly from crocodiles of known
age (up to 19 years) and from individuals sampled sequentially in different
seasons. Growth marks comprised annuli deposited in winter and zones deposited
in summer. Errors in age estimation for small crocodiles resulted from
difficulty in assigning the growing edge as either a zone or an annulus. No
osseous remodelling was noted for immature animals. Age estimates for adult
females became unreliable as previous annuli were obscured by osseous
remodelling, presumably resulting from calcium mobilization by egg-laying
females. Old adult males continued to deposit annuli, but these were more
difficult to distinguish, being more closely spaced than in young crocodiles.
Skeletochronology permitted reliable (coefficient of variation,
3·4%) and accurate (±1 year) age estimation up to about
20 years. Osteoderm dimensions were strongly correlated with average
snout–vent length, mass and age and have acceptable potential as an
indirect means of age and size estimation for
Crocodylus johnstoni.
Accumulation of 210Po by spiny dogfish (Squalus acanthias), elephant fish (Callorhinchus milii) and red gurnard (Chelodonichthys kumu) in New Zealand shelf waters
Authors: Bellamy Peter , Hunter Keith A.
Published: August 2004

Concentrations of the natural radionuclide 210Po in the
livers of 81 individual specimens of three fish species collected from waters
of the Otago continental shelf, New Zealand, have been measured: spiny dogfish
(Squalus acanthias), 4·2 ± 1·8 Bq
kg-1 wet weight (mean ± standard deviation, n
= 48); elephant fish (Callorhinchus milii), 136
± 39 Bq kg-1 (n =
7); and red gurnard (Chelodonichthys kumu), 38 ±
13 Bq kg-1 (n = 26).
Separate measurements showed that only a negligible fraction of the
210Po was supported by decay of the
210Pb parent
(210Po/210Pb activity ratios
were 15, 134 and 5·9 respectively for the three species), indicating
that direct uptake of 210Po into the liver balances
losses from excretion and radioactive decay. The radiation dose from
210Po in the livers accounted for between 88% and
99% of the total internal absorbed dose received by the fish species.
The activity of 210Po in sea water from the study area
was 0·9–2·2 mBq L-1, yielding
concentration factors for 210Po in liver tissue in the
range 3 × 103 to 100 × 103. No significant monophasic
relationships were observed between the 210Po results
and the measured concentrations of the elements Cd, Cu, Fe, Mn, Zn and Pb,
except that Pb and 210Po were correlated
(r = 0·511) in
C. kumu.
Post-ovulatory egg viability in the snapper Pagrus auratus (Sparidae)
Authors: Hobby A. C. , Pankhurst N. W.
Published: August 2004

The role of gonadal steroids in maintaining post-ovulatory egg viability was
investigated in the snapper (Pagrus auratus), a
daily-repeat-spawning teleost. Ovulated eggs were held
in vitro in L15 medium, or in L15 medium supplemented
with gonadal steroids or gonadotrophin, to investigate any direct effects of
reproductive hormones on post-ovulatory egg viability. The viability of eggs
retained in the oviduct decreased with increasing time after ovulation, to
give fertilization of below 50% after 6 h. The viability of eggs held
in L15 medium was at least as good at that of eggs held
in vivo. Storage of eggs in L15 medium supplemented with
the reproductive hormones testosterone, 17α-hydroxyprogesterone,
17α,20β-dihydroxy-4-pregnen-3-one and human chorionic gonadotrophin
did not improve or reduce viability relative to controls, suggesting that the
hormones investigated have no direct effect on post-ovulatory egg viability.
Baseline trace metal concentrations in New South Wales coastal waters
Authors: Apte Simon C. , Batley Graeme E. , Szymczak Ronald , Rendell Paul S. , Lee Randall , Waite T. David
Published: August 2004

Concentrations of ten trace elements at five localities in New South Wales
coastal waters were measured by ultratrace sampling and analysis. Mean
concentrations of cadmium (2.4 ng L-1), copper (31 ng
L-1), nickel (180 ng L-1), lead (9
ng L-1) and zinc (<22 ng L-1)
are among the lowest reported in the Southern Hemisphere and are consistent
with recent oceanographic data for the surface waters of the Pacific Ocean.
Waters from the southernmost sampling locality (Eden) contained higher
phosphate, silicate, cadmium and nickel, but lower chromium concentrations
than waters from the other four localities, reflecting the inputs of water
from the Tasman Sea in the south compared with the dominance of waters from
the Coral Sea along the rest of the coast. Cadmium concentrations were
positively correlated with both phosphate and silicate. Chromium and lead
concentrations were also significantly correlated. It is likely that a major
source of lead is atmospheric deposition. The trace metal concentrations were
comparable to those in the surface waters of the Pacific Ocean, indicating
that fluvial inputs or processes occurring in the coastal margin were of
limited importance in determining trace metal concentrations.
Development and ecology of ocean perch larvae, Helicolenus percoides (Richardson, 1842) (Pisces:Scorpaenidae), from southern Australian waters, with notes on the larvae of other sympatric scorpaenid genera
Authors: Furlani Dianne M.
Published: August 2004

Helicolenus percoides development is described and
illustrated from a series of larvae (n = 55; body length (BL),
1.9–12.3 mm) collected from waters around Tasmania, Australia.
Broad-scale spawning occurred throughout the study area from late winter to
late summer. Helicolenus larvae are characterized by a
spongy tissue mass at the dorsal midline of the trunk. Larvae have 23–25
myomeres, a large finfold, three distinct areas of pigment (head, gut, and
ventrally on the tail), a deep body, and a coiled, compact gut. Parietal,
pterotic, preopercular, opercular, supraocular, post-temporal and
supracleithral spines form by late notochord flexion. Fin development
commences in the following sequence: pectoral, caudal, dorsal/anal
simultaneously, and pelvic, with all fin elements present by 9.0 mm BL.
H. percoides larvae are distinguished from the larvae of
three other Tasmanian scorpaenid genera (Gymnapistes,
Scorpaena and Neosebastes) by
pigmentation, spination, morphometrics and meristics.This study addressed the
question of variation within the larvae of H. percoides
species. Except for variations in ventral body pigment, no differences were
found to adequately support the separation of larvae examined into more than
one species.
Population dynamics and life history of Paratya australiensis Kemp, 1917 (Decapoda: Atyidae) in upland rainforest streams, south-eastern Queensland, Australia
Authors: Hancock Marty A. , Bunn Stuart E.
Published: August 2004

Aspects of the life history and population dynamics of Paratya australiensis
were examined in headwater streams of the Conondale Range, south-eastern
Queensland, particularly in relation to spatial and temporal variation in
temperature and flow dynamics. Breeding period and population structure at
nine sites in three subcatchments were examined during three years of monthly
sampling using a non-destructive, photographic method. Breeding was restricted
to the warmer months of late spring and summer. Peak abundances of ovigerous
females and release of larvae occurred earlier at warmer, lower-altitude sites
than at cooler, upper-altitude sites. This is consistent with the general
trend for seasonal breeding in temperate and subtropical species of atyids,
and perennial breeding in tropical species, and suggests that the summer
breeding period of P. australiensis was strongly influenced by temperature. In
subtropical, south-eastern Queensland, larvae were released just before and
during the wet season. Although populations were quite resilient, disturbance
from high-flow events also shaped the life history. Hydrology modified the
breeding period by influencing overall abundance and recruitment success and
by favouring the early release of larvae before peak flows. The reasonably
well defined seasonal cycle and synchronized development appear to result from
the combined effects of temperature and hydrology.
Occurrence of Undaria pinnatifida (Phaeophyta : Laminariales) in Port Phillip Bay, Victoria, Australia
Authors: Campbell Stuart J. , Burridge Trevor R.
Published: August 2004

In July (winter) of 1996 Undaria pinnatifida f.
typica (Harvey) Suringar was found growing on basalt
reef and rock/shell rubble in 2–4 m of water near Point Wilson, Port
Phillip Bay, Victoria. The population grew prolifically over
winter–spring with a density of up to 140 plants
m-2, with sporophytes attaining a maximum length of
approximately 800 mm. Size–frequency distributions of the population in
September 1996 suggested that the population was actively recruiting, and
examination of sporophylls indicated that plants reached reproductive maturity
at a length of approximately 400 mm. Release of zoospores was achieved in the
laboratory at temperatures between 10˚C and 15˚C, and gametophytes
and immature sporophytes developed between 10˚C and 20˚C.
Reproductive cycle and gonadal development of Macquarie perch, Macquaria australasica Cuvier (Percichthyidae), in Lake Dartmouth and tributaries of the Murray - Darling Basin, Victoria, Australia
Authors: Appleford P. , Anderson T. A. , Gooley G. J.
Published: August 2004

The gonadal development, reproductive cycle and growth of Macquarie perch,
Macquaria australasica Cuvier, in Lake Dartmouth and
selected tributaries of the Murray–Darling River Basin in south-eastern
Australia were evaluated. Gonadosomatic index (GSI) and histological analysis
were used to determine gonadal development and age and size at first maturity
in the resident Lake Dartmouth population. GSI analysis was also used to
determine age and size of Macquarie perch at first maturity in the inflowing
Mitta Mitta River and other riverine populations within the Goulburn River
catchment. Males appeared slightly smaller at first spawning than females at
all sites; both sexes were fully mature at four years of age. Differences in
size at first maturity were found between the lake and river populations; both
males and females of river populations tended to mature at a much smaller size
than the fish resident in the lake. Spawning occurred around November. Ovarian
and testicular development in this species follows a pattern similar to that
of other native Australian percichthyids. The implications for management of
recreational fisheries based on minimum size regulations is discussed in
relation to site-specific differences in growth rates and size of first
maturity of fish.
Diet of the intertidal callianassid shrimps Biffarius arenosus and Trypea australiensis (Decapoda:Thalassinidea) in Western Port (southern Australia), determined with multiple stable-isotope analyses
Authors: Boon Paul I. , Bird Fiona L. , Bunn Stuart E.
Published: August 2004

Biffarius arenosus had a mean δ13C of
–15·4 ± 0·2‰ and a mean
δ15N of 5·9 ± 0·1‰
(n = 38), and
Trypea australiensis had a mean
δ13C of –16·3 ± 0·3 and
a mean δ15N of 7·6 ± 0·1
(n = 20). The δ13C
signatures of the only mangrove species present
(Avicennia marina) and the most abundant saltmarsh plant
(Sarcocornia quinqueflora) indicated that they were not
major food sources. Seagrasses, predominantly
Heterozostera tasmanica, had mean
δ13C and δ15N values
of –11·7 ± 0·2‰ (n
= 65) and 3·9 ± 0·2‰
(n = 62), respectively. Seagrass epiphytes had
mean δ13C and δ15N
values of –17·9 ± 0·4‰ and 4·6
± 0·3‰ (n = 27),
respectively. A mixture of seagrasses and their epiphytes was the most likely
source of organic carbon for B. arenosus. Benthic
microalgae, such as diatoms, were a possible food source, but phospholipid
biomarkers indicated a meagre abundance of diatoms in the sediments, and
microscopy of shrimp guts revealed few or no diatom frustules. For
T. australiensis, food sources were less easily
distinguished than for B. arenosus, but they could
include seagrass epiphytes plus the green macroalgae
Enteromorpha spp. and/or the brown alga
Chordaria cladisiphon.
Effect of size on reproductive output of giant crabs Pseudocarcinus gigas (Lamarck): Oziidae
Authors: Gardner Caleb
Published: August 2004

Fecundity and egg size of giant crabs
(Pseudocarcinus gigas) were determined from egg masses
of 162 crabs sampled from three sites in south-eastern Australia: western
Victoria, western Tasmania and eastern Tasmania. Crabs ranged in carapace
length from 126 to 220 mm and egg number ranged from 830000 to 2500000. Egg
number and egg size increased with size of female. There appeared to be a
decline in number of eggs and size of eggs with successive broods produced
between moults. Sampling locality appeared to have little effect on
reproductive output. Regression of an allometric model of log egg number to
log crab size had a slope of 1.76 which was significantly less than 3.0. This
indicates there is not a simple volumetric relationship between the variables,
which would tend to occur if increasing fecundity with female size was a
simple function of increased body space available for ovarian development.
This pattern appeared to be a function of decreasing egg number and size with
successive broods, and the trend of increasing egg size with female size.
Observations on the diet and feeding habits of the epaulette shark, Hemiscyllium ocellatum (Bonnaterre), on Heron Island Reef, Great Barrier Reef, Australia
Authors: Heupel M. R. , Bennett M. B.
Published: August 2004

The diet and feeding habits of the epaulette shark,
Hemiscyllium ocellatum, were investigated through
stomach content analysis. Five groups of prey items were found. The index of
relative importance showed worms and crabs to be of greatest value at
51.3% and 40.1% respectively. The three minor prey groups were
shrimps (7.7%), small fishes (0.7%) and amphipods (0.3%).
Epaulette sharks tend to be crepuscular, although feeding bouts may occur at
any time. They appear to be opportunistic predators, using olfaction and
electroreception in prey capture. This species appears to be an important
benthic predator in the reef flat environment on Heron Island Reef.
Experimental manipulations of the biomass of introduced carp (Cyprinus carpio) in billabongs. I. Impacts on water-column properties
Authors: King A. J. , Robertson A. I. , Healey M. R.
Published: August 2004

Two billabongs on the floodplain of the Murrumbidgee River, Australia, were
partitioned in half with impermeable plastic barriers for four months from
summer to winter 1995. The densities of carp were manipulated to establish
high- and low-carp biomass treatments in each billabong. Final standing stocks
of carp in the high- and low-carp treatments of each billabong were 1181 and
101 kg ha-1 , and 669 and 348 kg
ha-1 , respectively. Turbidity, phytoplankton biomass
and total and dissolved phosphorus concentrations were similar in both ends of
each billabong before the establishment of the plastic barriers. Throughout
the experimental period, turbidity and phytoplankton biomass were
significantly higher in the high-carp treatment in both billabongs. However,
the two billabongs had different temporal patterns for both turbidity and
phytoplankton biomass. Concentrations of total phosphorus were usually greater
in the high-carp end of each billabong but there was no consistent pattern for
dissolved phosphorus. Carp had a significant impact on turbidity and intensity
of algal bloom but this varied with carp biomass and billabong sediment type,
and factors other than carp usually contributed to most of the variation in
measured water quality.
Nutrient enrichment of Jervis Bay, Australia, during the massive 1992 coccolithophorid bloom
Authors: Gibbs Mark T. , Marchesiello Patrick , Middleton Jason H.
Published: August 2004

A numerical simulation of the East Australian Current (EAC) has been used to
investigate the nutrification of shelf waters at Jervis Bay, south-eastern
Australia, prior to the massive coccolithophorid bloom that was first observed
on 16 December 1992. The simulation suggests that a small cold-core eddy
developed between the continental slope at Jervis Bay and the EAC jet further
offshore during 7 and 14 December 1992. This unstable cold-core eddy is likely
to have uplifted cold, nutrient-rich water onto the Jervis Bay shelf, and this
upwelling, in combination with upwelling-favourable winds, probably
transported nutrients from the deep ocean to the entrance of the bay.
Temporal patterns in macroinvertebrate drift in a northern Spanish stream
Authors: Rincón Pedro A. , Lobón-Cerviá Javier
Published: August 2004

Drift in the River Negro (Asturias, Spain) was dominated by terrestrial
invertebrates, chironomid larvae, simuliid larvae, water mites and the mayfly
Baetis rhodani. Trichopterans and
Leuctra spp. (plecopterans) occasionally exhibited
increased abundances related to events in their life cycle (hatching,
emergence). Total numbers of drifting macroinvertebrates increased after
sunset, and on some dates a second, pre-dawn peak appeared.
Baetis spp., plecopterans, adult aquatic Coleoptera and
simuliid larvae drifted mostly at night. Terrestrial invertebrates and water
mites were more abundant during the day, whereas trichopterans, chironomid
larvae and naidid oligochaetes showed no consistent diel pattern. Drift
composition changed seasonally and daily. Seasonal changes appeared to be
determined mainly by seasonal shifts in the assemblage of benthic
macroinvertebrates. The combined use of UPGMA cluster analysis and detrended
correspondence analysis showed that seasonal variation was the major factor
influencing overall drift composition, but that diel changes were only
slightly less important. The degree of diel variation also changed seasonally.
In January and March, day and night samples from a given date were quite
similar. In contrast, in May and October, diel variation was greater and the
dissimilarity between day and night samples was comparable to that between
samples from different dates.
Resumen. Los invertebrados terrestres, larvas de
quironómidos y simúlidos, ácaros acuáticos y la
efémera Baetis rhodani dominaron la deriva en el
Río Negro (Asturias, España). Tricópteros y
plecópteros (Leuctra spp.) aumentaron
puntualmente su abundancia en relación, aparentemente, con eventos en
sus ciclos de vida (eclosión, emergencia). El total de
macroinvertebrados en la deriva creció tras el ocaso y, en ocasiones,
antes del amancer. Baetis spp., los plecópteros,
coleópteros acuáticos adultos y simúlidos derivaron
principalmente durante la noche. Los invertebrados terrestres y ácaros
acuáticos lo hicieron durante el día, mientras que
tricópteros, quironómidos y naídidos no mostraron un
patrón consistente. La composición de la deriva cambió
estacional y diariamente. Los cambios estacionales parecieron relacionarse con
la variación de la comunidad de macroinvertebrados bentónicos.
El uso del análisis de agrupamiento UPGMA y del detrended
correspondence analysis identificó la estacionalidad como el principal
determinante de la composición de la deriva, pero los cambios diarios
fueron sólo ligeramente menos importantes. La magnitud de éstos
también varió estacionalmente. En enero y marzo las muestras de
día y noche de una misma fecha fueron muy parecidas. En cambio, en mayo
y octubre la diferencia fue marcada y comparable a la existente entre muestras
de fechas distintas.
Diet of the Australian sharpnose shark, Rhizoprionodon taylori, from northern Queensland
Authors: Simpfendorfer Colin A.
Published: August 2004

Stomachs from 433 specimens of Rhizoprionodon taylori
caught by gill-nets and otter trawls in Cleveland Bay, north Queensland, were
examined. At least 5.3% of specimens examined had regurgitated. Of the
remaining 410 specimens 59.0% had empty stomachs and only 19.3%
contained food items identifiable to the family level. The diet comprised
mostly small teleosts from the families Leiognathidae, Clupeidae, Teraponidae
and Engraulidae. Penaeid prawns and loliginid squid were also important in the
diet. Average weight of individual recently ingested food items was 28.5 g,
which represented 2.3% of body weight. The high diversity of potential
prey groups, high rate of regurgitation, and high proportion of empty stomachs
meant that although a large number of specimens were examined the sample size
was probably insufficient to provide a thorough analysis of the diet of
R. taylori in Cleveland Bay.
Occurrence of ultraviolet radiation-absorbing mycosporine-like amino acids in coral mucus and whole corals of French Polynesia
Authors: Teai Taivini , Drollet Jacqui H. , Bianchini Jean-Pierre , Cambon Aimé , Martin Paul M.V.
Published: August 2004

Specimens of six scleractinian species were gathered during the austral spring
(October–November) 1994 on the external slope of the barrier reef of
Arue, Tahiti, and in the lagoon of Arutua, a Tuamotu island. Mucus of each
specimen was collected and the optical density and volume excreted were
measured. After treatment, mucus was analysed for mycosporine-like amino acids
(MAAs) by high-performance liquid chromatography (HPLC). Nine UV-absorbing
compounds were present in coral mucus at concentrations between 1 and 500 ng
g-1 mucus. Palythine and mycosporine–gly were
found in all mucus studied. Mycosporine–2glycine was recovered in
71% of specimens and shinorine in 28%. Porphyra-334 and
palythinol were identified as minor MAAs. Three recently identified MAAs,
palythine–serine, mycosporine–methylamine:serine and
mycosporine–methylamine:threonine, were also found in mucus from
Pocillopora. Within a genus, there was a qualitative
similarity in MAAs determined by HPLC, irrespective of locality. Values for
optical density of the mucus showed the ability of MAAs to protect the animal
host and endosymbiotic algae from UV-solar flux and, as inferred from the
recent literature, from oxidative forms of oxygen (HO2 .
, O 2 - ,
HO.) derived from photosynthesis.
Macroinvertebrate recolonization after re-wetting of a tropical seasonally-flowing stream (Magela Creek, Northern Territory, Australia)
Authors: Dostine P. L. , Humphrey C. L. , Paltridge R. M. , Boulton A. J.
Published: August 2004

Magela Creek, a tropical stream in northern Australia, dries out for most of
its length for approximately 6 months of the year. At the end of the dry
season, the macroinvertebrate fauna of the perennial upper reaches and lowland
billabongs were sampled, as well as resting stages of the fauna in the dry
sandy streambed. With the resumption of wet-season flow, drift and benthos
were sampled from three sites along the sand tract of the creek over the
ensuing four weeks. Recolonization commenced rapidly after first flow. Most
taxa were derived from the perennial upper reaches through drift, but
contributions from an adjacent billabong and resting stages in the substratum
were important in the early stages of species establishment at the most
downstream site. The dry sandy sediments were also a significant refuge for
microcrustaceans. On the basis of this work and a review of other research, it
is concluded that the significance of dry-season refuges to recolonization of
temporary streams when flow resumes is governed by the nature of the
substratum, the severity of the dry season and the proximity of the stream to
permanent waters.
Feeding patterns of school mackerel (Scomberomorus queenslandicus) and spotted mackerel (S. munroi) in Queensland east-coast waters
Authors: Begg Gavin A. , Hopper Glen A.
Published: August 2004

Seasonal feeding and dietary overlap patterns between school mackerel
(Scomberomorus queenslandicus) and spotted mackerel
(S. munroi) in Queensland east-coast waters, Australia
(16˚S to 28˚S), were examined from June 1992 to January 1995. School
mackerel have a more diverse diet than spotted mackerel, with the diets of
both species being dominated by pilchards, anchovies and herring. Dietary
overlap between school and spotted mackerel appeared to be limited owing to
temporal and spatial separation. The seasonal availability of certain prey
items may play an important role in attracting mackerel into inshore waters
where they become accessible to the commercial and recreational fisheries.
Biology of the ornate angel shark (Squatina tergocellata) from the Great Australian Bight
Authors: Bridge Natalie F. , Mackay Duncan , Newton Gina
Published: August 2004

Ornate angel sharks were sampled from commercial catches from the Great
Australian Bight trawl fishery during the period from February 1992 to
February 1993. Size structure, reproduction and diet were studied. Both sexes
exhibited similar length–weight relationships. Morphological data
indicate that the most accurate conversion to total length (TL) would be
obtained from the distance between the granular ocelli on the trunk near the
pectoral fins. Males reached sexual maturity at a TL of 810–910 mm,
females at 1150–1250 mm. The male:female ratio was 1:3 for the
post partum population and 1:1 for embryos. Both ovaries
were functional throughout the year, but the left ovary contained more ovarian
follicles than the right. Follicle diameters ranged from 1 to 68 mm; the
largest follicle was found during autumn, before ovulation, the smallest
during spring, after ovulation. Eighteen near-term embryos from four females
were observed during January and February 1993. The number of young per female
ranged from 2 to 9. It appears that S. tergocellata has
a minimum gestation period of 6–12 months and parturition may occur
biennially. The most common stomach contents were squid
(Notodarus gouldi) and fish (mainly Monacanthidae).
Trophic function in estuaries: response of macrobenthos to natural and contaminant gradients
Authors: Gaston Gary R. , Rakocinski Chet F. , Brown Steven S. , Cleveland Carol M.
Published: August 2004

Trophic ecology of macrobenthic communities in estuaries of the northern Gulf
of Mexico was used to infer community function, determine effects of
contaminants on macrobenthos, and provide insight into community responses
following disturbance. The taxa that numerically dominated the region included
few large, deep-burrowing suspension feeders that typify estuaries elsewhere.
This pattern is indicative of disturbance, and results in dominance by trophic
groups that live near the sediment–water interface (early
benthic-community succession). Trophic structure was significantly related to
several sediment contaminants (especially metals, polynuclear aromatic
hydrocarbons, DDT), and three environmental gradients (salinity, depth, and
sediment silt–clay content). Generally, trophic diversity increased and
proportion of subsurface-deposit feeders (SSDF) decreased with salinity,
meaning that a more even distribution of trophic structure was found at
high-salinity stations.
The trophic shift toward dominance by shallow, subsurface-deposit feeders in
contaminated habitats may have dire implications for fisheries. Several
important commercial and recreational fisheries of the region depend on fish
that feed primarily at the sediment surface. Higher proportion of
subsurface-deposit feeders, coupled with low macrobenthic density in
contaminated sediments, may imply that limited energy is transferred to higher
trophic levels.
A method for sampling sandy beach amphipods that tidally migrate
Authors: Jones A. R. , Murray A. , Marsh R. E.
Published: August 2004

Some sandy beach species display tidally-related, across-beach migrations.
Such behaviour can produce false or misleading results when standard sampling
methods are used. To address this problem, a novel method was developed for
sampling migratory amphipod populations that maintain position in the swash
zone. This method provides sampling repeatability at any stage of the tide by
locating the water’s edge, defined as the median of the upper limits of
11 consecutive waves, and thus locating the migrating population. Data to test
the hypothesis of choice are then obtained via replicate core samples taken at
fixed levels above and below the water’s edge.
Use of a semi-submersible vessel to supplement satellite data in mapping the sub-tidal environment of Lonsdale Bight, Australia
Authors: McGoldrick Michael , Leach Joseph
Published: August 2004

The study was designed to identify the connection between features on the
satellite image and the sea floor in Lonsdale Bight, Victoria, Australia, and
to produce a map based on the findings. It used a semi-submersible vessel with
an observation pod that can be lowered 1 m below the sea surface; this
provides a stable platform from which spatially accurate data can be collected
in the sub-marine environment, free from atmospheric effects. The results
indicated a link between the depth and composition of the seabed and the
spectral values found in the associated satellite image. Hence, the
semi-submersible vessel is an ideal tool for seafloor imaging in shallow
waters, without the disadvantages associated with diving.
Relationship between the crustacean and molluscan assemblages of Tasmanian saltmarshes and the vegetation and soil conditions
Authors: Richardson A. M. M. , Swain R. , Wong V.
Published: August 2004

The crustacean and molluscan fauna of 65 saltmarshes around the Tasmanian
coast were sampled at three tidal levels and in three broad vegetation types,
and the salinity and organic and moisture content of the substratum were
measured concurrently. Of the 55 species of crustaceans and molluscs
collected, eight (four snails, three amphipods and a crab) were confined to
saltmarshes. Ordination of the animal data grouped the sites by the degree of
submersion, whereas ordination of the vegetation data grouped them by the
salinity of the substratum. The faunal composition could not be predicted by
the plant communities on a marsh, nor were there any strong relationships
between individual animal and plant species. Most crustaceans and molluscs
tolerated a wide range of soil conditions, but terrestrial species such as
landhoppers and woodlice were not associated with highly saline substrata.
Emergent marshes (as identified by the faunal analysis) tend to be most common
in the north-east and on Flinders Island, whereas submergent marshes are found
all round the coast. Reedy brackish marshes (as identified by the vegetation
analysis) are almost entirely confined to the west coast.
Incorporation of soft-sediment systems into a model of marine benthic community regulation
Authors: Seitz R. D.
Published: August 2004

This review (1) describes important regulating forces in
soft-sediment systems, (2) outlines existing models of
community regulation, and (3) revises a model of
community regulation to incorporate soft-sediment systems. The Menge and
Sutherland (MS) model of community regulation and its refinements were
developed for hard-bottom habitats, but can be modified for soft-sediment
systems. This ‘consumer stress model’ posits that mobile consumers
feed ineffectively in harsh environments, and that the relative importance of
physical disturbance, interspecific competition and predation varies
predictably with the magnitude of recruitment, environmental conditions,
productivity and trophic position. The MS model predicts that interspecific
competition for a resource depends directly upon the level of recruitment,
though it does not explicitly address the joint effects of recruitment and
resource availability, which are important in soft-sediment communities. The
model is here revised to incorporate hard-bottom and soft-sediment systems by
changing the recruitment axis to a ‘recruitment:resource ratio’,
whereby the effect of a given level of recruitment depends on resource
availability. The potential utility of the revised model is illustrated in a
hypothetical contrast of the effect of recruitment:resource ratios on
community regulation for a mussel-dominated assemblage in hard-bottom habitats
and an infaunal clam-dominated system in soft sediments.
Propagule predators in Kenyan mangroves and their possible effect on regeneration
Authors: Dahdouh-Guebas F. , Verneirt M. , Tack J.F. , Speybroeck D. Van , Koedam N.
Published: August 2004

Grapsid crabs can play a considerable role in the predation of mangrove
propagules and possibly are a threat to the regeneration of mangroves, whether
natural or artificial. Experiments consisting of artificial plantation of
mangrove juveniles were set up in Gazi Bay (Kenya). Grapsid crabs,
particularly Neosarmatium meinerti in the most landward
fringe and N. smithii and
Sesarma guttatum in the middle fringe of the mangrove
forest, were found to be a regeneration-limiting factor. Almost 100%
(n = 40) of the landward plantations were
cleared. There was a slight initial preference for
Rhizophora propagules lying horizontally on the mangrove
floor, which simulates the position of a stranding propagule. In Mida Creek
(Kenya) the snail Terebralia palustris was observed
predating mangrove propagules. This study shows that crabs may affect the
regeneration potential of mangroves, and snails might also be a factor in
predation. A need to actively search for ways to protect re-afforestation
plots from predators of mangrove tree juveniles is necessary.