bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of grazing interval on basal cover of four perennial grasses in a summer-dry environment
Authors: Virgona J. M. , Bowcher A.
Published: September 2002

The response to variation in grazing interval
over the spring–autumn period in southern New South Wales was examined
on 4 perennial grass species over 2 years. Plots of phalaris
(Phalaris aquatica L. cv. Sirolan), cocksfoot
(Dactylis glomerata L. cv. Porto), tall fescue
(Festuca arundinacea Shreb cv. Demeter) and a native
danthonia (Danthonia richardsonii cv. Taranna), were
grazed by sheep every 2, 5 or 8 weeks, either rainfed or given supplementary
irrigation. Basal cover was monitored over this period and is combined with
measurements of phenological development and herbage mass to explain
differences in persistence.
The seasons differed with respect to rainfall, 1994–95 being dry
compared to 1995–96. Over the 1994–95 season, the relative change
in basal cover [RCBC, the ratio of final (May 1995) to initial (September
1994) basal cover] of the 3 introduced perennial grasses was
significantly less than 1, which indicated a decline in basal cover over the
measurement period. In contrast, RCBC was 1.55 for danthonia. Grazing interval
treatments significantly affected RCBC in 1994–95, RCBC increasing with
grazing interval. In the 8-week grazing interval, RCBC did not significantly
differ from 1. Changes in density were also measured in 1994–95 and
followed a similar pattern to RCBC for species effects although there was no
significant effect of grazing interval.
In 1995–96, there were interactions between watering and both species
and grazing interval. The RCBC (September 1995–May 1996) was
significantly greater than 1 for cocksfoot and tall fescue under irrigated
conditions but not under rainfed conditions. The response to grazing interval
depended on water supply. The 5-week grazing interval led to the highest RCBC
under both rainfed and irrigated conditions. However, when rainfed, the 5- and
8-week treatments were not significantly different, whereas under irrigation,
the 2- and 5-week treatments did not significantly differ. For the
1995–96 season, a movement index (MI, ratio of newly colonised area to
that occupied throughout the season) was measured. There was a strong
interaction between species and watering but phalaris was the most mobile
(highest MI) of the 4 species under both rainfed and irrigated conditions.
The absence of any interaction between species and grazing interval in either
1994–95 or 1995–96 suggests that response to grazing of these
species may be similar despite differences in survival mechanisms.
Cold-storage-induced changes in chlorophyll fluorescence of kangaroo paw Bush Dawn flowers
Authors: Miranda J. H. , Joyce D. C. , Hetherington S. E. , Jones P. N.
Published: September 2002

Effects on vase life and chlorophyll fluorescence were evaluated for kangaroo
paw Bush Dawn flowers harvested from 3 growth environments and kept at 3
storage temperatures for 4 storage periods. Flowers were grown in a
glasshouse, shadehouse and in the open. Harvested flowers were stored at 0,
7.5 or 13°C for 1, 2, 3 or 4 weeks. Minimum fluorescence values
decreased progressively from 0.103 to 0.078 as storage temperatures increased
from 0 to 13°C. Relative fluorescence ratios of stored kangaroo paw
flowers were altered significantly in response to storage temperature, storage
duration and growth environment. Relative fluorescence ratios decreased
progressively from 0.778 to 0.649 with increasing storage duration from 1 to 4
weeks. Relative fluorescence values were 0.688, 0.784 and 0.711 for 0, 7.5 and
13°C storage temperatures, respectively. Minimum fluorescence did not
differ among the growth environments, but relative fluorescence was highest
for the shadehouse (0.760) and lowest for the open (0.695). Vase life was also
influenced by storage temperature, storage duration and flower source. Main
effect vase lives of flowers were 6.6, 7.2 and 3.4 days for 0, 7.5 and
13°C storage temperatures, respectively. Shorter vase life after
storage at 0 than at 7.5°C indicates that Bush Dawn is chilling
sensitive. Post-storage longevity of flowers from the shadehouse (6.5 days)
and glasshouse (6.3 days) was greater than from the open (4.2 days). Relative
fluorescence values, which decreased in a linear manner for all storage
temperatures as storage duration increased, were significantly correlated with
the vase life.
A survey of farms on the Central, Southern and Monaro Tablelands of New South Wales: management practices, farmer knowledge of native grasses, and extent of native grass areas
Authors: Garden D. L. , Dowling P. M. , Eddy D. A. , Nicol H. I.
Published: September 2002

Results are presented of a survey of pastoral properties on the Central,
Southern and Monaro Tablelands of New South Wales carried out during
1991—92. Landholders were interviewed to obtain information on
property size, enterprise types, grazing management, tree clearing, fertiliser
history and carrying capacity. In addition, familiarity with native grass
species, and knowledge of their value were determined. The main grazing
enterprises were wool and beef. The most common form of livestock management
was continuous grazing. Most properties had been extensively cleared of trees
(average cleared area 80%), and there had been a significant amount of
disturbance of the original pastures. This varied from 40% of total
property area for the Central and Monaro Tablelands to 60% for the
Southern Tablelands. The main form of disturbance was cultivation for pasture
sowing or fodder cropping. Landholders had used 80% more fertiliser on
disturbed areas than on undisturbed areas, with most fertiliser applied on the
Southern Tablelands and least on the Monaro Tablelands. The average carrying
capacities of undisturbed and disturbed pastures over the tablelands were 4.3
and 7.7 dry sheep equivalents per hectare, respectively. While most
landholders were satisfied with the performance of their sown pastures, there
was a lack of knowledge of the contribution of native perennial grasses to
pasture production. Using survey data, it was estimated that pastures with
native grasses as the major components covered a minimum of 1.38 million
hectares or 40% of the surveyed area. With such a large contribution to
production, there is a need to assist landholders to identify native perennial
grasses so that their potential value can be more fully realised.
Distribution, abundance and symbiotic effectiveness of Rhizobium leguminosarum bv. trifolii from alkaline pasture soils in South Australia
Authors: Denton M. D. , Coventry D. R. , Bellotti W. D. , Howieson J. G.
Published: September 2002

The current dissatisfaction with low
productivity of annual medic (Medicago spp.) pastures
has highlighted the need to seek alternative legumes to provide efficient
N2 fixation in low rainfall, alkaline soil environments
of southern Australia. Clover species adapted to these environments will have
limited N2 fixation if effective rhizobia are not
present in sufficient quantities. A survey of 61 sites was conducted across
South Australia to determine the size, distribution and effectiveness of
Rhizobium leguminosarum bv.
trifolii (clover rhizobia) populations resident in these
low rainfall, alkaline soil environments. Clover rhizobia were detected at 56
of the sites, with a median density of 230–920 rhizobia/g soil. Most
rhizobial populations were poor in their capacity to fix nitrogen. Rhizobial
populations from fields provided 11–89% and 10–85%
of the shoot biomass of commercial reference strains when inoculated onto host
legumes T. purpureum (purple clover) and
T. resupinatum (persian clover), respectively. Rhizobial
population size was correlated negatively to pH and the percentage of
CaCO3 in the soil, and was significantly increased in
the rhizospheres of naturalised clover, found at 17 sites. Management options
for rhizobial populations to improve legume diversity and productivity are
discussed in terms of rhizobial population dynamics and likely soil
constraints to successful rhizobial colonisation.
PRO Plus: a whole-farm fodder budgeting decision support system
Authors: McPhee M. J. , Bell A. K. , Graham P. , Griffith G. R. , Meaker G. P.
Published: September 2002

This paper describes PRO Plus, a whole-farm fodder budgeting decision support
system for beef, sheep meat and wool producers. The program predicts the
pasture mass available at the end of each month for individual paddocks based
on pasture growth rates, number of stock, intake and the grazing plan where
producers allocate mobs weekly to paddocks. Two case studies are presented
that identify how the program can be used individually or in conjunction with
other programs to make management decisions. PRO Plus is an integral component
of the PROGRAZE Plus course and assists producers to improve the financial
viability and sustainability of their farms through better pasture and grazing
management.
Soil water dynamics and growth of perennial pasture species for dryland salinity control
Authors: Lolicato S. J.
Published: September 2002

Fortnightly soil water content measurements to
a depth of 2.1 m under 4 cocksfoot cultivars, 2 phalaris cultivars, 2 lucerne
cultivars and 1 Lotus corniculatus cultivar were used to
compare soil profile drying and to define seasonal patterns of plant water use
of the species over a 3-year period, on a duplex soil. Cultivars were also
selected, within species groups, for varying seasonal growth patterns to
assess this influence on soil water dynamics and growth. Over the 3-year
period, treatments with the highest and lowest measures of profile soil water
content were used to derive and compare values of maximum plant extractable
water. Plots were maintained for a further 3 years, after which soil water
content measurements in autumn were used to assess long-term effects of the
treatments. The effect of seasonal growth patterns within a species was
negligible; however, there were significant differences between species.
Twenty-one months after pasture establishment, lucerne alone had a drying
effect at 2.0 m depth and subsequently it consistently showed profiles with
the lowest soil water content. Maximum plant extractable water was greatest
for lucerne (230 mm), followed by phalaris (210 mm),
Lotus corniculatus (200 mm) and cocksfoot (170 mm).
Profiles with the lowest soil water content were associated with greater
herbage growth and greater depths of water extraction. The soil water deficits
developed by the treatments in autumn of the fourth year were similar to those
measured in autumn of the seventh year, implying that a species-dependant
equilibrium had been reached. Long-term rainfall data is used to calculate the
probabilities of recharge occurring when rainfall exceeds maximum potential
deficits for the different pasture species.
Response of lentil to Rhizobium leguminosarum bv. viciae strains at different levels of nitrogen and phosphorus
Authors: Shah N. H. , Hafeez F. Y. , Arshad M. , Malik K. A.
Published: September 2002

Response of lentil
(Lens culinaris Medik) to inoculation with 3 local and 1
exotic Rhizobium leguminosarum bv.
viciae (lentil rhizobia) strains at different levels of
nitrogen and phosphorus (00:00, 20:20, 20:40, 20:60, 20:80, 40:20, 40:40,
40:60 and 40:80 kg/ha as N and
P2O5, respectively) was studied. A
field experiment was conducted on a soil deficient in nitrogen and available
phosphorus that had a very low indigenous population of lentil rhizobia.
Percentage strain recovery (nodule occupancy) revealed that the inoculant
strains were highly competitive and occupied 71–95% of the
nodules. Inoculation had significant benefits for nodulation, biomass, grain
yield, nitrogen and phosphorus uptake at all levels of nitrogen and
phosphorus. Inoculation with the local strain Lc26 increased yield by 393
kg/ha compared with the uninoculated control. Maximum biomass, and
nitrogen and phosphorus uptake were observed where nitrogen and phosphorus
were applied at the rates of 40 and 60–80 kg/ha, respectively. The
40:80 kg nitrogen and phosphorus per hectare combination gave the maximum
nodule number, nodule dry weight and grain yield (904 kg/ha) with a net
return of US$189 as compared to the unfertilised control and there was
an income of US$7 for each dollar invested on fertiliser.
Value orientations: impact and implications in the extension of complex farming systems
Authors: Frost F. M.
Published: September 2002

Many agricultural extension programs are based on principles of participation,
adult learning and action learning. Underlying reasons for adopting a
participation approach include: the increasing complexity of agricultural and
environmental problems; the uncertainty associated with recommendations; and a
need for local learning communities. Resource management issues such as
salinity and industry problems such as those faced by the wool industry, are
forcing landholders to review their current farm practices and consider
fundamental shifts in the way agriculture is conducted and indeed how it is
considered within this changing landscape. In addressing these issues, it is
important that those working with farmers understand the values and goals they
are bringing to the planning table since these important human qualities
underpin most decisions made and actions taken. This study into value
orientations of farmers was undertaken in the wheatbelt of Western Australia.
One hundred and forty one farmers, working in landcare catchment groups, were
surveyed. The results of this study show a shift in value orientations over
the last 19 years and leaving a legacy is significantly more important for
farmers in the 1990s than in the 1970s. The results also show that these
longer-term ideals co-exist with a focus on short-term security and
investment. The implications of these results are important for those working
with catchment and industry groups, particularly when planning for future
management of the landscape and farming system. It is particularly relevant to
those endeavouring to bring about fundamental shifts in the way we think about
farming systems and their integration into the local landscape.
Evaluating participatory extension programs: challenges and problems
Authors: Murray P.
Published: September 2002

Extension in Australia, in common with other parts of the world, is
increasingly including participatory and process oriented approaches. At the
same time there is an increasing requirement for accountability by government
and other funding agencies. The credibility and acceptance of emergent
participatory extension approaches to funding bodies can be improved by
appropriate evaluation. Models for evaluation of extension have developed that
are well suited to ‘transfer of technology’; however, these
outcome-oriented evaluations are not appropriate for participatory extension
approaches. Outcome focused evaluation, particularly where the focus is on
predetermined, externally imposed criteria can be stifling to genuinely
participatory extension approaches. While ‘Participatory Monitoring and
Evaluation’ offers an alternative approach, the differentials between
stakeholders, which are essentially differences in power, mean that this
approach will not provide a complete answer. Models of evaluation which meet
the requirements of funding agencies and other stakeholders need to be further
developed.
From pushing production inputs to empowering the community: a case study in the transformation of an extension agency
Authors: Macadam R. D.
Published: September 2002

The Oil Palm Industry Corporation of Papua New Guinea is transforming itself
under the leadership of a Chief Executive Officer appointed in February 1996.
During 1997, a team from the University of Western Sydney, Hawkesbury designed
and initiated an Industry Learning and Leadership Development Program for
OPIC. It began in October 1997 and finished in June 1999.
The hypothesis is presented that the process, which the program is a part of,
is enabling a transformation that constitutes a fundamental paradigm shift,
from a production input and technology transfer model of extension to a
systemic, community-development oriented one.
The case for the hypothesis is pursued through an account of the experience of
the program, and critical reflection on it. The outcomes of this are related
to the challenge presented by a paradigm shift in extension. Praxis and
effective leadership of it are put forward as an appropriate response. This is
characterised by (i) widespread dissatisfaction with the pre-existing
situation; (ii) conceptualisation of an alternative based on shared values,
(iii) facilitation of theory-informed practice in the local context, and
critical reflection on it, (iv) the internal capacity of the system to
translate opportunities for reform into protocols and procedures, (v) the
imprimatur of the ‘owners’ of the system, and (vi) access to
needed resources.
A sampling strategy to assess banana crops for damage by Radopholus similis and Pratylenchus goodeyi
Authors: Stanton J. M. , Pattison A. B. , Kopittke R. A.
Published: September 2002

The economic threshold of burrowing (Radopholus similis)
and lesion nematode (Pratylenchus goodeyi) on banana may
be used to determine whether it is economic to apply nematicide. However, to
use such a threshold, a sampling strategy is essential to determine the
severity of root damage caused by the nematode. Ten banana crops in
south-eastern Queensland and northern New South Wales and 10 in northern
Queensland were sampled several times over several years to determine the
disease index (percentage cortical root damage caused by
R. similis and P. goodeyi) and
nematode populations in roots. The negative binomial distribution and
Taylor’s power law analysis were used to determine the relationship
between the mean and variance of the disease index and nematode populations.
Taylor’s power law gave the better fit, and was therefore used to
determine fixed-precision stop lines for sequential sampling for precision at
20–30% for disease index and 20–40% for nematode
populations. Twenty samples per crop were sufficient to achieve 25%
precision when assessing nematode infestations using disease index but only
40% precision when using nematode populations.
The pastoral significance, adaptive characteristics, and grazing value of white clover (Trifolium repens L.) in dryland environments in Australia: a review
Authors: Lane L. A. , Ayres J. F. , Lovett J. V.
Published: September 2002

The importance of white clover as a pasture legume of international
significance has led to major investment in research on ecophysiology,
germplasm conservation, and white clover improvement. Despite the agronomic
merit and economic significance of white clover, Australia lacks white clover
cultivars that possess adaptive characteristics for persistence in mixed
swards under sheep and cattle grazing. The major problem with contemporary
white clover cultivars is that clover biomass fluctuates widely from year to
year. This lack of reliability, particularly in dryland environments, is
largely due to poor survival during summer moisture stress that is common to
much of the Australian white clover zone. Factors such as edaphic constraints,
intolerance of grass competition and close grazing, and lack of winter growth
in cold environments also influence the contribution of white clover to
pasture performance. This paper considers the mechanisms of regeneration,
adaptive characteristics, and significance of white clover for animal
production, and reflects on breeding objectives for white clover improvement.
Nitrogen fixation by lablab (Lablab purpureus) and lucerne (Medicago sativa) rotation crops in an irrigated cotton farming system
Authors: McDonald L. M. , Wright P. , MacLeod D. A.
Published: September 2002

Cotton producers in Australia are interested in including legume green manure
crops in their farming systems. Lablab and lucerne are 2 crops that have been
considered for this role. The object of this study was to determine their
biomass production, nitrogen fixation, water use and water-use efficiency
within a 1-year out-of-cotton rotation. Both species were grown under full
irrigation, and partial irrigation, where periods of moisture stress occurred.
During the period of the rotation, lablab produced more biomass and fixed more
nitrogen than lucerne. Its biomass production was increased (from 9655 to 16
024 kg/ha) by full irrigation compared with partial irrigation, while
lucerne biomass similarly increased (from 6563 to 8040 kg/ha). Lablab also
fixed more nitrogen (177 kg N/ha) than lucerne (111 kg N/ha). Lucerne
used more water than lablab and thus lablab had higher water-use efficiency of
biomass production and nitrogen fixation. The study indicates that lablab
produces more green manure with greater water-use efficiency than lucerne
within a 1-year out-of-cotton rotation.
Additional tests on the effects of pesticides on cryptic species of blue oat mite (Penthaleus spp.) and the redlegged earth mite (Halotydeus destructor)
Authors: Robinson M. T. , Hoffmann A. A.
Published: September 2002

Earth mites (Halotydeus destructor, Penthaleus spp.) are
important pests of crops and pastures in southern Australia during the winter
and spring. A recent study showed that control of these mites is complicated
by different responses of species to several pesticides, with one cryptic
species (Penthaleus falcatus) being particularly
tolerant. In this study, earth mites were tested against 4 other chemicals
registered for mite control (alpha-cypermethrin, phosmet, chlorpyrifos and
lambda-cyhalothrin) in an attempt to identify useful pesticides to counter
control failures. Furthermore, an isolated population of an undescribed
cryptic Penthaleus species (P. sp.
x) from northern New South Wales was tested for its
response to 8 pesticides. Species responded differently to all pesticides.
Halotydeus destructor was usually the least tolerant
species except in the case of phosmet where P. major was
the least tolerant species. For alpha-cypermethrin and lambda-cyhalothrin,
tolerance of all Penthaleusspecies was similar or higher
than that of H. destructor. Penthaleus falcatus had a
relatively higher tolerance to phosmet than all other species. The response of
P. sp. x (New South Wales) to
chlorpyrifos was inconsistent between trials and the response of this species
to lambda-cyhalothrin was complex. Penthaleus sp.
x (New South Wales) was generally more tolerant than
H. destructor but not as tolerant as
P. falcatus. The results highlight the fact that mite
species need to be identified when considering control options and suggest
that effective control recommendations need to be developed for each
individual species.
Mitochondrial gene rearrangements as phylogenetic characters in the invertebrates: the examination of genome 'morphology'
Authors: Dowton M. , Castro L. R. , Austin A. D.
Published: September 2002

Mitochondrial gene rearrangements are the latest tool in the arsenal of phylogeneticists for investigating historical relationships. They are complex molecular characters that may provide more reliable evidence of ancestry than comparative molecular data. Here we review the phylogenetic utility of mitochondrial gene rearrangements, and find that despite isolated incidences of convergence, derived gene order appears highly congruent with phylogenies produced from other sources of data. We calculate that the chance of two mitochondrial genomes sharing the same derived genome organisation is only 1/2664, but caution that this ignores the possibility that the (as yet uncharacterised) gene rearrangement mechanism may greatly increase the chance of convergence. Broader taxonomic surveys of mitochondrial genome organisation will lead to a more realistic indication of the historical incidence of convergence in genome organisation.
An inordinate fondness for beetles
Authors: Grove Simon J. , Stork Nigel E.
Published: September 2002

In this paper we consider the extent of our knowledge of global beetle
diversity. Depending on the estimates adopted, some 70–95% of all
beetle species remain to be formally described, and at the current rate of
progress it could be more than 200 years until the task is completed. One of
the reasons for this is the difficulty of adequately sampling tropical beetle
faunas and thereby ensuring sufficient material is available to taxonomists
for comparative studies. Despite this, recent years have seen significant
advances in our understanding of beetle taxonomy, biology, ecology and
biogeography, and we are now in a good position to apply this understanding to
ecological and management issues. Saproxylic (dead-wood-associated) beetles
are used to illustrate this latter point.
The Psocidae (Insecta : Psocoptera) of Java and the eastern islands of Indonesia
Authors: Kentjonowati Endang Sri , Thornton I. W. B. , New T. R.
Published: September 2002

Seventy-one species of Psocoptera : Psocidae are recorded from Java and/or
the Lesser Sunda Islands, Indonesia, and their relationships and
distributional affinities are discussed. Keys are given to facilitate
identification of all genera and species from Indonesia together with a
regional checklist of species. New genera described and illustrated are
Anomaloblaste (two new species) and
Javablaste (two new species) of the subfamily
Amphigerontiinae and Javapsocus (four new species)
(Psocinae : Ptyctini). A total of 42 new species are described.
Review of the wolf spider genus Artoria Thorell (Araneae : Lycosidae)
Authors: Framenau Volker W.
Published: September 2002

The Australasian wolf spider genus Artoria, with
A. parvula Thorell, 1877 as type species, is revised in
part. In addition to A. parvula
(=A. luwamata Barrion & Litsinger, 1995, new
synonymy), recorded from the Philippines and Indonesia, and
A. palustris Dahl, 1908 from Papua New Guinea, it
includes the Australian A. albopedipalpis, sp. nov.,
A. avona, sp. nov., A. cingulipes
Simon, 1909, A. flavimanus Simon, 1909
(=Lycosa neboissi McKay, 1976, new synonymy),
A. howquaensis, sp. nov.,
A. lineata (L. Koch, 1877),
A. mckayi, sp. nov., A. quadrata,
sp. nov., A. taeniifera Simon, 1909,
A. triangularis, sp. nov.,
A. ulrichi, sp. nov. and
A. versicolor (L. Koch, 1877).
Artoriella flavimanus, the type species of
Artoriella Roewer, 1960, is returned to
Artoria. Of the remaining species of
Artoriella, the Western Australian species
A. cingulipes and A. taeniifera
are transferred to Artoria, the African species
Artoriella amoena Roewer, 1960,
A. maculatipes Roewer, 1960 and
A. lycosimorpha (Strand, 1909) are considered
incertae sedis and
Artoriella maura (Urquhart, 1891) from New Zealand is
considered a nomen dubium.
Trabaeola Roewer is a junior synonym of
Artoria, as its type species,
T. lineata, is transferred to
Artoria. Trabea australiensis (L.
Koch, 1877) is considered a nomen dubium. The genus
Artoria is characterised by a unique apophysis near the
base of the embolus of the male pedipalp. It does not fit into the existing
lycosid subfamilies, which have been established by investigation of mainly
Northern Hemisphere taxa. Artoria is widespread in
Australia and species can be found in a range of habitats (swamps and
riverbanks, open areas, rain and dry sclerophyll forests).
A revision of Brachyrhopala Macquart, an Australian region genus (Diptera : Asilidae)
Authors: Clements A. N.
Published: September 2002

The asilid
genusBrachyrhopala Macquart is revised; it currently
comprises two subgenera and 23 species. The following new taxa are described:
(i)Brachyrhopala (Vespina),
subgen. nov., of which
B.inopina(Walker) is designated
type species; (ii) in subgenus
Brachyrhopala(Vespina):
B. anomala, sp. nov.;
B. antennata, sp. nov.;
B. atra, sp.
nov.;B. bicolor, sp. nov.;
B. brunnea, sp. nov.;
B. grandis, sp. nov.;
B.melaena, sp. nov.;
B. mutabilis, sp. nov.;
B. unifasciata, sp. nov.; and
B. soluta solomonis, subsp. nov.;
(iii) in subgenus Brachyrhopala
(Brachyrhopala): B.
aurimaculata, sp. nov.; B.
danielsi, sp. nov.; B.
flava, sp. nov.; B.
nigra, sp. nov.; B.
ochracea, sp. nov.; B.
quadrata, sp. nov.; B.
rubrithorax, sp. nov.;B.
scutellata, sp. nov.. The following new synonyms are
proposed: (i) Brachyrhopala fenestrata (Macquart, 1850)
as junior synonym of B. ruficornis Macquart, 1847; (ii)
Brachyrhopala claviventris (Walker,
1861a) as junior synonym of
B. inopina (Walker, 1858); (iii)
Brachyrhopala indecora (Walker, 1865) as junior synonym
of B. semifilata (Walker, 1861b); (iv)
Brachyrhopala victoriae von Röder, 1892, as junior
synonym of B. ruficornisMacquart, 1847. The genera
Brachyrhopala and Cabasa Walker
form a genus-group within the tribe Dasypogonini.
Assessment of lateral compression of the idiosoma in adult water mites as a taxonomic character and reclassification of Frontipodopsis Walter, Wettina Piersig and some other basal Hygrobatoidea (Acari : Hydrachnida)
Authors: Cook David R. , Smith Ian M. , Harvey Mark S.
Published: September 2002

Systematists have frequently interpreted lateral compression of the idiosoma
in post-larval instars of water mites as a synapomorphy indicating common
ancestry. This paper re-examines the evidence to support this assumption and
concludes that lateral flattening has occurred independently several times
during water mite evolution, and especially often in various basal clades of
the superfamily Hygrobatoidea. Reassessment of the phylogenetic relationships
of the genera attributed to these clades results in improved understanding of
the early evolution and biogeography of hygrobatoid water mites and
necessitates redefinition of several clades and significant revision of the
family classification. The South African genus
Karlvietsia K.O. Viets, 1962 is transferred from the
subfamily Frontipodopsinae of the family Aturidae to the Hygrobatidae. The
Australian genera Tasmanaxona Cook, 1986,
Wheenyella Cook, 1986 and
Wheenyoides Harvey, 1990 are also removed from
Frontipodopsinae and placed with the genus Wettina
Piersig, 1892, here removed from the family Pionidae, in the family
Wettinidae Cook, stat. nov. Based on apparent
relationship with members of Wettinidae, the South African genus
Stormaxonella K.O. Viets, 1962 is transferred from the
Aturidae and provisionally placed in the Wettinidae. The clade including the
predominately Holarctic genus Lethaxona K.H. Viets, 1932
and the Western Hemisphere genus LethaxonellaCook, 1963
is recognised as the probable sister group of Wettinidae, and these genera are
consequently removed from the Aturidae and placed in Lethaxonidae, fam. nov.
The genus Frontipodopsis Walter is reassigned from
Aturidae to the now monobasic family Frontipodopsidae K.H. Viets, stat. nov.
Finally, five new species are described, including
Frontipodopsis (Frontipodopsella)
sudafricanus, sp. nov.,
Wettina occidentalis, sp. nov.,
Karlvietsia simplex, sp. nov.,
Hygrobates (Hygrobates)
gereckei, sp. nov. and Hygrobates
(Hygrobatides)frontipodoides, sp.
nov., and both Karlvietsia brevipalpis K.O. Viets and
K. angustipalpis K.O. Viets are redescribed.
Flow-rate requirements for captive western rock lobsters (Panulirus cygnus): effects of body weight, temperature, activity, emersion, daily rhythm, feeding and oxygen tension on oxygen consumption
Authors: Crear B. J. , Forteath G. N. R.
Published: September 2002

Oxygen consumption (Mo 2) of
P. cygnus was measured in intermittent flow
respirometers. A log–log relationship with body weight
(W ) remained constant over the range 15–31
°C. Mo 2 was related to
body weight and temperature (T) : log
10 Mo 2
=0.814log 10W +0.051
T – 2.075.I n 400 –500 g lobsters it showed
a strong response to acute temperature changes (23 –19 –15
–11 and 23 –27 –31 °C): log 10
Mo 2 = 0.045
T – 2.38. Activity caused a significant
(P <0.001) increase in
Mo 2, with the response being
modulated by temperature and body weight. Lobsters took 5–8 h to recover
from exposure to handling and emersion, the duration of the recovery period
being longer at higher temperatures. A nocturnal rhythm to oxygen consumption
was evident. There was a large and sustained specific dynamic action, with a
peak Mo 2 of 2.19 times the
standard rate occurring 7 h after feeding.
Mo 2 at 23 °C was
independent of the oxygen tension down to a critical oxygen tension
(P c) of 46.2 Torr, be low which
Mo 2 varied directly with the
oxygen tension. P c varied with
temperature and activity state. The data allow the design of live-holding
systems and practices that provide the oxygen requirements of captive
P. cygnus .
Extra keyword: live holding.
Range of electrosensory detection of prey by Carcharhinus melanopterus and Himantura granulata
Authors: Haine Olivia S. , Ridd Peter V. , Rowe Richard J.
Published: September 2002

Elasmobranch fishes have a well developed electrosense that is used for prey
detection. Research into the nature of bioelectric cues emitted by prey has,
however, been neglected, and consequently the spatial context in which the
electrosense operates to detect and home in on prey is not completely
understood. This study provided data on both ac and dc electric potentials
produced by teleost, crustacean and bivalve prey, as well as measured the
decay rates of electric field strength with distance. The electrosensitivity
of two tropical elasmobranch species was calculated to be ~4 nV
cm–1, from which it was calculated that these
predators probably detect their prey at a range of ~0. 25 m.
Allocation of effort in stream food-web studies: the best compromise?
Authors: Thompson R. M. , Edwards E. D. , McIntosh A. R. , Townsend C. R.
Published: September 2002

The amount and allocation of effort needed to characterize stream food webs
was investigated in five replicate streams. Two areas were considered:analysis
of community composition (number of individuals sampled)and of diets (number
of individuals gutted per animal taxon). Food webs were described by use of
consistent methodology, then the effort was retrospectively reduced by
considering half of the gut samples (halving dietary analysis effort)and by
successively reducing the number of individuals included. Food webs with a
reduced number of individuals overestimated connectance and prey:predator
ratios, and underestimated species richness, links per species and mean chain
lengths. These changes were due to loss of some invertebrate predator species
when effort was reduced. In contrast, for dietary analysis the amount of
effort expended on non-predatory invertebrates was more influential; halving
effort in dietary analysis of non-predatory taxa reduced estimates of
connectance and links per species. This study suggests that the effort needed
to produce a reasonable estimate is highly dependent on the food-web attribute
in question, and that aiming for equity of effort across taxonomic groups is
as important as expending greater effort in general.
Diet of Patagonian toothfish (Dissostichus eleginoides) around Macquarie Island, South Pacific Ocean
Authors: Goldsworthy S. D. , Lewis M. , Williams R. , He X. , Young J. W. , van den Hoff J.
Published: September 2002

A total of 1423 stomach samples were taken from Patagonian toothfish,
Dissostichus eleginoides, caught by bottom trawls at two
fishing grounds near Macquarie I., over three fishing seasons. Fish were
caught at depths ranging from 500 to 1290 m, and ranged in size from 310 to
1490 mm total length. The 462 stomach samples (32%) that contained prey
items indicated that toothfish preyed on a broad range of species including
fish, cephalopods and crustaceans (58%, 32% and 10%
biomass, respectively), suggesting that they are opportunistic predators. The
bathypelagic fish Bathylagus sp. was the most important
fish prey (14% dietary biomass); however, nototheniid, macrourid, morid
and myctophid fish were also taken. The squid
Gonatus antarcticus was also an important prey species
(16% biomass), and many other cephalopod species were taken in low
frequency. Prawnlike crustaceans (Nematocarcinidae, Mysididae, Sergestidae and
Euphausiidae) were the most important crustaceans taken (9% of prey
biomass). Significant inter-seasonal and inter-fishing-ground differences in
diet were found, but dietary composition was not related to fishing depth,
fish size (with the exception of one fishing ground in one season) or the time
of day of capture. Comparison with other studies reveals biogeographical
differences in the diet of toothfish.
Pelagic shark bycatch in the New Zealand tuna longline fishery
Authors: Francis Malcolm P. , Griggs Lynda H. , Baird Susan Jane
Published: September 2002

Tuna longline effort declined from 23—26 million hooks per year in
1979mdash;82 to 2mdash;4 million hooks per year in 1995mdash;98. Scientific
observer coverage averaged 7.5%since 1988mdash;89, but increased in
1992mdash;93 (mean 23%). Observed catch per unit effort (CPUE) and the
numbers of hooks set were used to estimate shark catches. Between 1988mdash;89
and 1997mdash;98,about 450 000 blue sharks
(Prionace glauca), 65 000 porbeagles
(Lamna nasus ) and 25 000 shortfin makos
(Isurus oxyrinchus) were caught. In 1997mdash;98,about
45 000 blue sharks, 4000 porbeagles and 3000 makos were caught. Corresponding
weight estimates were 1400 t, 150 t and 200 t. CPUE varied between foreign and
domestic vessels, between north and south regions and among years, but there
were no consistent temporal trends. Most males and females were immature, and
most sharks were alive when recovered. Most sharks were processed, but usually
only the fins were retained. The New Zealand tuna longline fishery is probably
not seriously affecting pelagic shark stocks, but adequate assessment is not
currently feasible. Accurate monitoring of Pacific Ocean catches is an
important first step towards ensuring sustainability of their populations.
Stress inhibition of reproductive endocrine processes in a natural population of the spiny damselfish Acanthochromis polyacanthus
Authors: Pankhurst N. W.
Published: September 2002

Stress–reproduction interactions were assessed by
in situ sampling and laboratory manipulation of fish
from a natural population of A. polyacanthus. Mean
plasma cortisol concentrations for fish sampled under water immediately after
capture were <11 ng mL–1 (range <1
to 42 ng mL–1 ); the variation was not a function
of disturbance before capture,with no differences in mean cortisol
concentrations between 5 min time blocks for chase times of up to 30 min. Fish
confined for 2 or 6 h after capture showed significant increases in plasma
cortisol concentrations, and depression of plasma T and E
2 in females and T and 11KT in males in summer but not
in winter. There was no correlation between plasma concentrations of cortisol
and sex steroids at capture. Underwater treatment of fish with cortisol had no
effect on brood-guarding behaviour.Injection of fish either at capture or 24 h
afterwards with human chorionic gonadotropin or luteinizing hormone-releasing
hormone analogue had no effect on plasma concentrations of gonadal steroids,
which remained low. Incubation in vitro of ovarian
follicles from these fish showed that gonadal tissue was still
steroidogenically active. This study suggests that inhibition of reproduction
by stress in spiny damelfish is above the level of steroid biosynthesis.
Consistency of faunal and floral assemblages within temperate subtidal rocky reef habitats
Authors: O'Hara T. D.
Published: September 2002

Habitats defined by various biological and environmental variables are
increasingly assumed to be surrogates for biodiversity. This study tested this
assumption for temperate subtidal rocky reefs off south-eastern Australia by
investigating the consistency of floral and faunal macrobenthic assemblages
within habitats defined by dominant vegetation, substratum lithology, depth,
wave exposure and region. Taxonomic groups included seagrasses, rhodophytes,
chlorophytes, phaeophytes, hydroids, bryozoans, molluscs, polychaetes,
pycnogonids and echinoderms. The results from multivariate statistical
analyses indicated that, although variation between replicate samples is high,
habitats as defined by dominant vegetation and, to a lesser extent, region
supported consistent floral and faunal assemblages. The patterns did not
emphasize a broad-scale biogeographic gradient, but rather the environmental
heterogeneity of the coastline at scales of 10–100 km.
Spatial variation in by-catch from a prawn seine-net fishery in a south-east Australian coastal lagoon
Authors: Gray Charles A.
Published: September 2002

Observer-based estimates of the catches and by-catches from prawn seining
(locally termed ‘snigging’) in Tuggerah Lake (NSW, Australia)
during the 1998/99 fishing season are presented. Observed catches included
three species of penaeid prawns, while observed by-catches contained a total
of 49 finfish and 5 invertebrate taxa. The overall by-catch:prawn catch ratio
by weight was 0.9:1, and in catching an estimated 20 ± 4 t of prawns
the fleet took an estimated total by-catch of ± 2 t throughout the
6-month fishing season. The by-catch included large numbers of small
(<15 cm total length) finfish species important in other commercial and
recreational fisheries, including
Gerres subfasciatus,Rhabdosargus sarba
and Acanthopagrus australis, as well as several small
demersal species of little economic value. Multivariate analyses indicated
that by-catch composition differed between seines taken over shallow seagrass
and bare substrata, with catch rates of several species being greater over
seagrass. It is recommended that strategies to reduce potential ecological
impacts and by-catch in this fishery be investigated, including fixed spatial
closures over seagrasses and the development of alternative fishing gears and
practices.
Influence of altered freshwater flow regimes on abundance of larval and juvenile Gilchristella aestuaria (Pisces : Clupeidae) in the upper reaches of two South African estuaries
Authors: Strydom Nadine A. , Whitfield Alan K. , Paterson Angus W.
Published: September 2002

Past investigations into South African estuaries that are subject to altered
freshwater flow regimes have concentrated on the effects of reduced river flow
on recruiting estuary-dependent marine fish species. This study compares
larval and juvenile abundance of an estuary resident,
Gilchristella aestuaria, in the upper reaches of the
‘freshwater-deprived’ Kariega Estuary and the
‘freshwater-rich’ Great Fish Estuary. Catches in the Kariega
Estuary were significantly greater than those in the Great Fish Estuary.
Larval and juvenile densities were correlated and regressed with salinity,
temperature, turbidity and river flow in each system. River flow was found to
be the most probable defining factor in terms of the contrasting catches in
these systems. G. aestuaria larvae and juveniles appear
to be flushed out of the Great Fish system as a result of the excessive amount
of river flow received from an inter-basin water transfer scheme. Although
freshwater input into estuarine systems is vital for the nursery function of
the lower reaches of South African estuaries, excessive supply can alter the
larval composition of estuary-resident fish species in the upper reaches.
Juvenile abundance both mirrors and masks a settlement pulse of the rock lobster Jasus edwardsii
Authors: Booth John D. , Stotter Dean R. , Forman Jeffrey S. , Bradford Elizabeth
Published: September 2002

Interannual changes in juvenile abundance can validate interannual changes in
levels of settlement on collectors and address such postsettlement processes
as density-dependent mortality. A strong pulse of
postlarval Jasus edwardsii recruitment took place near
Wellington in 1991–92, followed by much lower settlement. To determine
whether juvenile abundances by age would reflect this pulse and so validate
the collector catches, divers estimated quarterly the abundance and size of
juveniles at six sites, from 1993 to 2000. Juveniles younger than 2 years were
uncommon. At four sites, 2+ and 3+ lobsters were present in large
proportion until March 1995. From June 1995, most were at least 3+. These
data were consistent with progress of the 1991–92 modal group through
the age-frequency distributions, after which juvenile abundances declined,
thereby reflecting the settlement data. The other two sites differed in that
2+ and 3+ lobsters became more abundant with time. The reasons for
the disparity are unknown, but clearly sufficient site replication is needed
if juvenile year-class strengths are to reflect settlement patterns
accurately. Where pueruli are numerous enough to register on collectors,
crevice collectors appear to be more accurate and cost-effective in following
recruitment highs and lows than dive surveys.
Demographic characteristics of a selection of exploited reef fish from the Seychelles: preliminary study
Authors: Grandcourt Edwin Mark
Published: September 2002

The population biology of six commonly caught species in the Seychelles reef
fisheries was investigated by the study of otolith microstructures.
Alternating translucent and opaque bands were observed in transverse sections
of sagittal otoliths from Epinephelus chlorostigma,
Lethrinus lentjan,
Lethrinus mahsena, Scarus ghobban,
Scarus rubroviolaceus and
Siganus sutor. Evidence derived from two tagged fish
injected with tetracycline and recaptured after 1 year in the wild tentatively
suggests that opaque bands are formed on an annual basis in the otoliths of
L. mahsena. Species with a protogynous reproductive mode
had significantly female-biased sex ratios overall, but the bias was removed
in the older age classes apparently as a result of sex change. The results
demonstrate that for S. ghobban and
S. rubroviolaceus secondary males had accelerated growth
rates, but the phenomenon was not implicitly associated with a protogynous
mode of sexual development.
Temporal variation in the recruitment of larval fish into the Mhlathuze Estuary in northern KwaZulu-Natal, South Africa
Authors: Viljoen A. , Cyrus D. P.
Published: September 2002

In total, 136 taxa of larval fishes representing at least 49 families were
recorded in the Mhlathuze Estuary over one year. Community structure was very
similar to that found in a similar study at the adjacent Richards Bay Harbour,
with dominating families being the Engraulidae, Gobiidae, Sciaenidae and
Clupeidae. Marine-spawned larvae dominated the catch, with the most dominant
being euryhaline species that usually breed at sea and whose juveniles show
varying degrees of dependence on estuaries. High recruitment (238 per 100
m3 and 308 per 100 m3) occurred
during November 1998 and July 1999 respectively, these being the months of
lowest river discharge. Results indicated that a physical variable, in this
case river flow, is probably the forcing factor regulating spawning and
recruitment.
Summer fluxes of organic carbon and nitrogen through a damselfish resident, Stegastes nigricans (Lacepède, 1803), on a coral reef flat at La Réunion (Indian Ocean)
Authors: de Loma T. Lison , Harmelin-Vivien M. L.
Published: September 2002

In order to estimate the amounts of organic carbon and nitrogen flowing
through a herbivorous fish, ingestion, absorption, defecation and excretion
were studied in a widely distributed fish in coral reefs, the black damselfish
Stegastes nigricans. Two study sites were chosen on a
coral reef at La Réunion, in summer. One site is oligotrophic (site O),
while the other is nutrient-enriched (site D for disturbed), subject to
submarine groundwater discharges. Ingestion and defecation activities were
monitored by recording bites rates and faeces production, and excretion
quantified by in vitro experiments. Feeding activity (number of bites and
faeces) and individual trophic fluxes were larger at site D than at site O.
More algal food and thus more organic carbon and nitrogen were consumed,
absorbed and redistributed into the reef system by an individual fish at site
D than at site O, suggesting a positive feed-back of herbivores on
nutrient-enrichment.