South-eastem Australia Research Articles

Developments in passive seismic techniques through the ANSIR National Research Facility

Since 1997 the ANSIR Major National Research Facility has significantly enhanced Australia's national capacity for recording regional and distant earthquakes using seismic recorders distributed across the continent. Both broad-band and short-period recorders have been deployed in innovative experimental designs that have made major contributions to the understanding of the 3D structure in the Earth's crust and upper mantle beneath the Australian region. The Facility continues its national role with investment in equipment suitable for both seismic and electromagnetic sounding. Deployments of recorders with broad-band seismometers have made a substantial contribution to surface wave tomography, particularly with the gathering of extensive data sets from Westem Australia and a deployment bracketing the Tasman Line. The significant increase in the number of portable stations provides constraints on the character of the crust and the crust-mantle interface across the continent, via the analysis of receiver functions from distant earthquakes. Anisotropy beneath the continent is now better characterised but remains enigmatic. New analysis methods are likely to make more extensive use of continuous seismic data. Short-period instrument deployments have been mostly directed towards delay-time tomography studies in south-eastem Australia, and have employed new methods for event picking and tomographic inversion. Enhancements to the instruments mean that servicing of experiments will be simpler in future and allow new applications with three-component recording at higher sampling rates. Passive seismic recording offers a cost-effective way of obtaining structural information across substantial areas of the continent. The results are valuable in their own right, but can also provide important constraints on seismological structure that are valuable in planning more expensive deep crustal reflection profiles.

Holocene vegetation change in the mediterranean-type climate regions of Australia

In Australia mediteranean-type climates occur in southwestern Australia and in near coastal South Australia and adjacent western Victoria. These regions support species-rich sclerophyllous heaths and shrublands with the biodiversity particularly high in the southwest. Palynological records show that around the timne of the Last Glacial Maximum the climate was sufficiently severe that the vegetation of the southeastem regions was of a different character compared to today with grasses and Asteraceae more common everywhere. In the southwest the differences between Last Glacial Maximum and the Holocene were less pronounced and the tree and shrub genera Casuarina and Allocasuiarina were more prominent, and heathland and shrubland remaining the main vegetation type. Most of the records from the Last Glacial Maximun verify that common taxa in mediterranean-type climate environments today were present through that period in low niumbers. The modem chairacter of the vegetation developed arounid two key periods: the Pleistocene/Holocene boundary, and, to a much smaller degree, from the mid-Holocene, with the chaniges somewhat less in the southwest. The mid-Holocene period was mnarked by slightly wetter and waimer conditionis than present across all of southeastem Australia, yet most palynological records show little if any response in terrestrial vegetation in relation to this climate. The most significant Holocene changes appear to be a gradual decline in the importance of Casuarina, and changes in the abundance of Corymbia calophylla in the southwest. Many of the palynological records also have fossil charcoal histories and it is clear that, while there has been some regional variation. fire has been an important environmental feature of the regions throughout the Holocene. However, there are few indications that fire had any major role in vegetation change. What is clear is that European settlement, from about 150-180 years ago, wrought the greatest changes on vegetation, and possibly because of the parallel climate and environmental conditions the main invasive species have come from other mediterranean-type climate regions.

An Australian isolate of Alternaria crassa shows potential as a mycoherbicide to control the weed Datura stramonium

An isolate of Altemaria crassa obtained from Datura stramonium was tested for its potential as a mycoherbicide in south-eastem Australia. Sporulation of A. crassa in culture was greatest under the following conditions: on V-8 juice agar, with a 12 h photoperiod of ‘Warm White’ light, with cultures arranged in a monolayer, at 25–30°C, at about 13 days after inoculation. Spores rather than mycelial fragments were required to kill seedlings of D. stramonium. Preliminary experiments indicated that a minimum dew period of 9 h and a spore concentration of 105/mL were required to kill cotyledonary-stage seedlings of D. stramonium. In host range studies in the glasshouse, A. crassa killed or severely reduced the growth of all Datura species tested and other solanaceous weeds. Also, A. crassa caused disease symptoms on some crops and ornamental species, including four tomato and two eggplant cultivars, Petunia × hybrida ‘Mardi Gras’ and a soybean cultivar. Microscopic examination of the infection process after inoculation showed that spores germinated, formed appressoria and penetrated equally well on different species and so resistance was intracellular. This local isolate of A. crassa is potentially an effective mycoherbicide for D. stramonium and other solanaceous weeds in south-eastem Australia.

Use of fatty acid profiles and repetitive element polymerase chain reaction (PCR) to assess the genetic diversity of Pseudomonas syringae pv. pisi and Pseudomonas syringae pv. syringae isolated from field peas in Australia

Isolates of Pseudomonas syringae pv. pisi and P. syringae pv. syringae obtained from both plants and seed of field peas (Pisum sativum L.) in south-eastem Australia were compared using both fatty acid analysis and genomic DNA fingerprinting by repetitive element polymerase chain reaction (PCR). Fatty acid profiling was not specific enough to distinguish isolates of P. syringae pv. syringae from isolates of P. syringae pv. pisi and could not distinguish Races 2 and 6 of P. syringae pv. pisi from each other. DNA fingerprinting, however, was able to distinguish the Australian isolates of P. syringae pv. syringae from the isolates of P. syringae pv. pisi and group the isolates of P. syringae pv. pisi on the basis of race. DNA fingerprinting successfully identified the pathovar and race of unidentified and misidentified Australian isolates of P. syringae indicating that this method could be used as a rapid laboratory-based test for race determination of isolates of P. syringae pv. pisi. The genetic diversity within the isolates of P. syringae pv. pisi present within Australia is also discussed.

Roosting of the Sulphur-Crested Cockatoo Cacatua galerita

Sulphur-Crested Cockatoos Cacatua galerita may move considerable distances between night-time roosting sites and other areas where foraging takes place. Flocks may maintain a permanent roosting site and may occu- py it for many years (Lamm & Calaby 1970; Frith 1976; Taylor & COG 1992). In south-eastem Australia they roost in various trees including eucalypts, casuarinas, melaleucas and leptospermums (Lamm & Calaby 1970; Cooper 1975). We describe the night-time roosting be- haviour of C. galerita, the species of trees used and the characteristics of the remnant habitat patches occupied.

Dilophospora alopecuri on Lolium rigidum and Holcus lanatus in south-eastern Australia

The Anguina-vectored, plant pathogenic fungus, Dilophospora alopecuri, was collected at 41 of 156 sites examined in south-eastem Australia in the summer of 1995. D. alopecuri was found in Lolium rigidum in some areas of South Australia where populations of Anguina funesta/Clavibacter toxicus have resulted in outbreaks of annual ryegrass toxicity (ARGT) in livestock. The fungus was abundant in L. rigidurn, in western Victoria where A. funesta is common but ARGT outbreaks have not occurred. Infected Holcus lanatus was also collected in South Australia, Victoria and New South Wales. The significance of the findings for D. alopecuri as a naturally occurring and actively disseminated antagonist of C. toxicus is discussed. Additional keywords: biological control agent, geographic distribution

Correlations Between Carbon Isotope Discrimination and Climate of Native Habitats for Diverse Eucalypt Taxa Growing in a Common Garden

Distributions of common species of Eucalyptus in south-eastem Australia are related to gradients in temperature and rainfall. To determine whether intrinsic water-use efficiency (as indexed by carbon isotope discrimination, Δ) or other leaf attributes were related to climate of native habitats, we sampled 17 populations representing 14 species of Eucalyptus growing in a common garden in south- central New South Wales. Phreatophytes were clearly distinguished from populations that are totally dependent upon soil moisture derived from rainfall by having higher Δ at a particular level of rainfall. Among 12 non-phreatophytic populations (11 species), Δ was positively correlated with mean annual precipitation (r = 0.75, P = 0.005), December-March precipitation (r = 0.79, P = 0.002), an index of annual soil moisture (r = 0.81, P = 0.001) and seasonality of precipitation (r = 0.85, P < 0.001). There were similarly strong but negative correlations between Δ and potential evaporation during the summer months, but Δ was not correlated with annual potential evaporation of the source sites. Leaf mass per unit area (ρe) was negatively correlated with indices of water availability, positively correlated with nitrogen per unit leaf area (r = 0.90, P < 0.001), and negatively correlated with Δ (r = -0.73, P = 0.007). A was negatively correlated with area-based leaf nitrogen (r = -0.79, P = 0.002). These complementary correlations among Δ, ρe, and nitrogen per unit leaf area indicate that variation in Δ may stem largely from variation in photosynthetic capacity. The results provide strong evidence that variation in Δ and ρe reflect genetic adaptations to native habitats.

Taxonomic revision of Logania section Logania (Loganiaceae)

A systematic study of Logania R.Br, section Logania (Loganiaceae) is presented. This section consists of 21 species in Australia, occurring from Western Australia (as far north as North Cape, but mostly in the south-western regions of the State), southern-central and south-eastem South Australia, and eastern mainland Australia (from southern Queensland, throughout New South Wales and Victoria). Logania depressa, an imperfectly known and possibly extinct species from New Zealand, also appears to belong in this section. Logania archeri, L. litoralis, L. nanophylla, L. perryana, L. saxatilis and L. scabrella are described as new. A taxon within Logania albiflora s. lat. is here informally described as Logania sp. aff. albiflora because its taxonomic status is uncertain. Logania crassifolia R.Br. var. minor J. Black is here raised to specific status as Logania minor (J. Black) B. J. Conn. The status and taxonomic position of Logania imbricata, endemic to New Caledonia, are briefly discussed. Keys, descriptions, synonymy, illustrations and distribution maps are provided for all taxa in this section.

Reproduction in a Zebra Finch Colony in South-eastern Australia: the Significance of Monogamy, Precocial Breeding and Multiple Broods in a Highly Mobile Species

The reproductive demography of a colony of Zebra Finches Taeniopygia guttata was studied in farmland over four breeding seasons in south-eastem Australia. The colony was an open breeding assembly with much mobility of members. Breeding lasted from seven to nine months, spanning early spring to late autumn. Clutch size was smaller in the autumn half of the breeding season. Seed supplements did not affect clutch size. Clutches larger than modal size were the most productive. Re-nesting was frequent due to high nest predation (66%); losses between fledging age and independence were 69%. Young were capable of breeding at 60 to 70 days after hatching and their breeding success was no different from that of older birds. Young hatched in the spring half of the breeding season constituted 44% of pairs breeding in the autumn half of the season. Current breeding effort was traded-off against future breeding potential in young hatched in the autumn half of the season. Pairs mated for life (n = 144). The breakup of 50 pairs happened only on the presumed death of the partner; yet, repairing was frequent. Except for one brother-sister mating, mates were unrelated. Sexes did not differ significantly in natal dispersal, age at pair formation, number of mates acquired or breeding success. Estimates of 'lifetime' reproductive success were limited to the term a bird was present at the study colony and did not differ between the sexes. In their short, highly social and mobile lives Zebra Finches live in a state of tight, life-long social monogamy where high mortality is compensated for by multiple broods of mediumsized clutches produced by precocial, highly productive young.

Nodulation studies on legumes exotic to Australia: symbiotic relationships between Chamaecytisus palmensis (tagasaste) and Lotus spp

Strains of rhizobia were isolated from soil around the roots of tagasaste (Chamaecytisus palmensis) growing at 15 widely separated locations in south-eastem Australia. A further collection of strains of both Rhizobium loti and Bradyrhizobium sp. (Lotus) was assembled from 18 legumes including Lotus and other species symbiotically related to Lotus. The strains were used to inoculate tagasaste and 4 species of Lotus in experiments conducted under bacteriologically controlled conditions in a temperature-controlled glasshouse. Tagasaste formed nodules and fixed N2 with all of its homologous rhizobia but there was a wide range of effectiveness among the 15 strains. Tagasaste also formed nodules with each of the 18 strains from other species but fixed N2 with only 10. Four species of Lotus were inoculated with 3 tagasaste strains. One strain nodulated each species and fixed N2 with L. conimhricensis and L. corniculatus but not with L. parviflorus or L. pedunculatus. A second tagasaste strain formed nodules with all 4 Lotus spp. but did not fix N2, while the third nodulated only L. pedunculatus but did not fix N2. A pattern analysis based on the nodulating ability of the host plants in association with 21 strains showed that tagasaste and L. corniculatus formed 1 symbiotic group, and the other 3 Lotus species formed a third group. The pattern analysis procedure based on nodulating capacity of 21 rhizobial strains in association with the 5 host species indicated substantial symbiotic diversity within the collection, with the strains comprising 8 different symbiotic groups. No strain was highly effective on both tagasaste and any of the 4 species of Lotus. Data were insufficient to classify the root-nodule bacteria of tagasaste as either Rhizobium loti or Bradyrhizobium sp. (Lotus).

Four new species of Actaeciidae (Isopoda : Oniscidea) from Australia, with a review of the family

Four new species of Actaecia Dana are described from Australia; three of these (A. bipleura, A. cyphotelson and A. nasuta) are from beaches in south-eastem Australia and one (A. forrnida) is from the mid-eastern coast of Queensland. Specimens from Tasmania identified previously as Actaecia pallida Nicholls & Barnes belong to A. bipleura. The same probably applies to others from New South Wales and Lord Howe Island. The distributions of the six Australian species are noted. A review of the monogeneric family Actaeciidae includes a new diagnosis of Actaecia and a key to species. The distributions of the two New Zealand species are listed.

Ludwigia peruviana (Onagraceae) in the Botany Wetlands near Sydney, Australia

Ludwigia peruviana is an aquatic shrubby species introduced from the Americas and spreading to wetlands in coastal south-eastem Australia. It has become dominant, replacing much of the former vegetation in the Botany Wetlands, a series of shallow urban swamps and lakes near Sydney, Australia. Studies of L. peruviana were essential to the development of a management plan for the Botany Wetlands. Ecological studies were conducted in situ and supplemented by a series of germination and growth experiments in controlled environments. Flowering peaked in early autumn. Seed production for 1990-91 was ~ 450000 seeds m-2 and there was also ~ 65000 seeds m-2 in the soil seed bank and ~ 300000 seeds m-2 in old fruits that remained on the stems over winter. The seeds are ~ 0.8 mm long, weigh ~ 0.05 mg, are hydrophobic, usually germinate while afloat, and are easily dispersed by water, machinery and birds. Viability of fresh seed was 99% (tetrazolium dye test), and - 20% of seeds were dormant. Dormancy appeared to break down within two years. Propagation and dispersal may also occur by means of stem pieces that produce new shoots. New plants from seed, seedlings or stem fragments may become established on strand lines or form floating islands that may eventually become stranded. Management needs to focus on control of the seedlings and soil seed bank.

Geographical Differentiation in the Glossy Black-CockatooCalyptorhynchus lathami(Temminck) and its History

Geographical variation in the Glossy Black-Cockatoo Calyptorhynchus lathami is analysed. Two outlying regional populations, one in central east coastal Queensland and the other on Kangaroo Island, are shown to be morphologically separable from a core population through south-eastem Australia. The first is small in size and the second, also rather small, has a disproportionally large bill as well. Both are recognised subspecifically, the central east Queensland form being described as new. Late Cainozoic palaeogeography and climatic change are invoked to explain their likely origin, isolation and divergence. Implicafions for conservation are discussed.

Components of the fertiliser nitrogen balance for wheat production on duplex soils

In this paper, we review literature on the fate of fertiliser nitrogen (N) applied to duplex soils in wheat-growing regions of southern Australia, and discuss the contribution of specific N transformations to N loss. Duplex soils are characterised by the presence of soil material, within the rooting depth of crops, that possess hydraulic conductivities that are lower than those of overlying material. Denitrification and the transport of nitrate below rooting depth of crops are thought to be the chief causes of loss of fertiliser N and to contribute to poor grain yields. Ammonia volatilisation could contribute also to N loss. The fate of fertiliser N commonly applied to wheat in southern Australia has largely been evaluated using budgeting procedures using l5N, a stable isotope of N. Results from studies in south-eastem Australia, using red-brown earths, indicate that between 10 and 40% of applied 15N can be lost irrespective of time of application to wheat. Denitrification is believed to be the chief cause of loss of l5N. Similar studies on yellow duplex soils in Western Australia have shown fertiliser N loss to range from 70% to no loss of the l5N applied. The exact cause of N loss in Western Australian studies is unclear. There was circumstantial evidence for ammonia loss from surface-applied urea, and evidence of leaching of nitrates from this and other ammoniumbased fertilisers. The role of denitrification has not been clarified in Western Australian studies. In the majority of studies, recovery of 15N in aboveground biomass exceeded 40% of that applied. In addition, between 17 and 48% of applied 15N, of which 10-15% may be in root material, has been recovered in the soil organic matter pool. The predominance of the denitrification process in south-eastern Australian soils, and the inability to improve the efficiency of utilisation of 15N by delaying the time of application to wheat underscores the importance of controlling the nitrification process using inhibitors. Management options for Western Australian soils are less clear. Some agronomic experiments have demonstrated the advantage of delaying the application of fertiliser N to wheat to improve the efficiency of its utilisation. There is also evidence which suggests that N should be applied early in the growth cycle to promote tiller development and thereby increase the potential for grain yield.

Sea Temperature in Bass Strait and Breeding Success of the Little Penguin Eudyptula minorai Phillip Island, South-eastern Australia

Between 29 and 47% of the interannual variability in the weight and breeding success of the Little Penguin Eudyptula minor on Phillip Island, south-eastem Australia, was attributed, by correlation analysis, to monthly and inter-annual decreases in the east-west sea temperature gradient across Bass Strait. A station to the east, influenced by the East Australian Current, was generally about 2°C warmer than a station near the colony but these temperatures decreased, especially to the east, with the arrival of west winds. The correlations between physical and biological variables were consistent with the hypothesis that winds from the west bring cooler waters into and across Bass Strait, and that those cooler waters have slightly higher concentrations of nutrients or chlorophyll or more of the fish on which Little Penguins feed. The birds' biological response was measurable on a time scale of months: a decreased sea temperature gradient was associated with increased weights of adults four months later and a July-August decrease in sea temperature gradient was associated with an early start to egg laying in September-October.

Foraging Behaviour of Pardalotes in South-Eastern Australia: Comparison of the TaxaPardalotus punctatus, P. xanthopygusandP. striatus‘striatus’, ‘ornatus’ and ‘substriatus’

Two superspecies of pardalotes (Pardalotus striatus and P. punctatus) co-exist throughout south-eastem Australia with extremely high overlap in foraging behaviour. With data from seventeen sites, I examine this foraging behaviour and coexistence between these two superspecies and between taxa within the two superspecies. Foraging behaviours of three taxa within the P. striatus complex were virtually indistinguishable. The foraging of P. punctatus was very similar to that of P. xanthopygus, and there were no significant differences between the sexes of these spotted pardalotes. Spotted pardalotes foraged more at the periphery of foliage than did striated pardalotes, perched less often on twigs and branches but hovered more. This is related to the smaller size of spotted pardalotes. All taxa changed their foraging significantly between different study sites, and the direction of these changes were similar for all taxa. Local overlaps in foraging behaviour between the two superspecies were unrelated to local levels of prey abundance. There were some seasonal foraging changes that were consistent for all taxa. In winter, feeding rates increased and foliage extremities were used less often. Both spotted (particularly) and striated pardalotes changed foraging behaviours when in different tree species. These changes were correlated with differences in leaf size, leaf shape, tree height and densities of invertebrates and psyllids. Spotted and striated pardalotes were more segregated in tree species use than in type of foraging action.

Movements and Measurements of the Australian KestrelFalco cenchroides

Australian Kestrels are resident, partially migratory, dispersive and nomadic. Evidence was found of regular seasonal movements northward, especially, and coastally for the winter, out of the deserts for the summer, and down from higher altitudes in the south-eastem Australia for the winter. Australian Kestrels are irregular vagrants to many areas when conditions are favourable, regardless of season. Some differences in seasonal movements between age groups and sexes were found. Body weight was greatest in autumn. Slight geographic variation was found in body measurements. Wingspan, and perhaps tarsal breadth, provide the best means of separating the sexes using measurements. First year birds and adults can probably be separated in the hand, but not consistently in the field, using plumage differences.

A survey of Bladder Saltbush (Atriplex vesicaria Heward ex Benth) dieback on the Riverine Plain of south-eastern Australia from the late 1970s to 1983.

Bladder saltbush (Ahiplex vesicaria Heward ex Benth) is a valuable perennial chenopod shrub of the northem Riverine Plain of south-eastem Australia. From 1977 to 1983, dieback affected stands of this shrub over a wide area, reducing the drought reserves on many pastoral holdings. By early 1983 reports of new outbreaks of dieback had ceased, and by late 1983 regeneration, both vegetatively and from seedlings, was evident in most areas. This study reviews what is known of this dieback event. The extent of healthy bladder saltbush stands, pre-dieback and towards the end of the dieback period was mapped. It was found that the area of leafy bush had declined by 53 per cent, from 1.1 to 0.5 million hectares, by the end of 1983. There was considerable variation in timing, pattern and progress of dieback. The cause was not established.

Causes and Frequencey of Deaths among Birds Mist-Netted for Banding Studies at Two Localities

During studies of forest and heathland birds undertaken by the authors in south-eastem Australia, 53 (1.3%) of 4184 birds caught in mist nets died in the nets or when handled for banding. Mortality was higher in the study offorest birds, where 2.8% of individuals died, than in that of heathland birds, where 0.5% died. There was no relation between the size or kinds of birds handled and mortality. Instead, the difference between the two studies was probably the result of better procedures for handling birds in the heathland study. Causes of mortality, and ways to avoid or minimize injury to or death of birds during use of mist-nets, are discussed.

A Revision of the Austrlian Genus Epitymbia Meyrick, with Remarks on the Epitymbiini (Lepidoptera: Tortricidae)

Nine species of Epitymbia Meyrick are recognized in this revision: alaudana Meyrick [=periopa (Meyrick); =cydropis (Meyrick)], cosmota (Meyrick) [=heliochares (Lower), syn. nov.; =callizyga (Lower)], scotinopa (Lower), eudrosa (Turner), comb, nov. [=pyrrhocremna (Meyrick), syn. nov.], apatela, sp. nov., eutypa (Turner), sp. rev. and comb. nov., passalotana (Meyrick), comb. nov. [=semiophora (Turner), syn. nov.], dialepta, sp. nov., and isoscelana (Meyrick), comb. nov. [=thetis (Butler), syn. nov.]. One generic and three specific synonymies are confirmed and one generic and four specific synonymies are newly established. Two lectotypes are designated and four new combinations are proposed. All species except eudrosa, which is also found in New Guinea, are endemic to eastern and south-eastem mainland Australia and Tasmania, and known larvae feed on fallen leaves. Adults and genitalia of both sexes are figured, and heads, wing venation and other structures if relevant. The larval chaetotaxy is illustrated and the unusual biology is described. A tentative cladogram for the species of Epitymbia is given and the phylogeny of the genus is discussed with a view to clarifying the taxonomic status of the Epitymbiini.