Late Silurian trilobites from central western New South Wales, with revision of Batocara rothwellae (Encrinuridae) and Denckmannites rutherfordi (Phacopidae)

An important outbreak of the Australian plague locust, Chortoicetes terminifera (Wlk.), occurred in 1973 in central western New South Wales. The dynamics of the outbreak could be resolved into a sequence of five principal interacting events: (1) Sustained population increases in low-density populations in northern central western New South Wales during three successive breeding periods in 1972. The increases were a result of successful, local multiplication, immigration from more northerly breeding areas and restricted opportunities for dispersal. The continuing concentration of locusts in the northern central west led to local gregarisation and swarm formation in autumn and spring 1972. (2) Massive southward displacements at night during an intense tropical disturbance between 29 January and 4 February 1973, which resulted in an invasion and concentration of infestations in southern central western New South Wales. (3) Substantial multiplication increases (10- to 30-fold), as a result of the drought-breaking rainfall in the autumn and spring of 1973 in the central-west. This resulted in an intensification of the plague with the production of numerous, slow-moving swarms. (4) Massive southward displacements during several periods of disturbed weather in spring 1973, which led to the disappearance of adult infestations from the central west and a dispersal of infestations in areas invaded further south. (5) Heavy mortality in residual populations of hoppers and eggs. The combined effects of parasites, predators and a reduced viability of eggs and hoppers resulted in a complete collapse of the plague in the central west by December 1973.Although displacement by adults at night is shown to be the principal factor regulating both population fluctuations in specific localities and the spread of plagues through southward invasions, outbreaks are ultimately determined by initial multiplication increases in relatively sedentary recession populations. Both multiplication and migration were influenced more by variations in synoptic weather than by any other factor. Diurnal swarm movements, although conspicuous, did not significantly influence the overall spread of the outbreak studied.The quality and quantity of available fresh green food did not appear to limit further successful breeding during the decline of the plague. Although influxes of locusts into the central-west continued during disturbed weather in 1974, none remained to breed and densities fell to levels (<1/ha) lower than those of drought seasons. It appears unlikely, therefore, that plagues can be sustained in any one area, even when environmental conditions remain favourable for breeding, because of: (1) mass emigration during disturbed weather; (2) increased effectiveness of natural enemies; and (3) declines in viability and fecundity in moist conditons.

Paleoecological interpretation and age of an interstadial lake bed in western New York

Globally significant geoheritage features of the Cliefden Caves area, in the Belubula River Valley between Orange and Cowra in central western New South Wales, comprise a richly fossiliferous shallow-water limestone succession of Late Ordovician age (the Cliefden Caves Limestone Subgroup) overlain by deep-water laminites and allochthonous limestones of the Upper Ordovician Malongulli Formation. Key features of the Ordovician geology of the Cliefden Caves area that have been identified using the Geoheritage Toolkit as being of international significance are the abundance of unique and exceptionally diverse fossils in the Fossil Hill Limestone (forming the lower part of the Cliefden Caves Limestone Subgroup), which supplement detailed interpretation of carbonate-dominated deposition within an Ordovician volcanic island setting. The fossiliferous limestones preserve biostromes and local small bioherms of stromatoporoids and corals, and recurrent in situ and disarticulated/imbricated Eodinobolus shell beds formed in shallow, quiet-water, dominantly muddy carbonate sediments that passed up-sequence to clay-free carbonate environments. These mud-dominated carbonate sediments are interspersed with higher-energy conditions, represented by skeletal, lithoclastic and calcrete-ooid grainstones overlying disconformities, leading to the identification of subaerial disconformities and associated diagenesis in the Fossil Hill Limestone. The Fossil Hill Limestone is succeeded by massive limestones in the middle part of the Cliefden Caves Limestone Subgroup and then, in turn by the Vandon Limestone and the deeper-water graptolitic laminites of the Malongulli Formation—this completes a succession that is rarely preserved in the geological record, further enhancing the geoheritage significance of the Cliefden Caves area.

Agricultural production systems that also provide opportunities to conserve biodiversity will be a crucial component of integrated and sustainable land use in mixed farming landscapes and should be considered and evaluated. Alley farming is an innovative farming system that aims to increase farm profitability while also enhancing environmental outcomes. Alley farming incorporates belts of woody perennial plants such as trees or shrubs, interspersed with alleys of conventionally rotated cropping and livestock grazing land. In the present study, we assessed the impacts on terrestrial biodiversity of alley farming with the native perennial chenopod shrub old man saltbush (Atriplex nummularia Lindl.) in central western New South Wales. Terrestrial biodiversity conservation status was assessed by site surveys conducted in spring 2005, 2006 and 2007 at 15 old man salt bush alley farming sites (OMSB), 15 conventionally managed sites and three native woodland remnants in and around the Condobolin Agricultural Research and Advisory Station in the central western plains of New South Wales. Biodiversity surveys included an assessment of ‘site condition’ – a metric of biodiversity conservation status at the site scale based on measurement of 10 habitat and vegetation condition attributes, compared against benchmark values for the appropriate native ecosystems with relatively little recent anthropogenic modification. Bird surveys were also conducted to assess the diversity and abundance of birds in OMSB, conventional and remnant woodland sites in four functional response groups. Site condition was significantly higher at remnant woodland sites than at conventional farming and OMSB alley farming sites. Remnant woodland sites had greater native overstorey cover and native ground cover of forbs, more trees with hollows, presence of at least some overstorey regeneration and the presence of fallen logs. Site condition was also significantly higher at OMSB sites than at conventional sites and increased significantly across 3 years. By the third year after establishment, OMSB sites had higher native plant species richness and native mid-storey cover than did conventionally farmed sites. These attributes increased markedly over time at the OMSB sites whereas they did not increase at conventional or remnant woodland sites. Native grasses and forbs established under and around the saltbush plants, indicating that OMSB alley plantings can provide habitat for a wide range of native plant species, enhancing biodiversity values of these areas through improved structure and composition. Improved habitat condition at the OMSB sites after 3 years did not lead to a significantly higher diversity or to a higher overall abundance of birds at the OMSB than at conventional sites. Furthermore, diversity and abundance of birds at both OMSB and conventional sites remained significantly below those of remnant woodland sites. Some decliner bird species were observed using OMSB sites, but not conventional sites. Old man saltbush alley farming can provide direct on-site benefits for native biodiversity by improving the structure, function and composition of vegetation at the site or paddock scale. If proposed as a replacement to conventional crop–pasture rotation, OMSB alley farming can enhance biodiversity conservation values, and where production benefits are likely, could play an important role in the integration of production and conservation as a synergistic ‘win–win’ system in mixed farming enterprises.

On three adjacent experimental plots in central western New South Wales, from 1971 to 1974, population fluctuations of the Australian plague locust were interpreted in terms of the interactions between reproductive rates (Ro) between generations and net migration losses or gains (M plus or minus ) within generations. Changes due to variations in net migration fluctuated over a greater range than those due to variations in reproductive rates, and were the major cause of the population fluctuations during the 16 generations studied. Variations in rainfall during breeding accounted for nearly 90% of the variance in reproductive rates, provided rain followed relatively dry periods. Changes caused by migration resulted from episodic, often long-range and generally southward displacements of adults at night in the gradient wind during disturbed weather. The frequency and intensity of migration depended primarily on the availability of potential emigrants and secondarily on the incidence of weather favourable for takeoff and prolonged flight. The incidence of rainfall before periods of migration was higher than expected. Adults thus migrated into areas already favourable for successful breeding. Long-term median rainfall during breeding at Trangie gave mean reproductive rates greater than 1 per generation. Hence, population surpluses tend to be produced and generally disperse south to areas less favourable for breeding. There was close correspondence between the occurrence of heavy drought-breaking rains, leading to substantial population increases and migrations, and the observed incidence of outbreaks in this area. Changes in the relative importance of reproduction and migration in the drier breeding areas further inland are discussed in relation to historical changes in the distribution and abundance of the plague locust.

Summary Unlike parts of Victoria and South Australia, direct seeding of woody plants has been unreliable in Central Western New South Wales where failures have been attributed to low rates of seedling emergence and competition from herbaceous weeds. We investigated the usefulness of overspraying newly emerged seedlings of eucalypt (Eucalyptus spp.) and Narrow‐leaf Hopbush (Dodonaea viscosa ssp. angustissima) in an existing or potentially weedy seedbed using a grass‐selective herbicide (Fusilade® or Sertin®) and/or a soil‐residual herbicide (Simazine®). These treatments were investigated at two sites over three sowing seasons in Central Western NSW. In most cases, the herbicides failed to enhance seedling survival because grasses were not the main component of the weed species present or because the herbicide damaged the seedlings. Hopbush was relatively tolerant to Simazine but eucalypt seedlings were not, particularly at the site with sandy soils. Grass‐selective herbicides did not appear to damage seedlings. Suggestions for increasing the reliability of direct seeding in this region are presented.

Dry matter production and seed yields of a range of annual legumes grown in ungrazed swards were measured between 1966 and 1971 on seven sites in the low rainfall wheatbelt of central western New South Wales. Jemalong and Hannaford barrel medics (Medicago truncatula) were the highest yielding medic cultivars tested. Jemalong medic was slightly superior to Hannaford in dry matter production but seed yields were equal. The short season subterranean clovers (Trifolium subterraneum), Dwalganup and Geraldton, yielded much less dry matter and seed than the medics in most experiments. Although the mid-season subterranean clovers, Woogenellup and Clare, persisted for the duration of our experiments, their production was not as consistent as that of the medics, and plant densities decreased. The rose clovers (T. hirtum), Sirint and Kondinin, the cupped clovers (T. cherleri), Beenong and Yamina, and Snail (M. scutellata) and Paragosa (M. rugosa) medics did not produce satisfactory swards.

The system by which different tribes of Aborigines in central western New South Wales classified themselves according to the language they spoke and the territory they lived in is analyzed. Examples are provided as to how their names were based on their language, and their varied names were indicative of their tribes and their territories.

Reworked conodonts, extracted from calc-lithic horizons within the Late Devonian Catombal Group, central western New South Wales, are identified as being derived from horizons correlated with the following Silurian zones: Kockelella amsdeni, Pterospathodus amorphognathoides, Distomodus staurognathoides and possibly Distomodus pseudopesavis and Distomodus combinatus. Several Ordovician elements were also recovered but only a broad Middle to Late Ordovician age can be determined. Comparisons of these faunas with those documented from the general region indicate a probable source from limestone sequences to the south, between Orange and Cowra.

A natural pasture consisting predominantly of Aristida, Stipa, Danthonia and Chloris was grazed by Merino wethers set-stocked at 2.04, 1.36 and 1.02 ha-1 at Condobolin in central western New South Wales. Throughout the four years 1965 to 1969, the pasture supported 1.36 wethers ha-1 without supplementary feeding. Wool production per ha increased with increase in stocking rate but wool production per head and liveweight decreased. Although there was a greater percentage of annual medics at the high compared with the low stocking rate, the high stocking rate reduced total ground cover and the density of Aristida.

Summary. The light-textured, red, gradational and duplex soils in semi-arid central western New South Wales were found to be on a pH threshold for suitability for the traditional cultivars of barrel medic (Medicago truncatula), an important pasture legume in the region, and other acid sensitive species. However, there was little evidence that cropping over a long time increased soil acidity. Over the 38 sampling sites, mean pHCa in the soil surface 0–20 cm was significantly higher in cropped compared to contiguous uncropped and usually timbered control areas. The return of cations and associated alkali in standing timber to the soil surface when trees were pushed and burnt is a plausible explanation. In the surface (0–20 cm) layers of 10 of 38 cropped paddocks, mean pH in 0.01 mol CaCl2/L was <5, sufficient to severely obstruct growth and the nitrogen fixing capacity of barrel medic. All but 4 sites had pHCa <6, where some reduction in nitrogen fixation would be expected to occur. Variation in pH within transects within paddocks was large, which is consistent with the common observation of poor and patchy growth of barrel medic. Exchangeable calcium, important for Medicago–Rhizobium meliloti symbiosis function, decreased with increasing acidity. The potential for manganese toxicity appeared low with aluminium toxicity likely only at some sites with pHCa ≤4.5. Total carbon decreased with increasing soil acidity and was less under cropping at any pHCa. Although acidification of these soils due to agricultural activity was not apparent from paired sampling of cropped and contiguous uncropped transects, they seem likely to be prone to acidification.

Unrealized natality and mortalities at successive development stages were measured during synchronized breeding by populations of the Australian plague locust. Studies were made over a 3-y period, covering nine generations, on small plots situated in pastures derived originally from savannah woodland in central western New South Wales. Variations in natality and mortalities were influenced more by variation in soil moisture, primarily through its effect on pasture conditions, than by the effects of natural enemies; these variations were closely correlated with seasonal rainfall. Unidentified losses, independent of known variables, were recorded in the hopper stage and were highest in the hatchling. Such losses invariably exceeded 60% even under the most favourable conditions encountered in the field during the study period. The quantitative relationships established in this study between the plague locust and its natural enemies and other environmental factors suggest that prospects for the biological control of this pest by either native or introduced species are poor.

The ovaries from slaughtered Peppin Merino ewes were examined at Trangie for a 12 month period commencing in April 1954. A seasonal rhythm was demonstrated for the percentage of ewes ovulating and for the percentage of multiple ovulations. The seasonal peak was in March–April, with a trough in November–December. Data were compared from a series of autumn and spring matings over the years 1953–1959 using genetically comparable flocks of similar age distribution, mated by identical methods. The overall incidence of oestrus was significantly higher in the first 3 weeks of mating (artificial insemination) in the autumn. The patterns of incidence of oestrus also differed, oestrus being much higher at the commencement of mating in the autumn. Differences between years in the incidence of oestrus were more pronounced in the spring, low incidence being correlated with poor nutrition. In only one mating — spring of 1954, a drought year — was the incidence of oestrus low initially, with a sharp rise commencing at 14 days. The conception rate for autumn-mated ewes was 10 percent. higher than for spring-mated ewes. Little difference was observed in the number and motility of sperm used at the seasonal matings. Lambing percentages strongly favoured the autumn mating: 15 percent. more wet ewes, 25 per cent. more twins mothered, 37 per cent. more lambs mothered, and 33 per cent. more lambs weaned. There was little difference between seasons in ewe deaths prior to and during lambing, or in deaths of lambs between mothering and weaning. The relative importance of the factors causing the 37 per cent. more lambs mothered in the autumn mating was as follows: incidence of oestrus, 11 per cent.; pattern of oestrus, 5 per cent.; incidence of multiple ovulation, 57 per cent.; conception rate, 27 per cent. The importance of the conception rate could be largely an associated effect of the higher autumn incidence of multiple ovulation. The weaning weight of lambs tended to be slightly higher for autumn matings, although there was great variation between years, both in the size and in the sign of differences. These differences had almost disappeared by 17 months of age. The choice of a mating time in central western New South Wales is discussed relative to these findings.

Red cell antigen, serum protein and red cell enzyme groups were determined for a series of 1,821 individuals belonging to six language families in Western New Guinea. Three of the language families represent groupings of languages spoken by people in the swampy coastal plain of south central Western New Guinea, two belong to the Central Highlands and one to the Lake Plain area near the confluence of the Idenburg and Rouffaer Rivers.The distribution of genetic markers reveals similarities with other parts of New Guinea. The A2 allele is absent in the ABO system, the frequency of Ns in the MNS system is very high as is the R1 (CDe) allele in the Rh system. Hp1 frequencies are high, and the transferrin allele TfD1 is present as in other parts of New Guinea. In the red cell enzyme systems several alleles were detected which are characteristic of Papuan, and in some cases other Melanesian populations: these include MDH3, PGK4, PGK2, PGM92, PGM102, as well as some very restricted alleles such as Peptidase B6 and Pep B2.Three indices of genetic distance were computed. The most striking results are the genetic closeness of the Dani and Moni populations from the Central Highlands to the Asmat on the southern coastal plain, and the relative remoteness of the Awyu from the other south coastal populations. The results are discussed in terms of recent theories on the origin and dispersal of Papuan languages.

Eleven species of native grass were collected from 51 sites throughout western New South Wales and south-west Queensland. Approximately 10 whole plants of each species were collected from a site but not all species were collected from each site. Plants were grown in a common environment at Trangie in central western New South Wales and plant morphological and floristic characteristics measured. Data reported here are for observations made in the third year, by which time differences between populations were likely to be more genetic than environmental. Principal component and discriminant analyses revealed a strong relationship between site of origin and plant morphological characteristics, which explained between 61% and 93% of the variation within species. For all but one species, site was significantly correlated with these morphological characteristics. Site could be predicted from morphological characters with a success rate usually greater than 80%. These morphological characteristics must reflect genotypic differences among the collection from the different sites. We were unable to relate this variation to any of a range of site characteristics. Distance between sites could not be used as an indicator of morphological differences between populations. The implications of these findings are discussed in terms of providing strong evidence for the existence of ecotypes and for obtaining appropriate seed sources for revegetation/restoration programs.