Waterbird Dynamics in the RIchmond VAlley, New SOuth Wales, 1974-77

1983 ◽  
Vol 10 (2) ◽  
pp. 319 ◽  
Author(s):  
DG Gosper ◽  
SV Briggs ◽  
SM Carpenter

'Monthly waterbird counts from February 1974 to June 1977 at six wetlands in the Richmond River valley in northern coastal New South Wales were analysed to investigate relationships between numbers of each species, and season and water variables. Black swan, Pacific black duck, purple swamphen, dusky moorhen, cattle egret, comb-crested jacana and sharp-tailed sandpiper were strongly influenced by season. Grey teal, straw-necked ibis, little black cormorant, Pacific heron and black-winged stilt numbers were related to Murray River discharge, an index of inland wetland availability in New South Wales, northern Victoria and parts of southern Queensland. Numbers of most waterbirds were highest on the coast from late summer to the end of winter. Their seasonal abundance patterns conform with the results of some previous studies but differ somewhat from others.

1986 ◽  
Vol 13 (2) ◽  
pp. 213 ◽  
Author(s):  
LW Braithwaite ◽  
M Maher ◽  
SV Briggs ◽  
BS Parker

Populations of waterfowl of three game species, the Pacific black duck Anus superciliosa, grey teal A. gibberifrons, and maned duck Chenonetta jubata, were assessed by aerial survey in October 1983 within a survey region of 2 697 000 km2 of eastern Australia. The numbers of each species were assessed on all surface waters of over 1 ha, and on a sample of smaller surface waters within 10 survey bands each 30 km wide and spaced at intervals of 2� latitude from 20�30' to 38�30'S. The area within the survey bands was 324 120 km2, which gave a sampling intensity of 12.0% of the land surface area. The area of features shown as wetlands or water impoundments within the survey bands on 1 : 2 500 000 topographic maps was 19 200 km2 or 11.2% of the total area of these features in the survey region. The area of surface waters surveyed was assessed at 465 300 ha. Assessments of populations of each species were tallied for wetlands by grid cells of 6 min of 1� longitude along the survey bands (258-309 km2 depending on latitude). Distributions were then mapped, with log*10 indices of populations in each cell. Distributions of the black duck and grey teal showed a pattern of intense aggregation in limited numbers of cells, that of the maned duck was more evenly distributed. The major concentrations of the Pacific black duck were recorded in northern New South Wales and the south-eastern, western, central eastern and central coastal regions of Queensland; those of the grey teal were in south-western, western and northern New South Wales and central-eastern Queensland; the maned duck was broadly distributed over inland New South Wales with the exception of the far west, inland southern Queensland, and central northern Victoria.


1979 ◽  
Vol 6 (3) ◽  
pp. 319 ◽  
Author(s):  
GN Goodrick

The study area of 500 km2 was humid and subtropical, on flood plain near Coraki, New South Wales. Gut contents were examined and the percentage by volume of different food items is tabulated for black duck (Anas superciliosa) and grey teal (A. gibberifrons). Black duck fed on flooded meadow-grass flats in autumn, moving when the flats dried to seasonal swamps, and when those also dried, to lagoons. Diet varied with place. Seeds of grasses, swamp plants and lagoon plants were eaten, with water snails and water beetle adults and larvae, water spiders and ostracods, and terrestrial invertebrates being eaten when the dry flats became flooded. They ate also waste maize grain from harvested fields before ploughing. Grey teal fed in the seasonal swamps in winter and then left the area almost completely; they ate almost the same items as black duck but fed by the muddy edges of seasonal swamps more than the black duck did. It was known that black duck strip seed from the growing plant and grey teal pick up the fallen seed.


1989 ◽  
Vol 40 (3) ◽  
pp. 605 ◽  
Author(s):  
KA Archer ◽  
GG Robinson

This paper reports the findings of a five-year study on the growth patterns, production and means of persistence of white clover in a cool temperate environment with summer dominant rainfall, on the Northern Tablelands of New South Wales. White clover essentially persisted as a perennial, but large and rapid declines in plant frequency occurred during late summer if soil moisture levels became depleted. The critical combination of conditions at which plant frequency was adversely affected occurred when available soil moisture levels declined below 35 mm and mean weekly maximum temperatures exceeded 20�C; conditions which often occur in late summer in this environment. During one prolonged period of moisture stress in the second spring and summer period of the study, all plants died. Regeneration was due to germination of seeds and seedling establishment, but plants subsequently persisted as perennials. Relationships were developed to predict the probability of survival of white clover over the range of temperatures and soil moistures recorded in these experiments. Germination occurred to a variable extent each year, but was observed only during winter and spring. Seedling establishment was effective in only one year, which followed the death of white clover in summer, 1980-81. The sward was slow to recover after seedling regeneration owing to low winter temperatures and competition from established temperate perennial grasses in spring. Seedlings contributed little to dry matter production in spring. These results indicate that white clover is unlikely to be of value as an annual in temperate pastures. Strategies aimed at improving white clover in cool temperate environments, either by management or selection/breeding programs, should therefore focus upon improving the ability of white clover to persist as a perennial.


1990 ◽  
Vol 41 (3) ◽  
pp. 411 ◽  
Author(s):  
FR Roubal

Seven monogenean, 1 digenean and 9 copepod species of ectoparasite were found on 179 juvenile Acanthopagrus australis collected bimonthly over two 12-month periods from a small estuary at Red Rock in northern New South Wales. The monogenean Allomurraytrema spari and the copepod Alella macrotrachelus showed a consistent cycle of spring-summer high and late summer-autumn low in prevalence and intensity of infection, whereas the digenean Prototransversotrema steeri was present only in winter. The monogenean Haliotrema spariensis was highly prevalent year-round, but other monogeneans were inconsistent in seasonal prevalence and intensity. The copepods Paraergasilus acanthopagri and Dermoergasilus acanthopagri showed inconsistent annual cycles, but their fluctuations in prevalence and intensity were nearly identical. The other species of ectoparasite had no consistent cycles or were rarely found. Temperature does not appear to directly regulate the abundance of ectoparasites on juvenile Acanthopagrus australis in Red Rock estuary.


1972 ◽  
Vol 12 (59) ◽  
pp. 584 ◽  
Author(s):  
WR McManus ◽  
TG Kennedy

Merino ewe weaner lambs grazing at a high stocking rate for 32 weeks in the Wellington region of New South Wales were fed two levels (low, medium) of oat grain plus lucerne hay supplement. Insignificant fleece-adjusted liveweight gain and significant, but small, (2.8 per cent and 9.9 per cent) increases in clean fleece weight resulted for the low and medium groups. Feeding reduced fleece tenderness and altered wool handle and colour. Merino weaner ewes grazing improved pastures at Yass were supplemented with oat grain for 12 weeks in the late summer-early autumn. There was a temporary increase in woo1 production and liveweight but subsequent fertility was not improved. The responses obtained to treatment in both trials appear to be uneconomic


1974 ◽  
Vol 14 (68) ◽  
pp. 405 ◽  
Author(s):  
MH Campbell

In three experiments near Rockley and Gunning, New South Wales, non-arable areas of serrated tussock (Nassella trichotoma) were aerially sprayed with 2,2-DPA in late summer and, in the following autumn, aerially fertilized and sown with pasture species. Measurements of tussock density and the botanical composition of the pastures were made for up to ten years after sowing. The experiments commenced in 1963, 1964 and 1966. About 90 per cent of the tussock plants were killed by applying the herbicide at 16.6 kg a.e. ha-l; higher rates effected little improvement. Aerially sown pastures further reduced tussock numbers and provided long term control. Best results were obtained on fertile soil and where tussock has not been retarded by burning. Of the pasture species sown Trifolium subterraneum and Phalaris tuberosa were the most effective for long term control.


1965 ◽  
Vol 5 (16) ◽  
pp. 91
Author(s):  
D Leggo ◽  
JA Seberry

Diphenyl wraps and diphenyl liners in combination with sodium a-phenylphenate and borax-boric acid dips were compared for control of green mould in stored oranges. Four experiments were carried out in the Sunraysia area on the Murray River in 1959 and three at Gosford on the central coast of New South Wales in 1960 and 1961. Treatment of the fruit with sodium o-phenylphenate, combined with the application of diphenyl, whether impregnated in fruit wrappers or case liners, effectively reduced green mould in oranges stored at atmospheric temperatures for periods up to nine weeks. There were indications that the location of the diphenyl-impregnated case liners within the container is an important factor in the efficiency of mould control by these treatments.


1984 ◽  
Vol 11 (3) ◽  
pp. 559 ◽  
Author(s):  
CG Barlow ◽  
K Bock

The effect of cormorants on the survival of native warm-water fishes in farm dams in south-western New South Wales was monitored during 1979 and 1980. Three species of cormorants frequented the dams: the great cormorant Phalacrocorax carbo, the little pied cormorant P. melanoleucos, and the little black cormorant P. sulcirostris. In dams fished by cormorants, more than 50% ofthe fish were consumed unless abundant alternative prey, in this case crayfish Cherax destructor, was present. Dams stocked with few fish (approximately 150 ha-1) were less commonly fished than those stocked with many fish (more than 450 ha-1). The majority of dams in the study area were fished by cormorants, which were present from midwinter to midsummer in both years. The results, and an examination of aspects of cormorant biology and methods used to prevent birds eating fish at hatcheries, indicated that buffer populations of crustaceans and low fish stocking rates are suitable methods for minimizing predation of fish in farm dams by cormorants.


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