Intertidal algal species diversity and the effect of pollution

1972 ◽  
Vol 23 (2) ◽  
pp. 73 ◽  
Author(s):  
MA Borowitzka
Keyword(s):  
Species Diversity ◽  
Species Composition ◽  
New South ◽  
New South Wales ◽  
Algal Species ◽  
Maximum Value ◽  
South Wales

The species diversity of the larger intertidal algae was determined at three sites along the coastline of Sydney, New South Wales. The changes in species diversity and species composition were correlated with height from mean of low water (MLW), distance from the edge of the rock platform at MLW, and distance from a sewer outfall (i.e. the degree of pollution). The total number of algal species was reduced in the vicinity of the outfall. This reduction was most evident in the Phaeophyceae and the Rhodophyceae. The maximum value of algal species diversity was also reduced at higher levels above MLW, away from the edge of the platform and near the outfalls.

Avian use of farm habitats, including windbreaks, on the New South Wales Tablelands

2004 ◽  
Vol 10 (3) ◽  
pp. 180 ◽  
Author(s):  
DR. Cilla Kinross
Keyword(s):  
Species Composition ◽  
Native Species ◽  
New South ◽  
New South Wales ◽  
Bird Species ◽  
Agricultural Landscapes ◽  
Canonical Variate ◽  
Bird Conservation ◽  
Avian Diversity ◽  
South Wales

Many windbreaks are being planted on the Tablelands of New South Wales, Australia to provide shelter for stock and crops, but little is known of the effect of these linear plantations on the regional bird community. This paper compares the avian diversity, density and species composition in a range of habitats in agricultural landscapes, including farm windbreaks, and draws conclusions as to the benefits of windbreaks to bird conservation. The data were collected between 1993 and 1997 with 12 visits to each of 84 sites, placed a priori into seven habitat types on six grazing properties in the Tablelands of New South Wales, Australia and analysed using ANOVA and canonical variate analysis to identify bird-habitat relationships and patterns. Species diversity and density were found to be highest in remnant woodland and lowest in grassland, but differences between other habitats were less robust. Windbreaks >19 m wide were closer in diversity and species composition to remnant woodland than windbreaks =15 m wide. Of the 105 bird species observed, 17 were confined to remnant woodland and 67 native species were observed using planted sites. These species were not, as had been predicted, entirely composed of generalist-opportunistic species, but, particularly in the wider planted sites, included several woodland species identified as declining in this region. Although clearly not as important as remnant woodland, farm windbreaks, shelterbelts and woodlots of suitable size and composition appear to contribute significantly to avian diversity in agricultural areas and their planting should be encouraged and supported by the rural community and government.

Effects of Rabbit and Kangaroo Grazing on Two Semi-Arid Grassland Communities in Central-Western New South Wales

1989 ◽  
Vol 37 (5) ◽  
pp. 375 ◽  
Author(s):  
JH Leigh ◽  
DH Wood ◽  
MD Holgate ◽  
A Slee ◽  
MG Stanger
Keyword(s):  
Species Composition ◽  
New South ◽  
New South Wales ◽  
Grazing Intensity ◽  
Grazing Pressure ◽  
Present Species ◽  
Grass Species ◽  
South Wales ◽  
Native Grassland ◽  
Wide Range

The effects of rabbits and kangaroos, and rabbits alone, on the biomass and species composition of a native grassland dominated by Stipa nitida/nodosa, Danthonia caespitosa and Aristida contorta, and a grassland dominated by the exotic species Hordeum glaucum, Vulpia spp., Medicago laciniata and the native Erodium crinitum growing at Yathong Nature Reserve in central New South Wales was monitored between 1979 and 1985. Rabbits generally favoured the grassy component; kangaroos also favoured grasses but less so. Changes in non-grass species composition due to grazing was generally insignificant. Changes in species composition due to seasonal differences in rainfall was highly significant. No new species appeared on plots exclosed from grazing for 10 years, suggesting that the grazing by livestock, rabbits, and kangaroos in the past has determined the present species composition. The annual biomass consumption by rabbits averaged over 6 years was 100-200 kg ha-1, which is equivalent to reducing the carrying capacity by one sheep for every 2-4 ha rabbit-infested area. In the native grassland the spatial pattern of rabbit grazing, as indicated by faecal pellet distribution, biomass removal, and percentage of 'unpalatable' species in the pasture, shows greatest grazing pressure to be within 50 m of the warren, grazing intensity dropping off from there to 300 m the greatest distance studied. From the start of the study 'palatable' species, especially grasses, were at their lowest density within 50 m of the warren; this appeared to be a historical effect of grazing. No patterns were discernible in the pasture dominated by introduced species. Little change in species composition of these grasslands can be expected under a wide range of grazing pressure, except close to rabbit warrens.

By-catch from Praen trawling in the Hawkesbury River, New South Wales: Species Composition, distribution and Abundance

1990 ◽  
Vol 41 (1) ◽  
pp. 13 ◽  
Author(s):  
CA Gray ◽  
VC McDonall ◽  
DD Reid
Keyword(s):  
Species Composition ◽  
New South ◽  
New South Wales ◽  
Spatial And Temporal Variability ◽  
Composition Distribution ◽  
Number Of Species ◽  
South Wales ◽  
By Catch ◽  
Autumn And Winter ◽  
Number Of Individuals

This study examined spatial and temporal variability in the composition, distribution and relative abundance of by-catch from prawn trawl sampling in the Hawkesbury River, New South Wales. It also determined whether there were differences in the fauna between sections of the river that are open and closed to prawn trawling. By-catch was sampled monthly between March 1986 and February 1988 in three areas along the river that differed in distance from the mouth of the estuary and in salinity. The total incidental catch comprised 75 species of fish, 13 species of crustaceans and 5 species of molluscs: 42 species were commercially and/or recreationally important. Classification and ordination analyses showed that the species composition of the by-catch differed between the area closest to the mouth of the estuary and that furthest upstream, and that this difference was relatively consistent throughout time. The number of species in the by-catch decreased with increasing distance upstream. Annual and seasonal changes in the number of species were similar in all areas along the river: more species were caught in 1987 than in 1986, and in autumn and winter each year. In contrast, the number of individuals caught differed among areas and these differences varied between years. Similarly, seasonal fluctuations in the numbers of individuals caught varied between years, but these variations were similar in all areas. In the area furthest upstream there were no apparent differences in the numbers of species and individuals caught by prawn trawl sampling in sections of the river open or closed to prawn trawling.

Hunter Activity and Waterfowls Havests in New South Wales, 1977-82

1985 ◽  
Vol 12 (3) ◽  
pp. 515 ◽  
Author(s):  
SV Briggs ◽  
MT Maher ◽  
CC Davey
Keyword(s):  
Species Composition ◽  
Annual Variation ◽  
New South ◽  
New South Wales ◽  
Composition Effect ◽  
Regional Bias ◽  
South Wales ◽  
Black Duck

The results of six annual surveys of waterfowl hunters in New South Wales by mail card are reported. The aims of the survey were to ascertain reported distribution of hunting effort, size and composition of hunters' bags, and state of hunter origin. Hunting effort and waterfowl harvests were highest in southern inland New South Wales. Seasonal bag sizes varied between 15.8 and 27.2 ducks per hunter. Pacific black duck, grey teal and maned duck made up 88.6% of hunters' bags. About half the hunters in New South Wales originated from Victoria. Bag size and species composition, effect of reducing bag size on total harvest, regional bias in hunting effort and harvest, and annual variation in licence sales are discussed.

Biological observations on sharks caught by sport fisherman of New South Wales

1984 ◽  
Vol 35 (5) ◽  
pp. 573 ◽  
Author(s):  
JD Stevens
Keyword(s):  
Sex Ratio ◽  
Species Composition ◽  
New South ◽  
New South Wales ◽  
Prionace Glauca ◽  
Sphyrna Lewini ◽  
Isurus Oxyrinchus ◽  
South Wales ◽  
Gravid Females ◽  
Breeding Seasons

Between 1979 and 1982, 523 sharks representing four families and 13 species were examined from sport fishing catches off New South Wales. Additional catch data were available from records of the Sydney Game Fishing Club extending from 1953 to 1979. The species composition of sharks caught changes through the year, probably as a result of seasonal variations in water temperature. Prionace glauca and Isurus oxyrinchus are most abundant in the catches during the cooler months from May to November. Galeocerdo cuvieri, Carcharhinus brevipinna, C. longimanus, C. falciformis, C. limbatus and Sphyrna lewini are taken principally during the warmer months from December to April. The sex ratio of P. glauca and Sphyrna zygaena changes through the year due to a seasonal influx of gravid females. At least six of the species examined give birth off New South Wales and, apart from C. falciformis, all of these appear to have restricted breeding seasons. P. glauca and S. zygaena feed mainly on cephalopods and to a lesser extent on fish, I. Oxyrinchus principally on fish, and G. cuvieri mostly on fish, birds, unidentified mammals and cephalopods.

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