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.

Comparison of Bird Counts From Pine Forest and Indigenous Vegetation.

1977 ◽  
Vol 4 (3) ◽  
pp. 281 ◽  
Author(s):  
PV Driscoll
Keyword(s):  
Pinus Radiata ◽  
New South ◽  
New South Wales ◽  
Bird Communities ◽  
Pine Forest ◽  
Native Forest ◽  
Number Of Species ◽  
Eucalyptus Forest ◽  
South Wales ◽  
Forest Habitats

Bird counts were taken in Feb., March and July 1975 in 4 native habitats, ranging from wet sclerophyll Eucalyptus forest to mallee (E. stricta)-heath on the Boyd Plateau, and two Pinus radiata habitats (20 yr and 40 yr) in the Jenolan State Forest, New South Wales, Australia. In each season the number of birds and the number of species was highest in the native forest habitats, lower in the pine habitats and least in the mallee-heath. The composition of native forest, pine forest, and mallee-heath bird communities shows considerable differences.

Variations in sex, length and age compositions of commercial catches of Platycephalus fuscus (Pisces : Platycephalidae) in New South Wales, Australia

2002 ◽  
Vol 53 (7) ◽  
pp. 1091 ◽  
Author(s):  
C. A. Gray ◽  
V. J. Gale ◽  
S. L. Stringfellow ◽  
L. P. Raines
Keyword(s):  
Average Length ◽  
New South ◽  
New South Wales ◽  
Total Mortality ◽  
Mesh Size ◽  
Growth Zone ◽  
Male Fish ◽  
Age Composition ◽  
South Wales ◽  
By Catch

Commercial landings of dusky flathead (Platycephalus fuscus) from four estuaries in New South Wales (NSW), Australia, were sampled for data on sex, length and age composition between February and July each year for 2–3 years between 1995 and 1997. Landings primarily contained female fish, ranging from 55% to 93% by number for different estuaries. Flathead sampled in commercial catches ranged from 30 cm to 96 cm total length (TL), but the majority were 33–50 cm TL. Fish >40 cm TL were primarily female and male fish >45 cm TL were uncommon. The length composition of catches differed between gillnets of different mesh sizes, with the average length of fish being least in the smallest allowed mesh size of 70 mm. Fish were aged by otolith interpretation and the analysis of marginal increments indicated that one opaque and one translucent growth zone was formed each year; the opaque zone being deposited in June–August (winter) and first observed in September–October (spring). Commercial landings included fish aged 2–11+ years, but fish aged 2–4+ years dominated landings in all estuaries. The total mortality of dusky flathead in each estuary was estimated by catch curve analysis and was relatively high, ranging from 0.45 to 1.64. The data indicate that dusky flathead may be heavily exploited in NSW.

Spatial variability in the nekton of a canal estate in southern New South Wales, Australia, and its implications for estuarine management

1995 ◽  
Vol 46 (4) ◽  
pp. 715 ◽  
Author(s):  
MP Lincoln Smith ◽  
PMH Hawes ◽  
FJ Duque-Portugal
Keyword(s):  
Spatial Variability ◽  
New South ◽  
New South Wales ◽  
South Wales ◽  
Estuarine Management ◽  
Main Canal ◽  
Number Of Individuals

The nekton of a canal development in NSW, Australia, is described. Two sites each were sampled from the main canal and in end canals. The main canal had more species of fish than did the end canals, but the number of individuals was similar between locations. Abundance of particular species showed three patterns: species that were more abundant in either location, species that varied between locations and sites, and species that did not differ significantly in abundance. There was little evidence that the nekton from the end canals, which are presumably less well flushed, was depauperate compared with the main canal. Surveys of nekton in canal estates should incorporate spatial variability at two or more scales so that the effects of these human developments can be assessed properly.

The Demography of Feral Pigs (Sus Scrofa) in Kosciusko National Park, New South Wales.

1993 ◽  
Vol 20 (5) ◽  
pp. 559 ◽  
Author(s):  
G Saunders
Keyword(s):  
National Park ◽  
New South ◽  
Seasonal Pattern ◽  
New South Wales ◽  
Protein Food ◽  
Feral Pigs ◽  
South Wales ◽  
Postnatal Mortality ◽  
Alpine Population ◽  
Autumn And Winter

The demography of a sub-alpine population of feral pigs was examined at Kosciusko National Park in south-eastern New South Wales. Reproductive data and age structures indicated a seasonal pattern of breeding, most births occurring in summer and autumn. It is proposed that a decreasing availability of high protein food in the autumn and winter months caused reduced rates of conception. Sows produced 0.84 litters per year with postnatal mortality as high as 85%. The population appeared relatively stable at a density of 1.6 pigs kg-2. Hunting, although illegal in a national park, removed 4.4-15.4% of pigs each year. The overall health and body condition of pigs was good, with no evidence of heavy parasitic burdens or disease. Age-specific body weight and body length in this study were greater than those reported for pigs in semi-arid wester New South Wales.

Diet of red foxes (Vulpes vulpes) in South-west New South Wales, with relevance to lamb predation.

1993 ◽  
Vol 15 (1) ◽  
pp. 39 ◽  
Author(s):  
IW Lugton
Keyword(s):  
Vulpes Vulpes ◽  
Oryctolagus Cuniculus ◽  
New South ◽  
New South Wales ◽  
Ovis Aries ◽  
Red Foxes ◽  
South West ◽  
South Wales ◽  
Preferred Foods ◽  
Autumn And Winter

The diets of 212 foxes (Vulpes vulpes) in the far south-west of New South Wales were determined between 1985 and 1989 and compared with other Australian studies. Mammalian remains, at an overall occurrence of 99.1%, formed the basis of the diet during the autumn and winter months. The most frequently occurring mammals were rabbits (Oryctolagus cuniculus) (34.9%), sheep (Ovis aries) (30.7%) and macropods (Macropus spp.) (20.3%). Insects occurred in 31.1% of stomachs and formed a substantial proportion of the diet. Fresh newborn lamb was identified in only 3.8% of all stomachs, but evidence of lamb consumption was 10 times greater (35.2%) from foxes collected near lambing flocks. Other studies around lambing flocks have also shown a high occurrence of fresh lamb in fox stomachs and there is circumstantial evidence that predation of lambs by foxes can be common. It was concluded that lamb predation is likely to be severe where the fox population density is high, where older foxes predominate, and where alternative preferred foods are scarce. More research is required to confirm these observations.

The impact of trampling on feldmark vegetation in Kosciuszko National Park, New South Wales

2004 ◽  
Vol 52 (3) ◽  
pp. 315 ◽  
Author(s):  
K. L. McDougall ◽  
G. T. Wright
Keyword(s):  
National Park ◽  
New South ◽  
New South Wales ◽  
Species Abundance ◽  
Management Options ◽  
Cushion Plants ◽  
Number Of Species ◽  
South Wales ◽  
Westerly Winds ◽  
The Impact

A popular walking track in Kosciuszko National Park, New South Wales, passes through areas of feldmark vegetation, a windswept community of sparse dwarf shrubs, cushion plants and herbs. The prevailing westerly winds in this area prune the windward edges of the dominant Epacris gunnii shrubs. Layering on the protected side effectively means that the shrubs slowly move across the ridgetops. Twenty-five transects were placed perpendicular to the track in a patch of feldmark north of Mt Kosciuszko. The density of selected species and the total number of species were recorded in quadrats placed in the track centre, track edges and feldmark vegetation at 5 and 10 m from both sides of the track to determine whether the track has interrupted feldmark processes and affected species abundance. The abundance of all species and the number of species per quadrat was lowest in the track centre. Three species (including E. gunnii) were found to be less abundant on the leeward edge of the track than on the windward edge, suggesting that the track has indirectly interfered with feldmark processes. Two of the species were as abundant on track edges as at 5 and 10 m from the track. The area of affected vegetation is currently very small and it may take decades before the effect is obvious to people using the track. Management options for reducing or eliminating the impact are discussed.

Feeding behaviour of the squirrel glider at Bungawalbin Nature Reserve, north-eastern New South Wales

1998 ◽  
Vol 25 (3) ◽  
pp. 243 ◽  
Author(s):  
D. J. Sharpe ◽  
R. L. Goldingay
Keyword(s):  
Feeding Behaviour ◽  
New South ◽  
New South Wales ◽  
North Coast ◽  
The North ◽  
South Wales ◽  
Acacia Gum ◽  
North Eastern ◽  
Squirrel Glider ◽  
Autumn And Winter

The diet of the squirrel glider (Petaurus norfolcensis) was described by qualitative observations of feeding behaviour at a floristically rich site on the north coast of New South Wales. Twelve gliders from six groups were examined over a 10-month period. Flowering and bark-shedding data were also collected. Nectar and pollen were the most important food resources and accounted for 59% of all observations. Banksia integrifolia was the most important source of these foods, but eucalypts were used heavily when in flower and several other genera were also visited. Feeding on arthropods constituted 26% of all feeding observations. Arthropods were harvested in all months of the study from a variety of substrates. Feeding on arthropods was relatively unimportant in May and June when pollen ingestion was presumed to be high. Honeydew was used but was absent from the diet during winter. Acacia gum was obtained from two species in autumn and one, Acacia irrorata, was incised to promote gum production. Corymbia intermedia and Angophora woodsiana were incised for sap in autumn and winter. Sap flows resulting from insect (borer) damage on other species were also used. Fruit, Acacia seeds and arils, and lichens were consumed on a few occasions. The squirrel glider displayed seasonal trends in feeding behaviour that, in part, accorded with observed phenological patterns. The foods used by the squirrel glider during this study were similar to those previously reported for the genus. However, few studies have documented such a diversity of dietary items at one site. Management of the squirrel glider appears to require the maintenance of floristic diversity, and particularly the persistence of midstorey species.

scholarly journals A strategy for developing scientific sampling tools for fishery-independent surveys of estuarine fish in New South Wales, Australia

2007 ◽  
Vol 64 (8) ◽  
pp. 1512-1516 ◽  
Author(s):  
D. Rotherham ◽  
A. J. Underwood ◽  
M. G. Chapman ◽  
C. A. Gray
Keyword(s):  
Large Scale ◽  
New South ◽  
New South Wales ◽  
Cost Benefit ◽  
Independent Study ◽  
Estuarine Fish ◽  
Spatial And Temporal Variability ◽  
Spatial And Temporal Scales ◽  
South Wales ◽  
Cost Efficient

Abstract Rotherham, D., Underwood, A. J., Chapman, M. G., and Gray, C. A. 2007. A strategy for developing scientific sampling tools for fishery-independent surveys of estuarine fish in New South Wales, Australia. – ICES Journal of Marine Science, 64: 1512–1516. The limitations of using fishery-dependent data, i.e. from commercial and recreational fisheries to assess harvested stocks of fish and invertebrates, are well known. Increasingly, fishery-independent surveys are used to validate data from fishery-dependent sources and to provide indices of recruitment and broader ecological information about species not normally retained in fishing operations. Any large-scale, long-term, fishery-independent study must develop sampling gear and designs that are standardized, representative, optimal with respect to the quantity and structure of catch, and replicated over relevant spatial and temporal scales. We present a strategy for achieving appropriate sampling designs. This involves: (i) identifying suitable sampling gears for target species; (ii) testing different configurations of gear and sampling practices to ensure that samples are optimal, representative, and cost efficient; (iii) understanding scales of spatial and temporal variability; and (iv) cost–benefit analyses to optimize replication. Examples of this strategy are illustrated, with brief considerations of the values of pilot research in developing fishery-independent sampling.

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