Trout Populations and Habitats in New South Wales

Surveys of most of the trout waters in New South Wales have been made. Relevant data of the trout areas are given in respect to geography, generalized topography, and climate. Chemical and physical conditions of the waters are tabulated. Growth rates of trout and quantitative data on the bottom fauna of some streams have been determined. It is shown that the biological, chemical, and physical characteristics of the trout habitats are related and interdependent to a marked and consistent degree. The waters are separated into three groups on the basis of trout growth. The data suggest that the majority of waters in New South Wales often provide conditions which are limiting for trout. Preliminary population and mortality studies have been made on small sections of nine rivers and on one small lake. The results of a creel census are given. The information from these sources confirms conclusions obtained from the habitat surveys. In addition evidence is presented indicating that certain management procedures should be modified. These include legal length, closed season, and stocking of streams. It is suggested that some of these modifications would have the additional benefit of reducing predation, and that hatchery-reared trout could be utilized on a much wider basis than at the moment for cold-water fish farming.

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A comparison of irrigated maize growth in southern New South Wales on sites with and without a preceding fallow

Australian Journal of Experimental Agriculture ◽

10.1071/ea9830058 ◽

1983 ◽

Vol 23 (120) ◽

pp. 58

Author(s):

WK Mason ◽

WS Meyer ◽

HD Barrs ◽

RCG Smith

Keyword(s):

Soil Water ◽

Root Length Density ◽

New South ◽

New South Wales ◽

Neutron Probe ◽

South Wales ◽

Management Procedures ◽

Initial Hypothesis ◽

Soil Water Extraction ◽

Water Potential Measurements

This experiment was carried out on a grey cracking clay soil near Griffith in southern New South Wales. Maize grown after a two year fallow produced 2.7 t/ha or 45% more grain than maize grown on a continuously cropped site. This difference occurred despite large fertilizer inputs and similar management procedures. The yield differences resulted from increased plant establishment (20%),kernel numbers per cob (26%), and kernel size (11%) in the fallow area. However, experimental results were mostly inconsistent with our initial hypothesis that restricted root growth and soil water uptake were limiting yields on continuously cropped sites. Water use was measured throughout the season with a neutron probe, but no differences in depth or amount of soil water extraction were detected. Root length density and leaf water potential measurements indicated that plant water relations were similar for the two sites and so this did not seem to account for the improved yield from the fallowed site.

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The Effect of Rainfall and Blowfly Larvae on the Toxicity of '1080'-Treated Meat Baits Used in Poisoning Campaigns Against Wild Dogs.

Wildlife Research ◽

10.1071/wr9880473 ◽

1988 ◽

Vol 15 (5) ◽

pp. 473 ◽

Cited By ~ 24

Author(s):

JC Mcilroy ◽

EJ Gifford ◽

SM Carpenter

Keyword(s):

New South ◽

New South Wales ◽

Department Of Agriculture ◽

South Wales ◽

The Moment ◽

Micro Organisms ◽

Wild Dogs ◽

Subsequent Disappearance

Meat baits injected with '1080' poison (sodium monofluoroacetate) according to the method recommended by the Department of Agriculture, New South Wales, Australia, for preparing baits for poisoning compaigns against wild dogs (Canis f. familiaris) and dingoes (C. f. dingo), began to lose their toxicity from the moment of preparation onwards, particularly after different rainfall treatments and when inhabited by calliphorid larvae. The main or most likely reasons for the loss of fluoroacetate were consumption by maggots (mainly larvae of Calliphora augur and C. stygia plus some C. hilli and C. tibialis) and their subsequent disappearance from the baits, leaching by rainfall, defluorination of the fluoroacetate by micro-organisms, and leakage from the baits after injection and during their decomposition. During this study the baits remained toxic to dogs, despite different rainfall treatments, for over 32 days during winter when maggots were absent, and for 6-31 days during summer, when they were present. Under the same conditions the baits contained an LD50 for an average-sized tiger quoll (Dasyurus maculatus) for 4-15 days and 2-4 days, respectively.

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Four recent ciguatera fish poisoning incidents in New South Wales, Australia linked to imported fish

Communicable Diseases Intelligence ◽

10.33321/cdi.2019.43.4 ◽

2019 ◽

Vol 43 ◽

Cited By ~ 7

Author(s):

Alan Edwards ◽

Anthony Zammit ◽

Hazel Farrell

Keyword(s):

Cold Water ◽

New South ◽

New South Wales ◽

Duration Of Symptoms ◽

Lord Howe Island ◽

Ciguatera Fish Poisoning ◽

South Wales ◽

Fish Poisoning ◽

Lizard Island ◽

Seamount Chain

Between 2015 and 2017, the NSW Food Authority investigated 4 ciguatera fish poisoning incidents linked to fish caught in tropical Australian and international waters and imported to New South Wales. Three of the implicated fish were caught near the Capel Bank Seamount, part of the Lord Howe Island Seamount Chain off the coast of Queensland. The fourth incident, in 2017, involved a fish caught between Cooktown and Lizard island, also off the Queensland coast. Thirteen individuals were affected. Early identification of potential Ciguatera fish poisoning (CFP) cases can facilitate a faster incident response, patient diagnosis and treatment. While different fish species were involved, and the severity and duration of symptoms varied between individuals, 3 of the 4 incidents were distinguished by those affected having consumed a fish meal prepared with the head of the fish. Affected individuals also described a sensation of hot/cold temperature reversal or a painful ‘sharpness’ when in contact with or drinking cold water. This paper outlines a series of incidents where a case’s symptoms, which can vary substantially in conjunction with their previous exposure history, the type of fish consumed and how the fish was cooked, can be used to identify potential CFP cases and hence CFP risks that may need to be addressed.

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