Year: 1937
Type: article
Abstract: THE accompanying paper embodies the results of the investigation into the food of trout in New South Wales carried out during the season 1935-1936, and gives details of the stomach contents of 108 Rainbow Trout (Salmo irideus Gibbons) and 72 Brown Trout (Salmo tario Linnams).The information obtained in the course of the season's work forms a valuable addition to our knowledge of the varied forms of life which constitute the diet of the fish in those inland waters from which it was possible to obtain material for examination.Members of the Rod Fishers' Society of New South Wales again ably assisted in securing and submitting stomachs from the fish caught, and by their encouragement and co-operation have rendered the investigation possible.It is, however, somewhat disappointing that so few streams are represented, in spite of repeated requests for material from new localities, especially as the information which could have been obtained from such sources would have been of undoubted value in estimating the relative suitability of these waters for future liberation of fry.The information which has been obtained, however, has served to widen considerably our knowledge of certain rivers, and has, in some cases, filled lacunre in our records, rendering possible the compilation of very complete data for some districts.It is owing to the enthusiasm of Dr. A. J. Spiller Brandon that our information regarding the Tuross River, with reference to both Brown and Rainbow Trout, is very satisfactory, and forms a valuable basis for further work, especially should it be considered necessary to make a detailed survey of the aquatic and terrestrial life of the stream.Such a survey, carried out in full detail on one river, would prove of undoubted scientific interest and value.Owing to the kindness of Dr. A. J. Spiller Brandon, I was enabled to accompany him to the Tuross River in January, where, as his guest, I was able to carry out work in the field, which, in spite of the short time available, has been valuable in elucidating certain problems that had developed in the course of the laboratory work to which the investigation had previously been confined.This field work will be referred to in greater detail below, together with certain tentative recommendations arising from my observations. Notes on Food.The presence of fish fry in four stomachs of Rainbow Trout from the McLaughlin River is of considerable interest in connection with the contention of many anglers that the adult fish are responsible for the destruction of many trout fry.Seventy-seven fry were obtained, all in an advanced state of digestion, Barrington River.Mr. G. H. Montgomery spent a week or two on the Barrington River.The weather was not good, and on the whole his trip was not successful.Dr. C. Anderson reported the fishing as generally unsatisfactory.This river is a small stream with some big holes here and there. Gungarlin River.Mr. R. J. Jenner visited the Gungarlin River on two occasions during the season.This stream has its source between Kiandra and Adaminaby, about 6,000 feet above sea-level, and winds downwards through the Snowy Plains to the Snowy River.In December the fish were numerous, and one could say that this stream is the breeding ground for the Snowy and other rivers connected with it.The fish averaged two pounds. Fish River.Mr. W.' J. Forbes visited Oberon at the beginning of the season, but weather conditions were unsatisfactory and the fish were not moving.Mr. Wm.Smith was at Oberon in October, but only caught a few fish.He was there again for Christmas, when the river was very low and clear, and the fish could be seen moving about, but results were not satisfactory. Duckmaloi River.At the opening of the season, Mr. Maurice Brown visited "Trout Park" on the Duckmaloi River, where he found that the fishing was not good, and he only caught enough for the camp.He went there again during the season, with the same result. Tuross River.Dr. A. J. Spiller Brandon reported that his experiences of the past season were varied, and that reports which had come to hand, not only from this State but Victoria, were to the effect that the season just closed was below the usual standard.He said it was very hard to explain this.Conjecture only is possible, but we know that it has been a very extraordinary season, with cold weather and high winds, interspersed with hot days; and nothing seems to upset trout more than sudden changes.Particularly dry weather was experienced, and possibly this had a quietening effect on the fish in regard to their feeding habits, and may have also affected the various insects, etc., on which the trout live.During the first week in October, Dr. Brandon visited the Tuross River mainly for the purpose of releasing the fry which had hatched in the Society's Hatching Box in the river.He was there for 24 hours, and after attending to the box, E No. 51.-<;', ?weight; 11 NoveIliber, 1935, 2.20 p.m. Collected by Mr. Jas.Gaden.Amphibia: Remains of a frog.No. 52.-<;', ?weight; 11 November, 1935, 3.30 p.m. Collected by Mr. Jas.Gaden.Coleoptera: 2 small Dytiscid beetles (Necterosoma penicillata).
Source: Records of the Australian Museum
Author: Keith C. McKeown
Institution: Australian Museum
Language: English
Subfield: Nature and Landscape Conservation
Field: Environmental Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2917952016