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late phase. Before this takes place both the spleen and the kidneys appear to have undergone complete necrosis and to be without function.

When it became possible to obtain specimens sufficiently fresh for bacteriological examination, Professor Mackie of Edinburgh University very kindly undertook to make the necessary tests, and Miss Williamson, one of his qualified research workers, commenced a series of cultures. The organisms developed were found to be most virulent, and small fishes infected died in from seven to fourteen days and before the disease had developed to any great extent. The organism was definitely diagnosed as Baccillus salmonicida, and was found in all organs, in the blood, and in the muscular lesions. In connection with the fact already related that fish came in from the sea in an advanced stage of the disease, a number of tests were made as to the effects of different waters. Great variation was observed in both fresh and sea water, but apparently the bacillus survived the shortest time in tap water.

Similar results to those obtained by Dr. Arkwright as to temperature and as to growth in tissual extracts were obtained, but the statement that sea water kills the bacillus, made by Dr. Arkwright and accepted by Mr. Pentelow and others, was not borne out.

The problem of how it may be possible to combat this disease is likely to be very complicated and to require the close observation of a bacteriologist in some locality where the trouble has arisen and where fresh material can be obtained so long as the appearance of the disease continues.

It seems to have been taken for granted by some that there has been a gradual spread of the disease, and that direct infection of some kind has been present. This does not appear to me to be by any means the case. The Lledr outbreak, for instance, began at the close of the war, and has continued irrespective of any similar outbreak within a wide radius. Similarly the four outbreaks in Scotland in the summer of 1926, in the Grimersta, the Lyon, the Doon, and the Solway Dee, were so widely separated that it is impossible to view the occurrences as having some direct connection. One must look rather, I think, for conditions common to all four places, conditions favourable for the growth of the bacillus.

It appears to have been ascertained in both the Lledr and the Exe that the disease is worst in wet years. As a rule it appears in summer, and synchronises with the warm period of the year. Affected fish which have been taken as late as October appear to have been found considerable distances below the places where the disease was rampant, and the inference is, I think, that they were infected fish which had dropped down the river, and which had been able to resist the attack of the disease longer than the fish which remained in the most seriously infected area. No doubt a high water temperature may cause fish to be less resistant, but it is clear from the cultures made under different thermal conditions that while the bacillus cannot exist at a high temperature, such as that for instance of the human subject, it exists and multiplies much faster at a temperature of 65° to 68° F. than at any other. The temperature factor, therefore, should not be overlooked in conjunction with the more vital factor which may have still to be found.

There is one very significant feature which Mr. Hall in his

Lledr experiences has emphasised, viz. the probable connection between old cesspools and the disease. In wet seasons, when the Lledr disease is worst, a cesspool for a village just above where all the disease occurs is commonly discharging freely into the river. Similarly, in the case of the Exe, it appears that sewage of Exeter, which is spread on land, is freely washed into the river in wet seasons. In Scotland isolated houses very commonly adopt the cesspool system, and while it may be the case that cesspools exist in all the places visited by the disease, they also exist in a great many places as yet unvisited by the disease. But the bacteriological condition of old and uncleaned out cesspools might repay examination. The Lledr cesspool is being removed and a more hygienic arrangement installed under the supervision of the Ministry of Health.

LEGAL DECISION ON OBSERVANCE OF WEEKLY CLOSE TIME.

A case of very considerable importance, involving the principle upon which the observance of the weekly close time should be based in practice, has been decided by the High Court of Justiciary.

In September 1926 the case was heard in the first instance by the Sheriff-Substitute of Aberdeen.

The Fishery District Board for the Aberdeenshire Dee, at the instance of their clerk, Mr. R. P. Stott, Advocate, Aberdeen, complained against the Aberdeen Harbour Commissioners, in that during certain periods which were weekly close times

they did by means of bag nets which they caused to be set in the Dee, and in the sea, fished for and took, or did aid or assist in fishing for and taking, or, alternatively, did aid or assist in taking 165 salmon during eleven periods of the weekly close time from April 10th to July 5th."

Section 15 (2) of the Salmon Fisheries (Scotland) Act, 1868, enacts that:

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Every person who fishes for, takes, or attempts to take, or aids or assists in fishing for, taking, or attempting to take, salmon (except during Saturday or Monday by rod and line) during the weekly close time, or contravenes in any way any byelaw in force regarding the observance thereof, shall for every such offence be liable to a penalty not exceeding five pounds, and to a further penalty not exceeding two pounds for every salmon taken or killed in an illegal manner, and shall forfeit the salmon so taken; and all penalties imposed under this Act and the recited Acts, or any of them, shall be in addition to the costs and expenses of prosecution and conviction."

The points of the case were these:

The Commissioners appointed under the Salmon Fisheries (Scotland) Act, 1862, defined the limits of the estuary of the River Dee with relation to two structures then existing, viz.: (1) the North Pier, and (2) the South Breakwater at the entrance of Aberdeen Harbour.

At a later date the Aberdeen Harbour Commissioners, under statutory powers, made material alterations on the harbour works, including (1) the extension of the North Pier eastwards or seawards

for a distance of 166 yards; (2) the partial demolition of the then existing South Breakwater; and (3) the erection of a new South Breakwater 420 yards or thereby eastwards from the site of the old South Breakwater.

The new South Breakwater is situated outwith the limits of the estuary as laid down by the Administrative Commissioners, and the complaint had reference to the capture of salmon during the weekly close time, and by means of three bag nets set close to this breakwater.

The bag nets had leaders 35 to 40 fathoms long, and the leaders were removed during the weekly close time, as required by Byelaw D (3) of the Salmon Fisheries (Scotland) Act, 1868. Further, nets had been fished in the position of those bag nets for 60 years.

The Dee Fishery District Board had found, however, that salmon swam into the nets during the weekly close time, owing, in all probability, to the proximity of the nets to the breakwater, and complaint was made accordingly that the weekly close time was not being observed, although the byelaw as regards the removal of leaders had been complied with.

The defence, apart from certain preliminary points, was that the Regulations set forth in Schedule D (3) of the Salmon Fisheries (Scotland) Act, 1868-the Byelaw requiring the removal of leaders-constitute a complete code for the conduct. of bag net fishermen, so far as concerns the observance of the weekly close time; and that accordingly the prohibition contained in Section 15 (2) quoted above-does not and cannot apply to bag net fishermen who have obeyed the injunctions laid down for the observance of the weekly close time.

The Sheriff-Substitute held that the 165 salmon had been captured by the defendants during the weekly close time and had been appropriated by them in contravention of the statutes, and that the removal of the leaders did not satisfy the Acts, in that Section 15 (2) required that salmon be not fished for or taken during the weekly close time.

The case was appealed, and was heard in the Justiciary Court, Edinburgh, in March 1927 before the Lord Justice-General and Lords Sands and Blackburn.

As a result the decision of Sheriff-Substitute Dallas, Aberdeen, was upheld.

The Opinions of the Judges are of special interest as bearing directly upon the proper interpretation of the clauses of the Acts. dealing with the observance of the weekly close time, irrespective of due compliance with a byelaw designed to assist the observance of the law.

All bag net fishers are aware that it is possible, with very little trouble, to throw out of fishing order the head of any bag net by releasing the head stake and allowing the head to collapse, and that this is not infrequently done when great masses of jelly-fish float into and choke the nets.

If a bag net is so situated that salmon are liable to swim into it when the leader is off, a similar precaution should be taken to prevent an infringement of the law.

W. L. CALDERWOOD,

Inspector of Salmon Fisheries of Scotland.

NUMBER of PACKAGES and average PRICE per lb. of SALMON delivered at Billingsgate

Market during the year 1926.

(Received through the courtesy of The Fishmongers' Co., London.)

11111111

Month.

January

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Totals

8,630

9,885

8,802

58 1,538 70

114

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REPORT OF ASSISTANT INSPECTOR OF SALMON

FISHERIES.

As in the past few years, research during 1926 has been divided between a general investigation of sea trout and a more particular investigation of certain aspects of the life history of salmon; both these lines of work have been carried out in continuation of programmes started in previous years.

I. SALMON.

(a) Scale Investigations.

The chief preoccupation has again been the collections of scales and measurements of salmon made in the rivers Spey and Dee, and work was done on the 1923 and 1924 samples. The 1923 material has been completed and the results published, and the figures for the 1924 catch are in course of arrangement, with accompanying text, for press.

When collections over a sufficient number of years have been examined it is the intention to review fully the return in adult fish resulting from a particular year's stock of eggs; these adult fish range in size from the early grilse of 2 or 3 lbs. to those of more than 40 lbs. that have spent over four, or perhaps five, years in the sea. Three years' results have been published, and from these it has been found possible to deduce certain conclusions regarding more especially the manner of growth and the relationship between the length attained in one year and that made in the succeeding year or years, as well as the connection between the growth of the fish in the first year of sea life and the total time spent in the sea. Conclusions on the relative state of fatness of fish of different sizes and various age groups were also obtained. The results on these points have been summarised and published as a contribution towards a more complete knowledge of the life and development of the salmon.

A collection of scales and measurements of salmon caught in the Grimersta, Lewis, made in 1925, was also examined, and the data obtained have been reported upon and published. Like many, one might say most, west coast rivers, the Grimersta is essentially a grilse district, although some few spring fish may be found in February and a rather larger number in March. The fish feeding resources of the streams and lochs are small, and it is therefore not surprising that an unusually high proportion (61 per cent.) of the smolts do not migrate until three years of age, but it is rather remarkable that, in a district with no coast nets of any importance and where no other netting has been exercised for a very long time, the proportion of fish which survive to return to spawn for a second time is no higher than in the most heavily netted districts of the mainland.

Doubt has been expressed on occasions by certain investigators as to the accuracy of the first year parr lengths calculated from scale measurements on the ground that they appear, in many instances, to be unduly small; it has been suggested that either the "straight" calculations from the scale measurement require correction by a constant or that an error was made in accepting the small innermost portion of the scale as representing a year's

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