Ix 



Thirty- second Afinual Report 



has been generally accepted. Variations in the physical conditions 

 of the water, or in the quantity or kind of the minute floating organisms 

 on which the herring mainly subsists, are believed by many to be the 

 main cause, and since 1904 periodical observations have been carried 

 on in Lochfyne with the object of ascertaining whether this is the 

 correct explanation. At a number of places in the loch a series of 

 temperatm'e observations are made at different levels, and collections 

 of the floating food secured, and it is proposed to continue these invest- 

 gations imtil the herrings return to the loch in their former abundance, 

 so that comparison may be instituted between the observations taken 

 in the period of scarcity and those taken in the period of abundance. 



As stated above, these investigations were carried on last year as far 

 as possible with the means at disposal. As the fishery cruiser stationed 

 in the district cannot be made available for the observations, the practice 

 has been to hire a small yacht when that can be done (in the summer 

 months), but in winter when yachts are laid up the observations can 

 only be made by means of a fishing-boat, and there are objections to the 

 use of such a craft in w^inter by the scientific staff. Under these circum- 

 stances the Board approached the Development Commissioners with the 

 view of obtaining a grant for the provision and maintenance of a motor 

 boat suitable for the work, and the application has been favourably 

 entertained. 



The Natural History ol^" the Lobster. 



As stated in last Annual Report, the Board have had under con- 

 sideration the question of what might be done to promote the lobster 

 fishery and to increase our knowledge of the life-history of the lobster, 

 and of the conditions under which lobster culture might be initiated 

 with advantage. Attention was directed to the lobster pond at Culli- 

 pool, Luing, near Oban, which belongs to the West Highland Lobster 

 Company, and in which from 15,000 to 20,000 lobsters can be accom- 

 modated. The manager kindly granted facilities for observations 

 and investigations to be made in connection with the lobsters at 

 the pond, and Dr. H. C. Williamson visited Luing for the purpose 

 in July and October. Attempts were made to discover the lobster 

 fry of the year, but without success, and their whereabouts is unknown. 

 A number of small lobsters, under eight inches in length, were taken 

 atGarvelloch by the use of a small-meshed covering on the lobster-creels, 

 about sixty being secured in two months. With regard to the migration 

 of the lobster, very few of those which were labelled were recaptured, 

 and they were invariably retaken within a distance of not more than a 

 quarter of a mile of the place where they were liberated. Two of the 

 lobsters were recaptured twice. The observations on the change of 

 weight of the lobsters while confin'ed in the pond were continued. 

 Fourteen, ten males and four females, were weighed after having been 

 in the pond for from four to five months, and it was found that the 

 weight of four had remained unchanged, two had decreased in weight, 

 and eight had increased by from one quarter of an ounce to two ounces. 

 The difference was thus comparatively small. Experiments were 

 also made with different models of creels. It was found that an 

 ordinary creel covered with small meshed netting fished better than 

 the usual creel. 



