10 



Part III. — Thirteenth Annual Beport 



were collected, the proportion was only 4'4 per cent. The total 

 number in the hatching apparatus was sometimes considerable ; 

 from April 21st to May 13th more than 20,000,000 eggs were 

 undergoing development, and during 13 days above 25,000,000. 

 On such occasions it was necessary to crowd the eggs in the boxes — 

 sometimes to the extent of about 400,000 per cubic foot of water. 



As stated in the Twelfth Annual Report experiments were begun 

 last year with the turbot and sole, the two most valuable species of 

 the marine food-fishes, but no actual spawning took place in the 

 pond, although unfertilised eggs of both forms were obtained, and 

 it was found later that the adults had injured themselves by friction 

 on the wooden flooring. It was, therefore, evident that the system 

 which had succeeded so well with the plaice required modification, 

 and the experiment of substituting a sandy bottom is being tried. 

 It would appear that these fishes transferred from the fishing 

 grounds to the hatchery do not spawn with the same freedom as do 

 the plaice and cod, and require special measures ; the sole in par- 

 ticular seems to be very susceptible of injury. It is noteworthy 

 that the soles confined and thoroughly acclimatised in the tanks of 

 the marine laboratory at Plymouth spawned last season, and all 

 the information and experience available point to the necessity of 

 thoroughly acclimatising these species before they are used as 

 spawners for hatching purposes. 



In regard to the practical results of marine pisciculture in adding 

 to the fish supply, it may be stated that in the United States, New- 

 foundland and Norway — where cod alone has been propagated on a 

 large scale — according to the Official Eeports published in these 

 countries the abundance of young cod has been materially increased. 

 In the neighbourhood of the hatchery on Dildo Island, Newfound- 

 land, the shoals of this fish were so numerous during the past 

 season that they were described as a " solid thick mass covering 

 the bottom for long distances on both sides of the island," and it is 

 stated that fishermen from other parts, on hearing of the abundance 

 of cod, came to Dildo to fish. Sufficient time has not, of course, 

 elapsed since active operations were begun at Dunbar to afford any 

 indication as to the influence of the work in increasing the fish 

 supply, but there are some points of importance that may be con- 

 sidered in connection with the subject. There can be no doubt 

 that the great majority of the fry distributed on the fishing grounds 

 are destroyed from natural causes, but if only a fraction of one per 

 cent, survive, the resulting benefit would far exceed the expenditure 

 upon the work. If one in a hundred of the fry distributed from the 

 hatchery survived, and if the price of the marketable fish be placed 

 at sixpence, the resulting value to the fisheries would be about 

 £18,000. It would require the survival of only one in a thousand, 

 and the marketable fish to be sold at only one penny each, to cover 

 the expenses of the work. 



During the year the hatchery has been visited by, among others, 

 representatives from the Cornwall Sea Fisheries Committee, the 

 North Eastern Sea Fisheries Committee, the Northumberland Sea 

 Fisheries Committee and the Sea Fisheries Committee of Lanca- 

 shire ; also, under the instructions of their Governments, by Dr 

 Roche, the Chief Inspector of the Fisheries of France, Mr Berry, 



