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Thirty-Hrst Animal Report 



and the herring fishery have been made in Lochfyne, in continuation 

 of the observations of preceding years, and also in the Moray Firth 

 with reference to the closing of the waters there to the operations of 

 trawlers. The special statistics of the catches of the line-boats in the 

 Moray Firth have been collected monthly through the Fishery Officers 

 as before, and the old trawling stations of the s.s. " Garland " have been 

 periodically examined with a beam trawl by the s.s. " Goldseeker," as 

 frequently as circumstances allowed, and at dates corresponding as far 

 as possible with those of former examinations, both with the beam- 

 trawl and with the otter-trawl. A report on these investigations and 

 on the statistics is in course of preparation. 



The fish-cultural work at the Hatchery at the Bay of Nigg was con- 

 tinued in the Spring last year throughout the spawning season of the 

 plaice, and is described below. A number of requests for plaice fry 

 were received on behalf of the fishermen at various parts of the coast, 

 and these were as far as possible complied with, consignments being 

 forwarded to Peterhead, Fraserburgh, Sandhaven, and Kosehearty, and 

 the fry liberated off the coast in the neighbourhood of these localities. 

 The fishermen at various places along the coast of Aberdeenshire have 

 reported an improvement in the plaice fishery, which they attribute 

 to the liberation of many millions of fry during the last eleven years, 

 the total in the period aggregating nearly 220,000,000. 



The Hatching Operations. 



In the course of the year several consignments of live plaice, which 

 had been caught in the Moray Firth, were brought to the Hatchery 

 by the research steamer Goldseeker," and about 800 plaice of both 

 sexes were contained in the spawning-pond when the season began, 

 Not a few of these were, however, small in size, and some of them did 

 not reach maturity. As explained in former Eeports, the adult 

 plaice of both sexes are retained in a large tidal pond, into the water 

 of which the eggs are shed, and where they are naturally fertilised 

 during the spawning season. The floating eggs are collected at 

 intervals by means of a fine net and transferred to the Dannevig 

 hatching apparatus, hatching taking place in between three or four 

 weeks, as a rule, in the early part of the season, in January and 

 February, and about a week sooner in the latter part of the season, in 

 April and May. The period, however, varies with the temperature. 

 The larval fishes are retained in the apparatus until the yolk-sac is 

 nearly absorbed, when they are transferred to the sea at suitable 

 localities. The first collection of eggs was made on January 26, and 

 the last on May 15, the greater number being obtained, as usual, in 

 March and April. Last year, owing to severe frosts in February 

 and the low temperature of the water in the spawning-pond, the 

 maximum spawning was delayed until the early part of Apri], and a 

 greater number of eggs were collected in that month than in March. 



The estimated number of eggs taken from the pond during the 

 season was 21,650,000, which was a considerable increase compared 

 with the previous season, but less than in many former years. The 

 loss in the process of hatching in the apparatus amounted to about 22 

 per cent., and the estimated number of fry obtained and liberated in 

 the sea was 19,250,000. In the earlier part of the season the water 



