of the Fishery Board for Scotland. 



Ivii 



Board, on the same general lines as in previous years. Most of the 

 research work has been conducted at the Marine Laboratory at the 

 Bay of Nigg, Aberdeen, and other inquiries in relation to the herring 

 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, and St. Combs, and the fry 

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

 fishermen at various places on the coast have shown interest in the fish 

 hatching work, which they believe has helped to improve the plaice 

 fishing in their neighbourhood. During the last twelve years a total of 

 over 226,000,000 of the fry of the plaice have been liberated along the 

 coast of Aberdeenshire. 



THE HATCHING OPERATIONS. 



In the course of 1912 several consignments of live plaice were 

 brought to the Hatchery from the " Goldseeker " and placed in the 

 spawning pond, most of the fish having been caught in the Moray Firth. 

 The last consignment was put into the pond on December 27th. As 

 is always the case, a proportion of the fish died subsequently, mostly 

 from injuries received in the process of capture, and the stock at the 

 commencement of the hatching season was not so large as it generally is. 

 As explained in former Reports, 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 10th 

 February, and the last on May 8th, a period of 87 days, as compared 

 with a period of 109 days in 1912, when the stock of fish was larger. 

 The temperature of the water in the spawning pond during the season 

 varied from 3 degrees C. in January to 7 '6 degrees C. in May. 



The estimated number of eggs collected from the spawning-pond 



