22 



Fishery Board for Scotland. 



9. The eggs in the later stages of development are relatively most 

 numerous in the deeper water layers. 



(c) Stations along the South Shore of the Moray Firth. 



Observations were made at a series of stations along the south 

 shore of the Moray Firth from Nairn Bay to Kinnaird Head. The 

 stations taken in order from west to east are : — Nairn Bay, Burghead, 

 Lossiemouth, Trawling Station X. Moray Firth, Portknockie, Troup 

 Head, and Kinnaird Head. All these were visited in March 1906, 

 and a direct comparison can be made between the frequencies in the 

 different surface hauls. 



The greatest frequency both in the number of eggs at the " a " stage 

 (1294) and in the total number (2450) was found at Lossiemouth. It 

 has been stated already that these frequencies are the second highest 

 from any station on the Scottish Coast. There is a gradual fall in the 

 frequencies of the eggs in the sm-f ace hauls from Lossiemouth eastwards 

 towards Kinnaird Head, and there is a marked fall westwards at 

 Burghead Bay. The conclusion based on this evidence is that plaice 

 were spawning in numbers at Lossiemouth in March, and that the 

 number of spawning plaice was less both in an easterly and westerly 

 direction from that locality. This fall in the absolute density of the 

 eggs in the " a " stage is correlated with a fall in their abundance relative 

 to total number of plaice eggs obtained in the locality. The following 

 table gives the total number of eggs taken at different depths and the 

 percentage of these in the " a " stage : — 



Haul. 

 Vertical 

 Surface 

 5 Metres 

 10 Metres 

 Midwater 

 Bottom 



Burghead. Lossiemouth. St. X.M.F. Portknockie. Troup Hd. Kinnaird. 



14 



20 

 206 

 292 

 .356 



18 



17 



2450 



360 



456 

 232 



202 



Percentage at 

 " a " stage . 



.32-8 



51- 



51-9 



28-6 



18-3 



•9 



The extreme limit is reached in the Kinnaird Deep, where the per- 

 centage of plaice eggs in the " a " stage is less than one. On the other 

 hand, more than half the number of eggs taken at Lossiemouth and 

 Station X., Moray Firth, were newly spawned. (Fig. 5.) 



