24 



Part III. — Seventeenth Annual Report 



waters. The results of these various hauls will be found in the Tables 

 appended to this Report. 



Comparison of the results obtained in the various years in which 

 trawling investigations were made in the Firth of Clyde shows that, 

 taking all the stations together and all kinds of fish, the average number 

 per haul of the net has generally increased over the period comprised, 

 although considerable fluctuations occurred in different years. In 1888 

 the general average for the closed area was 109*7 per haul ; in 1890 it 

 was 99'5 per haul ; in 1895 it was 113-4 ; in 1896 it was 120-7; in 

 1897, 112-5, and last year the average rose to 189'3 per haul. The 

 averages for the two groups of flat-fishes and round-fishes show that the 

 rise in flat-fishes has been fairly steady. The averages are as follows : — 





1888. 



1890. 



1895. 



1896. 



1897. 



1898. 



Flat-Fishes, 



61-2 



61 I 



64-7 



75-5 



84-8 



94-7 



Round-Fishes, 



44-7 



351 



43-6 



35-1 



27-8 



49-9 



An examination of the statistics relating to the different kinds of 

 flat-fishes captured shows that the increase of flat-fishes over the period 

 has been due to an increase in witches and long rough dabs ; the aver- 

 ages for plaice and lemon soles, neither of which are abundant in the 

 area, have, on the whole, somewhat diminished. The figures are as 

 follow : — 





1888. 



1890. 



1895. 



1896. 



1897. 



1898. 



Plaice, - 

 Lemon Soles, 

 Witches, 

 Common Dabs, 

 Long Rough Dabs, 



5-3 

 7-4 

 12-7 

 23-8 

 5-3 



3-4 

 5-6 

 19-7 

 13-8 

 17-7 



2-3 

 2-8 

 25-7 

 14-0 

 20-0 



2-1 



7-2 

 35-9 

 15-7 

 15-1 



2-5 

 5-3 

 47-1 

 12-7 

 16-8 



3- 0 



4- 1 



36- 5 

 13-6 



37- 3 



But, as stated in previous Reports, inferences as to changes in the 

 abundance or relative proportions of the fishes in the closed area of the 

 Clyde must be provisional, inasmuch as the observations comprise only 

 ten series of hauls at the various stations. It will require much more 

 extended observations both in the Firth of Clyde and in the Moray Firth 

 before conclusions can be drawn with any degree of certainty as to the 

 results of the closure. In the Firth of Forth and St. Andrews Bay it 

 was found, after ten years' investigation, that the most important change 

 that occurred in the relative abundance of the food fishes in the closed waters 

 was a diminution of the more valuable flat-fishes, plaice and lemon soles, 

 which spawn offshore and not in the closed waters, and an increase in 

 the comparatively worthless dabs, which spawn copiously in the closed 



