110 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



Samples of the fish were bought from time to time from the 

 men for investigation, and on one occasion a personal visit 

 was made to the area in the police cutter " Piel Castle." 



Size and Weight of the Fish. 



The size of the fish caught varied from 21 cms. to 36 cms. 

 in length, measured from the tip of the snout to the base of 

 the fork of the tail. Mackerel between 22 cms. and 26 cms. 

 were abundant, but the larger sizes appeared to be 

 comparatively scarce. The scarcity of the larger sizes may 

 have been due to their absence in the area usually fished by 

 the local men. It was quite noticeable during the visit to the 

 fishing ground that boats, fishing off the south end of Walney, 

 were catching large numbers of the smaller sizes. The fish 

 caught off the North end of Walney Island and at the entrance 

 to Duddon Channel were nearly all over 28 cms. in length. 

 The local fishermen rarely went so far North, for if the wind 

 happened to die away — a not infrequent occurrence, they 

 would then have been outside the tidal drift into Barrow 

 Channel. The mackerel caught in Barrow Channel and in 

 the stake nets at Roosebeck were usually all over 30 cms. 

 The weight of the fish increased very rapidly per centimetre, 

 as will be seen from the table. The average weight of a 21 cms. 

 mackerel was found to be 94 grammes. A 36 cms. mackerel 

 weighed 484 grammes. This represents an increase in weight 

 of 390 grammes for an increase in length of 15 cms. Fish of 

 the same length varied considerably in weight according to 

 the condition of the stomach. An empty fish of course weighed 

 less than one which had been recently feeding. Two fish 

 measuring 31 cms. weighed 290 grammes and 330 grammes 

 respectively. The former had nothing in its stomach while the 

 latter contained two freshly captured sand eels measuring 

 12 cms. in length. 



