SEA FISHERIES LABORATORY. 131 



very few of them exceeding 9 or 11 inches in length, and 

 as the ground is frequently trawled over both with shrimp 

 and ordinary trawls, the destruction of small fish is very 

 great. After the middle of December the fish begin to 

 leave this part of the Mersey and come down to the banks 

 off Crosby and Formby. These banks are then in their 

 turn continually trawled over, so that the destruction goes 

 on for a large part of the year. If it is not possible to 

 apply to this part of the district the same thorough 

 measure which has been applied to Blackpool, and entirely 

 prohibit trawling in any form, a close time, which would 

 take effect when the greatest number of fish are present 

 on the respective areas, would be very useful, such as 

 that the upper parts of the Mersey be closed against 

 trawling from the beginning of October till the end of 

 December, and that the lower parts be closed from 

 January till some time in summer. There seems to 

 be especially heavy destruction in July, August, and 

 September around Burbo Bank and near the deposit 

 ground. The experiment might be tried for a couple of 

 years to ascertain what amount of beneficial effect would 

 result from a partial closure, statistics being collected 

 weekly or monthly. So long as no artificial hatching is 

 done in the district, it is only by a most careful protection 

 of the natural rearing grounds of the young fish that the 

 quality and quantity of the larger fish on the various 

 fishing grounds around our coasts can be maintained. 

 As to the necessity of supplementing these restrictive 

 measures by hatching, and so adding to the supplies in 

 the sea, that is discussed elsewhere (see p. 136). 



In the following list we give the average number of 

 fish caught on the Blackpool closed ground during the 

 year, and for the sake of comparison we also give the 

 figures for the previous year from the last Eeport : — 



