The Salmon n 



netting during the autumn and winter. About fourteen months after 

 the smolts have migrated, a run of small grilse appears. The first 

 usually arrive during the last week of May or the first week in June, 

 and in the Tay weigh from i^- to 2^ Ibs., while in some rivers they are 

 even smaller. Most of the northern rivers are much earlier than the 

 Tay, and grilse make their appearance as early as the first week in 

 April. As the season advances the weight of the grilse increases 

 rapidly. This is due to its food being most plentiful in the summer 

 months. At the end of June they weigh about 5 Ibs., at the end of 

 July 8 Ibs., and at the end of August 10 Ibs. exceptionally large ones 

 weighing from 10 to 12 Ibs. In cold, backward seasons they are much 

 smaller, and this applies to all rivers in Great Britain. The grilse 

 distribute themselves over the whole river, and the run continues until 

 the end of December. In the first week of November spawning 

 commences. Many return to the sea soon after spawning, while 

 others remain until April, and are very greatly reduced in weight, 

 averaging from 2 to 7 Ibs. Their sojourn in the sea varies from three 

 and a half to eighteen months. During this interval a rapid increase 

 in size takes place, and they return again as salmon, double their 

 former weight. They first return about the middle of June (see 

 scales of a grilse after its second return from the sea), and increase in 

 number and weight until the end of December, their age at the latter 

 date being four years and nine months. Others remain in the sea 

 during the winter, and do not return until the next summer, having 

 been away for one and a half years. Thus some spawn in each of two 

 consecutive years, while others only spawn once in that time. Unless 

 one has studied scales, it is difficult to distinguish between a kelt grilse 

 of 4 Ibs. and a kelt of a small spring fish of the same weight. This 

 can easily be done, however, by counting the number of rings on the 

 scales, or the number of contractions on the scales. 



Hitherto it was thought that the small and the large spring 

 salmon were from kelts of grilse of the previous year, but this is not 

 the case. The small spring fish are of the same age as these grilse. 

 They come up in the following spring, and are from 15 to 40 Ibs. in 



