204 BRITISH FRESH-WATER FISHES 



returning to the river to spawn, for by the act of spawning 

 the fish ceases to be a grilse. 



Some light has been thrown by these observations upon the 

 question whether salmon always return to their native river. 

 The answer, so far as it has been received, is " Generally, but 

 not invariably." Mr. Calderwood gives eighteen instances * 

 of fish recaptured in the same river after the lapse of at least 

 one season, and four in which fish were recaptured in other 

 rivers. Only one of these had travelled to a distant river 

 namely, one taken as an unspawned female in the Spey at 

 Fochabers on December I4th, 1896, marked, returned to the 

 water, and retaken as a kelt on February 22nd following in 

 the Aberdeenshire Dee. The mouths of these two rivers are 

 ninety miles apart. 



Out of sixty-seven instances of fish captured twice within 

 the same river at intervals varying from 35 to 137 days, 

 without having revisited the sea in the interval, in sixty-two 

 cases there was a loss of from 2 Ib. to ^ Ib. in weight, and in 

 five cases only no change in weight was recorded. This bears 

 on the vexed question about salmon feeding in fresh water, 

 and, contrasted with their proved rapid increase in salt water, 

 seems nearly conclusive against their taking nourishment after 

 they have quitted the sea. 



Fish culture has made considerable advance in this country 



during the last half-century, and salmon hatcheries have been 



Artificial erected in various parts of the United Kingdom. 



incubation. j t wou ld be foreign to the purpose of this book to 



enter upon a technical dissertation upon the management of 



these ; but it may be remarked that fish of the Salmon Family 



* Nineteen in all, but in one of these the fish, an unspawned male of 

 305 Ib., was handled in spawning operations unsuccessfully, marked, and 

 returned to the Spey at Fochabers in December, 1896. In March, 1897, 

 the same fish was retaken in the Deveron weighing only 28 Ib., and was 

 still not fully spent. It is probable the fish had been injured in the 

 attempt to use him for the hatchery at Fochabers. 



