204 JURA. HERRING. 



From the deep water they arrive early in the summer 



on the western coast, but are rarely taken in abundance 



till August, recently, not till September. On the eastern 



side of the island they are later, but extend much further 



along the shore ; while, of late, they are also much more 



plentiful on this than on the former coast. This change 



of haunts is one of the most obscure points in the history 



of the herring. It has visited and deserted in succession 



almost every loch on the west coast ; and in those which 



were once the seat of the fishery, not a fish has for many 



years been taken. At present they seem to prefer the 



inlets of the Clyde ; formerly, the northern lochs were 



most productive. With that change from the north to the 



south, the season of shoaling has also become much later. 



It is equally remarkable that when the boat fishing has 



ended on the west coast, from their desertion of the shallow 



waters, the most abundant fishery is generally found on the 



eastern ; although these are evidently not the same shoals, 



since the fish are in a different state. When the herring 



fishery was expected to prove a mine of wealth, expensive 



establishments were formed on the north-west shore, as 



was noticed in describing Tanera; all of which have for 



many years become useless. 



There is similar obscurity respecting the periods of 

 spawning, which appear to vary on the different coasts ; 

 although supposed, from its importance, to be an unvary- 

 ing circumstance in the habits of animals. It may pos- 

 sibly arise from their breeding more than once in the 

 year, and from that process being at different seasons 

 performed in different places, according to the variations 

 of circumstances which we have no means of ascertaining. 

 Thus only does it appear possible to explain the different 

 conditions in which tfyey are taken at the same time on 

 different coasts ; and the greater confusion which occurs 

 by occasionally taking fish in the same place in all condi- 

 tions. In the western fishery they are always empty and 

 in a high state of feeding ; being thus much more valuable 



