OF THE HABITS AND MIGRATIONS OF THE MACKEREL. 19 



One important observation made during the early days of March, 

 1891, is recorded by Marion,* which shows that mackerel may be 

 present in deep water when not visible at the surface. After a strong 

 mistral the trawls of the "bateaux boeufs," fishing six miles from 

 shore off Cape Couronne, caught numbers of mackerel at depths of 100 

 to 150 metres. Marion considers that this accidental capture demon- 

 strates completely that the mackerel leave the surface and descend into 

 the deep water when the upper layers are agitated by strong winds. 

 This observation will be again considered and discussed in relation to 

 others. 



After the advent of the spring schools fishing is abundant in the 

 Mediterranean (Cette), off the west coast of France, off the south-west 

 of Ireland, in the western portion of the English Channel, and off the 

 north coast of Cornwall. Mackerel are not, however, yet (April) taken 

 in numbers in the eastern portion of the English Channel, in the North 

 Sea, or on the coast of Norway. 



In the Mediterranean the mackerel caught in April are breeding fish. 

 On the other coasts the shoals are composed of large fish about to 

 breed, but their reproductive organs are not yet ripe. The fish captured 

 off the south-west of Ireland appear to be the finest, and command 

 the best prices. 



America. — On the American side of the Atlantic mackerel make 

 their first appearance at some distance from the coast, off Cape Hatteras, 

 at about the same time of year as they appear on the Irish coast. The 

 following list of dates of first catches is taken from the Bulletin of the 

 U. S. Fish Commission, vol. vi., 1886, p. 107. 



Year. Date. Year. Date. 



1879 . . April 13 1883 . . March 31. 



During April the fish move gradually northwards, but do not go close 

 to the shore. By the end of the month they are generally found off the 

 capes of Delaware. 



Until the year 1886 it was the custom of the American mackerel 

 fishermen to go southwards in March, and capture these early shoals. 

 Many of the shoals were composed of large fish just about to spawn, 

 but the condition of the fish was not equal to that of those caught later 

 in the year, which had been feeding on the coast for some time. As 

 the fish did not readily take bait at this time, they were caught in 

 purse-seines. In 1887, to endeavour to counteract the considerable 



• Ann. Mus, Nat. Hist. Marseille Zool. Appliquics, 1891, p. iii. 



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