40.-NOTES ON THE IRISH MACKEREL FISHERIES. 



BY REV. WILLIAM SPOTSWOOD GREEN, 



Inspector of Irish Fisheries. 



The great herring pond, as the Atlantic is often called, is not only a means of 

 facilitating the communication of men living in countries 2,000 miles apart, but it also 

 affords the means by which certain fish can wander from the shores of one country to 

 the other. 



The mackerel (Scomber scombrus), owing to the similarity of the species on both 

 sides of the Atlantic, seems to point to intercommunication. 



In the following notes which, owing to the press of other duties, have been com- 

 menced only forty-eight hours before the date for posting, I shall allude to one of 

 our great Atlantic fisheries, and this 1 am able to attempt, owing to the knowledge 

 I have gained of the American fisheries from the valuable publications of the IT. S. 

 Commission of Fish and Fisheries, and from my interesting but too brief visit to the 

 hospitable roof at Woods Holl in Massachusetts. 



The spring mackerel fishery. — This, the most valuable of the Irish sea fisheries, com- 

 mences on the west coast of Ireland in the end of March or the early part of April. 

 On the 6th of April in this year (1893) and on the 1th of April last year the first large 

 takes were made. Owing to the observations made on the American coast as to tem- 

 perature, I was led to make similar observations here, and I found that the night on 

 which the open-sea temperature reached 50° was the night on which the large 

 schools appeared. The fish were taken by boats near shore and for over 20 miles to 

 sea. All along the coast the boats had shot their nets with little or no result for over 

 a week previous to the date named. In 1892 I shot a train of mackerel nets 10 miles 

 outside the Arran Islands off Galway Bay on the 11th of March, aud again on several 

 following nights when the sea temperature was 46° and air temperature 37°, with 

 frequent snow showers. On each night we captured two or three mackerel and a few 

 herrings. The mackerel were of small size, about 13 to 14 inches long. They were of 

 both sexes and about half ripe. This went on until April 6; then the sea temperature 

 rose to 50°, and large mackerel, 19 inches long and between 2 and 3 pounds in 

 weight, were immediately captured in thousands all along the coast. There seems, 

 therefore to be a few mackerel always to be caught, possibly wanderers from the great 

 body. How far mackerel may thus be scattered all over the North Atlantic and the 

 abundance of the supply are as yet unknown. 



Auother fact to be considered is that though mackerel are not captured in the 

 open sea in any large quantities until the sea temperature reaches 50°, still the canoes 

 and row boats which can shoot their nets close to shore and in certain bays get the large 



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