126 REPOET OF COMMISSIONER OF FISH AND FISHERIES. [36] 



"But mackerel /Vy are found near the land, in detached sea areas, all 

 the way from the shores of Massachusetts to the shores of northeast 

 Newfoundland. 



"While the cod spawn on the North American coast during every 

 month of the year wherever the temperature of the water is sufficiently 

 low and ice does not interfere, and the herring spawn in like manner 

 during spring and fall, when the bottom waters have acquired a certain 

 temperature, the mackerel spawns, as a general rule, in the spring of 

 the year, and large schools appear to be established where the Arctic 

 current exercises its influence either as a distinct surface current, or 

 where it is brought to the surface by banks or shoals, and thus secures 

 the requisite coldness in the waters for the floating spawn. 



"The floating spawn may be drifted by winds or tides many miles 

 from the i)lace where it is shed; and the birthplace of the fish will be 

 that portion of the sea area where the young fry first issue from the 

 Gggj but not the spawning ground of the mother fish. In ordinary 

 seasons the swing of the tides, apart from local currents, brings back 

 twice every day the drifting surface matter, Avhatever it may be, near 

 to the place from which it set out; but winds may greatly alter the 

 course and distance to which floating ova would be drifted. Hence, 

 except in the case of secluded bays like the Bay of Chaleurs, Pleasant 

 Bay or Massachusetts Bay, the geographical position of mackerel fry 

 is in a great measure dependent upon the winds which may have pre- 

 vailed. A storm near the end of May or early in June on the coasts of 

 the United States may drive floating spawn far out to sea, even into 

 the heated waters of the Gulf Stream ; and it has yet to be shown that 

 mackerel spawn could survive the sudden and extreme change of tem- 

 perature this would involve; or a continuance of southerly winds may 

 drive the spawn on to the shore and destroy it. This occurs frequently 

 with the spawn of those fish which are deposited near the shore, as in 

 the case of the capelin and herring. The small size of the mackerel 

 spawn would cause it to be unobserved, and it would be more dis- 

 tributed than the spawn of the herring and the capelin. The United 

 States Signal Service charts show the course of storms and winds dur- 

 ing the spawning season, which would produce these results. 



"The relation of cod spawn to rain has been referred to elsewhere 

 (Part I, page xii). Ecasoning from analogy, which in so many in- 

 stances must be for the present our only guide, the effect of rain or of a 

 rainy month on mackerel spawn would be equally. prejudicial, by caus- 

 ing it to sink below the surface and be removed from those conditions 

 of light and oxygen which are essential to the development of the em- 

 bryo. 



"On the other hand, the spawn might be driven in an easterly direc- 

 tion, or in a westerly direction, and be hatched some miles off the coast 

 in great abundance. These new schools might attain great magnitude 

 in three or four years, being unobserved, and might so remain for sev- 



