104 



MARINE AND FISHERIES 



6-7 EDWARD VII., A. 1907 



sea-herring of the same age, which is 29 mm., or about li inches long. The gasperean, 

 from an experiment reported to have been carried out in Maine, U.S., by Messrs. Treat & 

 Son, reaches a length only half that of the shad at the age when the shad is 3 to 5 in. 

 long (4 months old). Of course, such fishes, when confined in rearing ponds, are probably 

 dwarfed in their growth, and may not afford a certain clue to tKe determination of the 

 age of specimens captured in their native waters. Shad have, for instance, been taken 

 o to 4 inches in length in February, while specimens of the same length have been 

 secured in great numbers in September; and in the Potomac river examples 3 inches 

 long are abundant in November, while about the first of that month shad 5 to 7 inches 

 long are plentiful in the Maine rivers. • According to my observations, the first-named 

 specimens (3 to 4 inches long) naust have been hatched out in November or Decem- 

 ber, a supposition which raises a difficulty, as shad enter rivers, in December and Janu- 

 ary, on the Atlantic coast, only as far south as Georgia and Florida, while the small 

 shad of the size named, captured in September, as in the Potomac river, must have 

 been hatched in June, though the main ascent is as early as April in that river. Shad 

 9 to 13^ inches long are frequently taken in Canadian waters in October, and as these 

 fish cannot possibly be only four months old, and must be the young of the year pre- 

 ceding, especially as shad 3 or 4 inches long are also captured about the end of Octo- 

 ber, and schools of fish 4 to- 5 inches long are observed in December. We know that 

 shad are apt to migrate along long distances of sea shore, as on the Pacific coast, 

 where they have spread far from the rivers where they were originally planted, so that 

 they are not so true to their native rivers as the salmon, and this may explain the 

 very discrepant nature of the facts alluded to. In Florida shad ascend rivers in De- 

 cember, as already stated, while in the Savannah and Edisto rivers of Georgia they 

 are :Bound in January, in the Potomac in April, Delaware river in Miay^, and in the 

 Canadian rivers from the middle of May (in St. John river, N.B.) to the end of June, 

 especially in the more northerly rivers, as the Miramichi. A month later, in July or 

 August, the spawned fish descend to the sea again in very poor emaciated condition, 

 and the young fry begin to descend about the same time, but go down more slowly. 



It is, of course, a matter of much difficulty to trace the later history of the various 

 species now under review, but some principal facts may be determined. Thus the small 

 sea-herring 62 mm. (2^ inches) long taken in September cannot possibly be the fry of 

 the July spawning schools, as such fry could not be more than about 1 inch long accord- 

 ing to the foregoing account, nor is it possible for the fry hatched in April, May or 

 June to be more than 1^ to 1§ inches long, making all allowance for great variations 

 in growth. The herring If to 2 inches long found in January ofi the east coast of 

 Scotland must be five months old, if they are, as Mr. Geo. Sim held, the fry of the 

 August preceding, while similar young fish in June and July must be March fry. In 

 its second year a sea-herring is 60 to 80 mm. long (2J to 2| inches)'^ though Hjort 

 states his views that a length of 2^ inches (50 to 60 mm.) may be reached in six 

 months. The specimens of herring 3| to 4J inches frequenting St. John harbour in 

 August (Plate I., fig. 5) are not likely to be the fry of the preceding spring land only 

 four or five months old, nor of the previous fall (August or September), but of the 

 spring or fall prior to that. A year later, when barely 3 years old, the fish are 4i to 6 

 inches long (114 to 150 mm.), though Hjort again holds that in 2| years a herring 

 reaches 160 to 165 mm. (6| to 7 inches) in length.* Herring 8 to 11 inches long can- 

 not be less than 3 years old, and may be in their fourth year. Dr. Meyer decided after 

 his studies upon the herring (30 years ago) that herring 6i to 7 inclies long are only 

 2 years old, and that within one year after hatching they are 5 to 6J inches long, an 

 opinion not confirmed by more recent researches'. Sars, Nilsson, Sundevall and others 

 do not support Meyer's views. Dr. Jenkins in his recent studies at Kiel states that 

 the Baltic herring show the following growth: 1st year, 4^ to 4| inches; 2nd year, 6^ 

 to 6J inches; 3rd year,, 7^ to 7| inches; 4th year, 8i to Si inches; 5th iyear, 9 J to 91 



* The common opinion that the ' matie full * herring, 9 to 95 inches long, in Scotland is only 

 2 years old can hardly be correct. 



