5 o Memoir Sears Foundation for Marine Research 



Table IV. Sizes and Weights of Young Taken during 1 944 in a Peche at 

 Ste. Famille He d'Orleans, near Quebec City. 



No. of Fork Length Weight 



Date Specimens (mm) (g) 



Range Average Range Average 



August 31 25 130-144. 122.8 6.8-17.4 107 



Sept. 6-28 43 100-205 150.6 5.6-35.1 21. 1 



Oct. 11-26 40 125-201 168.5 9.9-47.7 28.0 



of good growth are afforded in four specimens, 27.8—33.3 inches FL and weighing 

 4.8—8.8 pounds; the indicated annual increases were 6.3— i4.4''/o in length, corre- 

 sponding to 28. 8-47. o^ in weight (for further details, see Vladykov, yS). 



Sturgeon 11—34 inches long from the Hudson River were 2-8 winters old, as 

 indicated by their otoliths (J5: 68, tab. 10). Otolith studies, though based on few 

 specimens, also indicate a greatly accelerated growth following the seaward migration of 

 the immature Sturgeon, if estimated ages of 1 1 years for a 75-inch fish and of 12 years 

 for two others of 88 and 100 inches are approximately correct. The maximum age, as 

 indicated by the winter marks on the otoliths, is at least 18 winters in the case of a 

 female 8 feet 8.5 inches and weighing about 225 pounds, taken from the Hudson 

 River, Maiden, N. Y., April 30, 1937.*^ Vladykov (76') has given a graph for the 

 length-weight relationship for a series of 1,592 Atlantic Sturgeon from the lower St. 

 Lawrence River, Quebec. 



Spawning and Migrations. The Atlantic Sturgeon is an anadromous species, in- 

 variably spawning in fresh water but making its growth in salt water. Adults migrate 

 from the sea to fresh water in advance of the spawning season. The spawning migra- 

 tion begins during February in the St. Marys River, Georgia, typically during April 

 in Chesapeake Bay (jp: 73-76), at the end of April and in May in the Hudson River, 

 and during May and June in the Gulf of Maine (jj: 82). The exact movements of 

 mature Sturgeon in the St. Lawrence River have not been reported, but they prob- 

 ably begin to ascend the current in May (fishing during this month is prohibited) 

 and continue to run upstream through June and sometimes in early July. 



In the Delaware River in 1925, the spawning migration started on April 23; 

 a few fish were taken during the last of April and the first part of May, with the 

 largest catches between May 12 and 22 inclusive (J5: 184). During the last week of 

 May and the first ten days of June the catch was scarcely one fish per day, and on 

 June 10 the Sturgeon fishing ceased. The gill nets (13— in. stretched mesh) were set 

 in a narrow arm of the river between Pea-Patch Island and the New Jersey shore 

 opposite Delaware City, where the channel is about 2.5 miles long, 6—7 fms. deep, 

 and the current strong. The Sturgeon gathered for spawning in the upper part of the 

 river near the eastern shore, where the bottom is hard clay. Spawning took place 



hard with their tails that the posterior ends of the caudal rays are broken, and only by slow regeneration do 

 they regain their original length. Thus some fish, after repeated recaptures within the same season, seem to have 

 grown somewhat shorter. 

 42. Age determination by Greeley, not previously published. 



