REPORT OF COMMISSIONERS OF INLAND FISHERIES. 55 



43. Brevoortia tyrannus (Latrobe). Menhaden; Pogy; Bony Fish. (Plate 

 XII.) 



Geog. Dist.: Xova Scotia to Brazil. 



Migrations: The migrations of the menhaden are largely determined 

 directly by the water temperature; they enter the coast waters in the 

 spring when the average harbor temperature reaches about 50°F, and 

 leave in the autumn when the temperature falls below that point . 

 The approximate times of the arrival of the first schools is given as fol- 

 lows by G. Brown Goode: Chesapeake Bay, March and April; New 

 Jersey, April and early May; south coast of New England, late April and 

 May; Cape Ann, middle of May; Gulf of Maine, last of May and June. 

 They leave the Maine coast in September and October; Massachusetts, 

 in October, November, and December; Long Island Sound, November and 

 December; Chesapeake Bay, December; Cape Hatteras, January; further 

 south they remain throughout the year. It will be seen that they arrive 

 somewhat later than the shad and alewife, about the same time as scup, 

 and in advance of the squeteague and bluefish, and remain longer in the 

 autumn than any of these, except possibly the two last-named species. 

 This order of appearance is what would naturally be expected in view of 

 the fact that the squeteague and bluefish are both carnivorous and feed 

 largely upon the schools of the menhaden. 



Season in R. I.: They appear last of April or first of May and are present 

 throughout the summer and fall. Most abundant in May when first arriv- 

 ing and in October when the falling temperature is driving them away 

 from northern shores. They finally leave in November and December. 



Reproduction: Spawns in December, probably, and in May and June; the 

 location of the spawning grounds is at present uncertain. 



Food: The whole food supply of this fish is obtained by filtering out from 

 the surface stratum of water the organic life there suspended. The ar- 

 rangement of the gill rakers forms a very effective filter of the water 

 which the fish takes in by swimming actively in circles through the water 

 with widely opened mouth and expanded gillcovers. The stomach gener- 

 ally appears comparatively empty, but usually has a small quantity of 

 what appears to be a dark greenish or brownish mud, with a variable 

 quantity of copepods and small Crustacea intermixed. This may be de- 

 monstrated by observing the habits of the living fish, by the study of the 

 giU rakers, and by collecting on a filter the organic matter suspended in 

 a given quantity of surface water and by comparing the matter thus fil- 

 tered out with the stomach contents of the menhaden. The following 



