BIOLOGY AND NATURAL HISTORY 97 



manner the fluctuations of the menhaden in the Gulf of Maine, and it is 

 worth while to quote the following: 



Perhaps the most interesting aspect of the occurrence of the menhaden in the 

 Gulf of Maine is that it fluctuates tremendously in abundance from year to 

 year, periods of great plenty alternating with periods of scarcity or entire 

 absence from our waters. Thus 1845 was a "big year," while in 1847 pogies 

 were very scarce. Then for some years prior to 1875 they were tremendously 

 abundant off the coasts of Massachusetts and Maine every summer, and a 

 considerable menhaden fishery grew up on the Maine coast. Since then the 

 local stock has undergone the most violent fluctuations imaginable, of which 

 abundant testimony is to be found in the files of the Bureau of Fisheries. Thus 

 very few menhaden were taken in the Gulf during the cold summer of 1877 

 until September and October when they were reported as about as abundant 

 as normal. Practically none appeared north of Cape Cod in the year 1879, ^s 

 striking an abandonment of a considerable area by a fish previously abundant 

 there, perhaps, as has taken place within recent times. 



The following is a summary taken from Bigelow and Welsh (1925) show- 

 ing the years of abundance and scarcity: 



These fluctuations are no doubt controlled by biological factors such as 

 temperature and food. It seems to be the consensus that the primary factor 

 is temperature, particularly where complete abandonment or severe diminu- 

 tion in numbers is concerned. Other conditions, however, are known to 

 affect the local movements of menhaden. It is a common occurrence for inept 

 or greedy fishermen to break up schools, causing them to sound or to run 

 to open sea. 



Natural enemies also affect the local movements of menhaden. Friedlaender 

 relates in September, 1882, that very large bodies of menhaden appeared 

 along the Long Island coast between Fire Island and Rockaway Inlet. He 

 attributes the presence of this mass of fish in this area to the abundance of 

 sharks which had driven them in. 



Smith (1896) cites two interesting cases where bluefish apparently affected 

 the migration of menhaden, one case in Long Island Sound and another off 

 the North Carolina coast. He reports that menhaden were held in Gardiner 



