Belding. — Preservation of the Alewife 97 



(c) Temporarily flooding the bogs during the early fall, thus 

 stranding the young alewives which are descending to salt water. 



Pollution. — There are two sources of pollution in the coastal 

 streams, (1) sewage, and (2) manufacturing wastes. The former 

 comes from sewage systems and from private houses; the latter 

 from mills of various kinds located on the streams. 



Pollution affects fish in three ways: (1) by directly interfering 

 with the normal habits of the adult fish, (2) by destroying the eggs 

 and young, and (3) by indirectly affecting the environment and 

 food supply. 



Overfishing. — The principal cause of the decline of the alewife 

 fishery has been overfishing as a result of unwise regulation. 

 Unless a reasonable number of adult alewives are permitted to 

 reach spawning grounds, the destruction of any fishery is inev- 

 itable. Almost universally, overfishing has been brought about 

 by faulty methods of regulating the industry through town con- 

 trol, which is the common practice in Massachusetts. The alewife 

 streams where the public is given the privilege of free-for-all 

 fishing under various obscure regulations, most of which are 

 seldom enforced, have become the poorest producers. Fisheries 

 directly operated by towns are also unsuccessful, owing to laxity 

 in management, and to town politics. The popular and easy expe- 

 dient of annually leasing the fishery to the highest bidder has 

 placed a premium upon its exploitation, and has directly encour- 

 aged overfishing. Naturally the purchaser, uncertain of obtaining 

 the fishery for the future years, would drain its resources to the 

 utmost by taking all available fish. 



III. Remedial Measures. 



As briefly outlined in the previous pages, the biological investi- 

 gation of the Massachusetts alewife fishery has shown its present 

 condition, the causes contributing to its decline, and has brought 

 out certain points in the life history and habits of the alewife 

 which furnish a basis for establishing cultural methods. 

 The requisite steps in this reconstruction work are: 

 (1) An unobstructed and uncontaminated passageway from 

 salt water to the spawning grounds. 



