Table 11. GREAT LAKES 

 (in millions of dollars) 



1 . Bureau of 



Less than $50,000. 



Figure 8. Scripps oceanographic model tank 

 for simulating waves and other ocean phe- 

 nomena is an example of the unique labora- 

 tory facilities required for oceanographic 

 research. (University of California photo) 



distribution and abundance of organisms must be 

 obtained to make the most effective use of this 

 rich region. 



Lack of basic understanding prevents the effec- 

 tive use of near shore waters. On the one hand, the 

 ill effects of our actions cannot be foreseen in 

 time to correct them; on the other, when irre- 

 versible harm might occur, we do not know how 

 to prescribe the right amount of corrective action 

 and are forced to base regulations on the most 

 conservative estimate of probabilities. The solution 



of engineering problems suffers from the lack of 

 knowledge of the dynamics of inshore water 

 movements. There is no theory suitable to describe 

 the turbulent motion of water particles in the surf 

 zone, nor can our instruments accurately measure 

 currents in this area. 



In the process of altering our land and water for 

 beneficial purposes, man frequently produces 

 catastrophic side effects. Dredging is carried on for 

 a variety of reasons: 



—Creation and maintenance of navigable channels 

 and inlets for commercial and recreational use; 



—Creation of useful property, marinas, recrea- 

 tional areas; 



—Improved flushing action in bays, and estuarine 

 creeks; 



— Conmiercial mining of sand and gravel. 



It is not only what is done along the shores that 

 affects coasts and beaches, action far upstream 

 may have drastic consequences. The flushing of 

 minor embayments within estuaries is heavily 

 influenced by seasonal fluctuations in salinity, 

 largely through natural changes in river flow. 

 Regulation and evening-off of river flow may 

 prevent flushing action and allow a buildup of 

 predators which rob shellfish beds of much of 

 their richness. Basic research in microscale estua- 

 rine circulation must continue if predictions of the 

 effects of our actions in regulating the flow of 

 rivers are to be made. 



A classic example of side effect has been the 

 invasion by the lamprey eel^ when the upper 

 Great Lakes were opened to the sea possibly as 

 early as the opening of the first Welland Canal, in 

 1833, and certainly by the time of the deepest 

 (and fourth) canal in 1932. The eel brought a 

 cycle of biological change which has already 

 destroyed most of the lake trout. Immigration of 

 alewives into Lakes Erie and Michigan and their 

 large populations has resulted in the shores of 

 Lake Michigan being littered with millions of dead 

 alewives. Furthermore, a new ecological balance 

 has yet to be reached. 



The Spread of the Sea Lamprey Through the Great 

 Lakes, Hubbs and Pope, Transactions of the American 

 Fisheries Society, 66, 1937. 



1-26 



