Obviously, ranking is general and for local 

 problems it may not fit. But in the Great Lakes it 

 indicates orders of magnitude. 



Accelerated aging or eutrophication of certain 

 Great Lakes is not the sole cause or symptom of 

 deterioration of water quality. However, because 

 the effects of other pollutants are so intimately 

 linked to this phenomenon, preventing accelerated 

 eutrophication and restoring the water quality in 

 eutrophic lakes will help to improve otlier quaUty 

 problems such as oxygen depletion caused by the 

 biodegradation of organic wastes. 



It must be realized that predicting what would 

 happen to the eutrophication trend through re- 

 moval of any single nutrient source is virtually 

 impossible. While priorities should be established 

 to deal with both preventive and restorative 

 techniques, many methods will have to be imple- 

 mented before effective restoration is achieved. 



Any plan. for restoring the Great Lakes is a 

 tremendous undertaking because of the scale and 

 nature ■ of resources involved. Technology for 

 dealing with freshwater environments is not ori- 

 ented toward problems of this magnitude; how- 

 ever, technology in the marine sciences has been 

 directed toward the solution of large scale prob- 

 lems. 



Note: Eutrophication, both in the Great Lakes and in 

 general, has been the subject of much research and many 

 scientific and popular articles discuss this topic. Readers 

 will find the following papers useful: Lake Erie Basin 

 Committee, League of Women Voters, Lake Erie: Re- 

 quiem or Reprieve?, 1966; K. M. Stewart and G. A. 

 RohUch, "Eutrophication-A Review," Publication No. 

 34, State Water Quality Control Board, State of 

 Califoniia, 1967; C. F. Powers and Andrew Robertson, 

 "The Aging Great Lakes," Scientific American, pp. 

 94-104, November 1966; W. J. Oswald and C. G. Golueke, 

 "Eutrophication Trends in the United States-A Prob- 

 lem?, Journal Water Pollution Control Federation, pp. 

 964-974, June 1966; E. G. Fruh, K. M. Stewart, G. F. 

 Lee, and G. A. Rohlich, "Measurements of Eutrophica- 

 tion and Trends," ibid., pp. 1237-1258, August 1966; B. 

 Commoner, "The Killing of a Great Lake," The 1968 

 World Book Supplement to the World Book Encyclo- 

 pedia; Department of Health, Education and Welfare, U.S. 

 Public Health Service, Pollution of Lake Erie and Its 

 Tributaries-Part I, 1965. 



VM. PROLIFERATION OF PESTS AND OTHER 

 SPECIES 



The existence of or proliferation of unwanted 

 species is a problem of many regions although the 

 types and effects of the species vary considerably. 

 These include: 



—Jellyfish: Atlantic coast, especially Chesapeake 

 Bay 



-Aquatic Weeds: New England, Long Island, 

 Chesapeake Bay, South Atlantic and Gulf water- 

 ways 



—Sharks: many coastal areas 



— Alewives: Great Lakes. 



Marine pests can be a very real problem which 

 can affect the economy and the development of a 

 region, 



Man often has contributed to dramatic in- 

 creases of marine pests by increasing nutrients, 

 accidentally introducing the species, modifying the 

 salinity, or eliminating the predators. 



A. Jellyfish 



All waters surrounding the United States con- 

 tain venomous jellyfish and other related orga- 

 nisms. The East Coast and Gulf Coast States are 

 affected at times by invasions of jellyfish, leading 

 to severe restrictions of water-based activities. 



The notorious portuguese man-of-war 

 (Physalia) is virulent and sometimes so abundant 

 that it forces the closure of major beaches, and 

 gravely damages the image and quality of Florida's 

 greatest asset. The coastal areas of the New 

 England States and New York are subject to 

 intermittent swarms of jellyfish, brought to the 

 inshore areas by vagaries of the coastal currents 

 and winds. 



In Chesapeake Bay, the problem is particularly 

 acute because of the summer sea nettle {Chrysaora 

 quinquecirrhd), which on contact with a bather 

 produces a skin irritation so severe that swimming 

 in Chesapeake Bay virtually ceases when the pests 

 appear from late June to early October. The 

 common sea nettle is umbrella shaped, is about 

 eight inches in diameter and has tenacles streaming 

 up to 30 inches beneath. Under severe conditions 

 as many as 50 sea nettles per cubic yard have been 

 counted.^' The sea nettle also presents problems 

 to industrial boating and commercial fishing inter- 

 ests by clogging pump intakes and nets, causing 

 nets to rot, and causing skin irritations to those 

 handling these materials. 



L. E. Cronin, Director, Chesapeake Biological 

 Laboratory, testimony to House Merchant Marine and 

 Fisheries Committee, Sept. 28, 1967. 



III-45 



