The Productivity of Fish Food in Oneida Lake 135 



Localities Examined in the Vicinity of Lower South Bay 



Several localities outside the area of Lower South Bay were 

 examined quantitatively and will be considered at this time. 

 Two main localities are included ; one at the west end of 

 Dunham Island and the other the shore of the main land 

 from Norcross Point eastward. The majority of the habitats 

 examined have a boulder bottom. 



Dunham Island. A wide, sandy shoal, covered by one to 

 six feet of water, lies between Dunham and Frenchman 

 Islands. Within the 6- foot contour there is an area con- 

 taining about 38 acres. Eleven unit areas (16 square inches) 

 were examined, the average number of mollusks being 204.09 

 and of associated animals 77.27, a total average of 281.36. 

 These averages indicate a population of 3,040,434,856 mol- 

 lusks and 1,151,131,370 associated animals and a total animal 

 population of 4,191,566,226.* These figures indicate that the 

 territory between the islands is the richest in animal life of 

 any portion of the lake yet examined by me, having eight 

 times as many animals per unit area as in the highest popu- 

 lated area of Lower South Bay (mud bottom, average 36.66 

 per 16 sq. in. unit). Just why this area should be so thickly 

 populated is not known at present. The great abundance of 

 life in this territory was clearly indicated by the examination 

 of a small part of a submerged log (100 square feet) cov- 

 ered with the filamentous alga Cladophora fracta in which 

 was found 2,106 mollusks and 624 associated animals, a total 

 population of 2,730. As the log was estimated to be twelve 

 feet long, there were present, on the basis of this average, 

 70,761 animals of which 54,587 were mollusks (fig. 42). The 

 algge bordering the shore was also filled with animals (fig. 44). 



The water willow in these habitats was thickly populated 

 with the mollusk B.ythinia tentaculata, a single plant having 

 from four to ten individuals, and averaging 7.66 on each 



* The computations for this population are as follows : 43,560 square 

 feet X 144 square inches = 6,272,640 square inches, -^ 16 square 

 inches = 392,040 unit areas in one aci'e, X 38 acres = 14,897,520 units in 

 38 acres, X 204.09 mollusks = 3,040,434,856 mollusks and the same unit 

 areas X 77.27 associated animals = 1,151,131,370 associated animals. 



