222 Conservation Department 



In an effort to explain such large variations, complete notes were 

 kept on depth, current velocity, shade and type of bottom. A 

 later examination of this data in the laboratory showed that the 

 most important of these influences were type of bottom, A^elocity 

 of current and depth. The relative influence of each factor is 

 very difficult to determine but of those mentioned above, type of 

 bottom seems to be the most important.* Table 2 gives a few of 

 the general results derived from two seasons' work on the distri- 

 bution of bottom foods. A comparison of the averages shows that 

 slightly less bottom foods were available per unit area during the 

 past summer than was available during the summer of 1927. If 

 yearly variations are no larger than those indicated in this table, 

 they may be considered as inconsequential in relation to fish life. 



Table 2. — Comparison of the Productivity of Streams Studied in 1927 and 1928. 

 Given by Gram Weight of Food per One Sq. Ft. as Found Under Varying Conditions 



1927 1928 



Average for streams below 7 feet in width 2 . 36 2 . 06 



Average for streams above 7 feet in width 1 . 04 . 94 



Average for all streams regardless of width 1.21 1 . 05 



Average for streams flowing through non-cultivated lands .... 1 . 36 



Average for streams flowing through cultivated lands .... 1 . 06 



Average for pools in all types of streams . 26 0.21 



Streams flowing through v/ild, uncultivated lands such as are 

 found in the Adirondack region in this state, are generally con- 

 sidered to contain more natural foods such as mayfly nymphs, 

 caddisfly larvae and other aquatic insects than streams which flow 

 through cultivated lands. A week was spent during the past sum- 

 mer working the headwaters of Point Rock and Fish creeks near 

 Constableville, N. Y. in an effort to ascertain whether or not 

 streams flowing through wild conditions are actually more produc- 

 tive in bottom foods. Twelve unit area studies were made in this 

 region and gave an average production of 1.36 grams per sq. ft. 

 The bottom studies taken near Ithaca, N. Y. in streams draining 

 cultivated lands gave an average of 1.06 grams per sq. ft. From 

 these figures, streams flowing through wild lands are somewhat 

 richer in food per unit area. However, more data must be avail- 

 able before this fact can be definitely determined. 



It will be noted in Table 2 that the average weight in grams of 

 the nutritive elements per sq. ft. in pool bottoms was 0.26 grams 

 in 1927 and 0.21 grams in 1928 which shows a negligible decrease. 

 The average for all streams regardless of width was 1.21 grams in 

 1927 and 1.05 grams in 1928. It would be well to state here that 

 these averages "over all streams", as expressed in Table 2, mean 

 the average production per unit area in the 7'iffles in streams as 

 contrasted with the pools. Tlie riffles are the larders of the streams 

 and it is here tluit the bulk of the fish food is produced. Pools, 

 as has already been shown, are lacking in quantities of food, but 



* Lack of space did not permit insertion of full proof of all statements made. This 

 will be found in the files of the Limnological Laboratory of Cornell University. 



