. A biological survey of the Oswego River system. Supplemental to Seventeenth annual report, 1927. Fishes. 194 Conservation Department. Fig. 1.—Galvanized square foot with sieve dipper in use averages, at each station, whether or not the center of stream beds contain more nutritive elements by weight, than is found at the sides of stream beds. By comparing bottom studies made in streams under seven feet in width with those above seven feet, it is evident that these small, cold headwaters produce much more available fish food per unit area than the larger, warmer main trunks. The average weight
. A biological survey of the Oswego River system. Supplemental to Seventeenth annual report, 1927. Fishes. 194 Conservation Department. Fig. 1.—Galvanized square foot with sieve dipper in use averages, at each station, whether or not the center of stream beds contain more nutritive elements by weight, than is found at the sides of stream beds. By comparing bottom studies made in streams under seven feet in width with those above seven feet, it is evident that these small, cold headwaters produce much more available fish food per unit area than the larger, warmer main trunks. The average weight of nutritive elements per square foot of bottom in streams under seven feet is grams, for those above seven feet it is grams, a difference of grams; or in other words, streams below seven feet in width probably produce more than twice the food by weight per unit area of bottom. It is readily seen that the quantity of food organisms in streams above 18 ft. in width decrease from the shore line to the middle of the channel. At the fifteen foot (station 6) stream width the three bottom catches weighed almost the same showing that the food was fairly evenly distributed over the bottom, but still higher in the center. At the eighteen foot stream width (stations 1, 3) the food has materially decreased in the center of the stream bed. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original New York (State). Conservation Dept; New York (State). Conservation Dept. Annual report. Albany, The Department
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Keywords: ., bookcentury1900, bookcollectio, bookdecade1920, booksubjectfishes
