. A biological survey of the Oswego River system. Supplemental to Seventeenth annual report, 1927. Fishes. 52 Conservation Department The Bottom Fauna.— During our survey a large part of our efforts were directed to the study of the bottom fauna to discover the principal source of the primary fish food in the lake. Six hun- dred and thirty-two samples of the bottom were taken with the Ekman dredge during the three months and carefully analyzed. To supplement these studies 212 samples were taken with the scoop dredge in localities where the Ekman could not be worked satis- factorily and several
. A biological survey of the Oswego River system. Supplemental to Seventeenth annual report, 1927. Fishes. 52 Conservation Department The Bottom Fauna.— During our survey a large part of our efforts were directed to the study of the bottom fauna to discover the principal source of the primary fish food in the lake. Six hun- dred and thirty-two samples of the bottom were taken with the Ekman dredge during the three months and carefully analyzed. To supplement these studies 212 samples were taken with the scoop dredge in localities where the Ekman could not be worked satis- factorily and several hundred samples* were taken in the shal- lows near shore with a Needham dredge. We find as a result of this work that in the shallow water of all the lakes there is a fair supply of snails, bivalves, and insect larvae, principally mayflies, caddisflies and midges, ranging to a depth of 50 feet. The abundance of these forms in shallow water, however, is not sufficient to supply a preponderant fauna of shallow water. Lowering Ekman dredge for a sample of lake bottom fishes. The minnows, likewise, which are mostly confined to the shallow water of the lake are not abundant except in a few favored localities. In the deeper waters we find in all the lakes a plentiful supply of the small .crustacean (Pontoporeia hoyi),oi chironomus larvae, a fair supply of small worms (OligocJiaetes) and a fair supply of bivalves. (Spliaerium). Likewise in most of the lakes near the bottom a fairly plentiful supply of the small crustacean (Mysis). These forms are the food of young trout, whitefish, etc., and are often eaten by the larger fish when other supplies fail. In Keuka, Cayuga and Skaneateles lakes we took specimens of Pontoporeia filicornix. * The determination of the organisms captured was the work of Dr. Thomas Smyth of South Carolina Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and ap
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