NOTES ON LAKE TAHOE, ITS TKOUT AND TROUT-FISHING. 



141 



In the littoral regfion, tho following Cladocera were found: llyoci'ijptus acutifrons 

 Sars, EiD'ijcercus lameUatus O. F. ^Nliiller, Acroperus harpx Baird, Alona affinis 

 Le3'dio-, Chydorns sjdinericus O. F. Midler. 



JEpischura and L>tap1oint(s de.serted the upper 5 feet of water on bright, sunny 

 days, but both came to the surface at night. The latter was very abundant at the 

 surface at night. Daphnla InjaHnn descended to a depth of -10 feet during the day- 

 time, but came to the surface at night. Daphnla pulex descended to a depth of 50 

 feet in the daytime, but was found at the surface at night. The two Daphnia were 

 found this near the surface in the daytime only in the shallower water, where the 

 transparency was only about 52 feet. In the deeper water, where the transparency 

 was greater by 13 feet, neither form was found in catches that did not reach a depth 

 of 75 feet. Thus the diurnal migration of D. hyalina was at least 40 feet in the 

 shallower, less transparent water and about 75 feet in the deeper, more transparent 

 water, while D. p)ule.r showed a daily migration of 50 to 75 feet. These migrations 

 were greater than any noted for these forms in Wisconsin lakes or in Winona Lake, 

 Indiana. In these instances the maximum movement of D. Jiyalina was only 22 

 feet and of D. puJe.c a little less than 40 feet (Juday, 1903 and litO-i:). 



THE TROUT OF LAKE TAHOE. 



Species^ size, alnindance, etc. — Oidy two kinds of trout are caught in any consider- 

 able numbers. These are Salmo henshawi (Gill & Jordan), which has several common 

 names, such as Lake Tahoe trout, Truckee trout, pogy, and snipe; and also Salmo 

 tahoensis (Jordan & Evermaun), which is commonly called the silver ti'out of Lake 

 Tahoe. Locally, the males of the former are frequently called redfish becauce they 

 have cojjper-colored sides during the breeding season. 



The Tahoe trout, or pogy, is caught chietl}' along the western side of the lake and 

 at the south end. A large area extending south a few miles from Observatory Point 

 seems to be a good feeding giound for them, and this is the favorite fishing ground 

 of the anglers located in the vicinity of Tahoe City. Silver trout are most abundant 

 in the northeastern part of lake, in Crystal Bay and Sand Harbor, but a few are 

 caught in other parts. The Tahoe trout is caught in much greater abundance than the 

 silver trout, but it does not attain such a large size. The former rarelj' exceeds 

 a weight of six pounds, while specimens of the latter have been caught which exceeded 

 this weight by several pounds. The following measurements and weights of trout 

 caught in Lake Tahoe are given by Treat (1904, p. 800), who does not, however, 

 indicate the species he measured and weighed: 



Some 3'ears ago the Mackinaw trout, Cristivomer namaycvxh (Walbaum), was 

 introduced, and examples of it are caught occasionally in the southern pai"t of the 

 lake. During the .season of 1903, a lO-pound trout of this species was caught in the 

 vicinity of Glenbrook. 



