388 U. S. BUREAU OF FISHERIES 



although water conditions have been so unfavorable during the past 

 few years that parts of the stream have dried up completely, the run. 

 is being slowly increased through holding fish in ponds and planting 

 them during the winter months. During the past year 10,054 of the 

 fish planted were marked by the removal of both ventral fins. 

 During the winter season 455 adult fish were taken in the trap and 

 before release were tagged with celluloid disks and nickel wire. The 

 tags were placed in the anterior base of the dorsal fin. Of the fish 

 tagged the previous year approximately 7 percent returned this year 

 as compared with a return of 13 percent from the previous year's 

 tagging. The returns are quite obviously dependent on the age of 

 the fish tagged as very few fish return to spawn the third time. 



On the Klamath River 45,700 yearling trout were marked and 

 planted during May. Part of these fish were from eggs taken in the 

 Klamath River while 9,770 were from a possibly nonmigratory type 

 of rainbow taken in Kosk Creek, a tributary of the Pit River. At 

 Beaver Creek on the Klamath, arrangements have been made to install 

 a trap at the egg-taking station to take downstream migrants. This 

 will make it possible to correlate information obtained at Waddell 

 Creek with that of the streams tributary to the Klamath. 



Work was also continued on two minor projects, the Angora Lake 

 and Truckee River marking experiments. 



The Angora Lake project was started in 1933 with a plant of over 

 5,000 marked eastern brook trout. The objects of this experiment 

 are to determine: (1) Total annual production in pounds of fish per 

 acre of water as shown by anglers' catches; (2) survival rates from 

 plants of various lots of marked trout of given sizes; and (3) the 

 correlation between the actual production in fish and food conditions 

 in the lake. The lake offers exceptional opportunities for obtaining 

 complete returns from anglers, and the resort owner on the lake is 

 receiving a small annual stipend to record and weigh all fish caught. 



Returns for the fishing season of 1934 show that anglers took only 

 81 trout, having a total weight of 71.2 pounds. Since Angora Lake 

 is, roughly, of about 5 acres area, these figures show that production 

 in terms of fish landed by anglers was approximately 14 pounds per 

 acre of water surface. The average catch per angler was 2.3 fish. 

 Of species, 25 loch leven, 14 rainbow and 42 eastern brook trout were 

 taken. The figures are based upon partially complete returns. Noner 

 of the marked eastern brook trout planted in the previous summer 

 entered the catches this year, due doubtless to the fact that their 

 average size at planting was slightly under 2 inches. 



Excellent returns have likewise been obtained from the Truckee 

 River marking experiment which was started in 1932 with the plant- 

 ing of 40,000 trout. In 1933 an additional 40,000 were planted, and 

 they entered into the catch in considerable numbers during the past 

 summer. In one lot of 62 fish taken by anglers, 49 were fish of this 

 marking. 



Field studies of stream food problems were continued in Waddell 

 Creek in the spring, though lack of time and the pressure of other 

 matters prevented detailed work of the type carried on the year 

 previously. Bottom food samples were taken to determine the bulk 

 or weight of food which each group contributes to the total potential 

 supply in this stream. It was found that caddisfly larvae and pupae,. 



