RAINBOW rnOUT 



HAVE BEEN RELEASED IN THIS AREA 



nmiRN TAGS TO INSURE BHIER FiSHING 



M sun TO INCIUM THIS INIOOMAttON 



) Dots Ih. -o-t -tu tofcw 



X Plot* IbfflfH in relation 10 land' 



brM««> coodi bain, otc 



RETURN ALL TAGS 



to CALIFORNIA DEPARTMENT OF FISH AND GAME 



TAKE ONE 



FRflMKEI) EHyfLoPtS 

 FOR /OUR 



TAG RLTURN 



Board designed by department to encourage tag returns. 



(Fish and Game Photo) 



Since the hatchery and planting program takes up 

 the largest portion of the department's fisheries 

 budget, a major effort was put forth in exploring and 

 developing methods to assure that the public will re- 

 ceive maximum value from the planted fish. 



NEW TAG DEVELOPED 



A special tag was developed from vinyl plastic. It 

 is placed under the thin skin covering the ventral sur- 

 face of the trout, but does not affect growth or be- 

 havior of the fish. It has enabled the research workers 

 to follow particular groups of planted fish and to 

 determine, through the return of these tags, many 

 things. These include total catch of the planted fish, 

 migration from the area of plant, growth of the trout, 

 and overwinter survival— in essence, the value of the 

 planted trout to the angler. 



Special tagging studies were carried out on various 

 types of waters receiving large plants of catchables. 



Some of the waters on which the department made 

 test evaluations are: South Fork of the American 

 River, El Dorado County; South Fork of the Yuba 

 River; Lake Pillsbury, Lake County; Big Bear Lake, 

 San Bernardino County, and the Kern River in Kern 

 County. 



Tag Returns Encouraged 



A great deal of publicity was given to the studies 

 at the latter two waters in order to encourage tag 

 returns. An added incentive for tag return was the 



donation of money and awards by sportsmen and local 

 businessmen at public drawings. 



Other waters of the State will be studied to deter- 

 mine whether they fall within the observations made 

 to date. Ultimately, through the methods used here, 

 fisheries managers in the regions will be able to deter- 

 mine more effectively the value of catchable trout in 

 their particular areas. Adjustments will be made from 

 w ater to water to utilize more effectively the hatchery 

 product. Total planting of catchables on some waters 

 will be increased and others decreased to the general 

 good of the fishing public. 



The comparison of different species and strains of 

 trout in various types of California waters mainly in- 

 volved the planting of different lots of marked hatch- 

 ery fish and the checking back of returns to the 

 angler through intensive creel census studies. Other 

 work performed in conjunction with this phase of the 

 project consisted of comparing survival of trout 

 planted by air with others planted by truck or pack- 

 stock. These studies were conducted at Castle Lake 

 in Siskiyou County, Rush Creek in Mono County, 

 and at several lakes in the Lakes Basin Recreation 

 Area of Sierra and Plumas Counties. 



Castle Lake Study 



The results of the eastern brook trout phase of the 

 Castle Lake study were published in April, 1956, issue 

 of California Fish and Game. Some of the more im- 

 portant points brought out by this study are the fol- 

 lowing: 



\. After the removal of the predatory brown and 

 lake trout in 1946, the survival to the angler of eastern 

 brook fingerlings jumped from 1.9 percent to 35 per- 

 cent of those planted. 



2. Although 1,503 pounds of yearling brook trout 

 were planted in 1947, only 978 pounds of fish from 

 this plant were eventually caught by the anglers. In 

 marked contrast, 100 pounds of brook fingerlings 

 planted in 1948 yielded 923 pounds to the anglers. 



3. If predatory fish are not present, brook trout 

 fingerlings when planted will yield a high return to 

 the angler, and many will remain in the lake to spawn 

 and establish a large self-propagating population. 



4. In Castle Lake at least, the brook trout is rarely 

 cannibalistic, so if too many are planted or if too 

 many are propagated naturally the food supply of 

 the lake will not be sufficient, and thin, stunted trout 

 will result. 



5. The average catch of brook trout by the anglers 

 was about 10 pounds per acre per year. 



Tmto Important Studies 



Some of the facts gathered in the Lakes Basin 

 Recreation Area and at Rush Creek which could 



