and number and species of fish caught* Data ordinarily were secured 

 from one member of the party. Data obtained were compiled for 2-week 

 periods^/ and applied to fishermen observed but not contacted and 

 those known to be present on check days in the same period of time. 

 Total estimates of fisherman-day use and yield in numbers of fish 

 for each check area were based on a summation of estimates obtained 

 for the 2-week periods. 



An attempt was made to secure weights and measurements of 

 a nonselective sample of the various species of fish from each check 

 area, but this was not always possible because most fishermen cleaned 

 their fish before leaving the water. Further, so few specimens of 

 some species were taken that adequate samples could not be secured 

 for an individual check area or even a section. In view of these 

 difficulties, these data were combined, by species, for each of the 

 three sections of stream and the two reservoirs, and the average 

 weights thus obtained were applied to the estimated yield in numbers 

 of fish from each check area within the respective sections to de- 

 termine the yield in pounds of fish. Because of lack of an adequate 

 sample, average weights obtained in one section were sometimes applied 

 in other sections. In a few instances, the average weight was esti- 

 mated. 



A short section of stream immediately above Madison Reser- 

 voir (lower section of Channel Check Area) can be reached readily 

 only by boat. Although use of boats for fishing was prohibited on 

 this section of the river, a number of fishermen used them to reach 

 the area from Madison Reservoir and then walked a short distance up 

 the river to fish. It was most convenient to check these fishermen 

 in 19S>0 in connection with the census of Madison Reservoir; and for 

 the purpose of this report, it has been assumed that the estimated 

 use in 19^0 and the yield therefrom was similar to that in 1951 and 

 was in addition to other estimates secured for the area in 1951. 



Definition of terms used in this report are: party, one 

 or more fishermen who made a trip together, usually in one car; 

 fisherman-day, one day of fishing by an individual fisherman irre- 

 spective of the number of hours involved; pole-hour, one hour of 

 fishing effort by an individual fisherman (synonymous with fisherman- 

 hour since Montana law permits only one pole per fisherman); and 

 rate of catch, average number of fish or pounds of fish caught per 

 pole-hour. 



Fisherman -expenditure data were obtained on a party basis 

 from virtually all parties contacted for creel data. These included 

 the point of origin of the trip (for miles traveled); days in the 

 trip; and expenditures per day for food, lodging, bait, rentals, and 

 miscellaneous items such as refreshments, film, and ice. 



3/ Compilations were made on a weekly basis in 1950* 



lli 



