bow were stocked both in October and during 

 May and June and no great differences in recov- 

 ery rates were noted. Other similar experi- 

 ments have found that "in-season" plants were 

 more successful than fall plantings, but it was 

 thought that the thermal water entering the 

 Madison might possibly lower the winter mor- 

 tality rate on fingerlings planted in October . 



None of the brown trout fingerlings 

 planted were recorded as entering the creel. 

 Westerman and Hazzard (1945) summarized the 

 results of fingerling trout stocking experiments 

 in Michigan and three other states. In 12 ex- 

 periments with rainbow trout, an average of 

 2.02 percent reached the fishermen's creel. 

 From five experiments with brown trout, 3 . 4 

 percent reached the fishermen's creel. They 

 concluded that streams with adequate natural 

 reproduction usually cannot grow any more 

 fingerlings to catchable size than are produced 

 naturally. Schuck (1948) summarized much of 

 the literature on trout stocking and restated the 

 low survival rate of planted brown trout finger- 

 lings . We must conclude that the fingerling 

 stocking of brown and rainbows in the Madison 

 River system did not contribute measurably to 

 the fishermen's creel. 



ADULT RAINBOW TROUT PLANTING 



Adult rainbow trout planted in the Madi- 

 son River in 1954 and in the Madison and Gibbon 

 in 1955 contributed greatly to the catch; of the 

 49,798 planted, 21,128 were caught by fisher- 

 men (table 5). The return of the 25,006 fish 

 planted in 1954 was 33.2 percent, while the 

 return of 24,792 fish planted in 1955 was 51.7 

 percent. The increase in recovery in the plant- 

 ings of 1955 over 1954 was probably due to the 

 fact that the trout stocked in 1955 were ten to 12 

 inches while those stocked in 1954 were eight to 

 ten inches. The anglers' catch showed a low 

 survival rate of adult rainbow trout to the year 

 following planting. A few (170) of the 1954 

 plantings were caught in 1955, but none of the 

 1955 plantings were recorded as caught in 1956 

 or 1957. 



The results of this study agree closely 

 with other investigations in the United States 

 on return of planted adult rainbow trout to the 

 angler. The State of California (1951), after 



several years of study, rejected the policy of 

 stocking catchable -sized trout in any waters 

 unless anglers could catch at least 50 percent 

 of those planted. Cooper (1953b) found that 

 rainbow trout in Michigan planted during the 

 angling season at accessible points should give 

 a return in excess of 67 percent. King and 

 HoUoway (1952) mentioned recovery rates of 53 

 and 90 percent in Tennessee. Recovery rates 

 on stocked rainbow trout in the Logan River, 

 Utah, were above 80 percent if they were planted 

 during the fishing season (Regenthal, 1952). 

 None of the studies considers the carryover to 

 the year following planting to be significant. In 

 short, their value to the fishermen is greatest 

 when they are planted virtually "in front of the 

 rod." 



There was both upstream and downstream 

 movement of adult rainbow trout following plant- 

 ing. Most catches were made, however, within 

 five miles of the location of plantings, and no 

 hatchery fish were recorded caught outside of 

 Yellowstone National Park. An organized pro- 

 gram was conducted in 1955 to determine the 

 presence or absence of marked adult rainbow in 

 Hebgen Reservoir, one mile downstream from 

 Yellowstone Park. More than 1,000 trout were 

 examined by creel census personnel and boat 

 dock operators, and no trout with Madison River 

 marks were found. 



FISH POPULATIONS 



Firehole River 



The Firehole River above Midway Geyser 

 Basin was populated principally by brown trout, 

 although a few catchable -size rainbows were 

 present (table 6). Most fish (91.8 percent) were 

 young-of -the -year brown trout. At Riverside 

 Geyser there were an estimated 528 catchable - 

 size brown trout per mile of stream; at Biscuit 

 Basin there were 597. These populations of catch- 

 able -size fish were much higher than were reported 

 in Minnesota (Smith, et al, 1949) or in Michigan 

 (Shetter and Hazzard, 1939). The age class 

 composition of the brown trout population as 

 determined from data in table 7 in the six miles 

 of stream below Old Faithful was: 0, 21,824; I, 

 1,084; II, 407; HI, 213; IV, 96; and V, 129 

 (table 8). 



13 



