of previously tagged fish. The low angler return and high return to traps 

 suggests that the population of large crappie is small. 



Bass 



Largemouth bass (Micropterua salmoides) were introduced into the reser- 

 voir in 1964 and again in 1972-73, but are rarely taken by fishermen. While 

 smallmouth bass (Miurooterus dolomieui) have never been stocked in the reser- 

 voir, they are reproducing and beginning to play an important part in the 

 angler's harvest. Correspondence from the Wyoming Game and Fish Department 

 (Mueller 1973) indicates that smallmouth bass were stocked in a strip-mine 

 pond near Sheridan and that high spring flows from the Tongue River washed into 

 the ponds, introducing smallmouth into the river and subsequently into the 

 reservoir. 



Catch Rates and Distribution . Catches of smallmouth bass have been small 

 in trap nets, ranging from 0.01 fish per net night in 1972 and 1973 to 0.06 

 fish per net night in 1975 (table 25). In 1976, however, the catch increased 

 to 0.23 smallmouth per net night. Zone B produced 83.3 percent of the catch 

 in 1975 and 50.0 percent in 1975. The largest number of smallmouth were taken 

 in May both years. Largemouth bass have been nearly absent from trap-net sam- 

 ples. 



Gill nets produced smallmouth beginning in 1972, and catch rates increased 

 from 0.1 fish per net in 1972 to 1.9 fish per net in 1976 (table 26). Large- 

 mouth have been absent from gill nets also. The average length and weight of 

 smallmouth taken in gill nets decreased from 251 mm to 304 g in 1975 to 217 mm 

 and 168 g in 1976, indicating the recruitment of young fish into the population, 



A baseline index of reproductive success was established with 100-ft shore 

 seine and a 50-ft bag seine. Seine hauls covering approximately 15-30 m of shore 

 were made to obtain bass fry and juveniles. When all size groups were combined, 

 date from 1975-50-ft seine, the 1974-100-ft seine, and the 1975-100-ft seine 

 were relatively consistent, (table 35). Zone A had the fewest smallmouth and 

 largemouth fingerlings per 100 m of shoreline; zone C had the most (Gregory and 

 Penical 1975). There were more largemouth than smallmouth fingerlings per 100 m 

 in zones C and A and fewer in B. For all areas combined, largemouth bass 

 made up 78.0 percent of the finger! ing catch and smallmouth the other 22.0 per- 

 cent. 



Size, Age, and Growth . Penkal (1977) found that scale annuli of small- 

 mouth bass in the Tongue River Reservoir were formed beginning in July and 

 were complete by early August. The scale-length relationship was calculated 

 and used as a correction factor for back calculation of smallmouth bass growth 

 (table 36). Growth of smallmouth bass in the Tongue River Reservoir is above 

 average for a northern lake. Calhoun (1966) reported a range for northern lakes 

 of 246 nrn (Michigan) to 310 mm (Minnesota) for fish at their fourth annuli. 

 The average length of the 1972 age class in the Tongue River Reservoir was 

 308.3 mm. This good growth could be attributed to the smallmouth's recent 

 exploitation of the new habitat or to favorable environmental conditions. 



The growth of largemouth bass in the reservoir was also investigated by 

 Penkal (1977). A summary of the back-calculated growth of largemouth is shown 



104 



