Average lengt±i in inches by age group for 

 fish collected in 1962 was as follows: IV, 10.2; 

 V, 11.8; VI, 13.0; and VII, 17.9. A marked 

 difference in growth increment between 6-and 

 7-year-old fish and 5-and 6-year-old fish is 

 apparent. The 7-year-old fish were produced 

 before closure of the dam . Growth was slower 

 than that recorded in other Missouri River res- 

 ervoirs . Six-year-old smallmouth buffalo taken 

 in Oahe Reservoir in 1959 averaged 19.9 inches 

 in length, (Fogle, 1961, op. cit.) while 4-year- 

 olds taken in Fort Randall Reservoir in 1959 

 were 15.8 inches long (Sprague, 1961, op. cit.). 

 The poor reproduction and growth experienced 

 by this species in Lewis and Clark Lake suggests 

 that it has been unable to adapt to conditions 

 found in the reservoir and that the population 

 will remain small. 



Bigmouth buffalo 



There was a small population of bigmouth 

 buffalo in the reservoir, dominated almost en- 

 tirely by the 1956 year-class (table 14). Net 

 collections indicated that abundance of this speci- 

 es declined after 1959 (table 2). Reproduction 

 was good in 1956, and young were also collected 

 between 1960 and 1962 (table 7). Average length 

 in inches by age group for fish collected in 1962 

 was as follows: IV, 9.5; V, 14.1- VI, 16.4; and 

 VII, 19.0. Growth of this species in Lewis and 

 Clark Lake was poorer than in the other Missouri 

 River reservoirs in South Dakota. Six-year-old 

 fish taken from Oahe and Fort Randall Reservoirs 

 in 1959 were 19.7 (Fogle, 1961, op. cit.) and 

 20.1 inches (Sprague, 1961, op. cit.) long, re- 

 spectively. Bigmouth buffalo will probably re- 

 main of minor importance in this reservoir. 



Blue sucker 



River (Bailey and Allum, 1962). The white sucker 

 was rare in the reservoir and was collected only 

 during the first 3 years of study. 



Northern redhorse 



The northern redhorse was a minor species 

 in the reservoir, and its apparent abundance 

 changed little between 1956 and 1962 (table 2). 

 Spawning was usually completed by the third 

 week of June. From the age-class distribution 

 o: the catch (table 15), it is apparent that some 

 reproduction occurred each year, although 

 young-of -the -year were collected only in 1956. 

 Average length in inches by age group for fish 

 collected in 1962 was as follows: I, 2.6; II, 6.8; 

 in, 10.2; IV, 12.6; V, 13.7; and VI, 16.0. 

 Growth was comparable to that found for this 

 species in Minnesota (Kuehn, 1949), but less 

 than reported in Oklahoma Qenkins et al. , 1952). 

 The northern redhorse is apparently rather short- 

 lived in Lewis and Clark Lake since most fish 

 were less than 5 years old and none were over 6 

 years of age (table 15). 



Black bullhead 



This species was uncommon in the reser- 

 voir, and its abundance decreased after 1956 

 (table 2). Trautman (1957) suggests that the blue 

 sucker prefers clear waters which may account 

 for its rarity in Lewis and Clark Lake . 



White sucker 



Although this species is common through- 

 out South Dakota, it is uncommon in the Missouri 



There was a small population of black 

 bullhead during the early years of impoundment, 

 but after 1958 it became rare (table 2). The 

 decline suggests that this species was unable to 

 adapt to conditions in the reservoir . A similar 

 history was experienced by this fish in Fort 

 Randall Reservoir where it was common for 

 several years after the reservoir was formed, 

 but by 1959, the seventh year of impoundment, 

 none was collected (Sprague, 1961, op. cit.). 



Channel catfish 



"Die channel catfish was one of the major 

 fishes in the reservoir , but most were collected 

 in 1956, the year following dam closure. Since 

 1957 its apparent abundance has been reduced to 

 about one -half that of 1956 (table 6). It was 

 generally distributed throughout the reservoir, 

 but most fish were collected about midway up 

 the lake in the old river channel . 



14 



