recoverec. 



Forage rish 



id 5.6 through age groups to \T (Table 20). Age 



groups I through 'Vll were present in 1949 (26 



-; fish) with a distinct mode in the distribution 



represented by the 1947 \-ear class (57.7 per- 

 cent). This strength of year class was not 

 evident in the 194S data. 



Gizzard shad: — In 1948 adult gizzaid shad 

 were very rare, but is \'^4^ -Sige fish predomi- 

 nated. Of the 1,009 cc - the latter year, 



71- . " — 11.0: ' ches in length 



(Ti :s differ-. , r resents the 



most extreme variation in size-class structure 

 betwesi the tw : - ' "' any one spjecies 



?T3 the fish : in appreciable 



:-. vears. 



C£^p;--^ 



in aging earn ir; 



;. Wis experiencec 

 Dnd Tear of life. 



groups were represente ^ - - - sample 



which ri-rr: _7 - "" - - (Table 



18). A- - . , -was 



of age r r : Specimens of age group in 



comprzsez i zistinct mode, saggesting the 

 crrjrrence of a ~rrrr :^45 year class. Scale 

 -S were r - ^ -4-' . 



Spotted sucker: --.*.ge groups I, n, HI, 

 V, and M of the 3p:::t: -_;serwere represente: 

 in the 1948 colli - - ::?:- T=ble 19). Age 

 grouje I (194~ — =7; . 1-43 year 

 class) constituted 75.0 and 17.5 percent, re- 

 spectively, of the t--: - — The 1944 year 



class was missing - year class was 



represeijtted ir- ; iish. In the 1949 col- 



ler*'- ---•:- _ 1947 year class again 



w£ .th 45 . 1 percent of the total . 



iar class, of which only one was 

 . — •-:._ m 1948, accounted for 15.0 percent 

 of the 1949 collecticm. Two specimens of the 

 1944 year class we r -43 year 



cla^- -^i- ?till prei-;.. ; :: .=a). It is 



ar: it the 1948 sample gave little indi- 



cation o: the real year-class strength, with 

 the exception of the 194" hatch. 



Fresrwater cra~x:--~' ■ -." 



drum taken in the i->~i> collr 



Northern river carpsucker:--Stx northern 

 river carpsuckers. Carpiodes carpio carpio 

 (Rafinesque). of age group 0. three of age group 

 I and one of age group M comprised the entire 



1948 collection (Table 18). 



Northe— . rec 

 rchorse. Moxostc 



".orse:--Of the 24 northern 

 ~a aureolum (LeSueur). 



recovered in 1948 all but one were of age group 

 0. The single fish belonged to the 1943 year 

 class (age group V) and measured 17.1 inches 

 in lengfli (Table 18). 



Bigmouth buffalo: --The 1948 collection of 

 rigmouth buffalo included 125 fish less than 8.0 

 inches in length and 10 that ranged between 10.0 

 and 19.9 inches (Table 11). In the 1949 col- 

 lection of 19 fish one was less than 8.0 inches 

 in length. 16 ranged between 9.0 and 12.9, 

 and two measured 18.9 and 20.8 inches. 

 Difficult^" encountered in identifying annuli 

 prevented assignment of individuals to age groujjs . 



Smallmouth buiiaio : - -£:ght smallmouth 

 i^jffalo, Ictiob-js bjbalus (Rafinesque), recovered 

 - -49 rang- r en 9.4 and 14.1 inches and 



all were of age group I . None was observed in 

 1948. 



Comparison with other Mississippi River areas 



Surber (54) found that the important fishes 

 :- "he Mississippi River sloughs of the Tremp- 

 ;_ _i.u, Wisconsin -Winona Minnesota area 

 which were 15 ;:er were the black 



crapr^ ~ : .^^ed, black bullhead, 



birr.- w perch. The northern 



pike, cowfin, and iargemouth bass were the 

 principal carnivorous species but they were 

 present in relatively lower numbers. The popu- 

 ra B were similar but the pumjAin- 



: ...ids. and yellow p)erch were less 



impnrtant . 



30 



