Table 2. -- Species composition of anglers’ catch at Lake Chautauqua in 1941, 1942, 1950, and 1951. 
1 1 Z 2 
1941 1942 
Kind of Fish | [ nak Lh 
Number | Per Cent | Number | Per Cent | Number Per Cent | Number | Per Cent 
Crappie 681 14.4 337 5.0 10,096 27.4 35,462 63.0 
Bluegill 2,043 43.3 3,622 50.5 7,626 20.7 9,335 16.6 
Freshwater drum 55 12 4 0.1 9,459 257 4,274 7.6 
Yellow bass 9 0.2 1,236 E725) || 52222 14.2 2,590 4.6 
Channel catfish 13 0.3 0 0.0 1,205 35.8" 1,206 231 
Largemouth bass 426 9.0 450 6.3 1,348 S137) 1,104 2.0 
White bass 0 0.0 0 0.0 20 0.0 805 1.4 
Bullheads 56 1.2 75 1.0 Tafa 251 483 0.9 
Yellow perch 1,002 AVE) 1,110 15:5 501 1.4 443 0.8 
Sunfishes* 400 8.5 306 4.3 281 0.7 345 0.6 
Other species 34 0.7 4 0.1 293 0.8 242 0.4 
Total number of fish 4,719 100.0 7,164 100.0 36,822 100.0 56,289 100.0 
Fish per fisherman-day 2.8 =<: 4.6 sss Sh 5 aes 4.1 255 
Fish per hour 0.7 --- I 1.0 --- 0.7 --- 0.7 == = 
_ | See Wes east ae | al 
1 Based on Hansen’s (1942) study, which included catch from only one boat yard. 
2 Based on complete creel census of the lake. 
3 Sunfishes other than bluegill. Includes warmouth, green sunfish, and pumpkinseed. 
water stages, fig. 6. 
In general, fishing declined 
during both years when the water level of the lake 
was falling. 
However, fishing for at least one 
species was at its best when the water level was 
either falling or was at a low, stable stage. 
Season 
The 2-year catch data from Lake Chautauqua 
indicate that the species 
composition of the 
anglers’ catches and number of fish caught per 
fisherman-day varied from season to season. 
These catch data are presented by seasons in 
Bele 3 and are illustrated graphically in fig. 7. 
Population Abundance 
A species of fish that is caught readily during 
a given year at Lake Chautauqua may practically 
disappear from the creel within the next 3 years. 
This change in the catch often may be due to a 
tadical change in the abundance of a single dom- 
inant year-class or brood of a single species. 
Dr. David H. Thompson (1941) noted the 
fairly regular occurrence of a dominant brood of 
ctappies in Lake Senachwine, an Illinois River 
bottomland lake near Henry, and the marked 
influence of this brood upon the other fish in the 
lake. He stated: ‘‘A few large crappies produce 
a large brood of young which survive. In subse- 
quent years this dominant brood devours its own 
young as well as the young of other fish. This 
yeatly elimination of spawn and young continues 
until the original dominant brood is so reduced in 
numbers (almost entirely by natural causes) that the 
survivors can no longer gather up all the young 
spawned; then the cycle repeats. In this way the 
ctappie not only produces a cycle in its own kind 
but imposes it on many other non-cannibalistic 
fish. This has a striking effect on both hook-and- 
line and commercial fishing. During part of the 
cycle in Lake Senachwine as many as 99 per cent 
of the black crappies were of catchable size. This 
was followed by a period when there were as few 
as one or two per cent of large fish.”’ 
Fishing Techniques and Factors 
Two years of creel censusing at Lake 
Chautauqua showed that many factors influence 
5 
