November, 1954 
sent. Rather, there is some _ indication 
that a large bluegill population has a 
depressing effect upon the bass population 
and that interspecific competition may 
exist. 
Bass Spawn Inventory 
‘The idea for an annual inventory of 
schools of largemouth bass fry at Ridge 
Lake originated on May 29, 1941, when 
the first schools of young of that year 
appeared. On this date, three separate 
schools of very small bass fry were lo- 
cated in shallow water close to the inner 
face of the dam; on May 30, what ap- 
peared to be the same schools were found 
in about the same locations, and several 
other schools were found in other parts 
of the lake. 
From May 30 to June 7, 1941, a daily 
search for schools of largemouth bass fry 
was made. wo men in a small rowboat 
moved slowly around the lake shallows, 
one man rowing the boat backwards 
(stern foremost), and the other standing 
up in the stern for maximum vision. In 
this way, it was possible to spot the schools 
in the clear water at distances of about 
25 feet and, at closer range, to make 
rough estimates of the total numbers of 
fry in the schools and to plot on a map 
of the lake the approximate position of 
each school. 
On each succeeding day after May 29, 
the count of schools and the estimate of 
fry increased, until, on June 5, 38 sepa- 
rate schools were counted. (The fry in 
these schools had been spawned from sur- 
vivors of the 100 sexually mature bass 
placed in the lake on April 30 and May 1, 
table 2.) On June 6, 26 schools were 
counted, and, in addition, many small 
groups of fry were seen scattered along 
the shore shelf,* indicating that some of 
the schools had broken up. On June 7, 
larger numbers of fry were observed scat- 
tered along the shore shelf than had been 
seen on the previous day, and fewer 
schools were enumerated. School counts 
were discontinued June 7. 
* A shore shelf is a narrow ledge of earth cut by wave 
action at the water line in parts of the lake where the 
slope of the natural bank is steep. Water over this shelf 
varies between one-half and 2 inches in depth, and small 
ae when over the shelf, are relatively safe from larger 
sh. 
BENNETT: LAaRGEMOUTH Bass IN RIDGE LAKE 
245 
The figure accepted as the estimated 
number of bass fry for the spawning 
season, table 9, was the number for June 
5, 76,000, the highest number recorded 
for any single day of the spawning season. 
This technique of counting schools of 
bass fry and estimating numbers of young 
fish cannot be depended upon to give 
more than a very rough measure of the 
success of spawning at Ridge Lake for 
any given year. It is based on the assump- 
tion that all mature bass inhabiting this 
small body of water reach a condition of 
ripeness and spawn within a period of a 
few days. If eggs were deposited over a 
period longer than 6 or 7 days, the first 
eggs deposited would hatch, the young 
would school, and the schools would 
break up before the last nests of eggs 
were hatched. Once the fry in the schools 
begin to scatter, it is difficult to estimate 
the numbers of young, although a rough 
census of scattered fry can be made at 
Ridge Lake by counting small groups of 
fry along the shore shelf. 
‘The estimates made of the numbers of 
bass fry in the individual schools are 
probably conservative. It was not consid- 
ered desirable to capture and count these 
young fish, and visual estimates of num- 
bers leave much to be desired. In the 
Ridge Lake censusing, no schools of fry 
were estimated to contain more than 3,000 
fish, with the exception of one huge school 
found around the concrete spillway tower 
in 1951. The estimates for most schools 
ranged below 2,000. 
Most schools of bass fry were found 
near shore in water of | to 6 feet in depth. 
A few were found well out from shore 
in the open water of the lake. Ordi- 
narily, the schools of fry were seen fairly 
close to the surface of the water. Occa- 
sionally they were observed to sound and 
disappear from view for several minutes 
before reappearing near the surface. Most 
of the censusing work was done within a 
strip of water extending about 35 feet 
out in the lake from the water edge, and 
it is probable that some schools, ranging 
farther out, were missed. On each day 
of censusing, some schools may have es- 
caped being censused because they were 
submerged. 
The efficiency of censusing may be re- 
duced by turbid waters, floating mats of 
