In contrast to males, females did not undergo 
a color and pattern change with the approach of 
the spawning season. The most evident morphologi- 
cal changes associated with spring were a marked 
distention of the belly, accompanying the presence 
of maturing ova, and an enlargement of the genital 
papilla (Fig. 3). Enlargement of the papilla in most 
females was evident by February; gross distention of 
the belly preceded spawning by only a few days 
or weeks. 
Small white ova were present in most females 
by October, but in very small females ova did not 
appear until December. Larger yellow ova began 
appearing in December and were present in most 
females by February. Large, maturing orange ova 
appeared in March and April. Just prior to spawning 
the mature ova lost their orange opacity and became 
translucent. The oldest and largest females produced 
the largest numbers of mature ova; the youngest 
and smallest generally produced the fewest. The 
number of mature ova counted in 18 females ranged 
from 28 to 357 (Table 2). For these females the 
relationship between the number of mature ova (F’) 
and the adjusted body weight (W) was F — -27.12 
+ 83.88W, with r — 0.845, and between the number 
of mature ova and the standard length (L) was 
log F = -2.589 + 2.729 log L, with r — 0.691. 
Estimates of the number of eggs laid in aquaria 
by individual females were 50 (by a 57-mm, 3-year- 
old), 50 (by a 62-mm, 3-year-old), 20 (by a 41-mm, 
l-year-old), and 120 (by a 54-mm, 2-year-old). Ma- 
500 e=BIG CREEK 
o=FERGUSON CREEK - 
= 2+8 54 aie 
sy Ol+ | . 
: 4ait Ise e2 
> 
* wr 
o 100 ool elt 
3 240, Se 
S 50 +e asit 
3 ast ge 
= Wepre ee ty a ks 
ro) +, e2+ 
&S I+e oot 
x oo+ OF, e+ = ot el+ 
(Ve) ol+ 
w git o2+ ol e2t 
ac I+ 91442 
<x 10 +87 el+ go lt 
> (ar AF 
fe) 3st ei 
aw ol+ el+t!Qo4 
oO 5 e2+ get elt 
a (as Bet e+ 
O 2+ el+ 
Ww 
= aes SPAWNING 
JULY SEP NOV. JAN. MAR. MAY 
Fig. 5—Monthly variations in ovarian weight relative 
to adjusted body weight of EHtheostoma squamiceps. The 
vertical axis is a logarithmic scale. The number beside each 
dot is the age of the female. The lower five dots for May 
represent postspawning females. 
ture ova averaged 1.6 mm in diameter, were trans- 
lucent, and contained a single oil droplet. 
Spawning and the subsequent absorption of re- 
maining immature ova resulted in a rapid decrease 
in the size of the ovaries. Ovaries of postspawning 
females collected in April and May contained only 
small, white ova and were very small in comparison 
to ovaries of prespawning females collected in March 
and April (Fig. 5). Ovaries increased markedly in 
size between the recovery period and the spawning 
period in the following spring (Fig. 5). The pro- 
portionally largest ovaries (equalling 26.4 percent and 
28.7 percent, respectively, of the adjusted body 
weights of the females) were found in a 2-year-old. 
5l-mm female collected in Big Creek on 9 April 
1971 and in a l-year-old, 37-mm female collected in 
Big Creek on 31 March 1973. Ovary-weight-to-ad- 
justed-weight ratios ranged from 0.091 to 0.287 and 
averaged 0.189 in the 18 females represented in Table 
2. 
Spawning 
E. squamiceps spawned at the study areas from 
late March through May on the undersides of the 
slab rocks (Fig. 6) selected as nesting sites by the 
males. Temperatures at which spottail darters were 
found spawning ranged from 14° to 19° C. These 
temperatures usually prevailed from late March te 
late May, warming from temperatures ranging from 
3° to 10° C in January, February, and early March 
Nests of E. squamiceps were found in Trousdale 
County, Tennessee, on 21 April 1973 and in Todc 
County, Kentucky, on 22 April 1973. Late March 
was the most probable time of spawning for E. 
squamiceps collected at other localities (Table 3). 
Eight spawnings occurred in the laboratory, five 
of which were observed. Four of the spawnings oc- 
curred in the morning hours, one in the afternoon, 
and three during the night or early morning. Aquarium 
temperatures ranged from 19° to 25° C. 
Fig, 6—Egegs of Etheostoma squamiceps on the under 
side of a stone removed from a slab pool in the headwater 
of Big Creek on 22 April 1971. 
