Table 15. PERCENTAGE SURVIVAL OF SAUGER JUVENILES ACCLIMATED TO
10 - 26 C AND EXPOSED TO HIGHER TEMPERATURES FOR 96 HOURS

Acclimation Temperature,

temperature, Cc TL50,
c 25.0 26.0 27.0 28.0 29.0 30.90 31.0 32.0 ¢
10.1 100 100 12.5 - - - - - 26.6
12.0 - 100 925.0 0 - - - - 26.7
13.9 - - - 87.5 0 12.5 - - 28.4
16.0 - - - 100 12.5 0 - - 28.6
18.3 - - - 100 25.0 0 - - 28.7
19.9 - - - - 100 0 12.5 - 29.5
22.0 - - - - 100 25.0 12.5 - 29.9
23.9 - - - - - 87.5 0 0 30.4
25.8 - - - - - 87.5 0 0 30.4

54


HATCH

PERCENT

Figure 5.

00 ¢

FERTILIZATION TEMPERATURE

sor

60F

6 9 12 15 Is 2i

INCUBATION TEMPERATURE (°C)

The combined effect of fertilization temperature and incubation
temperature on the hatchability of walleye eggs. Each line
represents the percentage hatch of eggs fertilized at one of
six temperatures and incubated at six temperatures, 6, 9, 12,
15, 18, and 21 Cc.

20


RESEARCH REPORTING SERIES

Research reports of the Office of Research and Development,

U.S. Environmental Protection Agency, have been grouped into
five series. These five broad categories were established to
facilitate further development and application of environmental
technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in
related fields. The five series are:

1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research

4... Environmental Monitoring

5. Socioeconomic Environmental Studies

This report has been assigned to the ECOLOGICAL RESEARCH STUDIES
series. This series describes research on the effects of pollution

on humans, plant and animal species, and materials. Prob‘tems

are assessed for their long- and short-term influences. Investigations
include formation, transport, and pathway studies to determine

the fate of pollutants and their effects. This work provides

the technical basis for setting standards to minimize undesirable
changes in living organisms in the aquatic, terrestrial and atmospheric
environments.

This report has been reviewed by the Office of Research and
Development, EPA, and approved for publication. Approval does
not signify that the contents necessarily reflect the views and
policies of the Environmental Protection Agency, nor does mention
of trade names or commercial products constitute endorsement or
recommendation for use.


19.

20.

21.

22.

23.

24.

25.

26.

27.

28.

29.

30.

Allbaugh, C. A., and J. V. Manz. Preliminary Study of the Effects
of Temperature Fluctuations on Developing Walleye Eggs and Fry.
Prog. Fish-Cult. 26(4):175-180, October 1964.

American Public Health Association, American Water Works Associ-
ation, Water Pollution Control Federation. Standard Methods for
the Examination of Water and Wastewater. 13th ed. 1971. 874 p.
Dobie, J., and J. B. Moyle. Methods Used for Investigating Pro-
ductivity of Fish-Rearing Ponds in Minnesota. St. Paul, Minn.
Dept. Conserv., Fish. Res. Unit. Spec. Publ. No. 2. 1962. 62 p.
Fienberg, S. E. The Analysis of Multidimensional Contingency
Tables. Ecology. 51(3):419-433, 1970.

Brett, J. R. Tempering versus Acclimation in the Planting of
Speckled Trout. Trans. Amer. Fish. Soc. 70:397-403, September
1940.

Javaid, M. Y., and J, M. Anderson. Influence of Starvation on
Selected Temperature of Some Salmonids. J. Fish. Res. Bd. Canada
24:1515-1519, July 1967.

Fry, F. E. J. Effects of the Environment on Animal Activity.
Univ. of Toronto Studies, Biol. Ser. No. 55. Publ. Ont. Fish.
Res. Lab. No. 68. 1947. 62 p.

Brett, J. R. Some Principles in the Thermal Requirements of
Fishes. Quart. Rev. Biol. 31(2):75-87, 1956.

Fry, F. E. J. The Summer Migration of Cisco, Leucichthys artedi
(Le Sueur), in Lake Nipissing, Ontario. Univ. of Toronto Studies,
Biol. Ser. No. 44. 1937. 91 p.

Doudoroff, P. Reactions of Marine Fishes to Temperature Gradients.
Biol. Bull. 75:494-509, 1938.

Proffitt, M. A. Effects of Heated Discharge upon Aquatic Resources

of White River at Petersburg, Indiana. Water Resources Res. Center.
Rept. of Invest. No. 3. 1969. 101 p.
Merriman, D. The Calefaction of a River. Sci. Amer. 222(5) :42-52,

1970.

63


eggs were taken at a temperature as high as 17.2 C, they were poor
as a rule. Also good hatches have occurred with walleye eggs
subjected to as low a temperature as where slush ice had formed in

the water.

Dendy, Jack S. Descriptors

1948. Predicting depth distribution of fish WALLEYE
in three TVA storage type reservoirs. SAUGER
Trans. Amer. Fish. Soc. 75(1945): TENNESSEE
65-71. DISTRIBUTION

In TVA reservoirs the depth distribution of walleyes and saugers
were predictable on a weekly basis based on the relation of tempera-
ture and dissolved 0, to the distribution of fish in gill nets
during the years 1943, 1944, and 1945. Thus it can be predicted
that in the latter part of July, saugers were most abundant at a
depth where the temperature was about 18.3 C and walleyes were most
abundant at a depth where the temperature was about 25.0 C.

Derback, B. Descriptors

1947. The adverse effect of cold weather WALLEYE
upon the successful reproduction of MANITOBA
pickerel, Stizostedion vitreum, at SPAWN

Hemming Lake, Manitoba, in 1942.

Can. Fish-Cult. 2(1): 22-23.
The author believed that there seemed to be a strong correlation
between spawning activity and water temperature. In Hemming Lake,
Manitoba, when walleyes ran up the creek to spawn the temperature
was 5.6 C. The first walleye eggs were observed 4 days later at
6.1 C. Then a period of cold weather set in to lower the tempera-
ture the following week to 5.0 C, and as a result the walleye
moved back downstream into the lake. Resulting catches of walleye
in late June showed that the females were resorbing their eggs.

74


oT

2
3S
m

VIEWS

>
-

a

0.3CM 1.0.

2.5CM -2.5CM a5 CM ———>4

k—3.8CM——>|

TOP
VIEW

BOTTOM
VIEW

Figure 3. Diagram of the incubation cylinder showing the top, bottom, and side views.


SECTION XV

APPENDIX B

AN ANNOTATED BIBLIOGRAPHY OF THERMAL EFFECTS
ON THE NORTH AMERICAN STIZOSTEDION SPECIES

69


Le

Table 6. THE EFFECT OF 6 DIFFERENT TEMPERATURES ON WALLEYE EGGS AND FRY af HELD AT A CONSTANT
TEMPERATURE DURING FERTILIZATION, INCUBATION, AND AFTER HATCHING

Mean Survival Survival

Tempera—- Egg Abnormal Days to Days to Days to size at of sac to juvenile
ture, survival?! fry, first median completion hatch, fry sc stage av

Cc & 4 hatch hatch hatch mm. Zz z
6.0 84.0 1.0 30 34 49 6.0 0 0
8.9 66.5 ~ 3.8 23 27 31 7.3 78 0
12.0 61.5 3.3 12 15 18 7.8 88 0
15.0 15.0 1.0 8 10 11 7.2 95 0
18.1 32.0 15.0 6 7 8 7.2 97 1
20.9 0.0 18.0 se! se! ee! 6.62! gat! ac!

al Fry data was determined from 100 hatched fry that were taken at random from the total hatch at
each temperature. Abnormal fry were not included.

z 200 eggs tested at each temperature.

Yy The sac fry stage was determined to be from hatch to the disappearance of the yolk sac.

2 Fish were denoted as juveniles when they reached a length of 40 m.

=" Data obtained from fry hatched from eggs incubated at 21 C but fertilized at 9 and 12 C.


SECTION VII

EFFECT OF A SUDDEN TEMPERATURE CHANGE ON WALLEYE

EXPERIMENTAL DESIGN

Tests were performed on walleye fry and juveniles to determine the
effect of a sudden temperature change on survival. Fry were slowly
removed with a glass tube from their respective chambers to a beaker
with the same temperature water to which they were acclimated. Then
they were transferred to another fry chamber with a higher or lower
temperature by lowering the beaker to water level and pouring the fry
slowly out into the other chamber. A control was run with each test
when the fish went through the same transfer process from one chamber
to another but were not exposed to a temperature change. The sur-
vival of the control fry was corrected to 100% and the survival in the
treatments was corrected dccordingly. Walleye juveniles were subjected
to a similar transfer process but a net was used for capture and a
larger container was used to transfer the fish from the acclimation
chamber to the test chamber.

Temperatures did not fluctuate more than + 0.1 C and the pouring process
at the start of the test did not lower or raise the initial test tem-

perature more than 0.1 C.

Tests were done over a 72-hour period for fry and 96-hour period for
juveniles. The 72-hour period for fry tests was used to eliminate

starvation as a factor of mortality.

FRY TESTS

Sudden temperature changes were performed on walleye fry hatched and
acclimated at 6, 11, and 21 C. The fry were subjected to both an up-

34


water more than older and larger individuals. Kelso? reported 20 C

as the optimum temperature for growth of walleyes, age II-VI. Hile and
Juday?” reported the preferred temperature of adult walleyes to be
20.6 C during summer months, and Ferguson?? reported the preferred
temperature of adult walleyes to be 22.7-23.2 C.

Walleye fry and juveniles acclimated to different temperatures were
exposed to a sudden temperature change without severe mortality. It
is apparent that the extent of temperature change is less important
than the absolute test temperature. If the temperature change is
within the upper or lower tolerance limits, little or no mortality
will occur. Mortality of fry from temperature change occurred only
when fry hatched at 11 C were transferred to 6 C, a net change of -5 C,
and fry hatched at 21 C were transferred to 6 C, a change of -15 C.
It appears that 6 C is a lethal temperature for fry hatched at 11 and
21 C, since fry hatched at 21 C and transferred to a temperature of
11 C, a change of -10 C, did not incur high mortality.

Juvenile walleyes exposed to a sudden temperature change showed a

mortality only in fish acclimated to 25 C and dropped to 8 C, a change
of -17 C, where loss was 30%. This suggests that 8 C is probably

close to the lower lethal temperature of juveniles acclimated to 25 C.
Tests done with saugers were upward shifts toward lethal temperatures
so the effect of drops in temperature were not assessed. However, the
extent of a sudden change in temperature did not harm fish until upper

lethal temperature was approached.

The upper lethal temperatures determined for walleye and sauger ju-
veniles can be applied to juveniles only. The upper lethal tempera-
ture for larger fish may be slightly lower.

It is apparent from the results of the tests described herein that

59


o¢€

Table 7. GROWTH OF WALLEYE JUVENILES FOR 28 DAYS AT DIFFERENT TEMPERATURES

Mean length Mean weight Specific

Temper- at start of Increase Increase at start of Increase Increase growth
ature, test, in length, in length, test, in weight, in weight, rate, Survival,

Cc mn mm. vA a gz & Z/ day vA
16.3 65.1 23.1 35.5 2.00 3.13 156.5 3.371 100
21.1 65.0 39.0 60.0 1.91 6.53 341.9 5.325 100
25.2 63.7 44.4 69.7 1.81 7.77 429.3 5.950 100
18.1 84.2 25.8 30.6 4.30 6.48 150.7 3.286 100
20.2 84.6 31.6 37.4 4.59 8.13 177.1 3.639 100
22.1 85.5 36.1 42.2 4.62 9.58 207.4 4.007 100
23.9 85.7 32.6 38.0 4.71 7.79 165.4 3.482 80
26.0 85.2 29.3 34.4 4.42 6.66 150.7 3.286 80

28.0 86.5 23.7 27.4 4.94 5.15 104.3 2.546 60



10.

il.

12.

13.

14.

16.

17.

18.

Payne, N. R. The Life History of the Walleye, Stizostedion
vitreum vitreum (Mitchill), in the Bay of Quinte. M.A. Thesis,
Univ. of Toronto, Toronto. 1964. 40 p.

Priegel, G. R. Reproduction and Early Life History of the Walleye
in the Lake Winnebago Region. Madison, Wisc. Dept. Nat. Res.
Tech. Bull. 45. 1970. 105 p.

Rawson, D. S. The Life History and Ecology of the Yellow Walleye,
Stizostedion vitreum, in Lac la Ronge, Saskatchewan. Trans. Amer.
Fish. Soc. 86(1956) :15-37, 1957.

Schumann, G. 0. The Effect of Abnormal Temperatures on the Spawning
and Developmental Success of Eggs from the North American Walleye.
Transl. by D. N. Busch, U. S. Bur. Comm. Fish., Sandusky, Ohio.
Osterreichs Fischerei. 5:85-87, May 1964.

Spinner, J. Environmental Effect on the Spawning Run of Northern
Pike and Walleye in the Upper Mississippi River. Proc. North
Central Warm Water Fish Culture Workshop, Ames, Iowa Coop. Fish.
Unit, February 15-16, 1968. p. 9-12.

Carufel, L. H. Life History of Saugers in Garrison Reservoir. J.
Wildl. Manag. 27(3):450-456, July 1963.

Nelson, W. R. Reproduction and Early Life History of Sauger,
Stizostedion canadense, in Lewis and Clark Lake. Trans. Amer.
Fish. Soc. 97(2):159-166, April 1968.

Priegel, G. R. The Lake Winnebago Sauger--Age, Growth, Reproduction,
Food Habits and Early Life History. Madison, Wisc. Dept. Nat. Res.
Tech. Bull. 43. 1969. 63 p.

Priegel, G. R. Lake Winnebago Cousins. Wisc. Conserv. Bull.
33(2) 224-25, 1968.

Steucke, E. W. Optimum Temperatures for Hatching Northern Pike
and Walleye Eggs. Proc. North Central Warm-Water Fish Culture
Workshop, Ames, Iowa Coop. Fish. Unit, February 15-16, 1968.

p- 32-34.

62


SECTION VIII
WALLEYE UPPER LETHAL TEMPERATURE

EXPERIMENTAL DESIGN

Upper lethal temperature tests were conducted on juvenile walleyes
which had been subjected to a wide range of acclimation temperatures.
These fish had a mean length of 115 mm. All fish were acclimated to-
gether in a large holding tank for 2 weeks. They were then placed in
three 25-liter flow-through chambers at- their acclimation temperature
in groups of ten for 2 days before each test began. Temperatures were
held constant throughout each acclimation period (S.D. = 0.07). Ac-
cording to Brett”? the rate of temperature change over a period of a
few hours will not greatly affect the thermal tolerance limit since

the acclimation to changing temperatures requires several days. There-
fore for these tests the temperatures were raised to the experimental
temperatures at a rate of 3-4 C/hour. The test began at the end of the
temperature rise. Test temperatures did not fluctuate greatly (S.D. =
0.11). Fish were not fed for 96 hours prior to testing since feeding
could influence the upper lethal temperatures. Javaid and Anderson2#
found that starvation influences the selected temperatures of salmonids.

LETHAL TESTS

Upper lethal temperatures of TL50s were graphically determined for wall-
eye juveniles acclimated to temperatures ranging from 8 to 26 C by 2 C
intervals (Table 11). Fish were tested for 96 hours only since mortal-
ity occurred mostly within the first 12 hours of the test. The upper
lethal temperature is the incipient lethal temperature which is defined
by Fry? as the temperature at which 50% or more of the fish died.

The upper lethal temperature increased as the acclimation temperature
increased. From an acclimation temperature of 8 to 14 C the TL50 in-

40


24,

25.

of water temperature on the rate of embryo development. But he
observed that most rapid embryo development and short incubation
periods were associated with high daytime water temperatures and
high minimum water temperatures. Egg survival was best in years
of warmer water temperatures and shorter incubation periods. Also
it was stated that egg mortality, especially as associated with
unusually cold water during the incubation period, may be an im-
portant factor in the establishment of year classes.

Johnson, Fritz H. Descriptors
1966. Environmental and species associations WALLEYE
of the walleye in Lake Winnibigoshish MINNESOTA
and connected waters, including ob- DISTRIBUTION

servations on food habits and predator~

prey relationships. Minn. Dept. Conserv.

Invest. Rep. 301, 34 p.
Walleye distribution in Lake Winnibigoshish, Minnesota was not
influenced by bottom temperatures that ranged between 13.3 C and
20.6 C, but the fish extended their range into deeper, cooler
waters when the surface temperatures rose above 21.1 C. Tol-
erance for water temperatures above 21.1 C appeared to decrease as
age and size of the fish increased. When late fall water tem-
peratures on the shoals ranged from 6.7-8.9 C, the fish were no
longer in shore. This indicates that there could be a minimum
fall temperature threshold below which the fish seek deeper,

warmer water.

Kelso, John R. M. Descriptors
1972. Conversion, maintenance, and assimilation WALLEYE
for walleye, Stizostedion vitreum vitreum, MANITOBA
as affected by size, diet, and tempera-— GROWTH
ture. J. Fish. Res. Bd. Canada 29:
1181-1192.
Walleyes of age II to VI were tested for growth and food conversion

82


SECTION IT
RECOMMENDATIONS

Recommendations for thermal criteria for saugers and walleyes based
on the laboratory studies reported here indicate different levels
for spawning and incubation and for later stages. For the period
of fertilization and incubation temperature should not exceed 15 C.
During the period of early fry development temperature should not
exceed 18-21 C. Summer temperature should not exceed a weekly
average of 24 C or a maximum of 27 C to insure sustained growth and

survival of juveniles.


CONTENTS

Abstract

List of Figures
List of Tables

Acknowledgments

Sections

Tt Conclusions

II Recommendations

III Introduction

Iv Materials and Methods

v Walleye Egg and Fry Survival

VI Growth of Juvenile Walleyes

VII Effect of a Sudden Temperature Change on Walleye
VIII Walleye Upper Lethal Temperature

Ix Sauger Egg and Fry Survival

x Growth of Juvenile Saugers

XI Upper Lethal Temperatures for Sauger Juveniles
XII Discussion

XIII References

XIV Appendix A - Statistical Tables

XV Appendix B - Annotated Bibliography

ili.

an Pwr

7
29
34
40
46
50
52
57
61
65
69


C when juveniles acclimated to 25 C were exposed to 8 C (Table 9).
Sublethal response was observed with a change of ~-17 C. Initially all
fish lost their equilibrium and then swam belly up for the first 30
min of the test. Thereafter the survivors (70%) adjusted to the cooler
temperature but remained inactive and did not feed. Sublethal effects
but no mortality were observed with a temperature change of -13 C when
fish acclimated to 21 C were exposed to a temperature of 8 C. Some

of the fish lost their equilibrium with this temperature drop. Initially
30% of the juveniles swam belly up but adjusted after 10 min. All the
fish were slightly inactive and only a few accepted food. No mortality
or abnormal behavior was observed with fish exposed to a -9 to -4C
temperature change. Percentage survival and test temperatures are
indicated on Table 9.

Juveniles acclimated to 16 and 21 C were subjected to temperatures as
high as 12 C above the acclimation temperature (Table 10). Fish
acclimated to 21 C were exposed to temperature changes of +4 and +7 C

but no mortality or abnormal behavior was observed.

37


Appendix A, Table 3
DUMMY VARIABLES REPRESENTING FERTILIZATION TEMPERATURE
IN THE REGRESSION EQUATIONS FOR DETERMINING
THE SIZE OF WALLEYE FRY AT HATCH
Variables Used in Equation for Incubation Temperature of 18 C

Nominal
fertilization
temperature, Dummy variables
¢ 4 % Xs;
1 tt) 0
0 1 0
12 0 0 1
18 -1 -1 -1

68


14.

15.

Ellis, D. V., and M. A. Giles Descriptors
1965. The spawning behavior of the walleye, WALLEYE
Stizostedion vitreum (Mitchill). MANITOBA

Trans. Amer. Fish. Soc. 94(4): 358-362. SPAWN
Spawning activity and courtship was studied in Manitoba. Walleyes
have a diel behavioral cycle, low activity in day-time and court-
ship activity in the evening. The water temperature during the
spawning period ranged from 6.7-13.0 C.

Eschmeyer, Paul H. Descriptors

1950. The life history of the walleye WALLEYE
Stizostedion vitreum vitreum (Mitchill), MICHIGAN
in Michigan. Mich. Dept. Conserv., SPAWN

Inst. Fish. Res., Bull. 3, 99 p.
Walleye spawning was observed in Lake Gogebic, Michigan in the years
1941, 1942, 1947, and in the Muskegon River in 1936, 1944, 1947,
and 1948. The results were:

Start of Peak of
Location spawning run spawning run

Lake Gogebic (1941) 3.9 C¢ 8.3
Lake Gogebic (1942) 4.4 7.8-8.9 C
Lake Gogebic (1947) 1.1¢ -—
Muskegon R. (1936) -- 4.4-5.6 C
Muskegon R. (1944) - 3.3C
Muskegon R. (1947) - 4.4C
Muskegon R. (1948) -- 6.7C

The peak of the spawning run in Lake Gogebic occurs when shoal
temperatures range from 7.2-10.0 C. In the Muskegon River the
peak of the spawning run occurs when the temperatures range from
4.4-6.7 C.

77


EPA-660/3-75-017
MAY 1975

Ecological Research Series



ABSTRACT

Temperature effects on the early life history stages of the walleye
(Stizostedion vitreum vitreum (Mitchill)) and sauger (Stizostedion
canadense (Smith)) were examined. Walleye eggs and fry were exposed

to six temperatures (6-21 C) for effects on fertilization, incubation,
and fry survival. Mature sauger were held and eggs were fertilized

at four temperatures (9-18 C). Both species were incubated at 6-21 C.
Sauger fry survival was also tested at 6-21 C. Optimum fertilization
temperatures were 6-12 C for walleye and 9-15 C for sauger. Optimum
incubation temperatures were 12-15 C for both walleye and sauger. A
sharp drop or rise in temperature had no great effect on walleye fry
and juvenile survival except when the upper lethal or lower lethal
temperature was approached. Optimum temperature for juvenile walleye
and sauger growth was 22 C. Upper lethal temperatures for walleye
juveniles were determined for acclimation temperatures at 2 C intervals
between 8-26 C. The upper lethal temperature of walleye juveniles

was 27.0-31.6 C, depending on acclimation. The upper lethal tempera-
ture of sauger acclimated to 10-26 C was 26.6-30.4 C. There was little
temperature difference (1-2 C) between 100% survival and no survival.

This report was submitted in fulfillment of Project Number 18050 PAB,
Contract Number R800704, by the Department of Entomology, Fisheries,
and Wildlife, University of Minnesota, under the sponsorship of the
Environmental Protection Agency. Work was completed as of November
1973.

ii


SZ

Table 5. SIZE OF WALLEYE FRY (MILLIMETERS) AT HATCH CALCULATED FROM THE REGRESSION EQUATIONS
Number of Measurements in Parentheses
Incubation Fertilization temperature, Mean number
temperature, ¢ of days
c 6 9 12 15 18 21 to hatch
6 6.06(16) 6.03(11) 5.81(12)  5.68(2) 5.75(6) 5.86(1) 37.8
9 7.09(13) 7.05(13) 6.55(11) 6.35(7) 7.29(11) —6.75(4) 25.8
12 7.66(12) 7.72(8) 7.77(12) —-7.13(3) 7.33(6) 7.44(5) 15.4
15 7.53(9) 7.65(11) =7.90(9) 7.26(5) 7.45(7) 7.12(1) 10.4
18 7.18(8) 7.11(8) 7.39(5) - 7.22(6) - 7.3



28.

29.

Nelson, William R., Norman R. Hines, and Descriptors
Lance G. Beckman WALLEYE
1965. Artificial propagation of saugers and SAUGER
hybridization with walleyes. Prog. S. DAKOTA
Fish-Cult. 24(4): 216-218. INCUBATION

Walleye and sauger brood stock were collected in the Missouri
River between April 15-29, when the spawning run started. The
temperature during the collection period ranged from 3.9 C to
8.3 C. The fish were placed in ponds which had a temperature
range from 6.1 C to 12.8 C and were allowed to ripen both nor-
mally and with carp pituitary injections. Fertilized eggs were
then placed in hatching jars where water temperatures ranged
from 10.0 C to 12.2 C when the eggs began hatching. Walleye eggs
reached the eyed stage in 8 days and began hatching in 13 days.
Sauger eggs began hatching in 9 days and continued through the
14th day.

Niemuth, Wallace, Warren Churchill, and Descriptors
Thomas Wirth WALLEYE
1959. The walleye, its life history, ecology, WISCONSIN
and management. Wisc. Conserv. Dept. SPAWN
Pub. 227, 14 p. INCUBATION

The walleye spawning migration begins in Wisconsin when the water
temperature reaches 3.3-6.7 C. Spawning reaches a peak when
temperatures are 8.9-10.0 C, although spawning has been observed
between the temperatures of 6.1 and 17.2 C. Walleye eggs hatch
in 26 days when the water temperature is 4.4 C, 21 days when the
water temperature is from 10.0-12.8 C, and in 7 days with a mean
water temperature of 13.9 C.

84


19.

Hassler, William W. Descriptors

1955. The influence of certain environmental SAUGER
factors on the growth of Norris Reser- TENNESSEE
voir sauger, Stizostedion canadense GROWTH

canadense (Smith). Proc. Southeastern
Ass. Game Fish Comm. Mtg., p. 111-119.

First year growth rates of sauger during a 13-year span were
correlated with:

1. Water temperature data for 13 years. Water temperatures
of 15.6 C at a depth of 0.5 feet were used to demarcate
the length of the sauger growing season.

2. Time in days between 10.0 C and 15.6 C at a depth of 0.5
feet.

3. Air temperature, both mean monthly and mean annual.

Growth rates were significantly correlated with water temperature
with a correlation coefficient of .69. There was an inverse
relationship between degree days and growth rates with a corre-
lation coefficient of -.51. There was no correlation between air
temperature and growth rates.

It was suggested that there are three possible ways in which
sauger growth may be affected inversely during the spring:

1. There is a lower metabolic rate during a prolonged period
of time if the water temperature increases slowly.

2. A greater survival of sauger fry and fingerlings may occur
during the years when temperature increases slowly. This
would result in a greater population density which in turn
could be a limiting factor on growth.

3. Because forage fish spawn later than sauger (10.0 C for
sauger and 15.6 C for forage fish), there would be a lower
rate of growth if the lake warms up slowly. The period of
planktonic feeding would be prolonged since forage fish
would be available at a later time than usual.

79


produce an oxygen concentration of 5 mg/liter or greater.

The temperature in each head tank was controlled with a bimetal thermo-
regulator wired through a relay to two 1000-watt immersion heaters.
They maintained temperatures in the experimental chambers within a
range of + 0.2-0.3 C (SD = 0.26) of the desired temperature of each
experiment.

After temperature adjustment water was fed to a set of experimental
incubation, fry, and juvenile test chambers. Water from the head tank
flowed by gravity through 3/4 inch polyvinyl chloride pipe to each
set of chambers and then through tygon tubing to individual chambers
(Figure 1).

Eggs were tested in incubation chambers consisting of acrylic tubes
10 cm long, with an inside diameter of 3.8 cm. Inside the cylinder,
5 cm from the top, the eggs lay on #656 Nitex screen where water
flowed past at an average rate of 325 ml/min (range, 200-425). The
incubation cylinders were submerged in small, 13.5 x 10.5 x 20 cn,
cases with three glass sides and one of #656 Nitex screen. These
cases were placed in larger aquaria so that the cylinders were sub-
merged but not the top of the cases. This arrangement allowed the
fry to swim out of the incubation cylinders and be removed to larger
fry chambers. Incubation chambers are shown in Figures 2 and 3.

'
Fry chambers were set up in a flow-through system consisting of glass
aquaria 25 x 25 x 50 cm, constructed of double strength window glass
and silicone adhesive (General Electric Silicone Seal). An outlet
tube (1/2 inch OD) set 20 cm from the bottom maintained a volume of
25 liters in the chamber. The flow rate through the aquaria was about
1 liter/min (+ 100 ml).


Times to first hatch, median hatch, and total hatch were 37, 45, and
58 days at 6 C; 22, 28, and 35 days at 9 C; 12, 16, and 21 days at
12 C; 8, 10, and 13 days at 15 C; 7, 8, and 10 days at 18 C; and 5,
6, and 8 days at 21C. Time to first hatch, median hatch, and total
hatch was longest at the lowest temperature (6 C) and decreased to a
minimum of 5 days to first hatch, 6 days to median hatch, and 8 days
to total hatch at the highest temperature (21 C).

The mean size of the fry at hatch was 4.77, 5.76, 5.84, 5.58, 5.64,
and 5.59 at 6, 9, 12, 15, 18, and 21 C, respectively. The size of
the fry was least at 6 C (4.77 mm) but did not vary greatly at the
other temperatures.

The survival of sauger fry from hatch to the disappearance of the yolk
sac was high for all temperatures except 6 C. At 6 C the fry did not
lose the yolk sac before dying although they survived about 30 days.

The fry survival at the temperature of 9 to 21 C ranged from 75 - 92%.

Total survival of sauger fry from hatch to the juvenile stage was low
at all temperatures. At 21 C 8% of the fry survived, at 18 C 1% sur-
vived, and at 6-15 C all died before the juvenile stage. All fry were
fed large quantities of plankton. Most of the fry at the higher tem-
peratures fed well while fry at the lower temperatures did not accept
food. Fry mortality was observed to be caused by starvation, since
temperature was the trigger mechanism to feeding for fry held in
captivity under laboratory conditions.

49


WALLEYE (STIZOSTEDION VITREUM VITREUM)

1
9
15
22
29
36

6
28

BLUE PIKE (STIZOSTEDION VITREUM GLAUCUM)

3

2
10
16
23
30
37

SAUGER

8
33

10

INDEX

4 5 7
11 12 13
17 18 20
24 25 26
31 32 33
38 39 40

(STIZOSTEDION CANADENSE)

10 16 19
34 37 42

91

14
21
28
35
41

27


INTRODUCTION

The literature on thermal effects on the North American Stizo-
stedion species was compiled and presented in annotated form. Only
temperature~related literature was reviewed. Temperature data reported
in the original literature as Fahrenheit has been changed to Centigrade.
The annotated bibliography lists the effects of temperature on the wall-
eye, sauger, and blue pike. The listing of unpublished data is incom-
plete in university reports as well as unpublished reports of state,
provincial, and federal agencies.

Each reference is cross-indexed by species, geographical location,
and additional subject headings. Listed numbers in the index refer
to the numbers on publications in the main body of the citation list.

70


GROWTH AT 18-28 C (1972)

In 1972 walleye juvenile growth was tested at six temperatures, 18,

20, 22, 24, 26, and 28 C (Table 7). The mean weight of these fish at
the beginning of the test was 4.30 g at 18 C, 4.59 g at 20 C, 4.62 g
at 22 C, 4.71 g at 24 C, 4.42 g at 26 C, and 4.94 g at 28 C. Maximum
growth was at 22 C where the juveniles increased 42.2% in length and
207.4% in weight and had a corresponding specific growth rate of 4.007.
Minimum growth was obtained at 28 C. At this temperature the juveniles
tained 27.4% in length, 104.3% in weight and had a specific growth
rate of 2.546. At 18 and 26 C the growth rate was identical. Although
the percentage gain in length at 18 C (30.6%) differed from 26 C
(34.4%), the specific growth rate was 3.286 and the percentage gain in
weight was 150.7% for both temperatures. The rate of increase in the
specific growth rate between 18 and 22 C was the same as the rate of
decrease between 22 and 26 C.

A multiple regression analysis was done to determine the temperature
where the asymptote of the growth curve occurs. The regression equa-
tion describing the growth of walleye juveniles of 1972 at different
temperatures was determined to be

Y = -50.917 + 5.3740X - e121x (6)

where Y
x
This equation has an Rr? of 79.3%, which indicates that the resulting
binomial curve reduced the variability in the data by 70.3%. Curves
for both the actual data and the predicted data are shown in Figure 6.

weight increase in grams

temperature in C.

31


29)

8

Nn
~“

TEMPERATURE (°C)

Nn
2)

8 0 (2 14 16 18 20 22 24 26

ACCLIMATION TEMPERATURE (°C)

Figure 7. TL10 and TL90 levels of walleye juveniles
exposed to upper lethal temperatures. TL10 and TL90
were at 10 and 90% survival plotted on arithmetic
paper.

43


8Y

Table 13. THE EFFECT OF SIX CONSTANT TEMPERATURES ON SAUGER EGGS AND Frv3/

Time to Time to Time to Mean Survival Survival
Tempera- Egg Abnormal first median completion ‘size at of sac to juvenile
ture, survival sb fry, hatch, hatch, hatch, hatch, fry, stage a
Cc % a days days days mm a ’
6.0 - 2.08/ 378! ase! see! 4.778! @/ e/
8.9 72.2 2.0 22 28 35 5.76 92 0
12.0 32.0 3.5 12 16 21 5.84 86 0
15.0 73.5 18.0 8 10 13 5,58 75 0
18.1 44.5 3.3 7 8 lo 5.64 90 1
20.9 - 23.02! se! oe/ e/ 559°! ase! e/

al Fry data were determined from 100 hatched fry taken at random from the total hatch at each
b/ temperature. Abnormal fry were not included.

e/ Two hundred eggs were tested at each temperature.
a/ Sac fry stage was determined to be from hatch to the disappearance of the yolk sac.

e/ Fish were determined to be juveniles when they reached a length of 40 mn,

.Data from fry fertilized at 9-18 C but incubated at 6 and 21.


SECTION IX
SAUGER EGG AND FRY SURVIVAL

EXPERIMENTAL DESIGN

Sauger adults were acclimated to four temperatures, 9, 12, 15, and
18 C. After the adults became ripe they were stripped and the eggs
were fertilized at the same four temperatures. After fertilization
the eggs were incubated in the same manner and at the same six tem-
peratures (6-21 C) as the walleye eggs (Figure 4). The fry hatched
at these temperatures were carried through to juveniles at the same
temperatures to determine fry survival to yolk sac absorbtion and to
the juvenile stage. Replicates were combined in the final analysis
since there was no significant difference between replicates at the
-05 level.

HATCHABILITY OF SAUGER EGGS’

Effect of Fertilization Temperature on Hatch

Sauger eggs were tested to determine the effect of various temperatures
on fertilization, incubation, and egg survival (Figure 8, Table 12).
Eggs were fertilized at 9, 12, 15, and 18 C and the group of eggs
fertilized at each temperature was incubated at six temperatures; 6,

9, 12, 15, 18 and 21 ¢.

The lowest fertilization temperature (9C) resulted in the highest per-
centage hatch for each of the incubation temperatures except at 12 C
where eggs fertilized at 15 C had a slightly higher percentage hatch
(77.0%) than at 9 C (75.7%). The percentage hatch decreased as the
fertilization temperature increased. Lowest egg survival resulted from
a fertilization temperature of 12 C but these eggs may have had low sur-
vival from similar reasons noted for walleye eggs fertilized at 15 C.

44


7.

In the Bobcaygeon region of the Kawantha Lakes the heavy run of
spawning walleyes occurred when river temperatures were at 4.4-
7.2 C. The greatest spawning activity occurred at temperatures
between 6.1 and 8.3 C. Spawning appeared to be completed when the
water temperature reached 10.0 C. In all cases, the heavy spawning
run commenced at a temperature 1.7-2.2 C lower than the actual
spawning temperature.

Butler, G.E. Descriptors

1937. Artificial propagation of walleyed WALLEYE
pike. Trans. Amer. Fish. Soc. MANITOBA
66(1936): 277-278. INCUBATION

It was reported that strong winds stirred up the mud from the
creek that fed water to the walleye hatchery and subsequently
raised the temperature to 18.3-21.1 C. The combination of mud
and high temperatures caused the mortality of a large number of

eggs.

Carufel, Louis H. Descriptors

1963. Life history of saugers in Garrison SAUGER
Reservoir. J. Wildl. Manag. 27(3): N. DAKOTA
450-456. SPAWN

The 1960 spawning season for saugers in Garrison Reservoir ran
from May 2 - June 25, where the height of the season was from May
8-28. Water temperatures ranged from 3.9-11.7 C.

Cobb, Eben W. Descriptors
1923. Pike-perch propagation in northern WALLEYE
Minnesota. Trans. Amer. Fish. Soc. MINNESOTA
53: 95-105. SPAWN
INCUBATION

It was decided that the best temperatures for taking walleye eggs
range from 7.2-10.0 C, preferably between 7.8-8.9 C. Although

73


26.

27.

at different temperatures. Greatest walleye weight gain occurred
at a temperature of 20 C. Kj; conversion weight gained per unit
time to ration size, was 0.143 at 20 C, 0.127 at 16 C, and 0.136
at 12 C. At 4, 8, and 12 C the maintenance requirement varied
slightly (33.25-45.70 cal/g/week). At a cycled temperature (16-
8 C) for a period of 4 weeks the requirement was 40.2 mg/g/week.
Between 20 C and 32 C the amount of energy consumed by the fish
was similar.

Kennedy, William A. Descriptors
No date (approx. 1935). Report on the WALLEYE
migration of pickerel due to tem- ONTARIO
perature changes. Unpub. MS, 15 p. DISTRIBUTION
In Univ. Toronto, Great Lakes Inst.
Libr.

It was observed that as the water warmed, walleyes in Lake
Nipissing, Ontario moved to deeper waters, the larger fish
migrating first. It was found that the walleyes do not penetrate

the thermocline which would entail a sudden change of temperature.

Nelson, William R. Descriptors

1968. Reproduction and early life history of SAUGER
sauger, Stizostedion canadense, in S. DAKOTA
Lewis and Clark Lake. Trans. Amer. SPAWN
Fish. Soc. 97(2): 159-166. INCUBATION

.Sauger in Lewis and Clark Lake spawn upstream near the Fort Ran-

dall Dam when water temperatures reach 5.6-6.1 C. The incubation
period at an average water temperature of 8.3 C was approximately
21 days.

83


Table 9. EFFECTS OF SUDDEN TEMPERATURE CHANGE ON WALLEYE JUVENILES
EXPOSED BELOW THEIR ACCLIMATION TEMPERATURE - 96 HOURS

Acclimation Test. Temperature

Number temperature, temperature, change, Survival

of fish Cc Cc c ’
20 16.0 12.1 - 3.9 100
20 21.0 16.0 - 5.0 100
20 16.0 8.1 -7.9 100
20 21.0 12.1 - 8.9 100
20 25.0 16.0 - 9.0 100
20 21.0 8.1 -12.9 100
20 25.0 8.1 -16.9 70

38


EPA-660/3-75-017
MAY 1975

TEMPERATURE EFFECTS ON EGGS AND FRY OF PERCOID FISHES

By

Lloyd L. Smith, Jr.
Walter M. Koenst
Department of Entomology, Fisheries, and Wildlife
University of Minnesota
St. Paul, Minnesota 55101

Grant No. R800704
Project 18050 PAB
Program Element 1BA021

Project Officer

Kenneth E, H, Hokanson
National Water Quality Laboratory
National Environmental Research Center
Monticello Field Station
Box 500
Monticello, Minnesota 55362

NATIONAL ENVIRONMENTAL RESEARCH CENTER
OFFICE OF RESEARCH AND DEVELOPMENT
U. S. ENVIRONMENTAL PROTECTION AGENCY
CORVALLIS, OREGON 97330

le intendent of Documents, U.S. Government Printing Office
For sale By tip Superintengeat 3h ps Booch No. Ose 001-0108


SECTION XIII

REFERENCES

Bradshaw, J., and B. S. Muir. The 1960 Spawning Run of Yellow
Pickerel at Bobcaygeon in Relation to Water Temperature. Ontario
Dept. Lands & Forests, Southeastern Region, Spec. Fish. Wildl.
Bull. 3. 1960. p. 4-6.

Cobb, E. W. Pike-Perch Propagation in Northern Minnesota. Trans.
Amer. Fish. Soc. 53:95-105, September 1923.

Eddy, S., and T. Surber. Northern Fishes with Special Reference
to the Upper Mississippi Valley. Minneapolis, Univ. of Minnesota
Press. 1943. 276 p.

Ellis, D. V., and M. A. Giles. The Spawning Behavior of the Walleye,

Stizostedion vitreum (Mitchill). Trans. Amer. Fish. Soc. 94(4):
358-362, October 1965.

Eschmeyer, P. H. The Life Histroy of the Walleye, Stizostedion
vitreum vitreum (Mitchill), in Michigan. Ann Arbor, Mich. Dept.
Conserv., Inst. Fish. Res. Bull. 3. 1950. 99 p.

Grinstead, B. G. Reproduction and Some Aspects of the Early Life
History of Walleye, Stizostedion vitreum (Mitchill), in Canton

Reservoir, Oklahoma. In: Reservoir Fisheries and Limmology,
Hall, G. E. (ed.). Washington, Amer. Fish. Soc. Spec. Pub. No. 8.
1971. p. 41-51.

Johnson, F. H. Walleye Egg Survival During Incubation on Several
Types of Bottom in Lake Winnibigoshish, Minnesota, and Connecting
Waters. Trans. Amer. Fish. Soc. 90(3):312-322, July 1961.
Niemuth, W., W. Churchill, and T. Wirth. The Walleye--Its Life
History, Ecology, and Management. Madison, Wisc. Conserv. Dept.
Pub. 227. 1959. 14 p.

61


Eggs fertilized at 9 C had a percentage hatch which varied from 80.4%
at an incubation temperature of 18 C to 46.2% at an incubation temper-
ature of 6 C. With fertilization at 12 C the percentage hatch ranged
from 32.0% at an incubation temperature of 12 C to 0.0% at 21 C. The
percentage hatch of eggs fertilized at 15 C ranged from 77.0% at an
incubation temperature of 12 C to 1.0% at 21 C. With fertilization at
18 C the percentage hatch ranged from 58.6% at an incubation temperature
of 12 C to 0.0% at 6 C. By separation of the effects of fertilization
temperature and incubation temperature on egg survival it was deter-
mined that egg survival was greatest at incubation temperatures from
12-15 C regardless of the fertilization temperature. Egg survival was
lowest at an incubation temperature of 6 C. Egg survival rates (Table
12) at incubation temperatures of 12-15 C were 75.7-77.8%, 32.0-27.2%,
77.0-73.5% and 58.6-54.0% at fertilization temperatures of 9, 12, 15,
and 18 C, respectively. Survival of eggs fertilized at these four
temperatures but incubated at 6 C was 46.2%, 1.7%, 2.0%, and 0.0%, re-
spectively.

Effect of Constant Temperature on Eggs and Fry

Sauger eggs and fry were held in six constant temperatures through
fertilization, incubation, and after hatching to the juvenile stage.
Survival of eggs, sac fry, and juveniles, time to hatch, and size of
the fry at hatch were determined (Table 13). Highest egg survival was
at 9 and 15 C with 72.2% and 73.5% hatching. At 12 C and 18 C, 32.0%
and 44.5% hatched.

'
Incidence of abnormalities in hatched fry increased as the temperature

increased. The percentage of abnormal fry was low at 6, 9, and 12¢
where 2.0%, 2.0%, and 3.5% of the total hatch was abnormal. At a tem-
perature of 15 C the percentage of abnormal fry was high (18.0%) but
then dropped to 3.3% at 18 C. At 21 the incidence of abnormalities
was highest (23.0%). The percentage abnormal fry were included in the
percentage of total hatch.

47


incubation temperature of 12 C to 0.0% at incubation temperatures of
18 and 21 C. At a fertilization temperature of 18 C the percentage
hatch ranged from 41.0% at an incubation temperature of 15 C to 1.0%
at an incubation temperature of 21 C. The percentage hatch of eggs
fertilized at 15 C ranged from 15.0% at the incubation temperatures of
12 and 15 C to 0.0% at the incubation temperatures of 18 and 21 C. At
a fertilization temperature of 12 C the percentage hatch ranged from
61.5% at an incubation temperature of 12 C to 10.0% at an incubation
temperature of 21 C. Eggs fertilized at 9 C resulted in a percentage
hatch that ranged from 73.0% at an incubation temperature of 15 C to
23.0% at an incubation temperature of 21 C. With fertilization at 6
C the percentage hatch ranged from 84.0% at an incubation temperature
of 6 C to 0.0% at an incubation temperature of 21 C.

The effect of incubation temperatures on the hatchability was modified
substantially by temperature at fertilization. Independent of the
effect of fertilization temperature the greatest percentage. hatch was
at incubation temperatures of 9-15 C. The lowest percentage hatch was
at incubation temperatures of 6 and 21 C. The only exception was at
a fertilization temperature of 6 C and an incubation temperature of

6 C, where 84.0% hatch was obtained. The 21 C incubation temperature
appears to be lethal for eggs fertilized at all temperatures. At the
incubation temperatures of 6 to 18 C there was a mean difference be-
tween the highest and lowest percentage hatch of 19.5% (range 10.0-
30.0) for all fertilization temperatures. The incubation temperature
of 21 C was not included in this analysis for the reasons stated above.
The TL50, when maximum hatch is greater than 50%, of the incubation
temperature for each fertilization temperature was 19.0 C for the fer~
tilization temperatures of 6 and 12 C and 20.1 C for the fertilization
temperature of 9 C.

To determine whether any interaction occurred between the fertilizatior

21


SECTION V

WALLEYE EGG AND FRY SURVIVAL

EXPERIMENTAL DESIGN

Walleye adults were acclimated to six different temperatures, 6, 9, 12,
15, 18, and 21 C. After the adults became ripe, the fish were stripped
and the eggs were fertilized at the same six temperatures. To separate
the effects of fertilization (parental) temperature and incubation
temperature on the hatchability of eggs, the eggs fertilized at each
temperature were incubated at six different temperatures, 6, 9, 12, 15,
18, and 21 C. The fry hatched at these temperatures were carried
through at the same six temperatures to determine fry survival to yolk
sac absorbtion and to the juvenile stage. This design is schematically

shown in Figure 4.

HATCHABILITY OF WALLEYE EGGS
Effect of Fertilization Temperature on Hatch

The tests described above on walleye eggs determined the optimum in-
cubation and fertilization temperature range for hatch and permitted
separation of effects of incubation temperature, fertilization tem-

perature, or interaction between the two on egg mortality (Table 3,

Figure 5).

The lowest fertilization temperature, 6 C, resulted in the highest per-
centage hatch for each of the incubation temperatures except for the
highest, 21 C, where 0.0% of eggs survived. A maximum hatch of 84.0%
was obtained at a fertilization temperature of 6 C and an incubation
temperature of 6 C. As the fertilization temperature increased the
percentage hatch progressively decreased with the highest fertilization
temperature resulting in the lowest percentage hatch. At a fertiliza-
tion temperature of 21 C the percentage hatch ranged from 10.0% at an

17


SECTION VI
GROWTH OF JUVENILE WALLEYES

EXPERIMENTAL DESIGN

Two experiments were conducted to determine the optimum temperature
for growth of walleye juveniles in 1971 and 1972. The growth tests
were made in constant-flow chambers of 25-liter capacity. Temperatures
from 16-28 C were used and all tests consisted of two replicates with
10 fish in each. The replicates were combined in the final analysis
since there was no significant difference at the .05 level found be-
tween them. The fish were distributed randomly to the respective
chambers and acclimated therein. They were allowed to feed on an
excess of small fathead minnows (Pimephales promelas). The walleyes
were weighed and measured to 0.01 g at the beginning and at the com-
pletion of the 28-day test. To facilitate measurement they were
anesthetized with tricaine methanesulfonate (MS 222) at a concentra-
tion of 100 mg/liter. Total length was measured to the nearest milli-

meter.

GROWTH AT 16 C, 21 C, AND 25 C (1971)

In 1971 walleye juveniles were grown at three temperatures: 16, 21, and
25 C (Table 7). Mean weights of the fish at the beginning of the test
were 2.00, 1.91, and 1.81 g at 16, 21, and 25 C, respectively. The
greatest increment in length and weight was at 25 C with an increase
in length of 69.7% and in weight of 429.3%. The specific growth rate
was 5.950. Growth decreased progressively with a decrease in tempera-
ture, with the lowest gain in weight occurring at 16 C where the fish
increased 35.5% in length and 156.5% in weight. The corresponding

specific growth rate at this temperature was 3.371.

29


TEMPERATURE (°C)

Slr TLio
30r TL 99
29

T

26r
27F

26r

8 10 12 14 16 1820 22 24 26
ACCLIMATION TEMPERATURE (°C)

Figure 9. TL1O and TL90 levels of sauger juveniles
exposed to upper lethal temperatures. TL10 and TL9O
were at 10 and 90% survival plotted on arithmetic
paper.


1.

ANNOTATED BIBLIOGRAPHY

Allbaugh, Clyde A., and Jerry V. Manz Descriptors

1964. Preliminary study of the effects of WALLEYE
temperature fluctuations on developing LAKE ERIE
walleye eggs and fry. Prog. Fish-Cult. INCUBATION

26(4): 175-180.
A study of the effect of fluctuating temperatures on different
stages of embryo development of walleye eggs was done at Put~In-
Bay in western Lake Erie. The study was started at 6.7 C and was
raised 0.56 C every 48 hours. The rising temperature of the system
was called the base temperature or the normal rise in water tempera-
ture during incubation of walleye eggs. The temperature fluctuation
test was administered by slowly raising the water temperature 4.4 C
in 4 hours, and then gradually reducing to the base temperature.
The temperature fluctuation was applied at 4 stages of embryo develop-
ment: cleavage, differentiation, organogenesis, and hatching. 28%
of the eggs hatched in the control, 30% of the eggs hatched when the
temperature was fluctuated at cleavage, 28% of the eggs hatched when
the temperature was fluctuated at differentiation, and 39% of the
eggs hatched when the temperature was fluctuated at organogenesis.
Due to an accident the water temperature rose to 1.1 C during hatching
and no excessive mortalities occurred in 7 out of 8 hatching jars.
The author concluded that 399 temperature units are required for
normal development and hatching, when 1 temperature unit = 1 degree-
day above 32 F.

Anonymous Descriptors
1967. Temperatures for hatching walleye WALLEYE
eggs. Prog. Fish-Cult. 29(1): 20. WISCONSIN
INCUBATION

At a Wisconsin hatchery, jars containing 1.5 quarts of walleye eggs
were set up to test temperatures ranging from 12.8-19.4 C in incre-
ments of 1.7 C. Additional tests were set up at 21.7 C and 23.9 C

71


Table 4. TIME TO MEDIAN HATCH IN DAYS FOR WALLEYE EGGS INCUBATED AND
FERTILIZED AT 6 DIFFERENT TEMPERATURES

Nominal
incubation Nominal fertilization temperature,
temperature, Cc
Cc 6 9 12 45 18 21
6 34 34 33 33 35 33
9 26 27 25 25 26 25
12 16 17 15 14 14 16
15 10 : il 10 10 10 10
18 7 8 7 - 7 --
21 - 6 5 _ -- -_

23


39.

40.

warm up in the spring causing early spawning activity then followed
by a cold spell, the walleyes leave the spawning grounds before
spawning is completed. It was found that the younger, smaller
female walleyes were capable of spawning later when water tempera-
tures warmed up again. Since the complete ripening of eggs is
earlier for the larger walleyes, the eggs in the smaller females
do not suffer the same delay when unfavorable weather conditions
postpone spawning.

Smith, Lloyd L., Jr., and Richard L. Pycha Descriptors
1960. First-year growth of the walleye, WALLEYE

Stizostedion vitreum vitreum (Mitchill), MINNESOTA

and associated factors in the Red Lakes, GROWTH

Minnesota. Limnol. Oceanogr. 5(3):

281-290.
An attempt was made to correlate first-year growth of walleyes in
Red Lakes, Minnesota with air degree-days above 45 F and air
degree-days above 50 F for the following months: 1) May, June,
July; 2) May, June, July, August; 3) July, August; 4) August; 5)
August, September; 6) September; and 7) the last two weeks in
July, August, and September for a 17-year period, 1940-1956. They
all showed a positive correlation with growth of young walleyes,

but none were significant below the 15% level.

Spinner, John Descriptors
1968. Environmental effect on the spawning WALLEYE

run of northern pike and walleye in the TOWA
upper Mississippi River. Proc. of North SPAWN
Central Warm-Water Fish Culture Work-
shop, Iowa Coop. Fish. Unit, 1968: 9-12.
Walleye spawn in the upper Mississippi River when temperatures
are 7.8-8.9 C. For management purposes it was suggested that
peak of walleye egg taking is when the temperature reaches 8.9-
11.1. Tests were made on walleye eggs taken from the Mississippi

89


SECTION III
INTRODUCTION

Increased steam power requirements will add to problems of thermal
pollution during the immediate future. It is therefore important to
define temperature requirements for all life history stages of fish.
The effect of temperature is most critical during the early life his-
tory stages but is probably most noticeable for its effect on sustained
growth and survival.

The determination of temperature effects on the early life history
stages of the walleye, Stizostedion vitreum vitreum (Mitchill), and
sauger, Stizostedion canadense canadense (Smith), is necessary to
establish thermal criteria for these species. To determine tempera-
ture influence on early life history stages of walleyes and saugers

both optimum and critical temperatures must be defined. Definitive
information is scarce on detrimental effects of high temperatures on
the Stizostedion species as well as optimum temperatures for different
life stages. Many authors have reported that walleye spawning generally
takes place in a temperature range of 6-12 C (Bradshaw and Muir’, cobb”,
Eddy and surber?, Ellis and Giles’, Eschmeyer, Grinstead’, Johnson’,
Niemuth et ai.®, Payne’, Priege1°, Rawson! , Schumann, and Spinner’) .
Others have reported that sauger spawn generally at the same tempera-

ture range as the walleye (Carufe1!*, Nelson?, and Priege1!®) , Priegel?

7
reported that walleye eggs will hatch in 21 days at temperatures of 10-
12 C while saugers will hatch in 13-15 days at that temperature.

Various authors have reported thermal effects on egg survival. steuckel®
concluded that the apparent optimum temperature range for hatching
walleye eggs is 16.7-19.4 C. Furthermore it was pointed out by Allbaugh
and Manz)? that temperature fluctuations during incubation of ‘walleye

eggs had no great effect on the percentage hatch. Johnson’ showed that


because of the high percentage of hatching success at the higher
temperatures. The results of the tests were as follows:

Temperature Days to Days to Percentage
(c) eye-up hatch hatch
12.8 7 10 50
14.4 6 10 50
16.1 5 8 51
17.8 4 8.5 65
19.4 3.5 60
21.7 3 10
23.9 3 10

The author concluded that the apparent optimum temperature for
hatching walleye eggs is 17.8-19.4 C.

Arnold, Dean E. Descriptors
1969. The ecological decline of Lake Erie. BLUE PIKE
N. Y. Fish Game J. 16(1): 27-45. LAKE ERIE
DISTRIBUTION

There are five main hypotheses to explain the decline and the
extinction of the blue pike (Stizostedion vitreum glaucum) in
Lake Erie that have been proposed by various schools of thought.
They are: 1) high temperature, 2) 0, depletion in the central
basin, 3) overfishing, 4) pollution, and 5) new predators or com-
petitors. All of these are probably interrelated and mutually
responsible. The blue pike have been restricted to the colder
waters of the lake, thus being placed at a disadvantage as the

waters become warmer.

Bradshaw, J., and B.S. Muir Descriptors
1960. The 1960 spawning run of yellow pickerel WALLEYE
at Bobcaygeon in relation to water ONTARIO
temperature. Ont. Dept. Lands & SPAWN

Forests, Southeastern Region, Spec.
Fish. Wildl. Bull. 3: 4-6.

72


16.

17.

18.

Ferguson, R. G. Descriptors

1958. The preferred temperature of fish WALLEYE
and their midsummer distribution in SAUGER
temperate lakes and streams. J. Fish. DISTRIBUTION

Res. Bd. Canada 15(4): 607-624.
The preferred temperature for walleyes is 22.7-23.2 C, and the

preferred temperature for saugers is 18.6-19.2 C.

Forney, John L. Descriptors
1966. Factors affecting first-year growth WALLEYE
of walleyes in Oneida Lake, New York. NEW YORK
N.Y. Fish & Game J. 13(2): 146-167. GROWTH

Annual May-June air temperatures suggest that lake temperatures
determine the rate of walleye growth in early summer and to some

extent may influence the time of hatching of walleye fry. ‘

Grinstead, Bobby G. Descriptors

1971. Reproduction and some aspects of the WALLEYE
early life history of walleye, Stizo- OKLAHOMA
stedion vitreum (Mitchill), in Canton SPAWN

Reservoir, Oklahoma. In Reservoir

Fisheries and Limnology, Amer. Fish.

Soc., Spec. Pub. No. 8, p. 41-51.
Walleyes in Canton Reservoir, Oklahoma spawn in March. Water
temperatures during peak spawning activities ranged from 5.0-
12.8 C in 1966, 7.2-14.4 C in 1967, and 3.9-8.9 C in 1968. It
was suggested that these data support the theory that water tem-
perature is the primary controlling influence in determining the
time walleyes spawn. In Canton Reservoir they spawn considerably
earlier in the year, but within temperature ranges similar to

walleyes in other regions.

78


ACKNOWLEDGMENTS

The authors wish to thank Donavon M. Oseid for assistance in logis-
tical problems; the Minnesota Department of Natural Resources for
assistance in acquiring walleyes and saugers; the Wisconsin Depart-—
ment of Natural Resources for their assistance in obtaining adult
saugers; and Robert G. Ruesink and Michael Bronowski for their

assistance in laboratory operations.


11.

12.

13.

Eddy, Samuel Descriptors
1938. A classification of Minnesota lakes WALLEYE
for fish propagation. Prog. Fish- MINNESOTA
Cult. 41: 9-13. DISTRIBUTION

Minnesota lakes were classified on the physical, chemical, and
biological features. Pike Lake No. 1 has summer temperatures of
surface water range between 15.6-23.9 C and bottom waters between
6.7-12.8 C. The difference between the summer surface and bottom
temperatures is usually 5.6-11.2 C. Pike Lake No. 2 has summer
surface temperature range between 20.0-23.9 C or higher and bottom
temperatures range between. 18.3-21.1C. The difference between

surface and bottom temperatures is 0.56-2.8 C.

Eddy, Samuel, and Thaddeus Surber Descriptors
1943. Northern fishes with special reference WALLEYE
to the upper Mississippi valley. MINNESOTA
Univ. Minnesota Press, 276 p. SPAWN

In Minnesota the spawning run of walleyes starts when water tem-

peratures range from 3.3-6.7 C.

Eley, Rex L., Neil E. Carter, and Troy C. Dorris Descriptors
1967. Physiochemical limnology and related WALLEYE

fish distribution of Keystone Reservoir. OKLAHOMA

In Reservoir Fishery Resources Symposium, DISTRIBUTION

p. 333-357. Reservoir Comm. Southern

Div., Amer. Fish. Soc.
Temperature and other limological parameters were measured at
each meter of depth at different stations in Keystone Reservoir,
Oklahoma. Depth distribution of fish was determined by suspending
a vertical latin-square gill net from the water surface to the
bottom for two consecutive 24-hour periods per month at each
station. Walleyes were captured within 4 meters of the surface
during the summer when temperatures ranged from 26-27 C.

76


region:
Range of water temperature (C)
Spoehr's Marsh Fox River Marshes Lake Winnebago
During During During During During During

spawning egg de- spawning egg de- spawning egg de-

Year velopment velopment velopment
1960 5.6-12.2 7.2-18.9 4.4-12.2 5.6-15.0 - -
1961 2.2-10.0 2.2-15.6 3.3-10.0 6.7-16.7 - -
1962 2.2-12.2 2.2-15.6 5.6-10.0 5.0-15.6 - -
1963 5.6-12.2 2.2-12.8 4.4-11.1 6.7-14.4 - -
1964 - - 5.6-10.0 4.4-15.6 5.6-11.1 5.0-12.8

1965 6.1-8.9 5.0-14.4 5.0-14.4 5.6-15.6 5.6-7.8 5.6-10.0
1966 4.4-8.3 4,4-11.1 4.4-13.3 6.7-15.0 6.7-10.6 6.1-10.6
1967 4.4-11.1 6.7-13.3 6.1-15.6 6.1-17.8 3.9-7.8 4.4-10.6
In the Lake Winnebago region, cold weather prolonged the spawning
activity over an extended period of time. It was never inhibited.
Most rapid embryo development and short incubation periods were
associated with daytime temperatures above 10.0 C and high mini-
mum water temperatures that did not fall below 7.2 C for any
extended length of time. No correlation between water temperature

and embryo survival was found.

Rawson, D.S. Descriptors
1957. The life history and ecology of the WALLEYE
yellow walleye, Stizostedion vitreum, SASKATCHEWAN
in Lac la Ronge, Saskatchewan. Trans. SPAWN
Amer. Fish. Soc. 86(1956): 15-37. DISTRIBUTION

It was suggested that water temperature appeared to be the con-
trolling influence for the walleye spawning run. No spawning
activity was observed in water temperatures below 3.3 C. The
main spawning run in Lac la Ronge took place at a temperature of
4.4-5.6 C. Active spawning was observed between 7.2-10.0 C. No
evidence was found that walleyes selected, or moved into, water of

any particular temperature range during the summer. However, it

87


Table 16.

MEDIAN SURVIVAL TIME (MINUTES) OF JUVENILE SAUGERS

ACCLIMATED TO 10 - 26 C AND EXPOSED TO UPPER LETHAL TEMPERATURES

Acclimation Test temperature,
temperature, i4
id 27.0 28.0 29.0 30.0 31.0 32.0

10.1 114 - - - - -
12.0 260 68 - - - -
13.9 - - 32 16 - -
16.0 - - 29 18 - -
18.3 - - 31 19 - -
19.9 - - - 1328 122 -
22.0 - - - 1512 545 -
23.9 - - - - 1242 348
25.8 - - - - 690 246

55


Ts

Table 14. GROWTH OF SAUGER JUVENILES FOR 36 DAYS AT DIFFERENT TEMPERATURES

Mean length Mean weight Specific
Temper- at start of Increase Increase at start of Increase Increase growth
ature, test, in length, in length, test, in weight, in weight, rate, Survival,
id mm mm A _£ Z vA Z/day 1a
16.1 96.0 13.5 14.0 5.85 3.06 52.2 1.164 100
18.1 93.5 19.0 20.3 5.33 4.23 79.4 1.617 100
20.0 95.5 16.5 17.3 5.80 3.65 62.9 1.358 90
22.0 96.0 22.0 22.9 5.62 5.44 96.8 1.883 100

26.0 99.0 13.5 13.6 6.42 3.46 53.9 1.200 60



Table 1 (continued), TEMPERATURE, pH, DISSOLVED OXYGEN (02),

TOTAL ALKALINITY OF TEMPERATURE EXPERIMENTS

Observed temperature

Nominal Standard Mean Mean
temperature, Mean, deviation, oy TA

Test c Cc Cc pH mg/l mg/1_
Walleye 18 18.1 +0.13 8.1 7.6 232
juvenile 20 20.2 #0.15 8.1 7.0 232
growth IL 22 22.1 +0.08 8.2 7.0 225
24 23.9 +0.08 8.2 6.8 234
26 26.0 +0.12 8.3 6.1 237
28 28.0 40.14 8.2 6.1 215
Sauger 16 16.1 +0.09 8.2 7.9 230
juvenile 18 18.1 40.08 8.2 6.8 234
growth 20 20.0 40.12 8.3 7.0 237
22 22.0 40.11 8.3 6.1 237
26 26.0 +0.10 8.3 5.8 232

13


creased from 27.0 to 29.5, then at the acclimation temperatures of
16.0 to 22.0 C the upper lethal temperature remained stable at 30.5-
30.6 C. The TL50 increased slightly to 31.5 and 31.6 C for the
acclimation temperature of 24 and 26 C, respectively. In most cases
there was a temperature difference of 1 C between 90-100% survival
and 0-10% survival. This effect is shown in Figure 7 where both
TL9O and TLIO are plotted.

42


Table 12. PERCENTAGE HATCH OF SAUGER EGGS FERTILIZED AT
FOUR TEMPERATURES AND INCUBATED AT SIX TEMPERATURES

Fertilization Incubation temperature,
temperature, Cc
c 6.0 8.9 12.0 15.0 18.1 20.9
9.2 46.2 72.2 75.7 77.8 80.4 65.7
11.9 1.7 14.8 32.0 27.2 2.2 0.0
15.0 2.0 34.0 77.0 73.5 12.0 1.0
18.2 0.0 25.5 58.6 54.0 44.5 42.0

46


10.

Doan, Kenneth H. Descriptors

1942. Some metereological and limnological WALLEYE
conditions as factors in the abundance BLUE PIKE
of certain fishes in Lake Erie. SAUGER
Ecol. Monogr. 12(3): 294-314. LAKE ERIE

SIZE OF CATCH
Because water temperature has considerable influence over the
success of fishing, an attempt was made to correlate the size of
the catch of walleyes, blue pike, and saugers in Lake Erie with
mean spring air temperatures.
Walleyes: Spring temperatures have shown no relation to sizes of
catch. Mean April-May air temperatures at Cleveland, Sandusky,
and Toledo had non-significant "r" values with Ohio catches in
the same year, and with catches 3 or 4 years later.
Blue Pike: Temperature variations affect the stock of blue pike
by affecting the vulnerability of adults to capture and by in-
fluencing spawning and fry survival. Over half of the total blue
pike catch is taken in May and June, these months also include
spawning and early fry stages. However there was no correlation
between the mean May-June air temperatures at Cleveland and Erie
and the size of the Ohio catches of blue pike the same year. But
there was a definite relation between May-June air temperatures
and the catch of blue pike 2 years later.
Sauger: There was no significant correlation with catches of
sauger and mean spring air temperatures.
It was thought that in Lake Erie the factor to which these fish
react most strongly would be temperature since they seek colder
waters in the summer by going deeper. To support this view,
movements of tagged blue pike and walleyes in Lake Erie were ob-
served. The blue pike inhabited the colder waters, and the wall-
eyes were more tolerant of warmer water but still moved eastward
out of the excessively higher temperature waters during the
summer in the western section of the lake.

75


HEAD TANK

INCUBATION
CHAMBERS

—D

FRY AND

JUVENILE
CHAMBERS

Figure 1. Diagram of the experimental apparatus showing the head tank,
incubation chambers, and fry chambers.

8


SECTION X
GROWTH OF JUVENILE SAUGERS

Optimum temperature for growth of sauger juveniles was determined in
a test running 36 days and conducted in the same manner as that des-
cribed above for walleye growth experiments. Saugers were tested at

2 C intervals ranging from 16 to 26 C (Table 14). A malfunction in the
apparatus caused total loss of fish at 24 C. The mean weight of the
fish at the beginning of the test was 5.85 g at 16 C, 5.33 g at 18 C,
5.80 g at 20 C, 5.62 g at 22 C, and 6.42 g at 26 C. Maximum growth
was at 22 C where the fish increased 22.9% in length and 96.8% in
weight, corresponding to a specific growth rate of 1.883. Minimum
growth was at 16 C, the lowest temperature, where the juveniles

gained 14.0% in length and 52.2% in weight and corresponding to a.
specific growth rate of 1.164. At 26 C the percentage gains in
length and weight and the specific growth rate were 13.6%, 53.9%,

and 1.200, respectively. At 18 C the fish gained 20.3% in length,
79.4% in weight, and had a specific growth rate of 1.617. At 20 C
the fish increased their length 16.5%, weight 62.9%, and had a specific
growth rate of 1.358.

Juvenile mortality occurred at the high temperature (26 C) where the

percentage survival was 60%.

50


FIGURES

Diagram of the Experimental Apparatus

Diagram of the Continuous Flow-Through Incubation
Chamber

Diagram of the Incubation Cylinder

Schematic Diagram of the Experimental Design
for the Egg and Fry Experiments

The Combined Effect of Fertilization Temperature
and Incubation Temperature on the Hatchability
of Walleye Eggs

Growth of Walleye Juveniles Exposed to Temperatures
Ranging from 18 C to 28 C

TL10 and TL90 Levels of Walleye Juveniles Exposed
to Upper Lethal Temperatures

The Combined Effect of Fertilization Temperature
and Incubation Temperature on the Hatchability
of Sauger Eggs

TL1O and TL90 Levels of Sauger Juveniles Exposed
to Upper Lethal Temperatures

av

10

18

20

32

43

45

53


Appendix A, Table 2
DUMMY VARIABLES REPRESENTING FERTILIZATION TEMPERATURE
IN THE REGRESSION EQUATIONS FOR DETERMINING
THE SIZE OF WALLEYE FRY AT HATCH
Variables Used in Equations for Incubation Temperatures
of 6, 9, 12, and 15 C

Nominal
fertilization
temperature, Dummy variables
c xy x, X x 4 Xs
6 1 0 0 0 0
9 0 1 0 0 0
12 0 0 1 0 0
15 0 0 0 1 0
18 0 0) 0) 0 1
21 -1 1 -1 -1 -1

67


temperature and the incubation temperature, a statistical analysis was
done using a 3-dimensional contingency table (Feinbere””) . Setting
up the data in a 6 x 6 x 2 contingency table and by comparing the
Freeman-Tukey Deviations, it was determined that the only place where
statistically real interaction occurred was at the 6 C incubation and
6 C fertilization temperatures. At this point there was an unexpected
high percentage egg survival. The observed survival was 84.0% while
the expected egg survival was 64.29%. Appendix A, Table 1 lists all
expected values of egg survival for all incubation and fertilization

temperatures.

Effect of Fertilization Temperature on Fry Size

Walleye fry hatched from eggs fertilized at six different temperatures,

6-21 C, were measured from each of the six incubation temperatures.

Time to hatch did not vary between fertilization temperatures within
each incubation temperature (Table 4), but the size of the fry showed
a significant difference at the .05 level between the fertilization
temperatures for each incubation temperature, except at the incubation
temperature of 18 C. It was determined from regression analysis that
the size of the fry at each fertilization temperature played a signi-
ficant part in the regression equations calculated for each incubation
temperature. The regression equations were determined with the use of
dummy variables representing each fertilization temperature. This
procedure was done to avoid testing only for a straight line. The
dummy variables are presented in Appendix A, Tables 2 and 3. The
regression equations determined for each incubation temperature are as
follows:

6C Y= 1.6054 + -0143K, + +0124x, - -0035K, - +0137K,
- -0088K, + .0036X, qd)

22


SECTION XIV

APPENDIX A

STATISTICAL TABLES

65


15 C is more detrimental to egg survival than 18 C. It is believed
that eggs fertilized at 15 C were of poor quality and less viable for
an undetermined reason, but the egg mortality from this cause was con-
sistent and independent of the incubation temperature or occurred
before the incubation temperature had any effect. The shape of the
15 C fertilization curve shown in Figure 5 is the same as that for
other temperatures but probably should lie between the 12 and 18 C
curves. This descrepancy was also noted with saugers fertilized at
12 C (Table 12, Figure 8). It is believed that these eggs were also

less viable for some reason other than temperature.

Incidence of abnormalities was affected by temperature. Both walleyes
and saugers showed a substantial increase in abvormalities as the

temperature increased.

The size of the walleye fry at hatch was affected by fertilization
temperature as well as incubation temperature. The results indicate
that lower fertilization temperatures resulted in larger fry. The
sauger fry did not show any significant variation in size attributable
to the fertilization temperatures.

Optimum temperature for walleye growth was influenced by the size of
the juvenile. Smaller fish (mean weight 1.91 g) had a higher optimum
temperature (25 C) than the larger fish (mean weight 4.59 g) (22 C).
This shift in the optimum temperature could have been caused by dif-
ferences in dissolved oxygen. Juvenile saugers also had an optimum
temperature for growth of 22 C. These fish were uniform in size so no
variation due to size difference was noted. The preferred temperature
of fish according to Brett”° is also the optimum temperature for ac—
tivity and growth, thus the preferred temperature for walleye juveniles
is estimated to be 22-25 C. Fry?’, Doudoroft”®, Proffitt??, and

Merriman?? have noted the tendency for young fish to remain in warm

58


to the test temperatures which ranged from 6 to 21C. The water tem-
perature was controlled in each tank with a polyethylene heat ex-
changer. After acclimation temperature was reached the fish were
held from 1 to 2 days before being stripped. The fish were stripped
when eggs were released by the females when minimum pressure was

applied to the lower abdomen.

Juveniles were captured in the field when the water temperature
ranged from 18 to 24 C. At the laboratory, they were given a pro-
phylactic treatment of 20 mg/liter neomycin sulfate for 3 days before
the acclimation process was started. The holding tanks were then
flushed and the temperature was raised with a polyethylene heat ex-
changer. The fish were acclimated at a rate of 2 C/day and were held
at the desired test temperature for at least 2 weeks before testing
was initiated. During acclimation fish were fed with fathead minnows.
The fish were held in a flow-through system thus requirements for
cleaning tanks were minimal. Tanks were siphoned clean every other
day. At the time of testing fish were transferred in plastic pails
to the test chambers without going through a temperature change.

EGG STRIPPING

Adult fish were stripped and eggs were fertilized at the same water
temperature to which the adults were acclimated. Eggs from two females
were stripped into a Nalgene beaker, then seconds later milt was
stripped from two males and mixed thoroughly with the eggs. At the
same time the milt was added, water at the required fertilization tem-
perature was gradually introduced and mixed. Finally bentonite clay
was added to the fertilized eggs to prevent clumping. The eggs were
then rinsed clean and the beaker was then placed in a water bath to
acclimate the eggs to their respective incubation temperatures and
allow them to water harden. Within 1 hour after fertilization the

eggs were examined under a microscope and 100 to 300 pooled eggs were

15


10.0

9.0F

7.0)

WEIGHT GAIN (G)

6.0F

Figure 6.

is 20 22 24 26 28
TEMPERATURE (°C)

Growth of walleye juveniles exposed to temperatures ranging
from 18-28 C. Line A represents the actual data points.
Line B represents the predicted points cglculated from the
equation, Y = -50.917 + 5.3740K - .1211x".

32


SECTION XI

UPPER LETHAL TEMPERATURES FOR SAUGER JUVENILES

EXPERIMENTAL DESIGN

Upper lethal temperature (TL50) tests were conducted on juvenile
saugers acclimated to temperatures from 10 to 26 C at 2 degree inter-
vals. The fish which had a mean total length of 119 mm were acclimated
in 25-liter flow-through chambers in groups of 24 for a period of 2
weeks prior to the test. After acclimation the fish were randomly
divided into three groups of eight fish. Each group was then subjected
to a sudden temperature change by transferring the fish directly from
the acclimation chamber to a higher test temperature. Fish were not
fed for 96 hours prior to testing.

LETHAL TEMPERATURE TESTS

After acclimation upper lethal temperature was tested and time of death
for each individual fish was recorded. The upper lethal temperature
is defined as in the walleye experiments above. Upper lethal tempera-
tures are shown in Table 15 and Figure 9 and median survival times

are on Table 16.

Fish acclimated to 10 C and 12 C had an upper lethal temperature of
26.6 C and 26.7 C, respectively. Of the fish acclimated to 10 C and 12
C, 12.5% and 25.0%, respectively, survived at 27 C, while 100% survived
at 26 C. The median survival times of the fish exposed to 27 C were
114 minutes for those acclimated at 10 C and 260 minutes for those
acclimated at 12 C. The median survival time of fish acclimated to

12 C and exposed to 28 C was 68 minutes. Fish acclimated to 14, 16,
and 18 C had an upper lethal temperature of 28.4, 28.6, and 28.7 C,
respectively. The percentage survival of the fish acclimated to 14,

52


8T

AouLT
o

00
ere

E99 £00 £00 E00 aa £00
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PRY FRY FAY FRY FRY FRY
1G BPC Jah IBC IBC ZIC

3

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ec FC 1a%c 18°C 1ere 21°C

Figure 4.

ADULT ACCLIMATION

ApuLt
ae

FERTILIZATION

Gg

M

EGG ACCLIMATION

AN

E90 £00 E00 £00 £00 £00
°C 9c 1a8e WSC 10NC ZIP

INCUBATION

FRY FRY FRY FRY FAY FRY
6c otc 1ac wre ler 2ic

FRY SURVIVAL

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6°C 9G 12° 18°C Iere 2i°C

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eee

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ec

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AY PRY FRY
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abuLT
were

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eC OFC 12% IBC 18°C 21°C

FRY FRY FRY FRY FRY FRY
°C BRC IRPC 18°C 18°C 2IPC

FRY FRY FRY FAY FRY FRY
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ADULT ACCLIMATION

ADULT
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FERTILIZATION

EGG ACCLIMATION

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33

3

FRY SURVIVAL

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@°C 98 IR8c IBC 18°C aie

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are

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FRY FRY FAY FRY PAY FRY
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@°C BPC IRC 18C 18°C ZIP

Schematic diagram of the experimental design for the egg and fry experiments.


30.

31.

32.

Payne N. R. Descriptors
1964. The life history of the walleye, WALLEYE
Stizostedion vitreum vitreum (Mitchill), ONTARIO
in the Bay of Quinte. M.A. Thesis, YEAR-CLASS
Univ. Toronto, Toronto, Ont. 40 p. STRENGTH

In lake Ontario walleye spawning commences when the water tempera—
ture reaches above 3.3 C and is completed by the time the water
temperature is 10.0 C. There is a strong indication that there is
a relationship between April air temperatures and the size of
year-classes of walleyes in the Bay of Quinte. All strong year-
classes occurred in the years when the April mean air temperatures
were above normal. Weak year-classes were produced in the two
years when the April mean temperatures were subnormal. But also
there were weak year-classes produced in 1949, 1953, and 1958 when
April mean temperatures were above normal. It was concluded from
these facts that 1) above normal temperatures at spawning time
are required for the production of astrongyear-class, 2) sub-
normal April mean temperatures result in the development of weak
year-classes, and 3) above normal temperatures alone are not suf-
ficient to cause better than average spawning success. It was
also suggested that it is feasible that May and June temperatures
also are of some importance in enhancing or nullifying the effect

of April temperatures.

Priegel, Gordon R. Descriptors
1963. Walleye nursery. Wisc. Conserv. Bull. WALLEYE
28(2): 6-7. WISCONSIN
; SPAWN

Walleye spawning in Wisconsin occurs in mid-April when the water
temperatures approach 5.6 C.

Priegel, Gordon R. Descriptors
1966. Lake Puckaway walleye. Wisc. Conserv. WALLEYE
Dept., Res. Rep. 19, 22 p. WISCONSIN
SPAWN

85


Table 10. EFFECTS OF SUDDEN TEMPERATURE CHANGE ON WALLEYE JUVENILES
EXPOSED TO A TEMPERATURE ABOVE THEIR ACCLIMATION TEMPERATURE

Acclimation Test Temperature
Number temperature, temperature, change, Survival,
of fish Cc c c ’
20 21.0 24.9 + 3.9 100
20 16.0 21.0 + 5.0 100
20 21.0 27.8 + 6.8 100
20 16.0 24.9 + 8.9 100
20 16.0 27.7 +11.8 100

39


20.

21.

22.

23.

Herman, Elmer F. Descriptors

1947. Notes on tagging walleyes on the WALLEYE
Wolf River. Wisc. Conserv. Bull. WISCONSIN
12(4): 7-9. SPAWN

The 1946 spawning run in the Wolf River, Wisconsin, started after
the ice left the river when the temperature ranged from 3.3-6.7
C. The actual spawning occurred when the temperature reached
14.4 C.

Hile, R., and C. Juday Descriptors

1941. Bathymetric distribution of fish in WALLEYE
lakes of the northeastern highlands, WISCONSIN
Wisconsin. Trans. Wisc. Acad. Sci., DISTRIBUTION

Arts, & Lett. 33: 147-187.
The average thermal distribution of walleyes during August in

Trout Lake, Wisconsin was reported to be 20.6 C.

Hurley, Donald A. Descriptors
1972. Observations on incubating walleye WALLEYE
eggs. Prog. Fish-Cult. 34(1): 49-54. INCUBATION

In the years 1969 and 1970, walleye eggs were at the eyed stage
at 274 and 234 thermal units (TU), median hatch occurred at 440
TU, completion of hatching required 467 TU's, and yolk absorption
was completed at 690 TU's. 1 TU = 1 degree-day above 32 F.

Johnson, Fritz H. Descriptors
1961. Walleye egg survival during incubation WALLEYE
on several types of bottom in Lake MINNESOTA
Winnibigoshish, Minnesota, and INCUBATION

connecting waters. Trans. Amer.

Fish. Soc. 90(3): 312-322.
Survival of naturally spawned walleye eggs was determined for five
types of bottom areas of Lake Winnibigoshish and connecting waters

80


SECTION XII
DISCUSSION

The results of this investigation show that temperature has an impor-
tant impact on walleye and sauger eggs, fry, and juveniles. The
optimum temperatures and lethal temperatures vary significantly for
different life history stages with the optima for fertilization, in-
cubation, and fry survival gradually increasing in the successive
stages. The optimum temperature ranges for fertilization, incubation,
and fry survival of walleyes are 6-9 C, 9-15 C, and 15-21 C, respec-
tively. The optimum temperatures for the same stages in sauger are
9-15 C, 12-15 C, and 15-21 C, respectively. These ranges correspond
closely to the temperatures found in nature when the various stages
are present. Under normal conditions adult sauger and walleye spawn
at temperatures of 6-12 C with the temperature gradually rising to

15 C by the time eggs hatch. Fry development takes place at 15-21 C.
On the basis of studies reported here temperature regimes must be
considered as an important factor in the establishment of year classes

and maintenance of populations in natural water.

If unusually cold weather occurs after fry emergence, fry survival
may be inhibited. Conversely strong year class may be dependent on
gradual warming of water during egg deposition and incubation, and
after fry emergence. Johnson’ stated that egg mortality, associated
with unuaully cold weather during the incubation period, may be an
important factor in the limiting of the size of year classes. Feeding
of fry may also be reduced when temperatures are low. Fry fed well
at the higher temperatures (18-21 C).

One discrepancy in the hatch data (Table 3, Figure 5) suggests that

57


over a 4-year period.

The results were:

Year Bottom Incubation Water Daily mean Estimated
type period (days) temperature water percentage
during in- temperature egg
bation (C) _ (Cc) survival
1956 Areal 20-24 5.0-16.1 8.3 0.6
"2 20-24 5.0-15.0 8.3 2.7
"3 14-16 6.1-13.3 11.1 17.5
"4 - - - 34.3
1957 Areal 12-14 7.8-8.9 11.7 4.7
"2° 12-14 8.9-14.4 11.7 9.9
"3 12-16 7.8-14.4 11.7 17.9
"4 12-16 7.8-14.4 11.7 17.4
1958 Areal 16-21 6.1-12.8 10.0 3.6
"2 16-21 6.1-12.8 9.4 35.7
(improved)
"3 _ . _ .
"4 18-21 6.1-17.8 - 5.2
"5 16-21 6.1-12.8 9.4 13.2
1959 Areal 16-18 7.2-17.2 10.6 1.2
"2 12-18 12.8-15.6 10.6 25.9
Area 1 = soft, mucky bottom
Area 2 = firm, fine sand
Area 2 (improved) = former area 2 covered with 6 inches of
gravel
Area 3 = gravel and rubble bottom with occasional boulders
Area 4 (1956) = gravel and rubble bottom
Area 4 (1957) = gradually sloping bottom with 60% gravel and
40% sand
Area 4 (1958) = gravel-rubble bar with occasional boulders
Area 5 = bar of firm clean sand

Temperature determinations were made with maximum-minimum thermo-

meters.

The author felt that observations on max-min water tem-

peratures do not lend themselves to critical analysis of the effect

81


between the fertilization temperatures. Due to the low hatch at the
incubation temperature of 21 C, the sample size was too small for any

type of statistical analysis.

Effect of Constant Temperature on Eggs and Fry

Eggs and fry were held at six constant temperatures through fertili-
zation, incubation, and after hatching. Fry were held to the juvenile
stage. Survival of eggs, sac fry, and juveniles as well as time to
hatch and size of the fry at hatch were determined (Table 6). Repli-
cates were combined in the final analysis since there was no signifi-
cant difference found at the .05 level between the replicates.

The lowest temperature, 6 C, resulted in the highest percentage hatch
(84.0%) and progressively decreased as the temperature increased, with
the highest temperature, 21 C, resulting in 0.0% hatch. As noted
above, the high egg survival at 6 C was caused by the interaction of
the fertilization temperature and the incubation temperature. If
interaction had not occurred, the hatch at 6 C (expected hatch of
64.29%) would have been about the same as the egg survival at 9 C
(66.5%) and 12 C (61.5%). Temperatures higher than 12 C had a much
lower percentage hatch with 15 C resulting in a 15.0% hatch and 18 C
in a 32.0% hatch.

Incidence of abnormalities in fry increased as the temperature in-
creased. The percentage of fry abnormalities was 1.0~-3.8% at a tem-
perature range of 6-15 C and increased up to 15-18% at 18 and 21 ¢,
respectively. Percentage of abnormal fry was included in total hatch.

Time to first hatch, to median hatch, and to the completion of hatch

roy
was 30, 34, and 49 days at 6 C; 23, 27, and 31 days at 9 C; 12, 15;
and 18 days at 12 C; 8, 10, and 11 days at 15 C; 6, 7, and 8 days at

26


lethal temperature is 31 C and 30 C for nonfeeding fish.

Based on tests when walleye juveniles were exposed to a sudden tem-
perature change, the lower lethal temperaure for walleyes accclimated
to 25 C is slightly lower than 8 C.


Table 11. PERCENTAGE SURVIVAL OF WALLEYE JUVENILES EXPOSED TO UPPER
LETHAL TEMPERATURE LEVELS FOR EACH ACCLIMATION
TEMPERATURE FOR 96 HOURS

Acclimation Test temperature,
temperature, Cc TL50,
c 26.0 27.0 28.0 29.0 30.0 31.0 32.0 33.0 ¢
8.0 100 «650 10 - - - - - 27.0
10.1 - 100 100 10 - - - - 28.6
12.1 - - 100 50 0 - - - 29.0
13.9 - - [= 90 10 0 - - 29.5
16.0 - - - 100 100 10 - - 30.6
18.2 - - - 100 =100 0) - - 30.5
20.2 - - - - 100 0 0 - 30.5
22.1 - - - - 100 0 0 - 30.5
24.0 - - - - - 90 10 - 31.5
25.8 - - - - - 100 10 0 31.6

41


SECTION I
CONCLUSIONS

The response of walleyes and sauger to temperature are not greatly
different except that the optimum range for fertilization is higher
in the sauger. The upper lethal temperature is slightly higher for
walleyes.

The optimum temperature range for egg survival in walleyes occurs
with fertilization at 6-12 C and incubation at 9-15 C. In sauger
the optimum range is 9-15 C for fertilization and 12-15 C for incu-
bation. The incubation temperature TL50 on normalized hatch data

for walleyes when maximum hatch is greater than 50% for the fertili-
zation temperatures of 6, 9, and 12 C was 19.0, 20.1, and 19.0 C,
respectively. Sauger eggs fertilized at 9, 15, and 18 C had a 50%
hatch or greater at the incubation temperatures of 6.5-21.0, 10.2-
17.5, and 11.0-17.6 C, respectively. Survival of hatched fry through
abosrption of the yolk sac is best at the same temperature range
(9-21 C) for both species. Survival to the juvenile stage requires
a relatively higher temperature (21 C) than through incubation to yolk

sac absorption.

Growth rate of juveniles is optimum for both species at 22 C. A sudden
temperature change does not appear to be a significant lethal factor
for either species until upper lethal temperature is closely approached
or very low temperature (6 C) is reached. The amount of temperature
change is not important. Upper lethal temperature for walleye is from
27.0-31.6 C and for sauger 26.6-30.4 C, depending on acclimation tem-

perature.

With acclimation to normal summer ambiént temperature (22 C) upper


ward and downward temperature change over a 72-hour period. A corrected
survival rate was determined by comparison to the controls where there

was no temperature change.

Five-day old walleye fry reared at 6 C were exposed to test tempera-
tures at 11, 16, and 21 C. Fry mortality was observed only at 21 C,
a change of +15 C, where 56% of the fry survived. No mortality was

observed at the other temperatures.

Two-day old fry reared at 11 C were tested at 6, 16, and 21 C. The
lowest survival, 58%, was at 6 C, a change of -5 C. No mortality
cccurred at 16 C, a change of +5 C. At a change of +10 C (21 C)
78% of the fry survived.

Seven-day old fry reared at 21 C were exposed to test temperatures at
6, 11, and 16 C. A 100% mortality occurred at 6 C with a change of
-15 C. No large mortality was observed at the other temperatures.
There was 91% survival at 11 C, a change of -10 C, and no mortality
at 16 C, a change of -5 C. Table 8
lists the actual and corrected percentage survival of fry for all

tests.
JUVENILE TESTS

Juvenile walleyes (80-100 mm in length) acclimated to various tempera~
tures were exposed to higher and lower temperatures for thermal treat-
ment over a 96-hour period. ‘Both lethal effects and sublethal responses
were observed. Sublethal response was recorded in terms of abnormal

behavior and food acceptance.
Walleye juveniles acclimated to 16, 21, and 25 C were exposed to tem-
peratures as much as 17 degrees below the acclimation temperature. The

only mortality that occurred, 30%, was at a temperature change of -17

35


Table 2.

CHEMICAL ANALYSIS OF LABORATORY WELL WATER

Concentration,
Item mg/liter

Total hardness as Caco, 220
Alkalinity as Caco, 230
Iron 0.02
Manganese 0.04
Chloride <i
Sulfate <5
Fluoride 0.22
Total phosphorus 0.03
Methylene blue active sub. as ABS 0.1
Calcium as Caco, 140
Sodium 6
Potassium 2
Ammonia nitrogen 0.20
Organic nitrogen 0.20
Phenols <0.005
Copper <0.01
Cadmium <0.01
Zine <0.01
Nickel <0.01
Lead <0.01

14


WO 21

“
g

RRDARS

tet tee

ale

Figure 2. Diagram of the continuous flow-through incubation chamber.

NO. 9
NEOPRENE
STOPPER


10

11

TABLES

Temperature, pH, Dissolved Oxygen (05), and
Total Alkalinity of Temperature Experiments

Chemical Analysis of Laboratory Well Water

Percentage Hatch of Walleye Eggs Fertilized at
6 Different Temperatures and Incubated at 6 Dif-

ferent Temperatures
Time to Median Hatch in Days for Walleye Eggs

Incubated and Fertilized at 6 Different Temper-
atures

Size of Walleye Fry at Hatch Calculated From the
Regression Equations

The Effect of 6 Different Temperatures on Walleye
Eggs and Fry Held at a Constant Temperature
During Fertilization, Incubation, and After
Hatching

Growth of Walleye Juveniles for 28 Days at

Different Temperatures

Effects of Temperature Change on Walleye Fry
Incubated and Reared at 6 C, 11 C, and 21 C -
72 Hours

Effects of Sudden Temperature Change on Walleye
Juveniles Exposed Below Their Acclimation
Temperature - 96 Hours

Effects of Sudden Temperature Change on Walleye
Juveniles Exposed to a Temperature Above Their
Acclimation Temperature

Percentage Survival of Walleye Juveniles Exposed

to Upper Lethal Temperature Levels for Each

Acclimation Temperature for 96 Hours

12
14

19

23

25

27

30

36

38

39

4l


31. Kelso, J. R. M. Conversion, Maintenance, and Assimilation for
Walleye, Stizostedion vitreum vitreum, as Affected by Size, Diet,
and Temperature. J. Fish. Res. Bd. Canada. 29:1181-1192,

August 1972.
32. Hile, R., and C. Juday. Bathymetric Distribution of Fish in Lakes

of the Northeastern Highlands, Wisconsin. Trans. Wisc. Acad. Sci.,
Arts & Letters. 33:147-187, 1941.

33. Ferguson, R. G. The Preferred Temperature of Fish and Their Mid-
summer Distribution in Temperate Lakes and Streams. J. Fish. Res.
Bd. Canada. 15(4):607-624, July 1958.

64


Table 3. PERCENTAGE HATCH OF WALLEYE EGGS FERTILIZED AT 6 DIFFERENT

TEMPERATURES AND INCUBATED AT 6 DIFFERENT TEMPERATURES

Fertilization

temperature, Incubation temperature, C
is 6.0 8.9 12.0 15.0 18.1 20.9
6.2 84.0 77.0 77.0 80.0 63.0 0.0
9.1 51.0 66.5 67.0 73.0 61.0 23.0
12.0 37.7 59.0 61.5 53.0 38.0 10.0
15.2 5.0 11.0 15.0 15.0 0.0 0.0
17.9 11.0 39.0 27.0 41.0 32.0 1.0
20.9 1.0 5.0 10.0 7.0 0.0 0.0

19


best egg survival in natural conditions occurred in years of warm water
temperatures and shorter incubation periods. Therefore, the effect of
higher temperature caused by electric generating power plants could

have both beneficial and detrimental effects on walleye survival.

The objective of the present investigation was to determine thermal
requirements for early life history stages of the walleye and sauger
and to provide a basis for the establishment of accurate water quality
criteria. These studies include the determination of lethal and sub-
lethal temperature effects on eggs, fry, and juveniles tested in the
laboratory at the University of Minnesota. The specific objectives of
the study were to determine: 1) optimum temperatures for egg and fry
survival; .2) optimum temperatures for juvenile growth; 3) effects of a
sudden temperature change on fry and juveniles; and 4) the upper lethal
temperatures for juveniles. Optimum temperatures for fertilization,
incubation, and fry survival were determined. Juvenile fish were
exposed to a series of constant temperatures to determine optimum
growth levels. Walleye fry and juveniles were also subjected to a
series of test temperatures to determine the effect of a temperature
change on survival. To conclude the study, walleye and sauger juveniles
were exposed to high temperatures to determine the upper lethal tempera-

tures after acclimation to a series of temperatures.

This study was funded by the Environmental Protection Agency (Project
No. 18050 PAB) and the Agricultural Experiment Station of the Univer-
sity of Minnesota.


9C Y= 1.5432 + +0157X, + +0130X, - +0190X, - +0328K,

+ +0288K, + +0103K, (2)

12 C Y = 1.6645 + +0076X, + +0102x, + +0137K, - -0141X,

- -0117%, + -0121X, (3)
15 ¢ Y = 1.6802 + 0025, + +0100X,, + -0238X, - -0130K,
- +0019, + -0161X, (4)
18 C Y = 1.6363 - +0027X, - -0069X, + +0097, + +0267%, (5)
= size in om
where Y 1og(Si2e-in am) 1063

X,-X. = dummy variables (see Appendix A, Tables 2 and 3)

tal
il}

Mean number of days to hatch.

The F-ratios calculated for each incubation temperature were as
follows (*significant at .05 level):
6C F= 2.51*
9C F = 27.40%
12 C F = 8,25*
15 Cc F = 8.47*
28 Cc F= .8151
Table 5 shows the size of the fry at the different temperatures cal-

culated from the regression equations.

With incubation temperatures of 6 C, 9 C, 12 C, and 15 C, the size of
the fry at hatch was consistently greater at the lower fertilization
temperatures, 6 and 9 C. At the incubation temperature of 18 C there
was no significant difference at the .05 level in the size of the fry

24


33.

34,

35.

Active walleye spawning occurs in the Montello River, Wisconsin
when water temperatures reach 5.6 C.

Priegel, Gordon R. Descriptors
1968. Lake Winnebago cousins. Wisc. WALLEYE
Conserv. Bull. 33(2): 24-25. SAUGER
WISCONSIN
INCUBATION

Walleye eggs will hatch in 21 days at water temperatures of 10.0-
12.8 C while sauger eggs will hatch in 13-15 days at the same
temperature.

Priegel, Gordon R. Descriptors
1969. The Lake Winnebago sauger. Age, SAUGER
growth, reproduction, food habits WISCONSIN
and early life history. Wisc. Dept. SPAWN
Nat. Res., Tech. Bull. 43, 63 p. INCUBATION

In 1965 sauger spawning occurred between May 2-9 when the tem-
perature ranged from 6.1-9.4 C. In 1966 the water temperature
ranged from 7.2-10.0 C but no spawning activity was observed. In
1967 spawning occurred from April 24 to May 6 when the water tem-
perature ranged from 7.8-11.1C. In a fish hatchery sauger eggs
hatched in 13-15 days at a water temperature of 10.6 C.

Priegel, Gordon R. Descriptors
1970. Reproduction and early life history WALLEYE
of the walleye in the Lake Winnebago WISCONSIN
region. Wisc. Dept. Nat. Res., Tech. SPAWN
Bull. 45, 105 p. INCUBATION

In the Lake Winnebago region, Wisconsin, walleyes were observed
spawning when water temperatures ranged between 2.2-15.6 Cc;
During peak spawning periods water temperatures were 5.6-7.8 G.
The following tables show the temperature (C) criteria for spawn-
ing and incubation of walleyes and eggs in the Lake Winnebago

86


SECTION IV

MATERIALS AND METHODS

EXPERIMENTAL FISH STOCK

Adult walleyes were secured from Little Cutfoot Sioux Lake and Upper
Red Lake in the spring of 1971 and 1972. The fish were captured with
trapnets by the Minnesota Department of Natural Resources during the
spawning run. Adult saugers were taken from Lake Winnebago, Wisconsin
in 1972 and from the Mississippi River, below Lock and Dam #3 in Red
Wing during the spring of 1972 and 1973. The saugers from Lake Win-
nebago were captured with trapnets by the Wisconsin Department of
Natural Resources during the spawning period. Fish from the Missis-
sippi River were collected with a boom shocker by the Minnesota
Department of Natural Resources during the spawning run. Adult fish
were taken 1 to 2 days prior to full ripeness and transported to the
laboratory at the University of Minnesota in 100 gallon stock tanks

aerated with compressed air.

Juvenile walleyes were secured from natural rearing ponds stocked by
the Minnesota Department of Natural Resources. These fish were cap-
tured in July and August of 1971 and 1972 with seine nets and small-
mesh trapnets. Juvenile saugers were collected from Lake Pepin,
Minnesota with a seining net during the months of July and August 1973.

EXPERIMENTAL APPARATUS

Apparatus used for thermal tests consisted of six polyethylene head
tanks, each with 114 liters capacity. The temperature of the water
entering the head tanks was 10 C for experiments conducted above 10
C. Chilled water at 4 C was supplied in head tanks in experiments

run at less than 10 C. The water was aerated in each head tank to


TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)

7. REPORT NO. 2. 3. RECIPIENT’S ACCESSION NO.
EPA-660/3-75-017
4, TITLE AND SUBTITLE iS, REPORT OATE
Temperature Effects on Eggs and Fry of Percoid July 1974 completion date
Fishes 6. PERFORMING ORGANIZATION CODE
‘V7 AUTHOR(S) |8. PERFORMING ORGANIZATION REPORT NO.

Lloyd L. Smith, Jr. and Walter M. Koenst

19, PERFORMING a NAME AND ADDRESS 10. PROGRAM ELEMENT NO.
epartment of Entomology, Fisheries and Wildlife

University of Minnesota a NO
St Paul MN 55101 : "
R-800704
12, SPONSORING AGENCY NAME AND ADORESS. 13, TYPE OF REPORT AND PERIOD COVERED
U.S. Environmental Protection Agency Final

National Water Quality Laboratory 74. SPONSORING AGENCY CODE

6201 Congdon Boulevard
Duluth MN 55804
15, SUPPLEMENTARY NOTES

76. ABSTRACT

Temperature effects on the early life history stages of the walleye (Stizostedion|
vitreum vitreum (Mitchill)) and sauger (Stizostedion canadense (Smith)) were examined.
Walleye eggs and fry were exposed to six temperatures (6-21 C) for effects on fer-
tilization, incubation, and fry survival. Mature sauger were held and eggs were
fertilized at four temperatures (9-18 C). Both species were incubated at 6-21 C.
Sauger fry survival was also tested at 6-21 C. Optimum fertilization temperatures
were 6-12 C for walleye and 9-15 C for sauger. Optimum incubation temperatures were
12-15 C for both walleye and sauger. A sharp drop or rise in temperature had no great
effect on walleye fry and juvenile survival except when the upper lethal or lower
lethal temperature was approached. Optimum temperature for juvenile walleye and sau-
ger growth was 22 C. Upper lethal temperatures for walleye juveniles were determined
for acclimation temperatures at 2 C intervals between 8-26 C. The upper lethal tem-
perature of walleye juveniles was 27.0-31.6 C, depending on acclimation. The upper
lethal temperature of sauger acclimated to 10-26 C was 26.6-30.4 C. There was little
temperature difference (1-2 C) between 100% survival and no survival.

17 KEY WORDS AND DOCUMENT ANALYSIS
ha DESCRIPTORS b.IDENTIFIERS/OPEN ENDED TERMS |c. COSAT! Field/Group
Sauger*, walleye*, environmental effects*, temperature tolerance, 6

growth rates*, fish eggs*, fish larvae*, acclimation

juvenile fishes, growth stages, water
pollution effects, cold resistance, heat

resistance

8. DISTRIBUTION STATEMENT 18, SECURITY CLASS (This Report) 21. NO. OF PAGES
unclassified 99

Release unlimited 20. SECURITY CLASS (This page) 22. PRICE
unclassified

. -
PA Form 2220-1 (9-73) fe U.S. GOVERNMENT PRINTING OFFICE: 1975~698- 447/139 REGION 10



temperature standards in natural waters must be adjusted for seasonal
changes in requirements of the fish and that maximum temperatures not
causing death are above the optimum levels for adequate population
maintenance. Temperature maxima insuring natural population safety
will probably be 3 to 4 degrees below the upper lethal temperature
found for unfed fish. Short periods of excess heat could be fatal
to the population if permitted levels are too close to the lethal

level.

60


Appendix A, Table 1
THE EXPECTED VALUES OF PERCENTAGE HATCH OF WALLEYE EGGS
FERTILIZED AT SIX DIFFERENT TEMPERATURES AND INCUBATED AT
SIX DIFFERENT TEMPERATURES
The Observed Values Are Shown on Table 3 in The Main Text

Nominal

fertilization Incubation temperature,

temperature, Cc
¢ 6 9 12 15 18 21
6 64.29 77.27 78.48 79.80 66.83 14.34
9 55.25 69.98 71.43 73.04 58.02 10.30
12 24.71 56.25 57.97 59.90 43.26 5.95
15 5.77 10.37 11.04 11.84 6.42 0.57
18 22,15 34.95 36.56 38.43 48.32 2.58
21 2.82 5.20 5.56 5.99 3.15 0.27

66


The chambers used for tests on juveniles were identical to the fry
chambers except that a higher flow rate was used. Flow rates were
controlled with a utility clamp and were adjusted according to the
temperature level with flows at higher temperatures of about 2 liters/
min. Each chamber was lighted with a 40 watt incandescent light
placed approximately 2 feet from the water surface and the photoperiod
was adjusted bi-monthly to follow the natural environmental day length
cycles.

TEST WATER CONDITIONS

The incubation, fry survival, and growth experiments were conducted at
six constant temperatures. The temperature, pH, oxygen concentration,
and total alkalinity for the tests are shown in Table 1. The tempera-
ture was measured daily with a total immersion thermometer graduated
to 0.1 C. A 24 channel temperature recorder was used to monitor tem-
perature variation through the tests. Dissolved oxygen was

measured bi-weekly with the azide modification of the Winkler method
(apna?) . Total alkalinity was determined weekly as mg/liter Caco,
by the brom-cresol method (Dobie and Moyle?) . Temperatures fluctuated
only slightly, the pH averaged 8.00, the Oo concentration was 5.8
mg/liter or greater depending on the temperature, and the total alka-
linity averaged 225 mg/liter.

Test water was taken from the laboratory well which had a pH at 10 C
of 7.5. A complete analysis of water was made by the Minnesota Depart-
ment of Health, Division of Environmental Sanitation (Table 2).

ACCLIMATION PROCEDURE

The adult fish taken in the field at 5-10 C were acclimated to six
test temperatures in the laboratory (6, 9, 12, 15, 18, and 21 C)
before they were stripped for eggs. When brought into the laboratory
the adults were placed in 335 gallon holding tanks at the temperature
of capture. Twelve hours later temperatures were changed in 24 hours

11


randomly removed with an eye dropper and placed in the incubation
chambers. Eggs that were small and opaque were discarded. The number
of opaque eggs varied from 0 to 80% with no relation to temperature
of fertilization.

EGG TEST PROCEDURE

Eggs were counted, dead eggs were removed, and mortality counts were
recorded daily. Only eggs that had turned white were counted as dead.
Live eggs were not handled and remained in the incubation chambers
until hatched.

FRY TEST PROCEDURE

Upon hatching fry were removed with a glass tube and gradually trans-
ferred to the fry chambers. Fry were sampled for size determinations
each day after hatching started. Ten percent of the fry from each
day's hatch were randomly removed and preserved in 5% formalin, and
100 fry were placed in each fry chamber for survival tests. All fry
were fed twice a day with natural plankton which consisted mostly of
copepods and once a day with brine shrimp. Black plastic sheets were
taped to the outside walls of all aquaria since it was found that fry
in chambers without the black walls did not swim freely but clung to
the sides of the chamber without feeding and eventually died. Fry in
chambers with black walls swam freely and fed well.

16


HATCH

PERCENT

Figure 8.

too r

FERTILIZATION TEMPERATURE

9°c

sor

2or

ou

6 9 i218 le 2I

INCUBATION TEMPERATURE (°C)

The combined effect of fertilization temperature and incuba-
tion temperature on the hatchability of sauger eggs. Each
line represents the percentage hatch of eggs fertilized at
one of four temperatures and incubated at six temperatures.

45


41.

42.

walleyes. Eggs were held at a constant temperature of 12.2 C; by
the 10th day eggs are eyed and start hatching in 20 days.

Steucke, Erwin W. Descriptors

1968. Optimum temperatures for hatching WALLEYE
northern pike and walleye eggs. WISCONSIN
Proc. North Central Warm-Water Fish INCUBATION

Culture Workshop, Iowa Coop. Fish.

Unit, 1968: 32-34.
Walleye eggs were incubated at different test temperatures
ranging from 10.0-23.9 C. The temperature maintenance during the
test was +0.28 C. At 19.4 C, 67% of the eggs hatched. Walleye
eggs were then incubated at 21.7 C and 23.9 C. These hatched in
5 days but died immediately after hatching. It was concluded that
16.7-19.4 C was the best temperature for hatching walleye eggs.
It was also concluded that based on 32 F, it took an average

number of 238 degree-days for walleye eggs to hatch.

Walburg, Charles H. , Descriptors
1972. Some factors associated with fluctuation SAUGER
in year-class strength of sauger, Lewis S. DAKOTA

and Clark Lake, South Dakota. Trans. INCUBATION
Amer. Fish. Soc. 101(2): 311-316. YEAR-CLASS
STRENGTH

Saugers spawned in the Missouri River when water temperatures
reached 6.1 C. At an average water temperature of 8.7 C the
embryo incubation period for saugers is 21 days. It was found that
June reservoir water temperature, along with water level} fluctua-
tion over the spawning grounds and the reservoir exchange rate
account for 86% of the variability in year-class strength. Fewer
fish were lost when June water temperatures averaged near 21 C.

At cooler temperatures the growth was slower and fry were more

subject to current loss in the discharge.

90


18 C; and 5, 5, and 6 days at 21 C. Time to first hatch (30 days),
median hatch (34 days), and to the completion of hatch (49 days) was
longest at the lowest temperature, 6 C, and decreased exponentially to
a minimum of 5 days to first hatch, 5 days to median hatch, and 6 days
to the completion of hatch at the highest temperature, 21 C.

The mean size of the fry at hatch varied from 6.0 mm at 6 C to 7.8 m
at 12 C. The mean size of the fry at hatch was greatest (7.2-7.8 mm)
at the intermediate temperatures, 9-18 C, and least at the temperature
extremes, 6 and 21 C, where the mean size of the fry were 6.0 and 6.6

mm, respectively.

The survival of walleye fry from hatch to resorbtion of the yolk sac
was high (78-98%) at all temperatures except 6 C. At this temperature
the fry never resorbed their yolk sac completely and eventually died
about 30 days after hatching.

Total survival of walleye fry from hatch to the juvenile stage was very
low. All fry died at the four lowest temperatures and there was only
1% survival at 18 C. At 21, 8% of the fry survived to the juvenile
stage. The fry at 6, 9, and 12 C never accepted food, but the fry at
the higher temperatures, 15, 18, and 21 C,did accept food. A few
walleye fry at 15 C accepted food, at 18 C about 50% fed, and at 21 C
about 75% of the fry fed on plankton.

28


Table 1. TEMPERATURE, pH, DISSOLVED OXYGEN (0,),
AND TOTAL ALKALINITY OF TEMPERATURE EXPERIMENTS

Observed temperature

Nominal Standard Mean Mean
temperature, Mean, deviation, oO, TA
Test c c ¢ pH___mg/1__mg/1
Walleye 6 6.2 40.32 - 8.1 236
adult ac~ 9 9.1 40.11 - 7.9 232
climation 12 12.0 +0.14 - 8.0 225
and ferti- 15 15.2 40.27 - 7.4 234
lization 18 17.9 40.09 - 7.2 237
24 20.9 $0.12 - 7.9 215

Sauger
adult ac- 9 9.2 +0.16 - 7.8 225
climation 12 11.9 +0.10 - 7.9 230
and ferti- 15 15.0 40.12 - 7.5 215
lization 18 18.2 40.21 - 8.0 230
Walleye and sauger 6 6.0 +0.22 8.0 8.0 232
egg incubation 9 8.9 40.26 7.9 71 232
and fry 12 12.0 +0.07 8.0 7.6 227
survival 15 15.0 +0.19 8.0 7.3 215
18 18.1 40.21 8.0 7.5 230
21 20.9 40.22 8.1 8.4 230
Walleye 16 16.3 40.16 8.1 9.4 238
juvenile 21 21.1 40.24 8.2 8.3 236
growth I 25 25.2 0.26 8.2 8.6 238

12


16, and 18 C and exposed to 29 C was 0.0, 12.5, and 25.0%, respectively.
The percentage survival at 28 C for the same acclimation temperatures
was 87.5, 100, and 100%, respectively. The median survival times for
the exposure to 29 C were 32, 29, and 31 minutes for the fish accli-
mated to 14, 16, and 18 C. The median survival times for the same
acclimation temperature and exposure to 30 C was 16, 18, and 19 minutes,
respectively. Juvenile fish acclimated to 20 and 22 C had an upper
lethal temperature of 29.5 and 29.9 C. Survival was 0% and 25.0% at

30 C and 100% at 29 C for both acclimation temperatures (20 and 22 C).
The median survival times for the fish acclimated to 20 and 22 C was
1328 and 1512 minutes for exposure to 30 C and 122 and 545 minutes

for exposure to 31. Fish acclimated to 24 and 26 C had an upper
lethal temperature of 30.4 C. At a temperature of 31 C no fish sur-
vived from both acclimation temperatures and 87.5% of the fish sur-
vived at a temperature of 30 C for both acclimation temperatures.

The median survival times for fish acclimated to 24 and 26 C and ex-
posed to 31 C was 1242 and 690 minutes, respectively. The median
survival times for exposure to 32 C was 348 minutes for fish accli-
mated to 24 C and 246 minutes for fish acclimated to 26 C.

56


No.

12

13

14

15

16

1

Percentage Hatch of Sauger Eggs Fertilized at
Four Temperatures and Incubated at Six Temper-
atures

The Effect of Six Constant Temperatures on Sauger
Eggs and Fry

Growth of Sauger Juveniles for 36 Days at Differ-
ent Temperatures

Percentage Survival of Sauger Juveniles Acclimated
to 10 - 26 C and Exposed to Higher Temperatures
for 96 Hours

Median Survival Time of Juvenile Saugers Acclima-
ted to 10 - 26 C and Exposed to Upper Lethal

Temperatures

46

48

51

54

55


37.

38.

was found that walleyes were active in the range from 15.0-18.3 C.
It was suggested that it was unlikely that temperature preference
was the reason for movement into deeper water, since it was found
that August water temperatures at 5 to 10 meters were usually
between 16.1-18.3 C and the surface temperature rarely exceeded
18.9 C. An alternative reason for movement into deeper water

was suggested to be the pursuit of food organisms such as ciscoes.

Regier, Henry A., Vernon C. Applegate, and Descriptors
Richard A. Ryder WALLEYE
1969. The ecology and management of the SAUGER
walleye in western Lake Erie. Great LAKE ERIE

Lakes Fish. Comm. Tech. Rep. 15, 101 p. DISTRIBUTION
Walleye reportedly prefers a temperature of about 21.1-22.2 C in
summer, but some resident populations in rivers (Illinois) tol-
erate water temperatures as high as 30 C for extended periods.
From all available information it appeared to the authors that
light intensity is a more important factor in determining depths
selected by walleyes in the summer than water temperature. Based
on the geographical distribution of saugers and walleyes, it was
suspected that saugers are less tolerant to low temperatures and
slightly more tolerant to high temperatures than the walleye since

saugers occur further southwest and do not occur as far north.

Schumann, George C. Descriptors
1964. The effect of abnormal temperatures on WALLEYE
the spawning and developmental success WISCONSIN

of eggs from the North American walleye. SPAWN

Transl. from Osterreichs Fischerei, May

1964(5): 85-87, by Dieter N. Busch,

U.S. Bur. Comm. Fish., Sandusky, Ohio.
In northern Wisconsin it was found that the walleye consistently
spawns at water temperatures from 5-10 C with the largest walleyes

reaching the spawning grounds first. When temperatures quickly

88


In both curves 22 C was the optimum temperature for growth of walleye

juveniles but the optimum temperature range can be extended to include
19-25 C.

In the 1972 study mortality occurred at the higher temperature levels.
At 28 C, 40% of the fish died during the study and at 24 and 26 C,
20% of the fish died.

33


9€

Table 8. EFFECTS OF TEMPERATURE CHANGE ON WALLEYE FRY INCUBATED AND REARED
AT 6 C, 11 C, AND 21 C - 72 HOURS

Age of fry Rearing Test Temperature Corrected

Number after hatch, temperature, temperature, change, Survival survival?!
of fish days c Cc c A A
10 5 6.0 6.0 0 90 100
10 5 6.0 11.1 +5.1 90 100
10 5 6.0 15.9 49.9 100 1i1
10 5 6.0 21.1 415.1 50 56
50 2° 11.1 11.1 te) 98 100
50 2 11.1 6.0 -5.1 56 58
50 2 11.1 15.9 +4.8 100 102
50 2 11.1 21.1 +10.0 76 78
50 7 21.1 21.1 fe) 66 100
50 7 21.1 6.0 -15,1 0 0
50 7 21.1 11.1 -10.0 60 91
50 7 21.1 15.9 5.2 72 109

al Control corrected to 100% and other temperature levels adjusted accordingly.