Muscular Fatigue and Mortality in Troll-CaughtChinook Salmon (Oncorkynckws tskawytscka)r' z' t

By RosEnr R. Penrsna aNo Eocan C. Brl.crb

ABSTRACT

Blood samples were analyzed for lactic acid from 66 troll caught chinook salmon afterfrom zero to 70s/+ hours of rest. Fish were held in a live box aboard a trolling vessel. Duringthe course of the experiment 22 individuals died. Analysis of these data indicate a generalresponse of blood lactic acid comparable with results of other experiments. The typicalresponse is a gradual increase of blood lactic acid to high levels in the third and fourth hours,followed by a general decline. Death is strongly associated with high blood lactic acid. Thelevel of lactic acid response is not significantly increased with more than 10 minutes ofvigorous exercise nor is it significantly affected by the size of the fish within the rangessampled in this experiment. Mortality rate is estimated at 7l% with 95 percent binomialconfidence limits of 4OVo and 86Vo.

INTRODUCTION

THar plsu orp following severe exertion was first shown by von Buddenbrock

(1938), working with cod (Gqdus morrhua) and the dab (Platessa limanda).

Huntsman (1938) further discussed the problem in a review article and concluded

that struggling of fish in captivity led to death. Secondat and Diaz (1942) have

also shown that tench (Tinca tinca) may die following severe exercise. In 1956,

death of Pacific salmon following severe muscular exercise was demonstrated by

Bates and Vinsonhaler (1957) for smolt chinook salmon (O. tshawytscha), and

by Black (1957c) working on two-year-old sockeye salmon (O. nerka) acclimatedand exercised in sea water. Paulik and Delacy (1958) have reported a reductionin survival time of mature sockeye salmon after strenuous activity in fresh water.Bates and Vinsonhaler also noted death following severe muscular exercise ofimmature striped bass (Roccus saxatalis) and shad (Alosa sapidissima). Presum-ably death in some way resulted from muscular exercise.

Von Buddenbrock (1938) noted the presence of lactic acid in the blood andattributed death to a suppression of oxygen transport ability, i.e. to asphyxiation.Secondat andDiaz (1942) and Black (1957a, b, c) demonstrated the presence ofhigh concentrations of lactic acid in the blood of fish following severe exercise.These latter authors standardized exercise as maximum swimming effort sustainedfor 15 minutes. They also demonstrated that blood lactic acid levels continue torise after the exercise period, reaching a maximum during the flrst I or 2 hours ofpost-exercise rest, and then may remain at a high level for a subsequent 2 ta 6hours.

'Received for publ icat ion February I 9. I 958.2Contribution from the Alaska Department of Fish and Game, Juneau, Alaska, and fromthe Department of Physiology and the Institute of Fisheries, University of British Columbia,Vancouver. Canada.

sThis project was supported in part by a grant-in-aid from the National Research Councilof Canada, and by the British Columbia Electric Company, Vancouver, Canada.'Senior Biologist, Alaska Department of Fish and Game, Juneau, Alaska; GraduateStudent, Institute of Fisheries, University of British Columbia, Vancouver, Canada.

"Associate Professor, Department of Physiology, University of British Columbia, Van-couver, Canada.

95J. Frsn. REs. Bo. CaNeoe, 16(1), 1959.Printed in Canada.

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96 JouRNAL FTsHERTES RESEARcH BoARD oF cANADA, vor-. 16, No. 1, 1959

At the present time the precise cause of death in fishes following severemuscular activity is not known; Black (1958) presents a review of the availableevidence. Whatever the mechanism involved, the efiects of fatigue upon survivalare an important consideration in studies involving tagging or in management ofa stock of fish by a size restriction. Increase of lactic acid concentration in theblood appears to be directly correlated with, if not a causative agent of, deathafter severe muscular exertion. Death due to fatigue is delayed (Black 7957c;Paulik and Delacy, 1958) and the survival of an individual fish cannot be predictedfrom external appearances at the time of catching. In view of these observationsthe present experiment was designed to examine the delayed efiects of commercialfishing by troll gear on the survival of released chinook salmon. Levels of lacticacid in the blood appear to provide a good indicator of the state of well-being ofthe fish following exercise; thus, it was chosen as the dependent variable. Theauthors also wished to determine to what extent a fish can be exercised withoutmortality as well as the differences in effects of exercise on di-fferent sized fish.Specimens obtained aboard a commercial troller offer such opportunity, as bothtime spent on the gear and size of individual fish vary considerably in a normalflshing operation.

The experiment was conducted during the latter half of August, 1957, onfishing grounds at approximately 58' 40'N., 138o 15'W., about 15 miles off CapeFairweather, Alaska.

METHODS AND MATERIALS

Chinook salmon were obtained aboard a commercial trolling vessel. Allelements of catching, i.e. p7ace, depth, and gear used were left to the discretion ofthe Captain in order to test survival of fish caught under strictly commercial fishingconditions. Six lines were fished, each line bearing from 8 to 12 lures. Lures usedwere a standard brand of commercial spoons with No. 7 or No. 8 hooks.

Every effort was made to record the time each fish was on the line; this wascomplicated in several instances by fish biting other lures on the same line, necessi-tating a guess as to which was the original fish. The time statistic is referred toas the "exercise time". Fish used for the experiment were landed and placed ina live box, then the lure was removed.

Rested, unexercised fish r.vere impossible to obtain for a standard base line.Lactic acid values for fish immediately after exercise were obtained by sampling 6individuals as soon as they were landed. Two of these were bleeding from gillinjuries. All fish held were in what appeared to be good condition and bore novisible signs of damage to the gills, eyes or other vital organs. In other words, fishtested were selected for maximum survival as judged from external appearances,and would have been considered fit for tagging.

The live box contained approximately 750litres (200 gallons) of sea waterand was lined with polyethylene sheet. Horizontal dimensions were approximately3.0 by 5.5 feet and water depth was maintained at approximately 1.5 feet. Freshsea water was continually supplied by means of a mechanical pump at a rate ofapproximately 75 litres (20 gallons) per minute.

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PARKER AND BLACK: FATIGUE IN TROLL-CAUGHT SALMON 97

Individual fish were coded by using a stainless cattle tag bearing a serialnumber, applied dorsally to the caudal fin. Fish were allowed to rest in the livebox for predetermined amounts of time, the objective being to obtain samples overa 10 hour range. In no case were more than 4 f,sh held in the live box at onetime.

Surface water supplied to the live box was between 14" and 15"C. Fishingtook place over depths ranging from 70 to 80 metres (35-40 fathoms) and themajority of fish took lures at or below 30 metres (15 fathoms). Several bathyther-mograph casts were made during the course of the experiment. Fish utilizedgenerally came from water of a temperature between 7" and 10'C. The possible

significance of this change in temperature to blood lactic acid levels is not known.In general, the rate of metabolism would be increased by a change of this magnitudebut difiusion rates into and out of the blood would also increase. The interactionof these changes cannot, at present, be predicted.

The fish were disturbed as little as possible during the resting period; however,motion of the vessel and vibration of the propulsion engine could not be controlled.When fish were first placed in the live box, they generally appeared lively andwould explore the tank. This activity lasted but a few minutes and was followedby quiescence. Often fish would fail to maintain equilibrium and float passivelyupside down, either at the surface or on the bottom. This condition usuallyappeared after one half hour of rest, although some individuals would lie overwhen first introduced into the tank. Some fish righted themselves after variousamounts of rest, others failed entirely to do so. Similar behaviour was observed bythe second author in studies with yearling rainbow trout and two-year-old sockeyesalmon.

Judging from the appearance of the gonads, and from results of previousstudies in the same area (Parker and Kirkness, 1956), fish used in the presentexperiment were not in their ultimate year. All fish taken were feeding, many hadgorged stomachs. Thus the present experiment contrasts with that of Paulik andDelacy (1958) who used mature non-feeding flsh in fresh water.

At the end of a selected time period, if the particular fish did not die, it wasstunned by a blow on the head and blood was immediately drawn from the heart.In case the flsh died prematurely, a blood sample was taken before clotting andbefore rigor mortis. At the time of stunning the "apparent condition" of the fishwas subjectively evaluated and recorded.

After withdrawing the blood sample the fish was again examined for externalinjury, and fork length to the nearest half inch was recorded.

One millilitre of blood was drawn from the heart into a 2-ntl Luer syringecoaied with mineral oil and rinsed with heparin solution. The sample wasimmediately expelled into a polyethylene bottle containing 9 nt. of. lO% trichlor-acetic acid. This mixture was filtered within the hour and the filtrate, collected ina polyethylene bottle, placed on ice in the fish hold. The samples were taken tothe Department of Physiology of the University of British Columbia in Septemberand the analyses for lactic acid by the method of Barker and Summerson (Hawk,

Oser, and Summerson, 1949) werc carried out by the second author in October.

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98 JoURNAL FTSHERTES REsEARcH BoARD oF cANADA. vor-. 16. No. l. 1959

250

Time in hours from hookingFrc. 1. Blood levels of lactic acid of chinook salmon following capture bytrolling. The averages are intercepted horizontally by lines representing thetime range of the group, and vertically by a line representing the range in

lactic acid. Single observations are notated by a circle.

The values of lactic acid are expressed as milligrams of lactic acid per 100millilitres of whole blood (mg% ).

RESULTS

A total of 66 samples was obtained, which included fish given from zero upto lO)! hours of rest. Within the total sample, the exercise time varied from 3 to30 minutes, and the fork length of individuals varied from 38 to 85 cm (15.0 to33.5 inches). These data are presented in the appendix. The total sample wasfirst grouped according to half-hour time periods, zero time being taken from thestart of exercise period (at hooking). Within these groups mean lactic acid levelrn mg7o and mean time were computed. These data, together with the within-groupranges are graphically presented in Fig. 1 and recorded in Table L

A large variation is noted in these samples and it was desirable to test forsignificance not only of curvilinearity but also the effects of size and exercisedifferences in contributing to systematic error. From an inspection of Fig. 1, itappears that the means of observations (exclusive of the four highest time periods)might best be described by a parabolaG. The four individuals representing the four

uWe do not consider a parabola in itself to have any significance, i.e. the choice was oneof statistical convenience.

E 2 O Ooo

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PARKER AND BLACK: FATICUE IN TROLL-CAUGHT SALMON

Tesrn I. Summary of data for total time of exercise and holding in live box, and bloodlevels of lactic acid in Chinook salmon.

99

Numberof flsh

Time Time, minutesperiodhours Range Mean

Blood lactic acid, mg Vo

Range Mean

668

t 075J

2J

II6200I01I00I

0- 0 .50.5-1.01.0-1.51.5-2.02.0-2.52.5-3.03.0-3.53.54.04.04.54.5-5.05.0-5.55.5-6.06.0-6.56.5-7.07.0-7.57.5-8.08.0-8.58.5-9.09.0-9.59.5-10.0

10.0-10.510.5-1 1.0

9-203 5-5565-8891-112

126-150160-180I 83-200220-235'ol.?'o

333-35437 5-382

3 8.8-101.09.6-240.0

108.0-202.083.2-220.0

125.V216.Ot34.0-226.087.3-216.0

182.0-209.013 6.0-186.0

oo.k-iss.o26.0-11,3.0

7 4467498

1 3 81691902282612753 1 5Jz+o

378

64.620.150.163.r77.985.67 t . 595.557.760.072.04 1 . 869.5

zoq'.0

zg'.080.5

463

\;o562

'ab'.t

highest time periods were excluded from the data for these calculations, i.e. or:.dythe time period from 0 to 6.5 is considered. For statistical convenience the datawere coded into groups (Table II).

For covariance analysis of size, fork lengths (L, in inches) were first con-verted into estimated weights (W, in pounds dressed) by the empirical formula ofParker and Kirkness (1956):

'w - u'u354

This conversion was thought necessary as weight represents mass of fish producinglactic acid better than a linear dimension. Individuals were classified into threeweight groups: (l) 2700 grams (6.0 pounds) or less; (2) 2700 to 5500 grams(6.1-12.0 pounds); (3) more than 5500 grams (212.1 pounds). Individualswere also classified into two groups according to recorded exercise time: (1) 10minutes and less, (2) lI minutes and more. A further classification was desirableto test for any correlation between high lactic acid levels and death. This classifica-tion is arbitrary in that no knowledge is available as to the probable fate ofindividuals killed for blood samples. The entire classification system is presentedin Table II.

A second degree polynomial was fitted to the total sample by the method ofmultiple regression (Snedecor, 1950), yielding, when converted to ordinary units,the equation'

v - 6.4r+ 1.84gx - o.o67xzThe standard error of estimate, &.12, is 4.365 cells of Y or 43.65 mgVo. The cal-culated curve together with the coded cells of empirical data and their frequencyare presented in Fig. 2. A test for significance of departure from linear regression

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100 JOURNAL FISHERIES RESEARCH BOARD OF CANADA, VOL. 16, NO. 1, 1959

Tesrr II. Coding and grouping of time held after hooking (X) and blood levels of lacticacid (Y).

X = intervals of r/q hoLt from time of hooking to time of death.Y = intervals of 10 mg Va lactic acid concentration.

Exercise groups

Less than 10 minutes More than 10 minutes

Alive Dead Alive Dead

YYX

Fish less than 2700 grams (6 lb)2 t 3 1 7 2 r1 6 3 2 4 9 2 2

8 2 2 9 1 , 621 18 11 2323 14 lZ 20

13 2215 2 l17 1.9

I345778

79

1 0I J

1 29

1 61 49

1 6

1Z1 31 9

123456789

t 0

Fish of 2700 to 5500 grams (6-12 Ib)7 4

41 574t9201 61 6l b

202093

12345o789

1 01 1l 21 3

I^5o7

4 1 513 202 3 725 12

5 1 19 1 8

1 6 L 9

7 1 7t 0 1 710 2213 221 8 1 4

77

1 8L AA A

a t

z6Fish of more than 5500 Srams (12 Ib)

9t 1

12J/5b

5o

71 01,2L J

I J

1 81 81.31 ' 7

1 8

t 9 1 91 8 I 1 1

2 61.4 15

gave a significant "F" value of 34.0, d.f. - 1, 59. The correlation between i and Y

(estimated mean legression and observed values) is R - 0.617, where significance

ot P.61, with three vadables is at R - 0.410.Analysis of covariance was used to test for systematic error due to both size

and exercise time. Size proved non-significant, "F" - 0.3, d.f.2,48; exelcise time

was also non-significant, "F" -2.5, d.f. 1,48 (P.ou: 4.04). A significant dif ier-

ence was obtained between live fish and flsh which died, "p" : 13.8, d.f. 1, 48"

A regression line was calculated for the dead group only obtaining the equation:

9 - z .sso + 2.863x- 0.111X2, ss. r2:2 '68I -

This curve is plotted as a dashed line in Fig.2 and is seen to lie above the regression

line of the total sample.As previously noted, 22 fish died during the course of the experiments (Table

II). This number does not, however, represent any estimate of mortality per se in

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PARKER AND BLACK: FATIGUE IN TROLL.CAUGHT SALMON 1 0 1

=()o.9C)o

o(t(|)q)

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Coded time intervols of quorter hours?. Calculated parabola (solid line) from coded blood levels of lacticin quarter-hour time periods from hookine. See text and Table II.

Solid line, all data; dashed line, dead only.

that individuals were also killed, and no objective measurements of their chancesfor survival in lieu of sampling are available. This difficulty may be overcome bymaking an assumption that at any time period, fish killed were a random sample offish surviving to that period. The validity of this assumption appears to dependupon unbiased determination of which fish to kill, a condition thought to be satisfiedin that the period of post-exercise rest for each individual was determined prior tocatching. Calculation of point estimates and 95 percent binomial confidence limitsare presented in Table III. Instantaneous mortality rates7 (i ) for each time periodwere computed from the number dying and the number killed during a period fromthe number surviving the preceding period. variance of (i), sa2, is estimated byso': so2/p2 (Deming, 1943, p.45), where p is the estimated probability of sur-vival for each period. Instantaneous mortality rates and their variances werethen accumulated for each successive period. Confidence limits of accumulatedi (I) for each successive time period, denoted as I, i, were estimated from thebinomial approximation. At the 95 percent level,-I', Ts:I1 -+ l.96 sr,. Absolutemortality rates (m) were calculated by the relationship m - 1- e-r yielding anestimate of observed mortality rate (0.71) and an estimate of the magnitude of

lnstantaneous mortality rate (i) = log" N, - log" N, where N, denotes corrected totalof fish surviving period 1 and N, denotes fiih survivin! peiod, 2. N, - N, --nrh avirg.

-""

Frc.acid

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N

Teern III. Schedule of calculations of mortalitv estimates (see text).

Cumulative mortality ratesTime

period(t)(hours)

Survivors Deaths(d)

I t Instantaneous Total to end of periodHeld Killed Ditr. I t I r m t m t m t

0-11 a

z-J

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4-55-66-77*8

t 21,1

J

326z0

66543 61 t

l 7I J

64

q

d

zts(-

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trla

@

P

o

P

E

o

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!-

t

544 lJ J

2 l1 57I

4

059̂

2L0I

00 .1301 ,0 .31850.21130.143 I0.r542

00.2877

c

00.01600.23 180.3 598o.44330.48720.48720.5095

b

00 .13010.44860.65990.80300.95720.95721.2449

,o.24420.66540.9600t .16271.42721.42721.9803

00.0160.2070.3020.3 580.3 850.3 850.400

d,

00 .1220.3620.483o.5520.6160 .616o.71,2

00 .2160.4860.6170.6870.7 600.7600.862

aLn 41

L t -

S t r : r :

- Ln 36 - 0.1301 - i - instantaneous mortalitv rate for the second time period.n

't,h whete I = the cumulative instantaneous rates to include any time period n.

2rL

\'/-l si, i I , , I , : I ,+1.96 sy,, which estimates theg5Vo binomial confldence interval.

om , : ! - e

', = total mortality rate including time period l.

S , D-d : ---- r

p " 4 1 X 3 6 '

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PARKER AND BLACK: FATIGUE IN TROLL-CAUGHT SALMON

expected moftality rate (0.40 to 0.86) for fish held under similar conditions for8 hours.

The results are summarized as follows:l. Blood levels of lactic acid rise from a mean level of less than 60 mgVo to an

order of magnitude of 180 mgvo during the first three hours from hooking. Thesehigh levels persisted through the fourth hour and then declined toward normal.

2. The magnitude of this general response was not significantly correlated withthe size of the individual.

3. The general response was precipitated by less than 10 minutes of strugglingand further time on the troll gear did not significantly alter the degree of response.

4. Death of individuals was significantly associated with high blood levels oflactic acid.

5. Mortality of the experimental lot of fish was estimated to be 71 Vo. and the95 percent binomial confidence limits indicate an expected mortality between 4OVoand 86% for uninjured troll-caught chinook salmon subjected to similar treatment.

The large variation in degree of lactic acid response is thought to reflectindividual variation in respect to muscle glycogen level due to either previousenvironmental experience or genotypic differences, as well as a variable degree of,exertion on the troll gear.

DISCUSSION AND CONCLUSIONS

Black and Barrett (1957), working with trout (salmo clarki and s. gairdneri),,demonstrated that blood lactic acid increases as a result of handling. However,these responses were much lower (highest response approximately 55 mg% ) thanlevels noted by Black (1957a) for 15 minutes of forced exercise (5. gairdneri,above 140 mg%).

chinook held in the live box were generally quiescent; many were completelyunresponsive to normal stimuli as evidenced by loss of equilibrium. Further, adirect comparison with Black's (1957c) experimental sockeye shows a similarsequence of events although the details contrast. These experiments are comparedin Table IV.

Teelr IV. Compariso!_of, Tglllliry dara for Sti"pgF (.this paper) and sockeye (Black,j * . . r . t n . t t "Oa

Chinook SockeyeWater temperatureNumber exercisedNumber dyingWeight, averageTime to death, averageLactic acid just after exercise, averageLactic acid at death, average

103

1 5 0 C662236a0 g (8 .0 lb )169 minutes64.6 mgVo189 mS Vo

20act 95

198 S Q ounces)90 minutes103 me%240 mgVo

Since lactic acid arises from hydrolysis of muscle glycogen in the absence ofor at low concentrations of oxygen, there can be little doubt that the observedchanges are due to exertion on the hook and not to conditions of holdins fish on

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t04 JOURNAL FISHERIES RESEARCH BOARD OF CANADA, VOL. 16, NO. 1, 1959

board the vessel. Further, the degree of lactic acid response is shown to be signi-

ficantly correlated with the occurrence of death. The possibility of psychosis lead-

ing to death from close confinement exists; however, death also occurred in Black's(1957c) tame (hatchery raised) sockeye following forced exercise.

An experiment, similar in several respects to the present one, is reported byMilne and Ball (1956). These authors held troll-caught coho salmon (O. kisutch)aboard a research vessel from 1 to 6 hours and then transferred them to a live pond.

Of 55 individuals considered suitable for tagging, 11 died while in the live tankaboard the vessel. This fraction, converted to percent mortality, is 20%. The0.95 binomial confidence interval is l0% to 3OVo. This confidence inter-val may becompared with that for chinook held 4 hours (Table III), 30.2% to 61.7%. ThusMilne and Ball's data yield an estimate of mortality that is clearly lower than thatof the present experiment. This discrepancy may be due to the species used or todifferences in experimental conditions as well as the variable holding time of thecoho.

The present study has not demonstrated that the death of the chinook salmonwas due exclusively to the severity of forced exertion. Other factors may havecontributed to, or possibly have been primary causes of, death, e.g. unrecognizedinternal injury, psychosis from close confinement, handling, abrasion of the mucouscoat. Nevertheless, the authors are of the opinion that the principal factorcausing death was severe muscular exercise. The average degree of muscular workdone by chinook while on troll gear is much more than normally occurs while thefish is free in its environment, hence no biological adaptation for work of thisintensity is present. Fatigue to this degree is often fatal. Thus fatigue is animportant consideration in planning a tagging experiment and must be consideredin any evaluation of benefits expected to accrue from a size regulation.

ACKNOWLEDGMENTS

It is a pleasure to acknowledge Captain Ingvold Ask for the part he playedin the present study. In addition to the facilities provided free of charge aboardhis vessel Scenic, Captain Ask took a personal interest in the progress of the fieldrvork and assisted in numerous ways. Dr P. A. Larkin, Director of the Institute of,Fir:heries, Dr S. W. Nash, Department of Mathernatics, University of British Colum-bia and Dr W. E. Ricker of the Fisheries Research Board of Canada, contributedto the statistical analysis. Dr C. C. Lindsey, Institute of Fisheries, University ofBritish Columbia, critically read the manuscript. To the Alaska Department ofFish and Game, through Director C. L. Anderson, to the National Research Councilof Canada and to the British Columbia Electric Company the authors are indebtedfor funds, laboratory supplies and facilities made available.

R.EFER.ENCES

Be.rss, DaNrsr W., aNo Russnrr VtNsoNnetnn. 1957. Use of louvers for guiding fish-Trans. Am. Fish. Soc. for 1956, 86: 38-57.

Brecr, Eoce.n C. I957a. Alterations in the blood level of lactic acid in certain salmonoidfishes following muscular activity. I. Kamloops trout, Salmo gairdneri. l. Fish. Res. Bd..Canada, l4(2) : 117-134.

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PARKER AND BLACK: FATIGUE IN TROLL-CAUGHT SALMON

1957b. Alterations in the blood level of lactic acid in certain salmonoid fish follow-ing muscular activity. II. Lake trotfi, Salvelinus namaycush. Ibid., l4(4): 645-649.

1957c. Alterations in the blood level of lactic acid in certain salmonoid fishes follow-ing muscular activity. III. Sockeye salmon, Oncorhynchus nerka. Ibid.,14(6):807-814.

1958. Hyperactivity as a lethal factor in fishes. Ibid., l5(4): 573-586.Brecr, Eocen C. eNo Iseoons B.Lnnerr. 1,957. fncrease in levels of lactic acid in the blood

of cutthroat and steelhead trout following handling and live transportation. CanadianFish Cuh., No. 20, pp. 13-24.

voN BuoosNsnocr, W. 1938. Beobachtungen ueber das Sterbengefangener Seeflsche undueber den Milchsaueregehalt des Fischblutes. Rapp. et Proc.-Verb., Cons. Inter. Explor.Mer , l0 l ( IY /2) :3 -7 . .

DnurNc, W. E. 1943. Statistical adjustment of data. John Wiley and Son. 261 pp.Hewr, Purrrp B., BERNAno L. Osr,n e.No Wrrrra.u H. SuMNrEnsoN. 1949. Practical

Physiological Chemistry, 1.2rh F,d. The Blakiston Company, Philadelphia, 1323 pp.HuNrslraN, A. G. 1938. Overexertion as a cause of death of captured flsh. Science,

87(2269'): 577-578.MrrNe, D. J., eNo E. A. R. Bur. 1956 The mortality of small salmon when caught by

trolling and tagged or released untagged. Fish. Res. Bd. Canada, Pacific Progress Rept.,No. 106, pp. 10-13.

Penxrn, Rosenr R., eNo WerrBn KrmNrss. 1956. King salmon and the ocean troll flsheryof Southeastern Alaska. Alaska Dept. Fish., Res. Rept., No. 1, 64 pp,

Paurrr, Genlro J., eNo Arren C. Dpl-ecy. 1958. Changes in the swimming ability ofColumbia River sockeye salmon during upstream migration. Univ. Ilashington College ofFisheries, Tech. Rept., No. 46, 67 pp.

SecoNo.tr, ManceL, AND DIEGo DrAz. 1942. R6cherches sur la lactacid6mie chez le poissond'eau douce. Compt. Rend. Acad. Sci., Paris, 215: 7 l-73.

Sunrecon, G. W. 1956. Statistical Methods, 4th Ed., Iowa State College Press, 485 pp.

APPENDIX. Summary of raw data pertinent to fatigue-survival study, chinook salmon.

Apparent condition

105

TimeSample on Time innumbef gear live box

Forkleneth

when whenlanded sampled

Estimated Lacticweight acid

Seriousinjuriesnotec

min

2 53 37 58 1 0

10 101 1 1 012 101 3 1 01 4 815 1516 151 7 91 8 71 9 720 152 1 52 2 723 1024 152 5 82 6 627 1528 1529 223 1 8

hours &minutes0-43-01-3 01-300-51-01-01-02400-00-0o-450-45z-200-401-30L-25/ a <

3-01-102-00-300-209-01 _)O

pounds

10.21..94 . 15 .9

10.95 .9o - l

3 . 316.412.717.24 .46 .3

14.88 . 16.78 .65.97 .26 . 1

12.14 .83 . 0

80.512.7

mEVo

3 8 . 887.3

r 1 7 .83.23 8 . 8

202.108.122.194.88 .4

1 0 1 .93.7

145.125.149.1 98 .160.160.216.1 8 5 .190.240.

9 .67 .2

174.

livelylivelylivelylivelyweaklivelylivelytiredlivelylivelylivelylivelylivelylivelylivelylivelylivelylivelylivelylivelyliveIylivelylivelylivelyweak

inches

28.0weak 16.5weak 2l.oweak 23.5

28.5dead 23.5dead 24.5weak 19.5weak 32.5

30.03 3 . 0

weak 21.5weak 24.0weak 31 .5weak 26.0weak 24.0weak 26.5lively 23.5dead 25.0weak 24.5dead 29.5weak 22.0weak 19.0lively 25.0

veryweak 30.0

nonenonenonenonebled badlynonenonenonenonenonenonenonenonenonehook near eyehook near eyenonenonenonenonenoneblednonenonenone

J. F

ish.

Res

. Bd.

Can

. Dow

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from

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106 JOURNAL FISHERIES RESEARCH BOARD OF CANADA. VOL. 16. NO. 1. 1959

APPENDIX----c o nt i n ue d

Apparent conditionSeriousinjuriesnoted

Lacticacid

Fork Estimatedlength weight

when whenlanded sampled

TimeSample on Time innumber gear live box

323334353 637383940A 1

^ 1

4 J

44454 0

4748505 1525354555 6575 859606263646566676869701 1

72t 3

74

mtn.

67

1 0z015101 51 07

1 0l f

9l 51 08

20l4301 51 1201 51 52015l )

10l 578

l 015l )

151 51 010104

10l 3

hours &minutes

1 - r 5

1-250-553452-551-02-0o-25l-453-452-r00-01-102-0I -3 )0-04-201-101-55t-402-102-505-25

l0-253-253-52-452-356-15

5-505-06-02-25l - J )

5-354-158-305-s02-355-30

livelylivelylivelylivelylivelylivelylivelyweakweaklivelyweaklivelylivelylivelylivelylivelylivelyweakweaklivelylivelylivelylivelylivelylivelyweaklivelyweaklivelylivelyweakweaklivelylivelylivelyweakweakweakweakweakweak

mcqo

160.1,72.rz t .1 86 .193.r37 .216.83.2

ts7.t82.1 68.63.7

1.52.177.204.

56.7136.t63.153 .201,.216 .212.1 J + .

89.7209.149.t34.200.26.0

r95.t92.172.I 13 .226.220.177.1 5 1 .29.086.3

r74.66.6

inches pounds

weak 26.0 8.1weak 30.5 13.4

veryweak 32.5 16.4dead 22.0 4.8

veryweak 25.5 7.7veryweak 24.5 6.7

dead 22.5 5.1veryweak 23.O 5.5veryweak 21.0 4.1

dead 24.0 6.3dead 25.0 7 .2

23.5 5 .9dead 25.0 5.9dead 25.0 7.2dead 28.5 10.9

32.0 15 .6dead 27 .0 9.1dead 29.0 11.4dead 23.0 5.5dead 23.0 5.5dead 25.0 7.2dead 20.5 3.8lively 21.0 4.4l ively 23.0 5.5dead 23.5 5.9weak 33.5 18.0l ively 15.0 1.4dead 23.5 5.9lively 26.5 8.6dead 24.5 6.7weak 25.O '7.2

veryweak 22.5 5.1lively 26.0 8.1dead 23.0 5.5weak 22.0 4.8weak 31 .0 l4 . lweak .. 29.0 I l .4Iively 28.5 10.9l ively 26.0 8.1dead 30.0 12.7l ively 25.0 8.1

nonenonenonenonenonenonenonenonenonenonenonegill damagednonenonenonenonenonenonenonehook near eyenonenonenonegill damagenonenonenonenonenonenonenonenonenonenonegill damagenonenonehook near eyenonegill damagenone

J. F

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Can

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