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HomeMy WebLinkAboutAPA1832bTerritory Alaska Project F-1-R-5 Date December 31, 1~~ Volume ___ 5 __ No. __ 2 ____ __ QUARTERLY PROGRESS REPORT Surveys and Investigations as required by Federal Aid in Fish Restoration Fish and Wildlife Service and Alaska Game Commission 1~ Title: Game Fish Investigations of Alaska 2. Personnel: Leader Leslie E. vfnitesel Submitted~ Lea.der" F'ede;-al .:Ud Assistant Leaders: Robert T. Baade Roger v·i. Allin George )·l. 1;-/arner Approved: ALASKA GA.NE COlt.MISSION Date: January 17; 1.956 INDEX " i .1=10 ExperiinEnta1 'Pond· Fertilization. 11~·13 Survey of Barren illaters -Farev-le-11 Lake. • ll}--15 SUH11ARY: Federai Aid in Fish Restoration -Alaska December 31, 1955 Quarterly Progress Report -Project F-1-R-5 S£erming ~abits ~f Grayling The upstream migration occurred two weeks earlier in 1955 than it did in 1954, and is related to the open (ice free) water occurrance ~t the mouth of the inlet stream. The peak of migration in 1955 occurred on June 16 rdth the· total migration extending from l1a.y 19 to June 19 •. Spawning first occurred on June 18 and continued for five days. The spawning act was observed and the subsequent egg dispo- s~tion removed from the gravel contained over 200 eggs. Dovmstream migration after spawning began on June 20, but some fish remained in the stream longer than t.-m weeks folJowing this date when the work \'Tas discontinued. Artificially spawned and fertilized eggs were well eyed in fourteen days and hatched in eighteen days with water temperatures _ fluctuating between 430 F and 490 F. Ninety-eight, or 31.2% of the Grayling tagged in 1954 were recovered in the stream where they were tagged. Two lakes were selected in the Juneau area in the same drain- age system; one of five acres and the other of three acres. Both lakes are shallow· with the deepest having a :maY..infum depth of twenty-six. feet. Oxygen measured in :V.~arch vias over 7 ppm, and pH of 6 .. 5. Survey·o~ Barren Waters Farewell Lake is located in the McGrath area of Alaska. The lake is oligotropic and has an area of 630 acres and a maxim~ depth of 162 feet. No fish were taken in a 40 hour set of an experimental gill net. · Stockine of lake trout would appear most suitable for this lake. i r I ( -- Work Plan E, Job No. 1 Introduction Spawning Habits of Grayling in In:terior Alaska. By George W. 1-!arner Studies of the spawning habits of grayling by the Dingell-Johnson branch of the Fish and Wildlife Service were begun at Fielding Lake in the spring of 1954 and continued to the summer of 1955. The objective of this work has been to obtain a better understanding of the physical environment of spa~ming grayling and collect information on the actual spawning. The first year of this study w~s conducted by Mr. Frank Wojcik, and the second year, by the author. ~~~--------~----~-~----------~---~~-----~---¥--....---------~-+ -----• ---\ Fielding Lake is located just west of the Richardson High~ray approx- imately sixty miles south of Big Delta. It is a mountain lake at an ________ elevation of just under 3~000 feet with a surface area of approximately ~~---:i400 acres-:-~It~fs -fecCby severa1--mounta1n-streams which flow consider- able water during the spring snow m~lt, but carry little water in the summer. Fielding Lake itself is normally frozen over from the end of October to the first of June. The species of fish known to inhabit this body of w~ter include grayling, whitefish, lake trout, burbot, and -·sctilpins., ·Although graylirig are knovm to ascend at least two of the Fielding Lake tributaries to spawn, this study was confined to the second tribu- tary above the outlet on the south-east side of the lake due to its accessibility. Figure 1 is a chart showing Fielding Lake and the location of this work. Procedure In the spring, 1954 and 1955, an observation station vras .set up at the iplet of Fielding Lake to gather information on the grayling -spawning. Both years, a weir was operated in the inlet to obtain data on migration a.nd composition of run., In 1954, the weir was constructed May 24 and operated until June 12. In 1955, the ~reir was constructed Y~y 20 and ~ras in operation until July 5. Because of the violent nature of this stream during break-up, the weirs operated in 1954 and 1955 were functional only intermittently. In 1955, considerable difficulty was encom1tered until June 16, after which, the ~~ter flucuations and ice flow vere not severe enough to prohibit continuous weir operation., Afternoon temperatures as well as a daily maximum and minimum were taken of the .inlet from Jt!.ay 27 through the spa~ing period in 1955., Also, pH of the stream "'as recorded every three days., L T .. Figo lo ~~p of Fielding Lake ar · (A-l~o) Quadrangle F:Ap. ,. 2 High"'llY 1 lldle Scale 1:6336o Hayes In 1954, grayling were captured, tagged, and released to tr~ce migrationo In thi.s work a "Thite, oval shaped, flutte: tags measuring 9/16 inch by 1/4 inch were attached with cadmium '~>Tire through the flesh just posterior to the dorsal fino In 1955, ovaries were collected from eleven female grayling and :-used to calculate fecundityo In this work, the ovaries were col1ected, preserved in formalin? and later dried for countingo The actual cal- culations were made by weighing severa1 samples of 100 eggs from each fish and then weighing the complete ovaries of each fisho From this, the tota1 number of eggs produced by individual fish was ca1cu1atedo In this work, all weights were made with a micro-torsion bala.nc;eo Spawning Streamo The inlet studied is approximately 1-2/3 miles long and drains another sma11 Jake known to contain lake trout and graylingo This stream falls about 300 feet in its le.ngthj with most of the drop in the lower 3/4 mileo Through this lower section, the stream bed is composed of rock and gravelo On June 30, 1955, this stream was flowing a volume of approximately 20o3 cubic feet per secondo B,y this date, much of the ice and snow had melted and the stream flow was just a fraction of what it had be~n during the previous weeks of break-upo !Jpstream Migrati<;>t1o The spa·wning migration of grayling from Fielding Lake into its inlets begins in the spring shortly after open water appears at the stream mouthso In 1955, a pool of water was ice free May 19 at the mouth of the inlet studiedo Grayling ·Here first observed at the mouth of the inlet on June 5 vrhen five \-Jere taken in a gill net set in the pool of open water o The follNiing day the first .fish \<Tere observed entering the streamo Grayling continued to migrate into the stream until June 19 with the peak of migration occurring about June 16o In 1954, an ear1ier opening of the inlet brought on earlier spawning migration of graylingo This year the migration began about ¥~y 15 and continued until June 6o Thus, in 1954 grayling entered the stre·am at least hm weeks earlier than i,n 1955 o The afternoon water temperature and the daily maximum had begun to rise by the time grayling entered,the stream in 1955o On June 5 the afternoon water temperature was 33° Fo and June 6 it was t1.Jo degrees highero Also, the pH of the vrater had increased from 6o5 to 6o8 ppm by the time grayling entered the streamo In 1955, most of the grayling migration occurred at night bet\oleen the hours of 8~00 porno and 4:00 aomo This '~>~S especially true before the peak of the runo ~l?m-mingo In 1955, spawning was first obser~,;ed June 18, which was fifteen days later than the first observed spa<ming in 1954o Both years it continued for about five dayso 3 In both 1954 and 1955, spawning occurred while much of the stream was covered with ice and snow. In 1955, approximately 200 yards of the stream just above its mouth was open and above this, the open water was large holes in rotting ice and melting sno"'· In the spawning period, the daily flucuations in water level were quite large. During daylight hours, the air temperature was consider- ably above freezing and much snow would melt causing very high water. The night temperatures dropped to below freezing and the water level would fall to a fraction of the daily high. Actual spawning was observed in several spots in the stream both in 1954 and 1955. The following4s a description of an instance observed June 19, 1955, bet'\-reen 1:20 p.m. ahd 1:55 p.m. This is believed to be typical of observations made. ________ TJle _spawning site chosen \-18.S .a pool of open water a little over ftfty feet long. At either end of the pool the stream was covered by ice and six to eight feet of snow. Almost ever~Jhere the banks of the stream were covered by overhanging snow banks so the actual width of the stream was unkno~~. The opening through the snow was fifteen to twenty feet wide. The water depth varied up to two feet in this open section with the gravel bars approximately 6 inches deep being chosen as preferred spa-vming sit'es. The gravel in spawning areas was predominant- ly quite fine, composed of rocks the size of a pea and larger. The surface current velocity was checked at the time of spawning and found to be 3.9 feet per second. The water temperature was 42° F. Aggressive males establi-shed 11 territorial rights" and each would defend his area.against intruding males. Females spent most of their time in quiet witter or under the snovT banks., Spawning occurred vrhen a female would leave a resting spot and enter an area occupied by an aggressive male. Then the two fish 1<10uld press against each other side by side 'dth their heads upstream and vibrate quite violently. This period of vibration which is the period of egg deposition would normally last from five to ten seconds. During this time, frequently an 11 outside" male would rush into the area and press against either the spawning male or female, presumably also spawning. After each period of egg deposition, the female would return to her resting spot and the "outside" male would depart leaving the aggressive male to his· -own terri tory. This activity was observed three times in thirty-five minutes involving the same female and the same aggressive male. After this had been observed three times in the same spot, this gravel was dug up and folmd to contain over 200 grayling eggs. There was no indication of the spawning fish digging redds in the gravel and there was no attempt made to cover the spa~med eggs with gravel. The eggs \l8re not found to adhere to rocks in the gravel. They seemed to be slightly heavier than the water and would settle among the rocks. 4 f \ On the afternoon of June 1S 1 1955, which vres the first day spawning was observed, a i:rire basket made of fine screen and with an opening tviO feet by two feet square was placed in various spots near the mouth of the stream to detect if grayling eggs were being washed dovmstream by the current. In this operation, spots were selected where the water was less than one foot deep. In no instance was this net fished in the immediate · vicinity of spawning ftsh. This basket was fished four times for periods of two minutes and the number of grayling eggs captured each time record- ed. The maximum catch for two minutes was fourteen eggs and the minimum catch was four eggs. Thus, it appeared that many eggs were being washed do\m by the current. During this period there were data collected which would point to a certain amount of grayling spawning in the lake at the mouth of this inlet. ·On June lS~ 1955, a 60 foot beach seine haul in the lake at the mouth of the inlet yielded many grayling some of which were spawned out and some still spawning. Also 1 in this seine haul were many whitefisho A stomach analysis of the whitefish disclosed the presence of grayling eggs. At no time were whitefish taken at the weir or obserqed in the stream. A gill net was placed along the shore of the lake in a spring fed area, shown by "X 11 in Fig. 1, to ascertain if spavming grayling vrere pr€sent in this area. This net was fished before and during the time spavming occurred in the inlet. Only immature grayling and whitefish were taken in this net. Do~tream Migra~ion. The downstream migration was first observed in 1955 on June 20, vihich was tvro weeks later than in 1954. In 1955, observations were continued for two weeks after the downstream migration began. During this period many fish returned to the lake but at the - end of the period, many remained in the stream. A size and age compo- sition vras obtained from a sample of 173 of the dovmstream migrants and believed to be representative of the run. The per cent composition by size for 1954 and 1955 is given in Figures 2 and 3. The per cent compo- sition by age is given for both years in Figure 4,. The age given in this graph is the age in number of i'linters shown on the scale. · It appears that the size composition of the run was approximately the same for both years. The age composition of the 1955 fish appears more weighted in the six year class than the 1954 fish. This is be- lieved to be caused by the scales being examined by one individual in 1954 and another in 1955. It is not believed to indicate a change in age composition. Fecundit~. Grayling ovaries were collected from eleven spawning females to ascertain the number of eggs produced by fish of various lengths. The fecundity is expressed as a fQ~ction of fork length in Ftgure.5. Using the formula N:. FLX in which N is the number of eggs 5 15 .p ~ ~ 10 ~ Q) P-t 5 N = 185 \ \ I I ' ' r25·· 30 .35 40 45 Fork Length in Centimeters \ *All fish withfork length 27 cmo or smaller grouped in this classo · Figo 2o. Size composition of 1954 Fielding Lake spawning r'uno 15 N = 173 25 .30 35 40 45 Fork Length in Centimeters *All fish with fork length 27 cmo or smaller grouped in this classo :F'igo 3o Size con::position of 1955 Fielding Lake spa-vming r'tlno 6 . . 40 10 ----1954 N = 323 --1955 N ::: 134 I r--- 1 I I I , ' I I I I I , . --- ~---- II I I I , , _ ... rv v Age in Winters -...... __ ~ IX Figo 4o Age composition of Fielding Ls.ke grayling spawning run, 1954 and 1955o 9000 rc:l ~8000 :;:1 rc:l 0 S.. P-. 7000- tf.l hrJ hrJ Pil e.-;6000 0 S.. (!) ~5000 z rl $4000 0 ~ 3000, 32 • • 34 '" • • Fork Length in Centimeters Figo 5e Egg production of Fielding L:'lke grayHng 9 1955o 7 produced, F is a constant, and L is the fork length to the power x, a line was fitted by the method of least squareso Solving the equation for F and x~ it was found that the Number of Eggs produced = Oo0030 X Length 4o 02~4 0 · Egg Develonmerl!!o In 1954, approximately 6000 grayling eggs were collected and hatched in the water of the inlet being studiedo These were kept at temperatures flucuating from 43° Fo to 49° Fo These eggs were eyed in fourteen days and hatched in eighteen dayso Taggingo In 1954, 344 grayling ware captured and tagged at the inlet studiedo Thirty of these fish "\-rere recaptured by anglers in 1954 leaving 314 believed to be at largeo Sixty-eight of these were taken and released in the upstream migration in 1955 and an additional thirty taken in the downstream migrationo Thus, 98 fish or 3lo2% of the tagged fish were known to have returned to the inlet to spawno Age classes four through eight were the only ones in which enough fish were tagged to d1~w any conclusionso The per cent return of each age class tagged is sho'rm in Figure 6o 50 N ~ 98 45 40 ..., ~ <I> 0 35 J..i Q) p... 30 25 . ..,. ~[Z: !::~-" I I ! I ~I rv v VI VII VIII Age in \linters '\omen Tagged Figo 6o Per cent tag raturn of each age class of Fielding Lake gr~yling tagged during the 1954 spaw~ing run--recaptured during the 1955 spa:wning runo 8 ,/ . . ,.,, . . It is unfortunate the water conditions prevented the weir from taking every fish in the 1955 spai-rning runo This would have given a much more complete picture of returning tagged fisho Ho-wever 7 a good sample (368 fish) was taken of which 68 fish or 18o5% were bearing tags attached in 1954o In the do1-mstream migratiori 9 273 fish were taken including thirty fish tagged in 1954 and not captured on the upstream migrationo F'rom this it is calculated that 90? grayling migrated into the streamo If 18o5% of these were tagged lll 1954~ this would be a return of 168 fish or 53o5% of the 314 tagged fish at large returning to the spawning stream one year latero Conclusions As soon as the·water temperatures of the inlets of Fielding Lake begin to rise in the spring 9 the grayling sta.rt their spavming migrationo This migration is to a large extent while tnuch of the streams is covered by ice and snowo Spavming occurs vlhen the maximum daily water temperature reac]:les approximately 40° F o D-uring thls period ·the pH of the stream is still slightly acid but becoming more neutralo · Spawning appears to take place on shallo·w gravel cars at a high stage of watero It was observed in 1955 that many of these bars v.rere dry when the water level dropped a few days after spawningo Doubtless~ a certain amount of egg mortality resultedo Although grayling eggs have a slightly higher specific g::t'avity than the 1-ra ter, many \-Jere being carried do-vmstream by the current during the 1955 spavnlingo-This probably resulted in some egg mortal:i.tyo It appeared in 1955 that many g::tcayling were spa~;ming in the lake at the mouth of the inleto This may be normal; it may have been caused by a late break-up in the tributary stream; or it might. have been caused by the i-Teir blocking their upstream mig:rationo No grayling -vmre found to be spaw~ing in the spring-fed area of the lake shoreo A downstream migration into the lake begins just as soon as the fish have spavmedo Not all f'ish migrate doi-.rnstream iiTh-nediately after spa\-mingo FecUt!di ty appears to have a direct relationship to length of the fisho The number of fish examined in th~s study was perhaps too few to give significance to the line·fitted to the pointso There seems to be a very definate tendency for grayling to return to the same spaw~ing stream year after yearo From the tag returns, it is calculated that half of the fish tagged in 1954. rt3turned in 1955o 9 It is very interesting that the per cent of lmo"m tag return for age classes four through eight varied only from 26o7% to 40oO%o It is also noted that per cent recovery when plotted by year class suggests a normal curveo Thus it appears mortality (tagging and natural) follows a definite patter~ but is not significantly different among age classes studiedo 10 / •J Work Plan (e), Job Number 1 Exoer'...tiO.entc=t~ --Pond Fertilization ~-R;berCT'Ta"ad~. Two ponds were selected for the experimental pond fertilization experiment. These ponds lie in the moraine area before the Mendenhall Glacier near Juneau. They are relatively small and easily accessable from the road system. The water ex- change is not great in either l~ce. The ponds were given names, for clarity, of Glacier and J:.1oraine lakes. Glacier lake is approximately five acres and has a maximum depth of twenty-six feet. The water is clear and has 7.1 ppm of oxygen at the bottom in late March. There are some shallow >-reedy areas along the shore line area. Horaine lal.<e is fed by Glacier l~e and is approxi- mately three acres with a maximum depth of fourteen feet and has 7. 6 ppm of oxygen at a depth of tv.rel ve feet in lake March. The vmters of both lakes have a pH of 6. 5, using a L~~otte Color Comparator. Populations of stickleback and a fe-vr juvenile coho salmon are present in the lakes. Both lakes have been planted -vrith a number of rainbo\\' trout fry. Tem!Jora.ry screen c. of fine mPshArl hr~ rd~Vare cloth vmre placed in the outlets of both lakes in July, but -vrere found un~ satisfactor.r as leaves and stickleback made them i.noperati ve. These screens were replaced in October by experimental current-· driven rotary screens constructed of plyvrood. -11 - . ,, 1 j it / .screen 1 1 i } ! ) /It? ,l[o:-k Plan (b), Joo Nmnbcr l t:levation Area Depth Bottom Aauatic Veget~tion I:1:!.ets Outlet Fish 14 Survey of BarrE;_!!. Waters Suitable fo~_Stocking _!i;r_: F'-2_ger :I, Allin 1000 feet msl. j630 acres 162 feet Clear The shore line is corn-· posed of rock a:td boulder which is broken into fine rubble in wind swept shoal areas. The lake lies in a rolling hill .watershed of tundra~ willovT brush and sparce spruce character; draining approximateLy 1 1 ~000 acre,3. Sparce and COL.ifJC;sed of pond vl"')eds and stonewort. ,( ~ ~.tNc/A . u_. • t:V< . If'-7"t,c(t( 'F~,_,( None None Reported be.rr·enc taken in 40 ho'U.r No fish set of experimental mes~ gillnet. An oligotropic lake, deep and >-Iith sufficient area, Best defined as lake trout env:i ronment vl:L L~1 ~·os;:>i ble introdu~tion of fo~~ge fish. · ..