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BRISTOL BAY DATA REPORT NO. 86-12
Techniques of Aerial Assessment and Methods of Aerial
Identification in the Togiak Herring Fishery
by
·Michael L. Nelson Fishery Biologist
Alaska Department of Fish and Game Division of Commercial Fisheries
Dillingham, Alaska
t1arch, 1985
ARL·~·; Alaska Resources Library , .... i ,lfnrmation Service~
Library Buildin~. Suite J 11 3211 ProYit.kncc Drive
t\nchoragc. AK 99508-+614
sH 1-1-2 . 1\l-{ Dlt
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BACKGROUND
TOGIAK RIVER SPORT FISHERY'}''.
By: R. Eric Minard
Fisheries Biologist II
The Tqgiak River is located within the confines of the Togiak National
Wildlife Refuge (TNWR) on the western side of Bristol Bay. It is
generally a clearwater river that supports the second largest runs of
chinook and coho salmon in Bristol Bay. Sockeye, chum and pink salmon
are also found in abundance as are Dolly Varden and rainbow trout.
Guided and non-guided effort is increasing as the river gains populari
ty. TIIWR sta:ff have placed a cap on guided use levels, however, non
guided use remains unregulated. The river is fished by primarily fly-in
or float-nip anglers. Angler effort has averaged 1, 623 · angler-days
since 1~79. Since 1984, however, angling effort has exceeded
3,506 angler-days.
The Togiak River is particularly popular for its chinook and coho salmon
fisheries. Togiak coho are the largest coho returning to Bristol Bay
making them a prized fish.
Present levels of harvest of all sport species in the Togiak are consid
ered insignificant in the overall exploitation. Directed CO!DDiercial
salmon fisheries harvest the greatest share followed by subsistence and
personal use fishermen.
MANAGEMENT CONCERNS
With increasing angling effort, trespass conflicts between native
private landholders and sportsfishermen have begun to create tension
between user groups. Poorly marked land boundaries and insufficient
3 3755 001 12089 8
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research by the angling public has contributed to the problem. As a
result of user group conflicts, regulations have been proposed to
severely restri-ct sport fishing on the Togiak River. There is no
biological justification for restriction which therefore makes this a
purely allocative issue.
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Table 1. Togiak River sport harvest of chinook, coho, rainbow trout and Dolly Varden, 1979-1984.
Effort Rainbow Dolly Year Angler Days Chinook Coho Trout Varden
1979 ' 1,666 78 300 82 236
1980 1,513 34 258 215 560
1981 932 119 130 345
1982 1,160 231 524 168 671
1983 972 535 294 336 1,007
1984 3,497 87 1,154 75 848
Sources: 1979-1984 Statewide harvest summaries
INTRODUCTION
=ORAL PRESENTATION=
(Kodiak Community College) Kodiak, Alaska
TECHNIQUES OF AERIAL ASSESSI·1ENT AND METHODS OF SPECIE IDENTIFICATION
-TOGIAK HERRING FISHERY-
By: M. Nelson Date: 3/20/85
My presentation today will address some of the aerial survey assessment
techniques and ·specie i denti fi cation methods current1 y being used in the Togiak
herring fishery.
My involvement with the Togiak fishery has been primarily with estimating
the total herring resource (or biomass) so that the Board of Fisheries manage
ment directive of harvesting 10 to 20% of the observed biomass can be met.
Ny aerial survey credentials include 23 years of extensive salmon aerial
work in Bristol Bay, and 18 years aerial work with herring in the Togiak area,
however, intensive aerial surveillance of the Togiak herring resource did not
begin until 1977, when· the fishery began to expand rapidly.
AERIAL SURVEY. PROGRA~1
The present aerial survey program at Togiak has evolved from the late 1960's,
when 4 or 5 surveys were flown each season to primarily keep track of the
commercial effort and document relative abundance of the herring stock. The
present-day program can include as many as 30 to 40 flights with fixed-wing '· aircraft and additional aerial coverage w/helicopter aircraft.
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.-Specific objectives of herring aerial surveys are to:
1. determine seasonal distribution and relative abundance of herring
schools and spawn within each fishing section;
2. estimate the biomass of schooled herring by converting surface area
estimates to short ton equivalents;
·3. determine spedes composition of fish schools sighted by working with
test fishing crews;
4. compare the accuracy and repeatability of aerial surveys;
5. document movement of herring_ schools in relation to time of day and
stage of tides; '-~
6. estimate commercial fishing effort (and effort distribution) for the sac "
roe, roe on kelp fisheries; this is mostly accomplished with the
helicopter; and
7. to develop new techniques for accurate biomass assessment.
Some of the problems we face when using aerial surveys to .assess
herring abundance include:
1. species composition of schools observed during surveys is sometimes
questioned and often not confirmed through test fishing;
2. survey coverage is often limited by .adverse weather, poor water clarity
and lack of funding;
3. movement patterns of herring schools prior to, during and after spawning
are not entirely known; ·and therefore, schools could be enumerated more·
than once and., in fact, probably are;
4. spawning herring (which is observed as cloudy areas of milt) are recorded'
as "miles of spawn", but this information cannot presently be used in
calculating relative abundance or biomass;
5. behavior of herring in relation to various physical characteristics, such
as water depth, time of day, etc.) and physiological (such as sexual
maturity, spawning condition, etc.) are not known and these factors could
and probably do, affect survey and biomass conversion results; and
6. last, and the most important to my way of thinking, few determinations
have been made relating school surface area to biomass, (only 19 estimates
have been made in Bristol Bay and only six of these were based on actual
landing of captured herring).
THE PRESENT DAY SURVEY PROGRAM
I'll now discuss the survey program as it currently stands.
Equipment
Most biomass estimates are made with fixed-wing aircraft, rather than
helicopter because of the large area that needs to be surveyed and the limited
range of the chopper. The total survey index transect includes over 250 miles
of shoreline from Cape Constantine to Cape Newenham and occasionally I also
provide aerial support as far west and north as Goodnews Bay. I prefer to
use a Cessna 185 w/STO~ capabilities and bubble window. We always survey
w/a pilot and 1 or 2 Department observers rather than a single pilot/observer.
The pilot has general control of the aircraft and helps keep altitude, and
watches for other aircraft. I make surface area estimates and count schools
of herring, while steering the aircraft w/my left hand. I've tried head-set
communications units between pilot and other observers, but the chatter
interrupts my concentration and as such I prefer hand signals to the pilot.
Steering the aircraft allows me to deviate from the flight path without
having to instruct the pilot to do so. Using this method I also often roll
the aircraft on its left wing to take a quick look at herring distribution
out the left window (the only negative comments I've received using this
method has come, from the second Department observer in the back seat - come'
to think of it he doesn't like the way I turn, either).
I prefer to use reduced topographic survey maps and record directly
6nto the.map all collected data. I've tried small pocket tape machines,
"but the aircraft engine noise makes retrieving the data difficult; and I'm
always fearful of losing the survey data if the machine malfunctions.
Other equipment aids include. a stopwatch for timing 1 ength of 1 arge
schools, a tally whacker for enumerating schools, several sighting tubes
with calibrated grids and known focal length to help estimate surface area
size, and a portable VHF radio to talk''with our field camps and to relay .-.- ,.· .r·
biomass info. to Jeff on Summit Island.
I've occasionally used camera gear (both 8 mm movie and 35 mm) to
document herring school size(s), and all flights include the following . . ' .· -~ !~': \
safety gear: (1) emergency locator beacon w/2-way voice trimsmission
capability; and (3) life jackets.
Some of the new equipment we're presently looking at is a "clinometer"' ---- -·- - -
to help define.the angle we're viewirig"fish at, as fish schools off the
flight p~th a~e larger than they appear, and'it is often impossible to over:. ' fly all schools, as well as up-graded calibrated sighting tubes.
-' '._,
Survey Area
' ·_t_.::_ ·.'
. - :· ('' . ';.•' ~: . The entire Togiak area is divided into 13 survey index area w/appropriate
index maps. Generally surveys commence in mid-April, but commencement of . . ..
surveys is closely tied to both Bering Sea ice coverage and water temperatu·r~s. ' ' ' ~ j ' ' . • ' • -.! . . -.
(I might add that funding this season was tightened considerably, and we will ,.•.
·-'.
not conduct as extensive a "early-season" survey schedule as we have in the
but rather will rely, to a larger extent, upon commercial spotters to keep
abreast of ice and early herring arrival).
A general early-season survey will cover that area from index area 2
mid-way on the Nushagak Peninsula to "Asig. Spit" in Osviak Bay. This
tract is flown every 3-4 days. As the season progresses and fish begin to
show inshore (usually in Togiak or Kulukak Bay, or the Tongue Pt. area,
survey frequency is stepped up, and every 3rd flight or so will include that
·area west of the Spit to Cape Newenham and Hagemeister Island.
Herring arrival by area is not entirely predictable, but my observations
indicate one major incoming (as well as outgoing) area is on the seaward
side of Hagemeister Island moving into Togiak Bay. In other years fish will
first show offshore in the Kulukak Bay area. Water temperature(s) and certainly
ice cover especially to the west play an important role in determining when
and where fish will show.
As we get into the season, survey flights are scheduled daily or twice
daily, and the Summit Island based helicopter also is used for biomass assess-
ment work.
SURVEY METHODS
Actual survey assessment of herring school size includes:
1. recording school size and observation angle, location of the schools
on a map so that differing biomass conversions can be applied by
area and water depth;
2. schools are listed as: small - surface area less than 538 sq. ft.
(I call these skiff or Bristol Bay power boat size schools);
medium- greater than 538 sg. ft. but less than 4,840 sq. ft. (i.e.:
example, would be 50'x50', 100'x30', etc.); and
large- greater than 4,840 sq. ft. (i.e.: lOO'xlOO', 250'xl00',
etc.).
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If large schools are fairly well defined, I '11 use the stoP,wa
speed method to estimate surface area. If the school is sta~iol)ar~''-'i
I' 11 often make 2 or 3 stopwatch runs on it and average the resul:ts.
If there. are many 1 arge schools,, I' 11 over-fly the _entire ar\!.~ qn,ce;, ,_ · I _, ~ ·, ~ ,, ' '
and then select an appropriate size, 100' xl 00' ro 250 'xl 00' , as shown~
on the map and then convert all schools seen to equal these parameters) - ' ' .. - ·- '', .. _ '' ' - '-· ~
When biomass is very heavy as .it was on this May 20 flight last year ... , - _, \, .. ' '- '4
in Kulukak Bay, I'd defy, anyone: to count all schools by size category; .
3. I use the sighting tube to help estimate school size when there are . . . :...·
4.
few schools., The sighting tube helps me early in)_the season to si?e:li
my eye (so to Speak). !,.commonly practice oirD.illingham hOUl>e(s}_, 1:,;;.
___ schools, rq~~ widths and. beach are~s. I always use known proc_esso,r ,:·t
_ship length~ and .fishing vessel.,lengths to help estimate school stze.,.,J;
If large schools are laying in near-shore areas, I '11 mark on th~.map,,;
__ and use pr;ominent map points to estimate size.
I prefer to fly at 1,500 ft. altitude, 2,000 ft. is o.k. also, but·-''" : ".
higher than about 2,500-3,000 or lower than 1,000 ft. is unacceptable,;,· .C.-'.:~c;,O,'d
to me. All flights are in a flaps-up mode, un 1 ess there's rea 11 y
heavy biomass, then we'll gotoflaps and·slow aircraft down to just
above stalJ_speed~ I also use the pi.lot to generally keep.me abreast_ .· - ,. . ;• ' . ,- ·•
of fish distribution on the left.side. of the aircraft •. _
5. Although herring can be observed at all tide stages, L pre_fer, to fly
at low water and on the rising flood tide. Fish seem to be more confi
and grouped together on the flood. A mid-afternoon or early-evening
flood tide is particularly good. Early in the season as fish are
forming offshor~,before coming in, several key areas have_ produced ..... -
good results; example of these_ areas are offshore Kulukak Bay, outer. -
Nunavachak, outer Togiak and Tongue Pt. and particularly the seaward
side of Hagemeister Island. Also, fish will lay with the tide rips,
and both the Togiak and Kulukak Bay rips will help define fish
location. Once spawning has started and spawnout(s) are prevalent,
the shallow water area of these 2 areas seem to be favorite resting
areas.
6. 'If herring are widely scattered, as often is the case in Togiak and
Kulukak Bays, I'll fly a grid pattern across each bay, using landmarks
and compass heading(s) to stay on track.
7. Most flights require about 2-l/2- 3 hrs. to complete, and up to 4-1/2
to 5 hrs. if the biomass is heavy and widely scattered. All fixed-wing
survey(s) originate out of Dillingham, and this is a personal choice
of mine, as well as need to have a knowledgeable Department staff member
in Dillingham to provide information on the fishery to the waiting world.
8. Once the survey is completed the time consuming data analysis is begun.
Again, if the biomass is heavy and widely scattered, data crunching can
take 2-3 hrs. to complete. We hope to shorten this time in the future,
with the use of computers and programs written to quickly provide area
and section biomass estimates.
9. The inseason data analysis required to give Jeff the biomass estimates
he needs to-set fishing periods is derived in the following manner:
A. Schools are tallied by size category: Small Medium Large
B. Surface area by school size 'is equal to:
1. 538 ft. 2 for s~~li schools and is equal to 1 R.A.I. (relative
abundance index), or 1 index point.
2. 2,690 ft. 2 for ~ediu~ schools, which is the approximate mid
point between a small and large school, and is equal to
5 R .A. I . 's, and
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,, ': :·1 3. The total surface area of all large schools, divided by
538 ft. 2 equals the number of R.A.I.'s for all large schools.
C. All R.A.I. 's are then totaled by index area;
D. Biomass conversion(s) are available for 19 separate 'data points
and show the ·following:
1.52 short tons per R.A.I. for 16ft. of water or less,
2.58
2.83
"
"
"
"
" " " 16-26 ft. water,
" " " ~11 estimates.
E. Appropriate conversions are selected by index area, and the total
R.A.I.'s multiplied by the conversion yields the biomass estimate;
10. This transparency shows a summary of all surface area biomass convers·i
estimates. We have 19 data points, yet, as I indicated,
points are actual pumped catches (shown by circles). In general, the
data shows more biomass per surface area as the water depth·. deepen~.
There also appears to be density changes between pre and post-spawners,·
and in fact, school appearance is often a tip-off to whether fish are
spawn-outs or good fish.
11. This last transparency (T7) shows an actual aerial survey worksheet
completed inseason in 1984. The 3 columns in the center (circled in
red) of this table show how the conversions are applied by index arf:!a:
You'll note that for the Togiak index area I used 1.0 conversion, as
all fish were in extremely inshore shallow water. You'll also note ..
in the far right column my personal biomass estimates. I make these
estimates in the aircraft, either right after surveying the index area
or on the return flight to Dillingham . .If survey methods are consistent~
an experienced surveyor should see the two (2) estimates closely match
each other as the season progresses, as each previous survey results,
influence estimates on later surveys.
12. Specie identification at Togiak is generally confined to distinguishing
between herring, capelin and smelt. Smelt are not a major problem at
present, their biomass is relatively small compared to herring, and
I've learned where to expect them and they generally look lighter in
color (i.e.: less dense) than herring. However, in 1979 what I was
sure were smelt laying along west side of Tongue Pt. proved to be age
2 herring when test nets were set on them. Like all others, I've had
trouble telling herring from capelin. Fortunately, the two (2) species
do not over-lap significantly in run timing. As the herring run begins
to wind down, capelin begin to show in greater numbers. Capelin often
appear in very small, tight balls laying in close proximity to gravel
beaches where they spawn, or as steady dark bunch along gravel beach.
Often times they appear with odd-shaped "tails" and appear a blue/
black in color. We all can be fooled, though in 1984 near the end
season after most effort, fishing and processor alike, had left Togiak,
on extremely 1 arge biomass of 30,000 tons or so began to show off
Kulukak and the upper Nushagak Peninsula. Everyone got pretty excited
for awhile until P/S test sets proved them to be capelin. Correct
specie identification can only be guaranteed with test fishing on schools
sighted.
Last, I'd like to show a few slides which show some of the country
involved and both pre and post-spawning herring.
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@) Relative abundance of herring stocks in the Togiak district, Bri sto 1 Bay, 1967-77.
Total Relative Aerial Fl i qhts Number Schools Stock Sizol/
Year Number Dates Si hted Sma 11 ~1ed. Lo. · v. 1967 2 5/19-27 ndete mine
68 5 5/21-29 Very Numerous X
69 1 5/31 / ndete mine
1970 3 5/19-28 Numerous X
71 2 5/24-28 ndete mine
72 2 5/25-6/ 5 X
73 5 5/18-30 X
74 3 5!21-24 X
1975 6 5/27-6/15 152 ndete mine
76 8 5/20-6/12 734 X
77 10 5/11-6/ 3 648 X
lJ Personal observation by the same observer
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rao1e 1. Summary of herring aerial survey total run biomass estimates and observations of herring spawn, Togiak district, Bristol Bay, 1983.
Date
4/Z6 ' • 27 . 29 : 30
Census Survey11 Area 21 Ratins: Surveye~
G NUS2-0SV1 P NUS2-TON1
G/F NtlS2-HAGl ' G NUS2-HAG1
· 5/ 2 P/U NUS2-MAT1 NUS2-0SV1 NUS2-0SV1 NUS2-UNG1 NUS2-0SV1 NUS2-05Vl NUS1-0SV1
3(AM) F/U 3(PH) F/P 4(AM) P/U 4(PM) G/U S(AM) G/F S(PM) G/U
6 7 8
11
12 13 15 16
17 18 19 20
23 25 26 27
30 6/ 1
3
F/G G/E G/E P/U
. G/P P/U F/U F/P
NUS1-PYR1 NUS2-HAG1 NUS1-HAG1 NUS2-HAG1
NUS1-HAG1 NUSl-TOGl . NUS2-HAG1 NUS2-HAG1
G/F NUSl-HAGl G/E NUSl-CNl G/F NUS1-PYR1 P/U NUS2-TONl
.P/U u
G/E E
NUS2-0SV1· KUL1-TOG1 NUS2-PYR1 NUS2-PYR1
P/U NUS2-TOG1 G/P NUS2-0SV1 G/F NUS2-0SV1
Smail
12
53 17 9
17
18
2 3
Number Herring Schools Observed
Herring 3 Herrino Soawn M1 1 es
Medium Large Total a·; amass Est .J 11 Formula Staff No. Each Accum.
325 10
139 426
98 268 293 263
176 10 -Fleet Survey-
239 102 1
272 340 225 228 394 317
292 421 940 38
161 10 58
194
421 365 110
49
152 42
26
263 297 650
4"6
357 15 89
162
219 236 210 .
5
1 2
65 65
1 4 9
423 15,600 278 11,500 432 62,500 701 59,000
186
341 1
612 453 711
608 735
1,599 84
14,100 150
73,600 22,500 38,500
37,900 52,100 9],600 41,000
518,. 84,100 25 · BOO
147 37,900 373 .· 76,200
.' .-"
13,800 20-25,000 50,000 53,700
80,000
15,500
70,700 18,100 32,200
34,400 47,300 96,500 33,600:
76,300 500
34,300 89,600 .
"10 3.6 3.6 7 2.5 6.1
23 6.8 12.9 8 3.3 16.2
32 9.2 25.4 19 5.3 30.7 8 2.2 32.9
8 8 8 3
.9
2 4
2.9 1.5 1.9 3.5
5.4
1 .0 0.5
35.8 37.3 39.2 42.7
48.1 48.1 49.1 49.6
658· 83,800 88,100 . 9 601. 114,200 105,100. 19
2.0 51.6 6.1 57.7 1.7 59.4 320 -70,70Q- 7
54 400 450
1 500 2
219 39,200 110 40,800
1 4
35
+ 180
1,200
6,000 2,000
36,200 40,400
200
59.4
.59 .4 1 0.1 59.5 1 0.1 59.6 2 0.1 59.7
1
59.7 59.7
+ 59.7
l/ Survey rating: U s unacceptable; P s poor; F • fair; G • good; and E • excellent. £/ Inclusive census areas: NUS 1 and NUS2 • Nushagak Peninsula; KULl • Kulukak;
METl • Metervik; NUN1 • Nunavachak; UNGl ·• Ungalikthluk; TOG1 • Togiak; TONl • Tongue Point; MATl s Matogak; OSVl .. ~ Osviak; HAGl • Hagemeister; PYRl • Pyrite Point; and CNl • Cape Newenham.
3/ Short tons. 11 Formula: Total RAI's x conversion factors of 1 .3, 2.4, and 3.4 tons, by census area and fish density/distribution; · · ~: Personal estimates by experienced Department spotters.
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BIOMASS ESTIMATE
1. SCHOOLS ARE TALLIED BY SIZE CATEGORY: SMALL MEDIUM LARGE
2. SURFACE AREA BY SCHOOL SIZE IS EQUAL TO:
A. 538 FT. 2 FOR SMALL SCHOOLS AND IS EQUAL TO 1 R.A.I. (RELATIVE
ABUNDANCE INDEX).
B. 2,690 FT. 2 FOR MEDIUM SCHOOLS, WHICH IS THE APPROXIMATE MID
POINT BETWEEN A SMALL AND LARGE SCHOOL, AND IS EQUAL TO
5 R.A.I.'S, AND
C. THE TOTAL SURFACE AREA OF ALL LARGE SCHOOLS, DIVIDED BY
538 FT. 2 EQUALS THE NUMBER OF R.A.I.'S FOR LARGE SCHOOLS.
3. ALL R.A.I. 'S ARE THEN TOTALED BY INDEX AREA;
4. BIOMASS CONVERSION(S) ARE AVAILABLE FOR 19 SEPARATE DATA POINTS
AND SHOW THE FOLLOWING:
1.52 SHORT TONS PER R.A.I. FOR 16FT. OF WATER OR LESS,
2.5B
2.83
II
II
II
II
II
II
II
II
II 16-26 FT. WATER,
II ALL ESTIMATES.
5. APPROPRIATE CONVERSIONS ARE SELECTED BY INDEX AREA, AND THE TOTAL
R.A.I. 'S MULTIPLIED BY THE CONVERSION YI.ELDS THE BIOMASS ESTIMATE.
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l!~~D 1t!~ll [Tl!) 1m - m - ra - 1!:.!1 rr;::li:l - - - - - a E!l Cl:·)I\J.t>endix 'l'able 1. SUrface area and blanaoo converoion estimates of herring schools, by aerial survey,
in the 'lbgiak district, Bdotol Bay, 1978-83. '
Year Mont tV
O;!y
Est. of School TOns Per Size 511111 sq. m. 1/ in Feet .
Weight of-
Catch in Metric Tons
l\Ctual · or Est. lielght of Catch
Fish Condition
lncation of Puroe Seine Set
1978 5/13 18
6.7 11.0
2/ 00 X 60'
2/ 100
Estimated Estimated
2/ Nunavachak Bay 2/ Nunavachalc Bay
1979 5/ 4
1980 5/15 15 16 16
20 20
1981 5/ 3 8
10
1902 5/15
1903 4/30 30 30
5/11
18 10
2.4
1.2 ·1.6 1.1 3/ 1.2
3.0 2.6
1.1 1.7 4.0
1.9
1.1 1.0 1.5 1.8
1.7 2.2
40 dia.
60 X 40 40 X 30 ·
220 X 50 65 X 20
70 X 70 150 X 75
400x-200 80 X 30 .
150 !!'60'
200 X 150
150 X 80 350 X 143 60 X 30
200 X 200
300 :x' 50 60 X 60
5
5 4
19-3
27 54
80 7
40
100
55 91
3 127
45 14
(kt~ab Ripe
.1\Ctual Ripe Estimated . Spawn-outs
(_lii:l:iiiil"'J Spawn-outs kiiUmated Fish lost
''·'
Estimated Ripe Estimated Fish loot
l:~~=~"l ~;;;
Ripe Spawn-outs Ripe'
Estimated Green
Estinated Green Eiittm ted Greeri i EStimated' Green ·· Estimated Ripe'ftnd
Spawn-outs Estimated Spawn-outs Estimated Spawn-outs vl< ;;l.'iJ- 2.6 He~ All Esti~tes . ·. ·
6)11) 5 1.5'~ -1.4 Mean Estimates at 7-16 ft. water De. pth . .\' n :7.5( - ·2.3 Mean Estimates !It . 20-26 ft. Water [lepth
1/ _Metric tons of fioh per 50 sq. m. of ourface area. 2/ lnC<Jitllete data • ' i
3/ Average of 2 Observers estimates.
I)Jgalikthluk Bay
Ungalikthluk Bay Ungalikthluk Bay Nunavachak Bay .1 Mile west Ungalikthluk pt. East of Eagle Bay Eagle'~y ·
West Side, Tongue pt. TOgiak Bay, Mouth Aslqyukpak Spit Bight
Kulukak Bay
'lbgiak Bay 'lbgiak Bay 'lbgiak Bay 'lbgiak Bay
Nushagak Peninsula Nushagak Peninsula •
water Depth in Feet
20
10 25 15
16 20
2/ 2/
20
7 18 25
24
13 10 25 11
12 14
. .. ~
"' U1
-
\
11!:11-CV/201 (:t2J IIERR IIIG 1\Eilll\1. SIIIIVEY tKliiKSIIEET
' '· . Flight llo. .~_'~
1\lrcrart( \'Sill··
/
lla te :<,/;:,'r.J,, ~· Start Time O?: '15/'-11.1,
0 • •r . . . , , '11liB flight ·<'", I" '<·'I·. ; \Flight Duration• .: .
llccumlated 1/ ~ • I ,, ' i
\ , .. i
- \
End Time >·;!Hpll>.. Ohserver(s)_de/~.__:: ____ '. ' This flight A' 4YO ~~-
Cost• _11 Oudget l:111h! <· 11 I llccllllllated~f 7, .;( /S ~jl. .. - --·-.
I1
111I~1C I Sttner J/ _ll!!!!f!guU~~Ii 'II Jollf ff R.A.I. 1111115 · IICJAss fill••••• __lp .. nw COIIfllenls (tMII.It~nllfled fhlt
1 lire• • :~~!'CM~ Siiiilr-Reii:-I•r•~"'3f{ 2 1 2 scl111ols. Nl!llher. nssel
~11!!9_ s.o.u "''· ''l!L ar Lrt .. ., 1•11 I•SI (Jr;ui . lat•l •M~''""' •"·~~''"" '~'''"' "'..,•r l.e•••h Jh'6Fr·, '1~·1·1~ · .1:!2 ? --e- -&- ___l_r_ oro~ 110~ fr · .o- Wii!J -:?. iV S, ?, S I K. 7 '1' f) 'L'i'3 7 .e-- (/ o,rl-o-tl) : 1LL ? -fr. J!ill $.~.1- !:?'lt?bo• -lr _'j_?!.!_ Jl~~tl. ~t;;dCJ. L!J1 7ll3 fi4 IS) ~gSOl~ -8- 1.1.1~~ ~·J''iiZd~,',i?., \"'; 1lll. lj~ -6-- ..iQ. _}_ __ JZ!!!i. ~:::. 30o 13 313 £f31 -Ln.il' 3 &dL r-oo 1 lY.l_ ,1/ ./J-- D _2L S•·J~-~,,, iJ __:}_.!2_ I !lO~ /, 'W I. <t<l'> I ( i ~ u<f -&: ),Suo) JLL 3l'f ...:~t::.M 1 !>.?~bo~ -11·· ~ qgJ nKt. t:J soo y o.r; < c~.m) n Jc -if /0~ fO'i Zt5?,f•• -(J- 6~S' 1'160'1 ,.;;13'1 '/.;- 11''.1 ~ v~ t.) ('<1/Wfr. I d. A . (IS.hv) 1L J.,h · .v 2- ?>o lt3/,Yfol -u-- ,.,.- /.17'1 /1~'1 "'i'Tt.iK J <173~ -G-<- .;,mw· F:H~~.U~ t!lL '{/<) -fr I ____!}__ l/O,D04 -e- !) -7..,
171 ( I I I '_ . ...e- b 1 ' I'( '"W;;'\,...
Q_L 3/tl .L ~ .....:1-. t,~.dO·l _/"~, ..1!!2.-1,~'- l,frf -=§y? <), !W /,'J. 'i5'" -TJ- f;),oou\ tdfild __Jl__~ 7_f~ 5't11J · <( ),',2. 11 /d]JJIJ)
L :---- :::1 -- _::__ __, L "- ~2.~~ · -~ -.~~ /·- . --~- I Q -----(1~. I \'ol'l'fr$fol·' E}/1t1J;t.- 9~'t'3l}·tui/S Ro ;:: . \ . '''" - .;? f g ~ . . = ' -j)J, ¥d:ff-R s- -; m ~& -=> ~r.~~;~~.~~:Jf ~ ~ ~ . -- -----· ------· c ~"""'-··· 0 ~ ~ . . :::l ()
VJ ~ ()
~-8 U>
!/ I·Excellenl (ul•, no !larel 2•Good (llgllt r lpple, uneven lighting, easr
to see sct10ol') l"'h lr (light chop, SOtiM! _glue or shadows
relatively easy to spot 'chools) 4•ronr (rough seas, strong glne, dtrflcull
to s1•ol schools) - ..
2( S.O.II•less lhon ar eqo11l ta ~~>o2 ISIO rt21 - ftedh••grealer th•n 61111112, but leu lh•R or
eqo11l Ia 450o2(4,B44 n 21 l.uge .. greller l11an 45o.2
' :-:~~-:----_.._.~~-~~~~~ _:o:~~:~:-.. -~~.:;.,· :, .c-o-:;_.-,;:-.='=' - • :- · ,...-.;=. <;.,:--! "· ·~-'-~:. :-::~---=~._-:~--:~ _.... -:~~" !£=! -:_·-~..-_ .. _-_ -~~·-- ~ - .:.:_; .. ~~~N'tri #Jl:cbii t ·;.::.~~ .~/s~:t:t*'ri · :. -;;;.±- ... ~-;.. · -?,;·::'. ·--=· _.,__ '"'-·
0 0 0 0 0 0 0 0 0 0 0