NOAA Technical Memorandum NMFS-AFSC-23

Results of a 1988 Trawl Survey

of Groundfish Resources of the

Upper Continental Slope off Oregon

Norman B. Parks, Franklin R. Shaw, and Rick L. Henry

U.S. DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

National Marine Fisheries Service

Alaska Fisheries Science Center

October 1993
NOAA Technical Memorandum NMFS

The National Marine Fisheries Service’s Alaska Fisheries Science Center uses

the NOAA Technical Memorandum series to issue informal scientific and

technical publications when complete formal review and editorial processing are

not appropriate or feasible. Documents within this series reflect sound

professional work and may be referenced in the formal scientific and technical

literature.

The NMFS-AFSC Technical Memorandum series of the Alaska Fisheries Science

Center continues the NMFS-F/NWC series established in 1970 by the Northwest

Fisheries Center. The new NMFS-NWFSC series will be used by the Northwest

Fisheries Science Center.

This document should be cited as follows:

Parks, N. B., F. R. Shaw, and R. L. Henry. 1993. Results of a 1988 trawl

survey of groundfish resources of the upper continental slope off Oregon.

U.S. Dep. Commer., NOAA Tech. Memo. NMFS-AFSC-23, 164 p.

Reference in this document to trade names does not imply endorsement by the

National Marine Fisheries Service, NOAA.
NOAA Technical Memorandum NMFS-AFSC-23

Results of a 1988 Trawl Survey

of Groundfish Resources of the

Upper Continental Slope off Oregon

bY

Norman B. Parks, Franklin R. Shaw, and Rick L. Henry

Resource Assessment and Conservation Engineering Division

Alaska Fisheries Science Center

7600 Sand Point Way N.E., BIN C-15700

Seattle, WA 98115-0070

U.S. DEPARTMENT OF COMMERCE

Ronald H. Brown, Secretary

National Oceanic and Atmospheric Administration

Diana Josephson, Deputy Under Secretary
This document is available to the public through:

National Technical Information Service

U.S. Department of Commerce

5285 Port Royal Road

Springfield, VA 22161
Notice to Users of this Document 

This document is being made available in .PDF format for the convenience of users; however, the 

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copy format. 

iii

ABSTRACT

 The Alaska Fisheries Science Center (AFSC),, in cooperation

with the Southwest Fisheries Science Center (SWFSC), conducted a

bottom trawl survey of groundfish on the upper

off Oregon during November-December 1988. The

between 44°06' N lat. (Heceta Head) and 45°22'

 Lookout) between the depths of 183 and 1,280 m

continental slope

survey area was

N lat. (near Cape

(100 and 700 fm).

Sampling.-was conducted aboard the NOAA ship Miller Freeman and

included standard bottom trawl hauls, neuston net tows, standard

and deep oblique plankton net tows, and physical oceanographic

observations from 62, predetermined stations. This report

explains the sampling and analytical methods used and summarizes

the results of the bottom trawl survey. The report presents

environmental data, species composition, distribution, and

relative abundances of major species of fish,. Biomass,

population, and size composition estimates are presented for the

survey target species by depth stratum. Estimates are presented

mensuration report, position and catch listings for each haul,

catch rates of fish by depth stratum, population and biomass

estimates for principal species, and population size

compositions.
v

CONTENTS

INTRODUCTION. . . . . . . . . . . .

SURVEY METHODS . . . . . . . . . . .

Survey Area and Sampling Design .

Vessel and Fishing Gear . . . . .

Trawling Procedures' . . . . . . .

Catch Sampling Procedures .. . . .

Oceanographic Data Collection . .

Biological Data Collection. . . .

Data Analysis. . . . . . . . . . . . .

RESULTS . . . . . . . . . . . . . . . .

Haul, Catch, and Biological Data .

Temperature Data. . . . . . . . .

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Relative Density and Distribution of Species .

Biomass and Population Numbers .

Age and Size Composition . . . .

Length-Weight Relationship . . .

ACKNOWLEDGMENTS-. . . . .. . . . . .

TABLES . .

FIGURES ; .

CITATIONS .

APPENDIX A:

APPENDIX B:

APPENDIX C:

APPENDIX D:

APPENDIX E:

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Trawl Mensuration Report

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Haul and Catch Information . .

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Relative Abundance Of All Species . .

Population. and Biomass Estimates . . .

Population Size Composition . . . .

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vii

TABLES

Page

1. --Summary of characteristics and accessories for the

polyethylene Noreastern high-opening demersal trawl

used aboard the NOAA ship Miller Freeman during the

1988 West Coast upper continentalslope survey . . . . . .

2. --Summary of sampling by depth stratum during the 1988

West Coast upper continental slope survey . . . . . . .

3 .--Fish -species caught during the 1988 West Coast upper

continental slope survey . . . . . . . . . . . . . . . .

4. --Invertebrate species caught during the 1988 West Coast

upper continental slope survey . . . . . . . . . . . . .

5. --Summary of length data collected from fish species

caught during the 1988 upper continental slope survey .

6. --Summary of length observations from all fish-species by

depth stratum (m) for successful tows . . . . . . . . . .

7. --Summary of biological data collected by species.

Samples include data from good performance tows, poor

performance tows, and comparative tows . . . . . . . . .

8. --Summary of sablefish tagged during the survey . . . . .

9.--Mean CPUE (kg/km) by depth stratum of the 20 most

abundant groundfish and selected crab species caught

during the 1988 West Coast upper continental slope

survey . . . . . . . . . . . . . . . . . . . . . . . . .

10. --Sablefish biomass estimates with 90% confidence limits,

population numbers, mean lengths, and mean weights by

depth stratum . . . . . . . . . . . . . . . . . . . . . .

11. --Dover sole biomass estimates with 90% confidence,

limits, population numbers, mean lengths, and mean

weights by depth stratum, . . . . . . . . . . . . . . . .

12. --Arrowtooth flounder biomass estimates with 90%

confidence limits, population numbers, mean lengths,

and mean weights by depth stratum . . . . . . . . . . .

13. --Pacific hake biomass estimates with 90%. confidence

limits, population numbers, mean lengths, and mean

weights by depth stratum . . . . . . . . . . . . . . . .

24

24

25

28

29

30

32

32

33

34

34

35

35
viii

TABLES

No. Pace

14. --Shortspine thornyhead biomass estimates with 90%

confidence limits, population numbers, mean lengths,

and mean weights by depth stratum . . . . . . . . . . . 36

15. --Longspine thornyhead biomass estimates with 90%

confidence limits, population numbers, mean lengths,

and mean weights by depth stratum . . . . . . . . . . . 36

16. --Pacific hagfish, brown cat shark, spiny dogfish, deepsea skate, and Bering skate; estimates of biomass, mean

CPUE (kg/km), population numbers, mean lengths, and

mean weights by-depth stratum . . . . . . . . . . . . . 37

17. --Longnose skate, black skate, spotted ratfish, Pacific

halibut, and slender sole; estimates of biomass, mean

CPUE (kg/km), population numbers, mean lengths, and

mean weights by depth stratum . . . . . . . . . . . . . 38

18. --Petrale sole, English sole, deepsea sole, rex sole, and

unidentified poacher; estimates of biomass, mean

CPUE (kg/km), population numbers, mean lengths, and

mean weights by depth stratum . . . . . . . . . . . . .

19. --Blacktip poacher, blackfin poacher, California

slickhead, threadfin slickhead, and fangtooth;

estimates of biomass, mean CPUE (kg/km), population

numbers, mean lengths, and mean weights by depth

stratum . . . . . . . . . . . . . . . . . . . . . . . .

39

40

20. --Robust blacksmelt, threadfin cuskeel, unidentified

viperfish, Pacific viperfish, and American shad;

estimates of biomass, mean. CPUE (kg/km), population

numbers, mean lengths, and mean weights by depth

stratum . . . . . . . . . . . . . . . . . . . . . . .

41 

21. --California grenadier, Pacific grenadier, giant

grenadier, filamented grenadier, and threadfin sculpin;

estimates of biomass, mean CPUE (kg/km), population

numbers, mean lengths, and mean weights by depth

stratum . . . . . . . . . . . . . . . . . . . . . . . . 42

22. --Pacific cod, Pacific flatnose, walleye pollock,

lingcod, and blacktail snailfish; estimates of biomass,

mean CPUE (kg/km), population numbers, mean lengths,

and mean weights by depth stratum . . . . . . . . . . . 43
ix

TABLE'S

Page

23.--Longfin dragonfish, highfin dragonfish, unidentified

lanternfish, northern lampfish, and California

headlightfish; estimates of biomass; mean CPUE (kg/km),

population numbers, mean lengths, and mean weights, by

depth stratum . . . . . . . . . . . . . . . . . . . . . 

24. --Broadfin lanternfish, blue lanternfish, unidentified

snipe eel, slender snipe eel, and eulachon; estimates

of biomass, mean CPUE (kg/km), population numbers, mean

lengths, and mean weights by depth stratum . . . . . . .

25.' --Whitebait smelt, rainbow smelt, chinook salmon, Pacific

saury, and northern pearleye; estimates of biomass,

mean CPUE (kg/km), population numbers, mean lengths,

and mean weights by depth stratum . . . . . . . . . . .

26.--Shining tubeshoulder, king-of-the-salmon, twoline 

eelpout, soft eelpout, and snakehead eelpout; estimates

of biomass, mean CPUE -(kg/km), population numbers, mean

lengths, and mean weights by depth stratum . . . . . . .

27. --Bigfin eelpout, blackmouth eelpout; pallid eelpout,

black eelpout, and blackbelly eelpout; estimates of

biomass, mean CPUE (kg/km), population numbers, mean

lengths, and mean weights by depth stratum . . . . . . .

28. --Rougheye rockfish, Pacific ocean perch, aurora

rockfish, silvergray rockfish, and darkblotched

rockfish; estimates of biomass, mean- CPUE (kg/km),

population numbers, mean lengths, and mean weights by

depth stratum . . . . . . . . . . . . . . . . . . . . .

29. --Splitnose, greenstriped, widow,, rosethorn, and

shortbelly rockfishes; estimates of biomass, mean

CPUE (kg/km), population numbers, mean lengths, and

mean weights by depth stratum . . . . . . . . . . .

30.-- Canary, redstripe, redbanded, stripetail, and sharpchin

rockfishes; estimates of biomass, mean CPUE (kg/km),,

population numbers, mean lengths, and mean weights by

depth stratum . . . . . . . . . . . . . . . . . . . . . .

31. --Yellowmouth rockfish; estimates- of biomass, mean

CPUE (kg/km), population numbers, mean lengths, and

mean weights by depth stratum . . . . . . . . . . . .

4 4

45

46

47

48

49

50 

51

52
X

TABLES

Page

32. --Estimated age composition and mean length at age of

Pacific hake by year class. Results are presented by

depth stratum and for all strata-combined . . . . . . .

33.-- Estimated age composition and mean length at age of

darkblotched rockfish by year class. Results are

presented by depth stratum and for all strata combined .

53

55
xi

FIGURES

Page

l.-- Survey area showing the location of 57 successful

bottom trawl tows of the 1988 upper continental slope

groundfish survey . . . . . . . . . . . . . . . . . . .

-2.-- Mean bottom (BWT) and surface (SWT) water temperatures

by depth stratum during the 1988 upper continental

slope groundfish survey. . . . . . . . . . . . . . . . .

3.-- Distribution and relative abundance of sablefish during

the 1988 continental slope groundfish-survey . . . . . .

4. --Distribution and relative abundance of Dover sole

during the 1988 continental slope groundfish survey . . .

5 -Distribution and relative abundance of -arrowtooth

flounder during the 1988 continental slope groundfish

survey . . . . . . . . . . . . . . . . . . . . . . . . . .

6.--Distribution and relative abundance of Pacific hake

during the 1988 continental slope groundfish survey . .

7.-- Distribution and relative abundance of shortspine

thornyhead during the 1988 continental slope groundfish

survey.........................

8.--Distribution and relative abundance of longspine

thornyhead during the 1988 continental slope groundfish

survey. . . . . . . . . . . . . . . . . . . . . . . . .

9.--Distribution and relative abundance of spiny dogfish

during the 1988 continental slope groundfish survey . .

lO.-- Mean CPUE for six primary groundfish target species

shown by depth stratum . . . . . . . . . . . . . . . . .

ll.-- Mean CPUE (kg/km trawled) of five most abundant species

in each depth stratum (Circle size is directly

proportional to the total mean CPUE in each depth

stratum)........................

12.-- Shortspine and longspine thornyhead catch per unit

effort (no./km trawled) by depth. . . . . . . . . . . .

13.-- Shortspine thornyhead and longspine thornyhead size

composition and mean length by sex for each stratum and

60

61

62

63

64

65

66

67

68

69

70

71

for all strata combined . . . . . . . . . . . . . . 72-73
xii

FIGURES

No. Page

14. --Arrowtooth flounder and Pacific hake size composition

and mean length by sex for each stratum in which the

species were encountered and for all strata combined . . 75

15. --Sablefish and Dover sole size composition and mean

length by sex for each stratum and for all strata

combined...................... 76-77

16. --Estimates of Pacific hake population numbers by age

for all depth strata combined . . . . . . . . . . . . .

17. --Estimates of darkblotched rockfish population numbers

by age for all depth strata combined . . . . . . . . . .

18. --Mean length at age and calculated age-length curves

based he von Bertalanffy growth function,

(Ricker 1975: equation 9.9) for

darkblotched rockfish by sex for all depth strata

combined........................

19.--Length-weight relationships for sablefish by depth . . .

20. --Length-weight relationships for Dover sole by depth . .

21. --Length-weight relationships for shortspine thornyhead

bydepth.........................

22. --Length-weight relationship for arrowtooth flounder . . .

23. --Length-weight relationship for Pacific hake . . . . . .

24. --Length-weight relationship for darkblotched rockfish . .

78

79

80

81

82

83

84

85

86
INTRODUCTION

In 1988, the Alaska, Fisheries Science Center's (AFSC)

Resource Assessment and Conservation Engineering (RACE) Division

and the Southwest Fisheries Science Center's (SWFSC) Coastal

Fisheries Division conducted a cooperative survey of the

groundfish resources off the coast of Oregon between Heceta Head

and 'Cape Lookout. Both science centers are part of the National

Marine Fisheries Service (NMFS). Primary objectives were to

examine sablefish, (Anoplopoma fimbria) size, age,. sex ratio, and

reproductive condition as a function of bathymetric distribution;

evaluate the application of area-swept bottom trawl and egg

production survey methods to the continental slope demersal

community; and define the reproductive biology, food habits, and

habitat characteristics of key shelf species including sablefish,

Dover sole (Microstomus [pacificus), shortspine thornyhead

(Sebastolobus alascanus), and arrowtooth flounder (Atheresthes

stomias). Other objectives were to describe the physical

characteristics (temperature, oxygen, salinity, and current speed

and direction) of the continental slope demersal habitat, the

upper slope groundfish community and how it varies with depth,

and juvenile sablefish movements through tagging.

This was the second survey of the upper continental slope

fishery resources off the coast of Oregon. The preceding survey

was conducted in 1984 (Raymore and Weinberg, 1990) to determine

the feasibility of utilizing bottom trawls and vertically

deployed strings of sablefish traps to assess abundance,'
2

geographic and bathymetric distribution, and biological

characteristics of the major groundfish species. inhabiting the

upper continental slope. The present survey replicated the

southern part of the 1984 survey.

This report is intended to document the methods used and the

results obtained from the 1988 survey. Included are summaries of

catches, distribution, abundance, and size composition for all

major components of the community, as well as analyses of agelength and length-weight relationships of selected species. In

the report, we discuss the species composition of the upper slope

community and how that composition changes over the 1,100 m depth

range studied. Results of investigations into histology,

pathology, reproductive biology, food habit studies and

ichthyoplankton are being reported elsewhere.
SURVEY METHODS

Survey Area and Sampling Design

The area surveyed included about one-quarter of the

International North Pacific Fisheries Commission (INPFC) Columbia

statistical area from Heceta Head, Oregon (44°06'N), to near Cape

Lookout, Oregon (45°22'N), between the depths of 183 and 1,280 m

(100 and 700 f-m) (Fig. 1). The survey area was stratified into

six depth intervals: 183-366 m, 367-549 m, 550-732 m, 733-914 m,

915-1,097 m, and 1,098-1,280 m (100-200 fm, 201-300 fm, 301-400

fm,. 401-500 fm, 501-600 fm, and 601-700 fm). Trawl- stations were

placed randomly along parallel east-west tracklines which were

spaced 16.7 km (9 nautical miles, nmi) apart. The number of

stations was allocated proportionally to the trackline length

across each depth stratum as follows:

Linear distance along 'Number of stations allocated

trackline within depth stratum to trackline section

113.0 km (7.0 nmi) 1

13.1-26.0 km (7.1-14.0 nmi) 2

126.1 km (14.1 nmi) 3

Vessel and Fishing Gear

The NOAA ship Miller Freeman is 66.5 m (215 ft) long overall

and has 2,300 continuous horsepower. -The vessel was equipped

with two net reels, hydraulically powered split trawl winches,

and had interior spaces for processing the catch and laboratories
4

for collecting and analyzing biological and oceanographic data.

The vessel was staffed and equipped to operate 24 hours a day.

A polyethylene Noreastern high-opening bottom trawl equipped

with mud-sheep roller gear was used to sample the groundfish

community (Table 1). A small mesh liner was used in the codend

to assure retention of small fish. SCANMAR trawl mensuration

systems were used to monitor wing spread, door spread, headrope

height, and trawl depth throughout the survey. Useful

information, however, was acquired from just 16 survey tows

because acoustic signals from the instruments could not be

received when fishing deeper than 1,100 m.

Trawling Procedures

Sampling began on the southernmost trackline and the vessel

continuously worked, northward during the course of the survey.

If untrawlable terrain was encountered at a pre-selected station,

a search for favorable ground was conducted within a 9.3 km

(5 nmi) radius of the original site. If a trawlable area was not

located after a reasonable search effort, the site was abandoned

and the vessel proceeded to the next assigned trawl station.

Once suitable bottom was located, the trawl was deployed and

sufficient time was allowed while the vessel moved slowly ahead

for the net to settle to the bottom (l0-55 min, depending on

depth). At depths shallower than 732 m (400 fm), the trawl was

towed for 30 minutes after settling using a scope ratio of

approximately 2.5:1. Sixty-minute hauls were made at deeper
stations using scope ratios of approximately 2:l or less. Towing

speed was approximately 3.7 km/hour (2 knots). This is slower

than the standard 5.5 km/hour (3 knots) used during the 1984

slope survey and during triennial surveys; but was considered

necessary to keep the trawl fishing on bottom during the deeper

tows when warp lengths began to approach winch capacities and low

scope ratios had to be used. When the net was snagged, badly or

significantly damaged, the trawl-haul was considered

unsatisfactory and the station was repeated or abandoned,

depending on the time available. On the other hand, a trawl haul

was considered satisfactory if a minor snag or untrawlable bottom

was encountered, but no gear damage resulted and over half of the

tow had been completed. 

Catch Sampling Procedures 

Standard RACE catch sampling procedures were followed as

described by Hughes (1976) and Smith and Bakkala (1982). Allcatches were released from the-codend directly onto the sorting

table, sorted into baskets by species, counted, and weighed..,

Invertebrates were identified to species as time and expertise

permitted.After catches were, weighed and counted, biological

data and specimens were collected.
6

Oceanographic Data Collection

Sea surface temperature (SST) was obtained with a bucket

thermometer at all sampling stations. Bottom water temperature

(BWT), as well as salinity and temperature profiles of the entire

water column, were obtained at all survey stations using a

Seabird conductivity-temperature-depth (CTD) probe. Seawater

samples for oxygen and salinity were collected at selected

stations. Oxygen concentrations were determined by titration

using a modified Winkler method.

Biological Data Collection

Samples of all fish species were measured to characterize

how their size composition varies with depth. Length

measurements for up to 100 specimens of each of the primary

target species were collected by sex per haul. Otoliths were

collected from sablefish, Dover sole, arrowtooth flounder,

shortspine thornyhead, Pacific hake (also known as Pacific

whiting)(Merluccius productus), and darkblotched rockfish

(Sebastes crameri). Three biological sampling strata, 183-549 m,

550-914 m, and 915-1,280 m (l00-300 fm, 301-500 fm, and 501-700

fm), were established to assure that samples were taken from the

full range of depths. Otoliths were collected from stratified

samples of five fish per sex/centimeter interval per biological

sampling stratum.

Whole ovaries were collected from sablefish, Dover sole,

arrowtooth flounder, shortspine thornyhead, darkblotched
7

rockfish, and Pacific hake for fecundity studies. Samples of

ovaries were also collected from sablefish, Dover sole, and

shortspine thornyhead for histological verification of the

maturity stages assigned at sea.

Sablefish that were captured in good condition were tagged

and released alive to support a continuing study of their

movements. Sablefish were placed in live tanks with-circulating

sea water. Usually within 15 minutes of completing the haul,

viable sablefish were measured, tagged in a padded tagging

cradle, and released. Each fish was tagged with a single anchor

tag implanted just below the first dorsal fin (see methods in

Shaw 1984).

Additional biological collections were made for a variety of

studies. Stomach samples were collected from sablefish, Dover

sole, deepsea sole, (Embassichthys bathybius), longspine

thornyhead (Sebastolobus altivelis), and shortspine thornyhead

for an ecological study. Pacific hake samples were collected for

viral and parasite studies. Tissues of major organs were taken

from Dover sole, arrowtooth flounder, Pacific hake, shortspine

thornyhead, sablefish, and selected crabs for pathology studies.

Because the cruise occurred before most groundfish spawn,

ichthyoplankton samples to collect eggs and larvae were taken

only at approximately one-third of the bottom trawl stations. A 

1

 Major organs included tissues from the liver, gills, skin,

muscle, gall bladder, kidney, intestine, stomach, and gonad.
8

thorough survey of the ichthyoplankton was conducted during the

later NOAA vessel David Starr Jordan cruise 89-3 (16 February -

 5 April 1989) which replicated the NOAA vessel Miller Freeman

cruise 88-9 station pattern. Miller Freeman ichthyoplankton

sampling included nekton tows, 200 m bongo tows, and deep bongo

tows. Neuston tows were conducted with a Manta net frame, a 45.4

kg weight, and a 505μ mesh net. Tows were 15 minutes in duration

with a wire angle ranging between 20° and 25°. Standard (200 m)

bongo tows were taken obliquely to 212 m using a CalCOFI 71 cm

bongo net frame, a 34.O kg weight, and a 505μ mesh net. The net

maintained a descent rate of 50 wire-meters per minute and was

allowed to stabilize for 30 seconds at terminal depth. Haul-back

was maintained at a rate of 20 m per minute. Wire angles ranged

between 38° and 51°. Deep bongo tows were conducted with a 505μ 

mesh net on a 71 cm CalCOFI frame, equipped with a 56.7 kg

weight, and a 9040 series Plessey TD (temperature-depth) sensor.

Descent rates were approximately 35 m. per minute and ascent rates

were approximately 14 m per minute. The net was lowered to

within 50 m of the sea bottom and maximum depth was limited to

1,250 m.
Data Analysis 

Four standard analyses are routinely performed on RACEsurvey. data. These provide:.

(1) estimates of the species. biomass, 

(2) estimates of the total population numbers,

(3) estimates of the population size composition, and

(4) estimates of the population age composition.

It should be noted that estimates of biomass and population are

based on the following assumptions:

1. All fish in the path of the trawl are caught. There is

no significant effect from avoidance or herding. The

catchability coefficient is assumed to equal one.

2. The entire fishable resource is vulnerable to capture by

the trawl used.

Partial availability of the species to the sampling gear and

catchability of less than 100% will result in conservative

estimates of abundance when using-the area-swept survey method.

These, assumptions are probably. weakest for sablefish, larger

specimens of which are known to avoid capture by trawls (Parks

1973).

Biomass and population numbers for species of interest are

estimated by the area,-swept method (Gunderson and Sample 1980).

Mean CPUE is expressed in terms of kg/ha to derive a biomass

estimate and in terms of no./ha, to obtain a population estimate.

Size composition within a stratum is calculated by apportioning.

the, estimated total population numbers into sex-centimeter
10

intervals based on haul-by-haul length frequency estimates which

have been weighted by CPUE and summed over all hauls in the

stratum., Age composition estimates are derived by applying an

age-length key to the size composition estimate.
11

RESULTS

Haul, Catch, and Biological Data

Of the 62 bottom trawl stations scheduled for this survey,

57 were successfully sampled (Fig. 1). Table 2 summarizes the

type and number of samples by depth stratum and the size of each

stratum in square kilometers.

The fishing dimensions of the trawl were measured during 24

tows. The complete trawl mensuration report is presented in

Appendix A. After removing the five unsatisfactory tows, the

mean wing spread for the survey trawl was calculated to be

14.7 m. This value was used to represent the mean net width for

the area-swept biomass calculations.

A total of 85 fish species representing 32 families were

caught (Table 3). Table 4 lists the nearly 40 invertebrate.

species encountered, representing 12 classes.. Appendix B

presents detailed station information for each haul and catch

weights of major fish and invertebrate species for all

satisfactory, trawls.

Table 5 lists the number of length observations and the

observed length ranges for each of the 84 fish species measured

(total of 34,918 observations).. Table 6 summarizes the length

observations from satisfactory tows by depth stratum.

Table. 7 presents a summary of biological data collected.

A total of 120 sablefish were tagged and released during the

course of the survey (Table 8).
12

Temperature Data

Surface and bottom temperatures were collected at all 70

stations fished. Mean bottom temperatures ranged from 3.3°C in

the deepest depth stratum to 6.6°C in the shallowest depth

stratum (Fig. 2.). Mean surface water temperatures ranged from

11.5° to 11.7C.

Relative Density and Distribution of Species

Figures 3-9 show the relative densities (kg/km trawled) at

each station for the six primary target species and spiny dogfish

(Saualus acanthias) which was included because of its high

abundance in the shallow stratum.

The 20 most abundant species in each stratum were ranked in

order of mean catch per unit effort (CPUE) expressed in kg/km

trawled (Table 9). For all depths combined, spiny dogfish was by

far the most abundant species taken (118.5 kg/km) with virtually

all of that taken in the shallowest depth interval (183-366 m).

Sablefish and Dover sole were next in abundance with overall mean

CPUEs of 51.7 and 49.0 kg/km, respectively, followed by longspine

and shortspine thornyheads (28.5 and 25.3 kg/km, respectively).

Among the target species, sablefish, longspine thornyhead,

and Dover sole had the highest CPUEs across the various depth

strata (Fig. 10). Nearly all of the target species were found in

all depth strata. Longspine thornyhead was not caught in the

shallowest stratum and arrowtooth flounder was encountered only

in the two shallowest strata with relatively low catch rates
13

(less than 12 kg/km. trawled),. Sablefish was the most abundant

species in the 550-732 m stratum (179.3 kg/km) and either the

second or third most abundant species in all other strata except 

the shallowest (Table 9, Fig. 11). Dover sole was the most

abundant species in the 367-549 m stratum (100.3 kg/km) and its

-catch rates exceeded 19.5 kg/km trawled in all but the deepest

stratum. Longspine thorny head was the most abundant species

(117.3 and 85.0 kg/km) in the 733-914 and 915-1,097 m strata,

respectively. It was-also the second most abundant species in

the 'deepest stratum. Shortspine thornyhead was the third most

abundant species in the three shallowest depth strata and was

most abundant (38.2 kg/km) in the 550-732 m stratum.,

The CPUE of shortspine thornyhead declined gradually with

depth. This decline in CPUE is more apparent in terms of number

than it is in terms of weight (Fig. 12) because the average size

of shortspine thornyhead increases with depth (Fig. 13).

Longspine thornyhead catch rates begin to increase at about

550 m and by 700 m they eclipse catch-rates for shortspine

thorhyhead. Although both species occur over the entire depth

range of the survey (183-1,280 m), shortspine thornyheads are

generally more abundant at depths below about 460 m, whereas

longspine thornyheads are more.-abundant at depths greater than

about 680 m.

As expected, the dominant species in the catch changed among

depth strata. In the shallowest stratum (183-366 m);spiny
14

dogfish were most abundant with a mean CPUE of 452.8 kg/km,

(Table 9, Fig. 11). Splitnose rockfish (Sebastes diploproa),

shortspine thornyhead and Dover sole were the next most abundant

(25.6, 24.8, and 23.1 kg/km, respectively). Less important in

the shallowest stratum were Pacific hake (15.6 kg/km) and

sablefish (9.0 kg/km).

In the 367-549 m stratum, Dover sole, was the most abundant

of all groundfish taken with a mean CPUE of 100.3 kg/km.

Sablefish and shortspine thornyhead were next with mean CPUEs of

32.0 and 27.9 kg/km, respectively, followed by Pacific ocean

perch (Sebastes alutus) (20.9 kg/km), longnose skate (Raja

rhina) (12.9 kg/km), Pacific hake (12.3 kg/km), and arrow-tooth

flounder (11.8 kg/km).

In the 550-732 m stratum, sablefish with a CPUE of

179.3 kg/km was the most abundant groundfish species, followed by

shortspine thornyhead, Dover sole, and longspine thornyhead

(38.2, 36.1, and 34.8 kg/km, respectively). Grooved Tanner crab

(Chionoecetes tanneri) -was the second most abundant species taken

in this depth interval (39.9 kg/km).

In the 733-914 m stratum, longspine thornyhead was the most

abundant (117.3 kg/km) of all grounhfish. Sablefish, Dover sole,

and shortspine thornyhead (54.0, 24.9, and 16.2 kg/km,

-respectively) were the next most abundant groundfish in this

stratum. Grooved Tanner crab and giant grenadiers (Albatrossia

pectoralis) followed at 6.6 and 6.4 kg/km, respectively.
15

In the 915-1,097 m stratum, longspine thornyhead continued

to predominate with a mean CPUE of 85.0 kg/km. Next in abundance

were sablefish and Dover sole (31.6 and 19.7 kg/km,

respectively): Giant grenadiers and shortspine- thornyhead were

also abundant in this depth stratum (18.4 and 16.0 kg/km,

respectively).

In the <deepest stratum (1,098-1,280 m), longspine thornyhead

-again had the highest mean CPUE (37.4 kg/km) of the six-target

species, although giant grenadier catch rates were higher

(41.7 kg/km). Sablefish (19.8 kg/km), shortspine thornyhead

(8.5 kg/km) and Dover sole (3.0 kg/km) became less important in

this stratum. Other important species included Pacific grenadier

(Corynhaenoides acrolepis) and grooved Tanner crab (18.7 and

9.3 kg/km, respectively).

Appendix C lists all fish species in order of mean catch

rate for each depth stratum.

Biomass and Population Numbers

The largest biomass estimates calculated for commercially

important fish species encountered during this survey were for

sablefish, Dover sole, longspine thornyhead, shortspine

thornyhead, Pacific hake, and arrowtooth flounder with total

biomass estimates of 18,504, 17,552, 10,218, 9,044, 2,973, and

1,900 metric tons (t), respectively' (Tables 10-15).

The sablefish biomass estimate was the greatest of the

commercially important species over all depths but 81% of the
1 6

estimated biomass for sablefish was found shallower than 733 m

Table 10). Fifty-six percent of its biomass was concentrated in

the 550-732 m depth stratum.

The Dover sole biomass estimate was the largest of the

commercially important species in the 367-549 m stratum, where

67% of its estimated biomass occurred. Seventy-nine percent of

the estimated biomass for Dover sole was found shallower than

550 m (Table 11).

All of the estimated biomass for arrowtooth flounder was

found in the two shallowest strata, 183-549 m (Table 12).

Seventy-two percent of the biomass was observed in the 367-549 m

stratum.

Nearly all (97%) of the estimated Pacific hake biomass was

split evenly between the two shallowest strata (Table 13).

Pacific hake had the third highest biomass estimate of the

commercially important species in the 183-366 stratum after

shortspine thornyhead and Dover sole, and the fifth most abundant

species in the 367-549 m stratum behind Dover sole, sablefish,

shortspine thornyhead, and Pacific ocean perch.

Eighty-six percent of the estimated shortspine thornyhead

biomass occurred in the three shallowest depth strata (Table 14).

Its peak biomass was seen in the 367-549 m stratum (36%), where

it ranked third behind Dover sole and sablefish, respectively.

Ninety-seven percent of the estimated biomass for longspine

thornyhead was found within the 550-1,280 m depth strata. Fifty-

-I
two percent of its biomass was found in the 733-914 m depth.

stratum (Table- 15), where the estimated longspine thornyhead

biomass was the largest of all the commercially important fish.

Tables 16-31 provide summaries of biomass estimates for all

non-target species. A full listing of program BIOMASS for each

of the target species, including biomass, population numbers,

mean CPUE, and mean individual weight for each stratum and for

all strata combined- is located in Appendix-D..

Age and Size Composition

Length frequency distributions for sablefish, Dover sole,

arrowtooth flounder, Pacific hake, shortspine thornyhead, and

longspine thornyhead by depth stratum and for all strata combined

are presented in Figures 13-15. Sablefish mean lengths ranged

from 43.6 cm in the shallow depth stratum to 58.9 cm in the

deepest stratum, Dover sole from 33.2 cm to 45.6 cm, and

shortspine thornyhead from 22.1 cm to 45.8 cm, respectively. All :

three of these species exhibit a marked increase in mean length

as depths increases. In all three of these species, the largest

increase in mean length occurred between the second and third

depth stratum. Arrowtooth flounder, Pacific hake, and longspine

thornyhead showed little change in mean length in the depth

strata where they were taken. Size composition estimates for

each of the target species. for the entire survey area are

provided in Appendix, E.
18

Although age structures were collected,.for sablefish,

darkblotched rockfish, shortspine thornyhead, Dover sole, Pacific

hake, and arrowtooth flounder, only Pacific hake and darkblotched

rockfish otoliths had been assigned ages at the time this report

-was prepared.-

Small otolith sample sizes for Pacific hake (n = 213) -and

darkblotched rockfish (n = 157) reduce the certainty of age

composition estimates but afford us some relatively rare

information about these species in the late fall. Because of

these small sample sizes, a single age-length, key was applied to

estimates of the population size composition for each species to

calculate age compositions for each depth zone.

A Pacific hake growth curve is not presented because there

were so few age classes that a meaningful age-length relationship

could not be developed. The majority of Pacific hake were 8 year

olds, members of the 1980 year class (Table 32, Fig. 16). This

year class was dominant in all depth strata, although 4 year olds

(1984 ‘year class) and 11 year olds (1977 year class) also

contributed significantly to the population. These year classes

have been previously observed as stronger than average (Dorn

et al. 1991) and were again the predominant year classes in the

summer of 1989 in the Columbia INPFC area (personal communication

K.L. Weinberg, AFSC, NOAA, 7600 Sand Point Way NE, Seattle, WA

98115, unpublished data).
19

observed ages for darkblotched rockfish ranged from 1 to

68 years. The strongest year class was from the 1985 spawning,

representing 13% of the estimated population (Table 33, Fig. 17).

The 1985 year class dominated the shallowest stratum (183-366 m)

making up 22% of that population, but was not found in the deeper

-stratum (367-549 m). All of the youngest fish (1, 2, and

3 years) were found only in the shallower stratum. In the deeper

stratum, the 1979 through 1982 year classes were most abundant,

making up over 53 % of the population in that stratum. Nichol

(1990) found similar depth variability in age compositions off

Oregon with primarily l-3 year olds in 74 fm, 3-5 year olds in

108 fm, and 6-9 year olds in deeper than about 150 fm.

Figure 18 presents the darkblotched rockfish age-length

relationship by sex for all depth strata combined. Length at age

for both males and females are very close to those found by

Nichol (1990)% Mean length-at-age data was fit to a

von Bertalanffy growth curve which indicates asymptotic lengths

of 38.0 cm for males and 39.7 cm for females. Most growth is

completed by about age 12.

Length-Weight Relationship

The length-weight relationships (sexes combined) for

sablefish, Dover sole, arrowtooth flounder, Pacific hake,

shortspine thornyhead, and darkblotched rockfish are shown by

depth interval in Figures 19 through 24.
20

Sablefish less than 60 cm had similar length-weight

relationships in all three depth intervals, whereas the weight at

length decreased with depth for sablefish greater than 60 cm

(Fig. 19).

In the shallowest interval (183-549 m), Dover sole sizes

weighed less at all-lengths than their counterparts in the deeper

zones (Fig. 20). The length-weight relationships in the two

deeper intervals were similar, although in the deepest zone (915-

1,280 m) fish less than 46 cm outweighed those in the middle

depth zone while fish greater than 46 cm weighed less than those

in the middle interval.

Shortspine thornyhead from the shallowest depth interval

weighed less at all sizes than did fish from the two deeper

intervals, which displayed nearly identical length-weight

relationships (Fig. 21).

Arrowtooth flounder, Pacific hake, and darkblotched rockfish

length-weight data were taken only from the shallowest depth

interval (Figs. 22, 23, and 24).
21

ACKNOWLEDGMENTS

We would like to thank all of the, cruise participants

including Paul Raymore, Tom Dark, Linda Cherepow, Mark Wilkins,

David Roetcisoender, and Tom Wilderbuer of the Alaska Fisheries

Science Center (AFSC); William Flerx, Ronald Dotson, Kenneth

Bliss, Eric Lynn, Kriste Miller, and Wayne Samiere of the

Southwest Fisheries Science Center (SWFSC). We would also like

to express our, appreciation to the crew of the R/V Miller Freeman 

(especially to the-survey technicians), to David Woodbury (SWFSC)

Tiburon for ageing the darkblotched rockfish samples, to the AFSC'

age unit for determining hake ages, and to Craig Rose and David.

Roetcisoender.(AFSC) for the net mensuration data collection,

analysis, and report.
2 3

TABLES

25

Table 3 .--Fish species caught during the 1988 West Coast upper continental

slope survey.

Family and Species" Common Name'
26

Table 3. --Continued.

28

Table 4 .--Invertebrate species caught during the 1988 West Coast upper

continental slope survey.

Phylum and Class’ Species’

Porifere

Hexactinellida

Cnidaria

Hydrozoa

Anthozoa

Unidentified sponge

Unidentified hydroid

Unidentified anemone

Unidentified sea pen

Scyphozoa

Echinodermsta

Asteroidea

Unidentified jellyfish

Ctenodiscus crispatus

Unidentified sea star

Brisaster latifrons

Luidia foliata 7 - Thrissacanthras penicillatus

Pteraster tesselatus

DiDlopteraster multif3les

PoranioDsis inflate

Holothuroidea

Ophiuroidea

Echinoidea

Mellusca

Gastropoda

Cephalopoda

Scotoplanes theeli

Psolus sp.

Unidentified sea cucumber

Ophiura sarsi

Allocentrotus fragilis

Unidentified sea urchin

Neptunea sp.

Bathvbembix bairdii

Unidentified snail

Unidentified nudibrench

Opisthoreuthis californiana

Berryteuthis magister

Unidentified squid

dofleini Octopus

OCtOPUS L

Unidentified octopus

Arthropoda

Cruscacea Pandalus iordani

Pandalus Platyceros

Chionoecetes tanneri

Lithodes couesi

- - Paralomis multispina

Looholithodes foraminatus

Unidentified crab

Chordata

Ascidiacea Unidentified tunicate

Unidentified salps

’ Nomenclature from Morrii, Abbott, and Haderlie (1980).
Table 5.--Summary of length data collected from fish species caught during the 1988 upper

continental slope survey.
30

Table 6. --Summary- of length observations from all fish species by

depth stratum (m) for successful tows.
'31
Table 7.--summary of biological data collected by species.

performance tows,

Samples include data from good

poor performance tows, and comparative tows.
Table 9.--Mean CPUE (kg/km) by depth stratum of the 20 most abundant groundfish and

selected crab species caught during the 1988 West Coast upper continental slope

survey.

w

W
Table 10. --Sablefish biomass estimates with 90% confidence limits, population numbers,

mean lengths, and mean weights by depth stratum.

Table 11. --Dover sole biomass estimates with 90% confidence

mean lengths, and mean weights by depth stratum.

limits, population numbers,
Table 12. --Arrowtooth flounder biomass estimates with 90% confidence limits, population

numbers, mean lengths, and mean weights by depth stratum.

Table 13. --Pacific hake biomass estimates with 96% confidence limits, population numbers,

mean lengths, and mean weights by depth stratum.
Table 14.--Shortspine thornyhead biomass estimates with 90% confidence limits', population

numbers, mean lengths, and mean weights by depth stratum.

W

Table 15. --Longspine thornyhead biomass estimates with 90% confidence limits, population

numbers, mean lengths, and mean weights by depth stratum.

38

Table 17. --Longnose skate, black skate, spotted ratfish, Pacific

halibut, and slender sole; estimates of biomass, mean

CPUE (kg/km), population numbers, mean lengths, and

mean weights by depth stratum.




43









53
54

Table 32. --Continued.

56

Table 33. --Continued:
57

Table 33. --Continued.
5 9

FIGURES
60

Figure l.-- Survey area showing the location of 57 successful

bottom trawl tows of the 1988 upper continental slope

groundfish survey.
Figure.2. --Mean bottom (BWT) and surface (SWT) water temperatures

by depth stratum during the 1988 upper continental

slope groundfish survey.




Figure 7.--Distribution and relative abundance of shortspine

thornyhead during the 1988 continental slope

groundfish survey.
Figure 8. --Distribution and relative abundance of longspine

thornyhead. during the 1988 continental slope

groundfish survey.
Figure 9 .--Distribution and relative abundance of spiny dogfish

during the 1988 continental slope groundfish survey.

Figure ll.--Mean CPUE (kg/km trawled) of five most abundant species in each depth stratum

(Circle/size, is directly proportional to the total mean CPUE in each depth

stratum).

Species key:

Dogfish = spiny dogfish Longnose = longnose skate POP

Dover = Dover sate LST = lonspine thornyheed Sable

= Pacific ocean perch SST

k sablefish

= shortspine thornyhead

Giant = giant grenadier Pacific m Pacific grenadier Splitnose = splitnose rockfish

Tanner = grooved Tanner crab
Figure 12. --Shortspine and longspine thornyhead catch per unit

effort (no./km trawled) by depth.





78

Figure 16. --Estimates of Pacific hake population numbers by age

for all depth strata combined.

Figure 18. --Mean length at age and calculated age-length curves

based on the von Bertalanffy growth function,

L = L,[l-e (Ricker 1975: equation 9.9) for

darkblotched rockfish by sex for all depth strata

combined.






87

CITATIONS

Dorn, M.W., R.D. Methot, E.P. Nunnallee, and M.E. Wilkins. 1991.

Status of the coastal Pacific whiting resource-in 1990.

U.S.Dep. Commer., NOAA Tech Memo. NMFS F/NWC-204, 97 p.

Eschmeyer, W. N., E. S. Herald, and H. Hammann 1983. A field

guide to Pacific Coast fishes of North America. Houghton

Mifflin Co., Boston, MA., 336 p.

Gunderson, D. R., and T. M. Sample. 1980. Distribution-and

abundance of rockfish off Washington, Oregon, and California

during 1977. Mar. Fish. Rev. 42(3-4):2-16.

Hughes, S. E. 1976. System for sampling large trawl catches of

research vessels. J. Res. Board ‘Can. 33:833-839.

Morris, R. H., D. P. Abbott, and E. C. Haderlie.. 1980.

Intertidal Invertebrates of California. Stanford Univ.

Press, 690 p;

Nichol, D. G. 1990. Life-history examination of darkblotched

rockfish (Sebastes crameri) off the Oregon coast.

M.S. Thesis. Oregon State University, Corvallis, OR, ,124 p.

Parks, N. B. 1973. Results of comparative trawl and trap

fishing off Oregon for sablefish, Anoplopoma fimbria. Mar,

Fish. Rev. 35(9):27-30.

Raymore, P. A., Jr., and K. L. Weinberg. 1990. 1984 spring and

autumn surveys of Pacific West Coast upper continental slope

groundfish resources. U.S. Dep. Commer., NOAA Tech. Memo.

NMFS F/NWC-179, 196 p. Available from Natl. Tech. Info.

Serv., 5285 Port Royal Road, Springfield, VA 22161, as

PB90-207812.

Ricker, W. E. 1975. Computation and interpretation of, biological

statistics of fish populations. Bull. Fish. Res. Board Can.

191, 382 p.

Robins, C. R. 1991. Common and scientific names of fishes from

the United States and Canada, Fifth Edition, Am. Fish. Soc.,

Special Publ. 20, 183. p.

Shaw, F. R. 1984. Data report: results of sablefish tagging in

waters off the coast of Washington, Oregon, and California,'

1979-83. RACE Division, Alaska Fish. Sci. Ctr., 7600 Sand

Point Way N.E., BIN C15700, Seattle, WA 98115.

Smith, G. B., and R. G. Bakkala. 1982. Demersal fish resources

of the eastern Bering Sea: Spring 1976. NOAA Tech. Rep.

NMFS SSRF-754, 129 p.
-89

APPENDIX A

Trawl Mensuration Report

Appendix A presents the trawl mensuration report for the

1988 West Coast upper continental slope groundfish survey.

Table A-1. --Trawl, mensuration data from Miller Freeman cruise

88-9.

Figure A-l. --Polyethylene Noreastern trawl with disc and chain

roller gear, wing spread measurements at depth.

Figure A-2. --Polyethylene Noreastern trawl with standard roller

gear, wing spread measurements at depth.

Figure A-3. --Polyethylene Noreastern wing spread measurements

with disc and chain roller gear versus standard.

roller gear.
90

APPENDIX A

Trawl Mensuration Report

Miller Freeman Cruise 88-9

Prepared by

Craig Rose

Conservation Engineering Task

Scanmar trawl mensuration systems were used to monitor wing

spread, door spread, headrope height and trawl depth during the

1988 AFSC and SWFSC Cooperative Groundfish Survey of the Upper

Continental Slope. This survey was carried out aboard the R/V

Miller Freeman between Heceta Head and Cape Lookout, Oregon.

Polyethylene Noreastern trawls were used throughout. For most

survey tows, a heavy, continuous roller gear consisting of rubber

discs (20 cm diameter) strung on heavy chain was used. At the

end of the survey, some comparative tows were made using the

lighter standard roller gear, made up of 36 cm bobbins separated

by rubber spacers.

Useful information-was acquired for 24 tows, 16 with the

disk footrope and 8 with the standard roller gear (Table A-l).

While both data sets contained considerable variability, neither

showed a consistent pattern of change with depth that could be

characterized with these small sample sizes (Figs. A-l and A-2).

While all of the tows with standard roller gear showed

consistent behavior while on bottom, several disc footrope tows

could be considered abnormal. Tows 40, 43, 46, and 57 all showed

indications of the gear snagging bottom obstructions. This

usually involved a rapid decrease in door and wing spread

followed by a widening as the gear released. Tow 40 was probably
91

the worst in that the net never assumed what would be considered

a normal towing configuration. Tow 43 was terminated early when

one of the doors hung up. This resulted in a widening of the

wing spread at the end of the tow.

Another phenomenon that occurred with the disc footrope

performance could be associated with the footrope digging, into

the softer substrate, collecting mud in the codend. This

resulted in a steady decrease in net and door-widths as well as

height throughout tows 41, 46, and 58.

A comparison between the wing &read of the two trawl

configuration types is presented in Figure A-3. The data points

represent pairs of tows at the same station. The trawl with the

disc footrope had a smaller wing spread in all cases, probably

due to an increase in drag from harder bottom contact.

Mean wing spreads were 16.2, m with the standard rollers and

14.1 m with the small discs. It would be more appropriate for

use as in area-swept calculations to remove those tows affected

by snags. In that case, the net width of the disc footrope trawl

averaged 14.7 m.

Figure A-l.--Polyethylene Noreastern trawl with disc and chain roller gear, wing spread

measurements at depth.
Figure A-2. --Polyethylene Noreastern trawl with standard roller gear, wing spread

measurements at depth.

9 7

APPENDIX B

Haul and Catch Information 

Appendix. B contains the computer listing generated from the

PACE program DRAG/LOG& Latitudes and longitudes are indegrees,

minutes, and fractions of minutes. Gear depth is in meters,

distance fished is in kilometers, and catches are in kilograms.

Performance of 0 indicates a satisfactory tow and performance of

7 indicates a unsatisfactory tow with a ripped net. All hauls

were made using the Noreastern otter trawl with 20 cm disc/chain

footrope.

Table 8-1 Continued.



APPENDIX C

Relative Abundance Of All Species

Appendix C is comprised of the computer listing generated

from RACE program RANK. All fish encountered during the 1988

West Coast upper continental slope groundfish survey have been

ranked in order of their relative abundance measured in CPUE

Tables are presented by depth stratum and for all strata

combined.

Table C-l. --Rank order of relative abundance (kg/km) of fish for

the 183-366 m depth stratum.

Table C-2. --Rank order of relative abundance (kg/km) of fish for 

the 367-549 m depth stratum.

Table C-3. --Rank order of relative abundance (kg/km) of fish for

the 550-732 m depth stratum.

Table C-4. --Rank order of relative abundance '(kg/km) of fish for

the 733-914.m depth stratum.

Table C-5. --Rank order of relative abundance (kg/km) of fish for

the 915-1,097 m depth stratum.

Table C-6. --Rank order of relative abundance (kg/km) of fish for

the 1,098-1,280 m depth stratum.

Table C-7. --Rank order of weighted relative abundance (kg/km) of

fish for all depth strata combined.














123

APPENDIX D

Population and Biomass Estimates

Appendix D is comprised of the computer listings generated

from the PACE program "BIOMASS". Estimated population totals and

their respective biomass estimates, measured in metric tons, for

the target species of the 1988 West Coast upper slope survey are

presented. The estimates are listed by stratum codes. The

stratification scheme is as follows:

stratum 200 = 183 - 366 m

stratum 300 = 367 - 549 m

stratum 400 = 550 - 732 m

stratum 500 = 733 - 914 m

stratum 600 = 915 - 1,097 m

stratum 700 = 1,098 - 1,280 m

all strata = 183 - 1,280 m

Table D-1. --Sablefish biomass and population estimates by depth 

stratum and for the entire survey area.

Table D-2. --Dover sole biomass and population estimates by depth

stratum and for the entire survey area.

Table D-3. --Arrowtooth flounder biomass and population estimates

by depth stratum and for the entire survey area.

Table D-4. --Pacific hake biomass and population estimates by

depth stratum and for the entire survey area.

Table D-5. --Shortspine thornyhead biomass and population

estimates by depth stratum and for the entire survey

area.

Table D-6. --Longspine thornyhead biomass and population estimates

by depth stratum and for the entire survey area.






APPENDIX E

Population Size Composition

Appendix E is comprised of computer listings generated from

the RACE program BIOMASS. Population size composition estimates

are presented by sex-centimeter interval for each depth stratum

and all depth-strata combined.

Table E-l. --Sablefish population size composition estimates by

sex and size group for each depth stratum and for all

depth strata combined.

Table E-2. --Dover sole population size composition estimates by

sex, and size group for each depth stratum and for all

depth strata combined.

Table E-3. --Arrowtooth flounder population size composition

estimates by sex and size group for each depth

stratum and for all depth strata combined.

Table E-4. --Pacific hake population size composition estimates by

sex and size group for each depth stratum and for all

depth strata combined.

Table E-5. --Shortspine thornyhead population size composition

estimates by sex and size group for each depth,

stratum and for all depth strata combined.

Table E-6. --Longspine thornyhead population size composition

estimates by sex and size group for each depth

stratum and for all depth strata combined;
132

Table E-l .--Sablefish population size composition estimates by sex and size group

for each depth stratum and for all depth strata combined.
133

Table E-l. --Sablefish continued.
134

Table E-l .--Sablefish continued.

Stratum 550-732 m
Table E-l .--Sablefish continued. 
136

Table E-l. --Sablefish continued.
137

Table E-l .--Sablefish continued.
138

Table E-l .--Sablefish continued.













152

154

156

158

Table E-5 .--Shortspine thornyhead continued.

All strata combined

160

Table E-6 .--Longspine thornyhead continued.
161

Table E-6.--Long/spine thornyhead continued.
162

Table E-6. --Longspine thornyhead Continued.
163
164

Table E-6. --Longspine thornyhead continued.
RECENT TECHNICAL MEMORANDUMS

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National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22167.

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YANG, M-S. 1993. Food habits of the commercially important groundfishes in the Gulf of Alaska

in 1990, 150 p. NTIS number pending.

KINOSHITA, R. K., and J. M. TERRY. -1993. Oregon, Washington, and Alaska exports of edible

fishery products, 1992, 52 p. NTIS No. PB93-226652.

REEVES, J. E. 1993. Use of lower minimum size limits to reduce discards in the Bristol Bay red

king crab (Paralithodes camtschaticus fishery, 16 p. NTIS No. PB93-226187.

SYRJALA, S. E. 1993. Species-specific stratification and the estimate of groundfish biomass in

the Eastern Bering Sea, 20 p. NTIS number pending.

PELLA, J., M. HOFFMAN, S. HOFFMAN, M. MASUDA, S. NELSON, and L. TALLEY. 1993. Adult

sockeye and pink salmon tagging experiments for separating stocks in northern British Columbia

and southern Southeast Alaska, 1982-l 985, 134 p. NTIS No. PB93-226660.

SEASE, J. L., J. P. LEWIS, D. C. MCALLISTER, R. L. MERRICK, and S. M. MELLO. 1993. Aerial

and ship-based surveys of Steller sea lions (Eumetopias jubatus) in Southeast Alaska, the Gulf of

Alaska, and Aleutian Islands during June and July 1992, 57 p. NTIS No. PB93-226025.

FISCUS, C. F. 1993. Catalogue of cephalopods at the National Marine Mammal Laboratory, 183

p. NTIS No. PB93-226676.

KINOSHITA, R. K., A. GREIG, L. E. QUEIROLO, and J. M. TERRY. 1993. Economic status of

the groundfish fisheries off Alaska, 1991, 94 p. NTIS No. PB93-197861.

PEREZ, M. A., and W. B. MCALISTER. 1993. Estimates of food consumption by marine mammals

in the Eastern Bering Sea, 36 p. NTIS No. PB93-191195.

BERGER, J. D. 1993. Comparisons between observed and reported catches of retained and

discarded groundfish in the Bering Sea and the Gulf of Alaska, 89 p. NTIS No. PB93-184711.

HARRISON, R.C. 1993. Data report: 1991 bottom trawl survey of the Aleutian Islands area,144 p.

NTIS No. PB93-186237.

LIVINGSTON, P. A., A. WARD, G. M. LANG, and M-S. YANG. 1993. Groundfish food habits and

predation on commercially important prey species in the eastern Bering Sea from 1987 to 1989,

192 p. NTIS No. PB93-184703.

KINOSHITA, R. K., and J. M. TERRY. 1993. Oregon, Washington, and Alaska exports of edible

fishery products, 1991, 47 p. NTIS No. PB93-159101.

KARINEN, J. F., M. M. BABCOCK, D. W. BROWN, W. D. MACLEOD, JR., L. S. RAMOS, and J.W.

SHORT. 1993. Hydrocarbons in intertidal sediments and mussels from Prince William Sound,

Alaska, 1977-1980: Characterization and probable sources, 69 p. NTIS No. PB93-159093.

WING, B. L. 1993. Winter oceanographic conditions in the eastern Gulf of Alaska, JanuaryFebruary 1986, 53 p. NTIS No. PB93-158335.