Circa: 1948-1949


Title Section No.


Trawl Log..............................2


Nansen Bottles.....................4

Fish Measurements..............5

Fish Tagging..........................6

Scale Samples........................7

Depth Recorder Traces.........8



A. Chief Scientist

1. Prepare or collaborate in preparation of cruise instructions.

2. Assign watches and quarters for scientists, collaborators, and guests.

3. Instruct all new personnel guests, etc., in mess schedule station bill.

4. Train new personnel in duties.

5. Coordinate collection of data between watches and between watches and bridge.

6. Maintain order board for instructions of each watch.

7. Prepare a full narrative report of each cruise.

B. Scientist in Charge of watch

1. Maintain all scientific records.

2. See that all the gear is prepared and operated in accordance with the plan; maintain

all scientific instruments.

3. When trawling, obtain data from catch and than turn catch over to crew for disposal.

4. Direct activities of his assistant.

5. Record lost and needed equipment in equipment log.

6. Preserve specimens as required and care for any live specimens.

C. Scientific Assistant

1. Assist in identifying, sorting, counting, measuring, sexing fish, taking scale samples, and maintaining records.

2. In trawling operations, assist with forward door, forward quarter rope and jilson on the net.

3. Assist in operating and recording the operation of all oceanographic instruments.

WFR 30 Aug. '48



Much time, money and trouble is directed toward an important operation--a trawl haul. It is thus imperative that trawling records be maintained to yield the maximum reliable and complete information consistent with human ability and existing conditions.

The trawling log is designed to furnish a standard procedure and methodical reminder for recording information. It is believed that provision has been made for all or most of the information pertinent to successful analysis of data collected by the net and associated operations.

Normally, or at least while log sheets are of common mimeograph paper, it would be best to write up the log with a soft pencil. Satisfactory results are obtained by using a #3.

In upper right hand corner, insert the year.

Other principal blanks are as follows:

1. Location of haul

"Cruise #" the current cruise designation

"Station #" this refers to a scheduled or extemporaneous station, includes a stop for one net haul (with repeats), hydrographic work (except BT cast), one special operation of any nature associated with scientific work where gear or apparatus is lowered or towed.

"Tow #" herein referred to as a haul. Several such may be made at one station, as decided by designers of the cruise.

"Date" refers to the day and month without resort to symbols, which are frequently confusing because not habitually used in every day life and require another mental conversion when the log keeper or analyst should be free from such processes. Write simply "23 Oct." or "18 Nov." as the date may be.

"Sub-area" refers to a common abbreviation employed in our designation of chartered areas. Sub-area XII H is shown as II H. For delineations of the various sub-areas into which the fishing grounds are divided, consult the statistical area a chart.

JRW 29 Oct. '48


"Unit area" refers to a rectangle 10 minutes of Latitude by 10 minutes of longitude. There are 36 of these unit-area rectangles in each full degree rectangle on the chart. The degree rectangle is designated by the latitude and longitude of its SE corner, so if these are latitude 42 and longitude 68, the rectangle is named 42-68. The unit areas in even 10-minute columns, are designated A, B, C, D, E, F, from left to right; and in even 10-minute rows, are designated 1, 2, 3, 4, 5, 6, from top to bottom. Every unit area in the extreme upper left of the degree rectangle is designated Al. Every unit area, bottom of second column, is designated B6. Example unit area: 42-68 B6. .

"Position" refers to the precise location, etc. of each station, haul, or stop, and is given in degrees and minutes of latitude and longitude. Positions are determined by LORAN fixes, celestial observation fixes, bearings on objects ashore, or bearings on buoys and lightships offshore: these are usually reliable. Radio bearings are not strictly reliable. Estimated positions derived from dead reckoning (abbreviation D. R.) are the least reliable of all, but must suffice when all other methods fail.

Note: The captain can usually estimate position within 5 miles, without LORAN assistance.

2. Hydrographic data:

"Depth" in fathoms, sounded or estimated.

"Bottom" type characteristics. Use data from chart. If other information is available, indicate same.

"BT #" record serial number of slide used

"Nansen #" copy cruise and station number used on the hydrographic sheet, which will be the same as trawling station number without the tow. Examples ALB-10-4. If no bottle lowering, write "none."

"Salinity" leave blank if bottle is lowered, otherwise write "none".

"Tmp. (btm)" insert only the bottom temperature from provisional reading of the BT slide.

JRW-29 Oct. '48


3. Meteorological

Use Beaufort scales and symbols where applicable.

"Wind" Direction and Force

"Current" Direction and Force (if determinable)

"Weather Conditions" Clear, Rain, etc.

"Sea" Calm, Slight, Rough, etc.

4. Tow

Duration and direction of

"Distance" Can be determined only from accurate fixes or other means.

"Speed" calculate from distance and time.

5. Gear

Write simple notation of the trawl net, as described in the cruise instructions. It will be sufficient to indicate simply "Census trawl", "Savings #1", "1-meter silk", "3-meter stramin" etc. as the case may be.

6. Use of data

Check "abundance" for census cruises, and write in other uses like "savings", "plankton", etc. when applicable.

It is recommended that the copy trawl log be filled ONLY after the original is completed, all measurements tallied off, and recording for the haul otherwise finished. A copy log begun when recording is incomplete may be forgotten, corrections neglected, etc.




The best time for making a Bathythermograph cast while the vessel is engaged in trawling work is upon arrival at a station. Ordinarily, the entire operation can be completed before the net is in the water and the ship ready for getting underway. This time is recommended for several reasons. 1. Usually a depth sounding is available 2. The biologists are ordinarily free from duties associated with trawl operation 3. Exact location is known.

The suggested routine for efficient casting operation is as follows:

1. Put over the surface thermometer.

2. Determine, from the sounded-depth, which BT should be used.

3. Check the instrument that will be used to make sure a clean, new slide is in place and the collar pulled all the way to the aft vanes.

4. Make the cast, return instrument to dresser, secure it with line provided.

5. Enter data on slide and in log.

6. When 5 minutes have elapsed, raise the surface thermometer and enter reading in the log.

7. Secure surface thermometer.

JRW 29 Oct. '48



Bathythermograph instruments ordinarily used on ALBATROSS III are classified according to depth range. Care should be taken to lower the instrument within these depth ranges as follows:

SHALLOW Depth to (illegible) fathoms

DEEP Depth to (illegible) fathoms

SUPER-DEEP Depth to (illegible) fathoms

Make every effort to use only the instrument of a class per trip. Example: if SHALLOW #6279 is first used, stick to this particular instrument throughout the cruise unless it demonstrates maladjustment or is lost.

Whenever a SUPER-DEEP instrument is lowered at a station, lower also a SHALLOW instrument to 20-25 fathoms. This procedure is for checking and obtaining more precise information on thermocline.

The instrument may be lowered gently into the water by hand. It is then dropped immediately without waiting for the air to escape.

NEVER leave the instrument unattended on the ship's rail. Shackle or unshackle with the instrument on deck or resting on the net.

ALWAYS mark the slide before dipping, with a sharp pointed hard pencil, and take care not to violate sacred areas of the slide. Sacred areas are those covered by numbers and identification titles of the grids, when these are superimposed.

AFTER the slide has been dipped, drain off excess lacquer by trailing edge of slide across absorbent paper and stow in slide box. Keep box cover closed.

In the bathythermograph log sheets, enter depth as the sounded or estimated depth at location of cast, in fathoms. This will be converted later in the laboratory. The purpose of recording sounded depth is for determining how close the traced depth comes to the bottom when instrument does not hit bottom.

JRW 29 Oct. '48



Bathythermograph glass slides are lightly smoked on one side only. This side is toward you when the cut corner is upper left.

Slides are inserted so that the cut corner is forward and to the left as the instrument points away from you. The smoked side is now ready to take tracings from the stylus.

Pulling the collar as far aft as possible depresses the stylus by releasing the trigger, under side of instrument. Watch this particularly on the SUPER-DEEP (900 feet) instrument.


Slides will be marked in a standard fashion. Note: (DIAGRAM)

1. The Cruise number (write ALB 10)

2. The slide number (series begins with "1" on each trip)

3. The time (use 24-hour system)

4. The date (day of month, roman symbol for month, year)

5. The instrument number (pressed in the brass somewhere, usually the nose)

On cruise #10, cast #18, 23rd October, about 6:22 a.m. with instrument #202, the following with appear on slide:

ALB - 10



22 x 43


JRW Oct. '48



Nansen bottles are designed to take water samples at various depths, and to record the water temperatures at these depths. Essentially, these bottles are open-ended tubes equipped with automatic closing valves.

Bottles are clamped to hydrographic wires lowered with the valves open. Thermometers are inserted in the frames with the mercury bulb ends below.

The first step in lowering bottles is to determine what depths are to be sampled. This information is a matter of standard practice--sampled depths depend upon depth of water at the station. When everything is in good working order, six bottles will ordinarily be sent down in an order reverse to their numbers.

For an example, it is assumed that the sounded depth is 90 fathoms or about 165 meters. Standard bottle depths for this sounding are 1 meter, 25 meter, 50 meter, 100 meter, 150 meter, and bottom. "Bottom" in this case will be 160 meters.

Prior to arrival at station, the hydrographic log sheet "A" will have been prepared. This preparation includes filling the appropriate headings and columns as follows:

1. "STATION NO." Is ALB-10-4 or similar

2. "LOCALITY" 42-68 B6 or similar

3. "DATE" is 23 Oct 1948 or similar

4. "EST. DEPTH" if no wire angle is anticipated, enter the standard depths 1-25-50-100-150-160.

5. "METER WHEEL" column is for depths that will show on meter wheel when bottles are attached.

6. "NANSEN NO." is for numbers of the bottles sent down to the various depths: #1 at 1, #2 at 25, etc.

7. "LEFT THERMOMETER" column will be used to enter the particular thermometer identifications. "NO." is for maker's number on the main stem or elsewhere. In routine, the tom weight is lowered until it just drags in the water, and will not swing clear when the ship rolls.

JRW 29 Oct. '48


Having set the meter wheel to zero, attach bottle #6. Since the distance between it and

#5 will be 10 meters, lower until wheel registers 10 meters. Attach bottle #5. Since the distance between bottle #5 and bottle #4 is 50 meters, add this amount to what the wheel already registers and lower wire to this figure, or 60 meters on the wheel. Attach bottle #4. Then 60 plus 50 is 110; attach #3. Then 110 plus 25 is 135; attach #2. Finally, 135 plus 24 is 159 and attach bottle #1.

At this point the mysterious, to some, is in reality completely simple. The wheel registers 159 meters, there is a bottle up in the air for the 1-meter level, and it is desired to place bottle #6 at the 160-meter depth.

In explanation, it is first necessary to understand the relationships involved. The "159" actually means that bottle #6 and bottle #1 are 159 meters apart, and will be so even if all the rest of the wire is payed out. Imagine it part of routine to attach a surface marker on the wire: the place for this would be 1 meter above bottle #1; or to be attached at working height after wire is let out to register 160 on the meter wheel. Bottle #1 would now be about 2 meters above the surface. Lowering it 3 meters more will put it 1 meter below the surface, as desired.

At this time, all condition are satisfied, as follows: Bottles are 1 meter, 25 meter, 50 meter, 100 meter, 150 meter, and 160 meter from the imaginary surface marker. Since the imaginary surface marker is at the surface, bottles are at estimated depths of 1 meter, 25 meter, 50 meter, etc.

What has actually happened is this: after attachment of the 1-meter depth bottle, 4 more meters of wire were payed out: 1 meter to place the imaginary surface marker at convenient height, 3 meters more to place the marker at the surface. The meter wheel will register 3 METERS MORE than the desired depth for bottle #6, or 163 meters.

Here is an invariable rule: if bottles are attached with the proper spacing between each, the final mark on the meter wheel will be the desired depth of bottom bottle plus distance between usual point of attachment and the surface. On ALBATROSS III this distance is about 3 meters. An understanding of this rule and its development will be helpful at those times when bottles are sent down to depths that do not include the 1-meter level: for example, 2 bottles, to the 150 and 16-meter depths.

JRW 29 Oct. '4


After raising bottles they are secured in laboratory racks, always in the same order.

Thermometer readings need not be made immediately; in fact, it is good practice to allow thermometers to stand an hour. Readings of the main stem the mercury column which breaks require checking several times, not only as a matter of routine, but also because the markings are frequently different between thermometers. Be sure to ascertain the value of full degrees, so as not to read 5.13 o instead of 15.13 o etc. Main stem readings are entered under T of the log sheet. Readings of the auxiliary thermometer, or short one, are entered under T on the log sheet. Ordinarily there is less variation between T readings of different thermometers than the T readings. That is because T measures temperature of the immediate surroundings.

When there is an appreciable stray of angle to the hydrographic wire, this should be measured and the amount entered in the appropriate box on the log. This stray value is used to calculate the most probable depth reached by each thermometer on the string.

Temperature readings taken with a surface thermometer should be entered in the log, with a notation of the thermometer number.

Bathythermograph casts associated with bottle stations should be noted on the log, also.

Nansen bottles are allowed to "soak" a full 5 minutes before sending the messenger down. (NOTE: A BT cast can be made in this time).

JRW 29 Oct. '48



There are two general methods being used. The first, when large numbers of fish of a species are to be measured, use the punch strip method. The second, when only a few fish of any species are to be measured, or when scale samples are being obtained, is the direct method.

Punch Strip method:

1. Determine the approximate length of the smallest and the largest fish of the species to be measured.

2. Select an aluminum strip that is long enough to extend over this complete range of lengths. (If the range of length of the species is too great to be covered by one punch strip, divide the fish into two groups, i.e. large and small, and consider each group separately.)

3. Slide the strip into the board to the point where the end of the tails of the smallest and of the largest fish can both be located over the strip.

4. With an awl, scratch a mark on the strip opposite some definite value on the graduated scale, such as the 30 centimeter or 50 centimeter mark. Also indicate on the strip which of the many points on the scale the scratch corresponds to.

5. Place the fish on the board, with the tip of its snout pressed firmly against the headboard and its tail extending along the aluminum strip.

6. With an awl, punch a small hole in the strip at the fork or the median of the tail.

7. After the lengths of all fish have thus been recorded, mark (with pencil) on the base of the strip, the Cruise No., Station No., Trawl No. And the species measured.

8. The total number of holes should be counted and the number recorded on the trawl log sheets.

9. The lengths should be tallied off by placing a guide strip of celluloid over the aluminum and counting the number of holes in each centimeter size group.

HAS 25 Oct. '48


Direct Measurement::

1. When small numbers of a particular species are to be measured or when scale samples in addition to length are to be obtained , the length of each fish is determined directly by placing each on the measuring board, reading off the fork or median length in centimeters and recording each length.

2. When fish are measured for scale samples, the length is recorded on the envelope.

3. When fish are measured for length alone, they are recorded on a length-frequency tally pad. A single mark of the pencil on the proper line will suffice to record each fish.

4. All fish are measured to centimeters only: i.e., fish whose lengths are from 61.0 centimeters to and including 61.9 centimeters or from 610 millimeters to and including 619 millimeters, are recorded as being 61 centimeter fish. Fish from 62.0 centimeters to and including 62.9 centimeters, or from 620 millimeters to and including 629 millimeters, are recorded as 62 centimeter fish, etc.

5. The numbers measured and/or scaled should be recorded on the trawl log and the actual measurements should be recorded on the length frequency tabulation sheet.

HAS 29 Oct. '48




Type of Tag to be Used

1/2" Celluloid discs (1 red, 1 white) and nickel pin.

Selecting the Fish to be Tagged

Only those fish in relatively good condition are to be tagged. Persons doing the tagging will indicate the condition (Grade) of each fish according to the following scale:

Grade 0. Lively fish having to twine marks, scratches or chaffed areas and no large patches of scales missing.

Grade 1. Lively fish but possessing any one and only one of the following injuries: twine marks, scratches, chaffed areas or large patches of scales missing.

Grade 2. Lively fish but possessing any two of the following injuries: twine marks, scratches, chaffed areas or large patches of scales missing.

No fish that is not lively shall be tagged and no fish, even though it is lively, shall be tagged if it possesses more than two of the above mentioned injuries.

It is possible that tows from shallow water and tows with relatively few fish in them may be the more productive of good quality fish.

Method of Tagging:

1. The metal pin should be inserted through the hole of the white disc and then through the operculum of the fish from inside to outside.

2. The pin should then be inserted through the red disc, care being taken to have the side of the disc with the legend on the outside.

3. Bend the end of the pin around, with fine-nose pliers, until it forms an effective barrier against removal of the disc. Have a 1/8" to 1/4' length of bare wire between the two discs to allow for growth of the operculum.

On small fish, the pin is often relatively too long to be neatly bent over. In such cases, the end of the pin should be cut off before bending it over.

HAS and RJB 29 Sept. '48


Data to be recorded

On each envelope the following data should be recorded:

1. The tag number.

2. The length of the fish in centimeters.

3. The grade of fish.

4. The Cruise No., Station No. and Haul No.

5. The species of fish.

6. The name of the person tagging the fish.

In addition, the time of day when the fish were placed in the live car and the time when the last fish had been tagged, should be recorded on one of the envelopes.

Scale Samples

Scales should be taken from each fish tagged and placed in the corresponding envelope. In taking scales from fish to be tagged, it is suggested that a departure from the usual scale taking method be followed, in that scales be limited to no more than a half dozen and be withdrawn with tweezers, rather than with a knife blade.

On the trawl log sheet, the species and number of fish tagged should be recorded along with the tag numbers used.

A "Record of Tagged Fish" sheet should be filled out when time is available.

HAS and RJB 29 Sept. '48




1. Measure the fork or median length of fish on measuring board and record length in centimeters on the scale envelope.

2. Scrape slime off the flank area of the body. In the case of haddock, pollock and cod, this area is between the 2nd anal fin and the lateral line. In the case of other groundfish, select the same general flank area.

3. Remove all slime and scales from the knife by rubbing the knife on a cloth.

4. Take a number of scales from the clean area with the knife blade and deposit them in the scale envelope between the blotting papers.

5. Record species, Cruise No., Station No., and Haul No. on first and last envelope in the group.

6. Make sure to record the number of these fish in the trawl log sheets and their lengths on the length frequency tabulation sheet.

HAS 25 Oct. '48




In addition to filling out the trawl log sheet, the scientist in charge of the watch should see that the depth recorder trace is marked at the beginning and end of each tow. This may be done by pushing the button on the depth recorder to make a continuous mark from top to bottom. This should be done at time of hook-up and haul-back and will effectively mark the beginning and end of tow. On the trace between these marks the cruise, station, and tow number should be written to label the marks for future reference.

This continuous trace for the cruise will be cut into sections for each tow and will be included with the other data for each cruise. If the trace is marked faithfully for each tow a continuous record of the depth for the tow, an indication of the type of bottom over which the tow was made, and the type and location of any tear-ups will be obtained.

LDS 5 May '49
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