The Hydrobiological Survey of Monterey Bay

During the spring quarter of 1928, Dr. Henry Bryant Bigelow, acting professor of oceanography at Harvard University visited Hopkins Marine Station and assisted in the teaching on the subject of oceanography.  The Oceanic Biology class that Bigelow instructed was announced in the Hopkins Marine Station Bulletin of 1928 with the following course description.

500. Oceanic Biology - The ocean as an environment of animals and plants; oceanography; adaptation of oceanic plants and animals; distribution; methods of marine exploration; fisheries problems and marine resources. A four weeks' course of three lectures weekly, with demonstrations, open to all students.  Required of students registered in Courses 511, 516, 541, 542.  2 units Bigelow (Hopkins Marine Station Bulletin, 1928).¹

Bigelow not only lectured to the class on oceanic biology, but took students on cruises aboard the California State Fisheries steamer "Albacore," demonstrating methods of oceanic investigation.  During that summer, as part of his visit, Bigelow, with the support of members of the Hopkins Marine Station, the Museum of Comparative Zoology of Harvard University, the Scripps Institution of Oceanography of the University of California, and the Division of Fish and Game, conducted a short but intensive hydrobiological survey of Monterey Bay.²

The project involved investigating two aspects of the waters of Monterey Bay, the hydrographic and the biological, with the importance directed on the latter. The seasonal and annual variations in the physical and chemical states and in the currents of the Monterey Bay would be studied, and the quantitative and qualitative changes, both annual and seasonal, in the pelagic flora and fauna were to be correlated with the hydrographic data.³

The survey entailed collecting data from various locations throughout the Bay.  At each location temperatures at different depths were gathered, and water samples collected for determination of nitrates, phosphates, silica and oxygen. Concurrently, in an effort to ascertain the composition of pelagic and bathypelagic flora and fauna, in association with the hydrography of the Bay, plankton hauls were conducted at comparable depths.⁴

While conducting this initial hydrobiological survey of the Monterey Bay, Bigelow urged the Division of Fish and Game and the Hopkins Marine Station to consider working together to extend the project. With Bigelow's encouragement the two institutions entered into a cooperative arrangement, which allowed for the research to continue.⁵

From the California Division of Fish and Game, EC Scofield was assigned the portion of the program associated with fisheries; most specifically a study of spawning and early life history of sardines. From the Hopkins Marine Station, Dr. Tage Skogsberg was selected to supervise the technicians assigned to the analysis of water samples and in handling of data collected. Beyond the supporting staff, the two institutions each provided $1,500 annually toward general expenses associated with the survey.⁶ A significant amount of the research effort was labor intensive which required weekly trips onboard the State Fisheries patrol boats, Albacore and Steelhead, to seven designated locations for the collection of water temperature data and seawater sample.

During the first three years of the program the collection of data was limited to the waters close to the Hopkins Marine Station. In 1932, with access to improved boating facilities, the program was extended considerably.  According to Skogsberg:

"The entire bay was included in our program and particular emphasis was placed on ascertaining the role played by the deep channel in the general hydrographical changes characteristic of the Bay. Seven stations were established. One was on the northern side of the channel; two were on the southern side; the remaining four, in a manner, triangulated the central channel." ⁷

With the inclusion of a large portion of the bay, a particular emphasis was directed toward understanding the role the Monterey Canyon played in the general hydrographical patterns of the Bay.⁸

1. Hopkins Marine Station Bulletin, 1928. Stanford University Bulletin.  Fifth Series, No. 48.  March 1, 1928.  Stanford University, California.
2. Annual Report of the President of Stanford University For The Thirty Seventh Academic Year ending August 31, 1928. Published by the University. Stanford University Bulletin. November 1928
3. Annual Report of the President of Stanford University For The Thirty Seventh Academic Year ending August 31, 1928. Published by the University. Stanford University Bulletin. November 1928
4. Ibid.
5. California. Dept. of Fish and Game The Department. (1921) (Report, Volumes 26-30).
6. Ibid.
7. Skogsberg, Tage (1932) Oceanographic work at the Hopkins Marine Station, Stanford University, for the year 1932. Transactions, American Geophysical Union, Volume 14, Issue 1, p. 221-222.
8. Ibid.

The Hydrobiological Survey ran for almost a decade (1929 to 1937), with those investigators supporting the research provided laboratory space at Hopkins Marine Station. Several scientific publications that resulted from the survey include Bigelow and Leslie (1930), Heath, Harold. (1930), Skogsberg (1936) and Skogsberg and Phelps (1946).

• Bigelow, H. B. and Leslie, M. (1930).  Reconnaissance of the waters and plankton of Monterey Bay, July, 1928. (Henry B. Bigelow and Maurine Leslie). Cambridge, Mass. : Printed for the Museum, 1930. p. 430-581 : ill., maps ; 25 cm. Bulletin of the Museum of Comparative Zoology v. 70, no. 5.
• Heath, H. (1930).  A connecting link between the Annelida and the Echiuroidea (Gephyrea armata).  Journal of Morphology, 49(1): 223-249.
• Skogsberg, T. (1936).  Hydrography of Monterey Bay, California. Thermal Conditions, 1929-1933. Transactions of the American Philosophical Society, New Series, Vol. 29, No. 1. 1-152.
• Phelps A. (1938). The Variation in the Silicate Content of the Waters in Monterey Bay, California, during 1932, 1933, and 1934 (Austin Phelps) Transactions of the American Philosophical Society New Series, Vol. 29, No. 2 (Mar., 1938), pp. 153-188
• Skogsberg, T. and Phelps A.  (1946). Hydrography of Monterey Bay, California. Thermal conditions, 1934–1937. Proc. Am. Phil. Soc., 90 (5) : 350–386.

The findings presented in Skogsberg (1936) and Skogsberg and Phelps (1946) were summarized by Raymond C. Anderson’s in his Master’s thesis, Thermal conditions in Monterey Bay during September 1966 through September 1967 and January 1970 through January 1971, as follows:

1. Bigelow and Leslie (1930)

Bigelow and Leslie conducted the first hydrobiological survey of Monterey Bay (Skogsberg (1936)). The variation with depth of temperature (as well as that of other physical parameters such as salinity and silicate at most stations) was obtained at 29 stations in the bay over the period of 30 June to 24 July 1928. The data were assumed to be synoptic and the horizontal distributions of sea surface temperature, temperature at depths of 10 meters and 100 meters, and the depths of the 9°C and 10 °C isotherms- were plotted. Vertical sections across the bay and along the canyon's axis were also contoured. From these plots it was concluded that upwelling tended to flow up the slopes of the sides of the canyon toward the canyon's head from a depth of at least 250 meters. Regarding horizontal circulation it was stated that an anticyclonic system existed at the mouth of the bay. This was attributed to the shoreward spread of the colder upwelled waters leaving a quiescent area of relatively warm light waters along the axis of the canyon. Assuming that such waters are to the right of the flow a clockwise circulation will be developed.

2. Skogsberg (1936) and Skogsberg and Phelps (1946)

An intensive study of thermal conditions was conducted during the years 1929 - 1937 by Hopkins Marine Station, These two reports constitute important background material for many of the subsequent studies of Monterey Bay. A considerable number of time series graphs based on monthly averages at stations in the southern part of the bay were considered representative of conditions throughout the entire bay. These graphs plus diagrams of vertical sections of temperature led to the following conclusions (among others): First, conditions in the southern end of the bay were dependent upon forces outside the bay. Second, according to Skogsberg (1936) an open meander in the bay's circulation represented a more or less deep bend in a side branch of the general coastal flow while a closed eddy with clockwise flow indicated a northerly coastal current. Finally, counterclockwise closed eddies were considered to result from a southerly coastal flow.31

Possibility of Future Sardine “Crop” Forecast Indicated By Scofield

By Jacqueline Rice

Monterey Peninsula Herald, Friday September 4, 1931

            Forecasting the supply of sardines available for commercial purposes two or three years in advance is a possibility predicted by Eugene C. Scofield of the California Bureau of Fish and Game who returned to Monterey Peninsula Sunday aboard the state fisheries 85-foot motorboat, “Bluefin” in the interests of the hydrobiological survey being conducted by Stanford University in conjunction with the state fish and game commission.

            Mr. Scofield left here in February cruising south and rounding the tip of Lower California at Cape San Lucas, into the gulf; then north to Eureka, going as far as 300 miles off shore.

To Extend Cruising Area

            The purpose of the cruise was to further the investigation which he has been carrying on since 1929 in an attempt to locate the maximum spawning area of the sardine- assuming that they spawn in the same season. Mr. Scofield says that the “Blue Fin” will have been equipped with wireless and lifeboats, making it still more practical for long trips. Leaving here in January he expects to cover an area of 400,0000 square miles which will probably end the cruising necessary for the survey.

            The work thereafter will consist of the establishment of stations within the maximum spawning area and the collection of larva in quantitative numbers during the spawning season, making it possible to forecast the success or failure of sardine fishing for two or three years in advance.

Spawning Area Outlined

            The gathering of data fort his work necessarily extends over a period of years and is of no value except when coordinated by successive experiments. Mr. Scofield now believes that the maximum spawning area is rather vaguely defined in the shape of the letter “S”  beginning south of Lower California and moving north to San Pedro, where it swings off shore to a point 150 miles to the west, turning north again for a short distance.

            Knowledge of the behavior of the sardine is vital in protecting the fisheries from depletion, and in preparing for future activity. This knowledge can be gained only thru painstakingly following the movements of the fish and their abundance from year to year. As it is almost impossible to catch the very small fish in numbers, study is made of the larva which hatch from the eggs, and float about freely before developing into the small fish.

Method Described

            The “Blue Fin” is equipped with electric winches and 15,000 feet of cable for making tows and catches . In gathering of larva a net made of fine silk, in the shape of a cone, six feet in diameter and 25 feet long, the roundmouth of which is held open by a one inch pipe, is used. This strains the water and gathers practically all the larger organisms such as eggs and larva, while the smaller mouth prevents the entrance of large fish and water organisms. Tows are quantitative, covering the same distance, at the same depth, speed, etc. to make them identical each time.

            One cruise just finished.  Mr. Scofield made 250 stations where he stopped to tow, afterward going through the catch and counting the eggs and larva one by one, before sending the rest of the material gathered to the Hopkins Marine Station for further study.

            Mr. Scofield expects to be at the Hopkins Marine Station until he starts his January cruise.  During the winter he will be working on the  survey of Monterey Bay being conducted by himself and Dr. Tage Skogsberg, a regular member of the staff of the station.

Scientists Invade Privacy of Monterey Bay Inhabitants

SARDINE LIFE SECRETS BARED BY SURVEY

Hydrobiologial Investigation Has Comprehensive Scope

Albert Campbell

Monterey Peninsula Herald Monday, October 1, 1934

Hydrobiology is the study of life in the water. Oceanography is a little more than that.  It includes not only the study of marine life but also ocean currents, the tides, the valleys and hills of the ocean “floor.” The charting of the surface. and even the chemistry of ocean water.  So you can see right away that this is going to be an interesting and even thrilling discourse.

Even if the hydrobiological survey of Monterey Bay which is being conducted by Hopkins Marine Station of Stanford University was not interesting, Dr. Tage Skogsberg, who is directing the survey, would make you like it.

Although the survey is not exclusively concerned with learning about the sardine, that is probably the phase of the work most interesting to the local people.  Other studies on the subject are being made in southern waters of the state.  The California Division of Fish and Game are cooperating with Stanford University in the survey.

What Survey Is “All About”

The first hydrobiological survey work, as it is now understood at the local station, was done in the summer of 1928.  That was not the first time local professors had ever thought of it, but it was during that summer that Dr. H. B. Bigelow of Harvard University visited the Hopkins Marine Station.  With the indispensable cooperation of the Division of Fish and Game, the visitors undertook to make a brief but very intensive hydrobiologial survey of the bay.  The launch “Albacore” was assigned to local duty for the survey.  Also, E. C. Scofield, scientist of the Division of Fish and Game, was assigned to assist Dr. Bigelow in the work.  Scofield continued to study the sardine in the southern part of the state. Dr. Skogsberg has seen that the survey continued here. It was upon his suggestion that the cooperative plan of sharing the initial expense and subsequent data gathering expeditions was formulated.  The “Albacore” continues to serve as the survey boat.  Laboratory work is done both at the Hopkins Marine Station and at the private laboratory of Dr. Skogsberg in his Carmel home.

Now, what kind of observations does a scientist make when conducting a hydrobiological survey? To begin with he takes the temperature of the water, not only at the surface but at varying depths.  There are seven “stations” in the bay and in the ocean for about 20 miles west of the bay at which temperatures are taken.  At five of these the temperatures are taken down to a depth of 500 meters. At one- that nearest Point Pinos – they test to 100 meters.  At the deepest, about seven miles north and west of Point Pinos, they test to 900 meters.  At this “station” water samples are taken at various depths by the use of a very ingenious “bottle” which closes at the desired depth and does not admit water from other depths as it is hauled to the surface.

And now, what does our scientist do with his water samples when he has them – and why?  First, he tests them for salinity- that is, he finds how salty they are.  This enables them to trace currents.  For instance: Suppose at station A he finds water of a given salinity at 900 meters and at station B finds the same salinity at 400 meters – it is possible that there is a current flowing between the two points.  Such a current would not only be travelling on a line between points but up or down a hill as well.  Of course, salinity is only an indicator in this connection and must be checked with other factors.

Secondly, our hydrobiological surveyor will test his water samples for phosphate content.  This is because the phosphates include many important plant nutrients.  Abundance of phosphate in a certain area would mean an abundance of a certain kind of plant food. And plants are food for small fish, including sardines – so you get the connection.

The third test is for silica content of the water.  Silica furnishes shell building material, so it is of importance to marine life even if there is no direct known bearing on the sardine’s life.  Abalone, for instance, would bot flourish in an area poor in silica.

Water temperature, Dr. Skogsberg believes, is probably the most important factor in regulating currents.  Warm water has a tendency to rise and cold water to go down-and of course such movements mean that other water has to “shove over” and make room.  Thus, currents develop.  IF you remember the famous the famous “thermo-syphon system” of the old-time flivver the principle should be quite clear to you.

Fish and Game Men Praised

One of the most satisfying things about the survey, Dr. Skogsberg declares, is the attitude of the leaders and workers of the Division of fish and Game. “They are very reasonable. They know that it is not possible to get big or sudden results from a study which takes many years to complete-which in fact can never be completed. They know that we can’t be honest and make definite statements, too.” The desire of “practical” men to get “results” from the survey shown by Dr. Skogsberg to be impossible of fulfillment.  “You can’t blame them, as they are interested in dividends, but the work of decades just simply can’t be pressed into a few years.”

Dr. Skogsberg has been assisted in the survey by Dr. Rolf Bolin, of Stanford University, who has given yeoman service in the trying work of the survey.  During the current summer, too, Mr. David Horsburgh, an undergraduate student who was taken a lively interest in the survey, has assisted with “taking the stations.”

Pioneer Work in Europe

The important fishing nations of Europe have long realized the need for supervision of the exploitation of the ocean resources.  Since the last century they have had boards of fisheries whose function is to make researches and advise legislators.  At first there was a prevailing optimism as to the “quick results” expected from these studies.  This, however, waned as the realization dawned that the factors of ocean study are enormous and that well founded data requires an outlay of time and patience that is, in the words of Dr. Skogsberg, “quite breath taking.” Though the Atlantic fishing nations are cooperating magnificently through an international association for oceanographic research, a cooperation that continued practically untrammeled during the World War, and though they have amassed an amazing fund of knowledge they are just as busy as ever and expect to be for many years to come.

The picture on the Pacific coast of America is not so encouraging.  Mexico does nothing along this line. Canada, with its comparatively short Pacific coast, not much. The states of Washington and Oregon are more active but have not shown the interest that might be wished.

Aside from the United States Coast and Geodetic Survey, which is principally concerned with the mapping of the coast and the currents along the shore, only the fish and game authorities and Hopkins Marine Station have gone into active systematic work in oceanography.  Due credit must also be given the Scripps Institution of Oceanography at La Jolla, a University of California unit.  And it is to be remembered that the only two available boats, aside from occasionally chartered private craft, are the “Albacore” and the “Bluefin,” patrol boats of the Division of Fish and Game.

Two General Types of Fish

Now we come to the point of possibly greatest interest to the reader – what has the survey discovered about the local commercial fish

There are two general types of fish. First, there are the “bottom” fish. A fine local example is the rock cod.  These fish do not migrate but spend all their lives feeding and spawning very near to the place of their birth.  It is thus comparatively simple to do study their life history – you don’t have to chase them all over the ocean as you do the sardine. Incidentally a species of “bottom” fish may be easily exterminated by ever persistent fishing in the once place where they are found.

The second general type of fish is the one which most interests us here. It is the pelagic or migratory type. The sardine, mackerel, and tuna come under this head. Migrations of fish are sometimes very extreme, covering thousands of fish miles, and there are two general kinds of migrations.  First, the fish must find food.  Second, they must find suitable places for spawning.  “The mark of a good fisherman, “says Dr. Skogsberg, “in his ability to tell at any time where fish are.” Of course, he may need more scientific assistance to do this.

Marine Station Studies May Aid Local Canneries

By William Millis

 Monterey Peninsula Herald, Monterey California, Thursday July 15, 1937

            Scientific planning  of the Monterey canning industry may be a result  of the hydrobiological survey of Monterey Bay which is now being carried on by members of the Hopkins Marine Station in Pacific Grove.

            Upon the basis of a five year investigation, a report of which has recently been published in the bulletin of the American Philosophical Society ,there may be found a predictable rhythm in the changes in the temperature of the water in the bay.

            A knowledge of these changes in temperature is important to the canning industry, because the coolness or warmness of the water is largely influential in determining the number  of fish coming near the shore, the report states. Over a period of years, local fishermen have had to go far from shore to make catches.

Study Not Final

However, Robert Leslie Bruckman, secretary of the Hopkins Marine Station  declares, the study is still indefinite, and must be continued further in order to be of commercial value.

The research work in the Hopkins laboratories is thorough and painstakingly, and never rushed through at a hurried pace.

Twenty-five students are enrolled at the summer session this year  at the Hopkins Marine Station, which began on June 24 and continues until the end of August.  The courseof study depends largely upon the special interest of each individual, who are all advanced students or college graduates.  The main course of the work of the school, however, centers around study of biological life of the waters of the Monterey Bay.

Small Fish—What Causes Them – Problem of Industry

Monterey Peninsula Herald, Monterey California, Friday February 28, 1941

            Is some strange shifting of the off-shore California currents the oceanographic cause of the increasing problem of “small fish” confronting Monterey’s sardine fishery?

            Are colder water temperatures and new current drifts forcing the great schools of fish to other feeding grounds? Are these the basic causes of the relatively unsatisfactory 1940-41 fishing season?

            Such are the questions many Monterey purse seine owners and cannery operators are raising these days, with the suggestion that a thorough oceanographic survey of California coastal waters is a first necessity for the fishery.

            But whether these questions are the correct questions, and could be easily solved by such as study, or whether it is actually a problem of over-exploitation, is the considered opinion of Dr. Tage Skogsberg, professor of marine biology and oceanography at the Hopkins Marine Station of Stanford University in Pacific Grove.

NO CURRENT CHANGES

Dr. Skogsberg – a tall, rugged Scandinavian and graduate of the University of Upsala in Sweden, with two decades of marine research in Europe and this country to his credit – is the author of a highly technical 150-page volume on the “Hydrobiology of Monterey Bay” based on a study from 1929-33 and published subsequently by the American Philosophical Society.

In it he studies the very questions Monterey’s fishery is raising today. And his answer, based on the best available information is: “It is very easy to blame the depletion of fish on currents, because that is extremely difficult to prove or disprove.  There may be and are slight changes on a day to day basis of inshore currents, but there are no radical current changes.”

“PERMANENT FEATURES”

“Currents are more or less permanent earth features, following known geographical formations, and the California Current (the southern end of the Japan current) is a big sweep that changes only in its intensity and not in its path  - it may be heavy one year and not another,” Dr. Skogsberg emphasized.

In his hydrograph report, the Stanford university scientist declared that current drifts make the spawning grounds for offshore in Southern California, the inshore “nursery,” and the northern coast fishing grounds make the major problem before the industry one of conservation.

“Conservation measures pertaining to the sardine should not be of a local nature, if we wish them to become effective, he said. “The amount of sardine taken in Southern California then becomes a concern of the industry in central California, and vice versa. Indeed, the problem then assumes an interstate and even an international aspect, since the Canadian catch of large-sized and heavy-spawning sardines in the far north will affect the success of the spawning in the southern California waters.”

SURVEY NEEDED

In the conclusions of his study, Dr. Skogsberg emphasized that "the hydrography, as well as the oceanography in general, of the sea off the coast of California is to a very large extent still an unexplored realm. This statement refers especially to the waters north of Point Conception.

"This lack of knowledge is especially deplorable on account of the fact that the California fisheries are very highly developed. Several of our most important fish species are at present under a very heavy strain of exploitation. Sound measures of conservation depend  on a sound knowledge of the biology of the species involved.

"In the case of marine forms, such a knowledge depends in its turn to a considerable degree on an advanced state in the knowledge of the hydrograph and general biology of the waters in which the species occur."

IT WOULD BE COSTLY

But before Monterey's fishermen decide that an oceanographic survey would be the automatic solution of all their problems, Dr. Skogsberg cautions them to consider the cost, time and labor involved.

"Oceanography work is too expensive," he said. "It cost the Woods Hole marine station $50,000 a year alone to maintain the Atlantis, the boat which they used for such  a survey. That figure Is larger than the total annual budget of the Hopkins station.

"And even if the California Division of Fish and Game were to undertake an oceanographic survey, it would take practically all of their time and all of their manpower before it was completed."

SCIENTISTS AT HOPKINS LABORATORY ALSO PRYING INTO SARDINES AFFAIRS

By William Mills

Monterey Peninsula Herald, Monterey California, Friday February 28, 1941

It’s curious what scientists what scientists will delve into.  Usually their concern is purely in the realm of pure science, and their purpose that of filing in ascertainable gaps in human knowledge.

And the question whether or not the results of the experimental research are of direct practical result in everyday life is not an issue in conceiving the investigation.

Such, without criticism, describes the general research conducted at Hopkins Marine Station of Stanford University, on Cabrillo Point beyond Monterey’s “Cannery Row.”

So it was with surprise that we discovered a little-known research project centered in the Marine Station,  which has immense potential effect upon California fish conservation in general and Monterey’s sardine fishery in particular.

The project is the “small sardine survey” of the Bureau of Marine Fisheries of the State Division of Fish and Game, which is being conducted in San Francisco and Southern California as well as here. The project is centered is centered at the California State Fisheries Laboratory at Terminal Island.

HERE IS TREND

Julius B. Phillips, research worker conducting the survey locally, makes his headquarters in the Marine Station. He reported that state research on the sardine fishery began in 1916, and thus parallels the growth of the industry locally.

For more than a decade, the local research has centered on the problem of “small fish,” the increasing proportion of young suitable for canning, which forced a temporary suspension of fishing and canning here early this season.

Through careful and regular sampling of catches, the survey has reached these present conclusions:

Over a period of years there has been a successive reduction in the size of fish taken: there has been a decreasing proportion of three-year maximum size sardines: there has been a growing number of first-year and second-year fish caught that are unsuitable for canning or reduction use.

“The thing is that too many of the fish are being caught,” Phillips commented.  “There is too intensive a fishery.”

SIGNIFICANT FIGURES

Significant for Monterey fishermen and cannery operators are these figures on the average length of fish caught locally, indicating a decreasing size each year:

Year                             Season to Dec. 15                               Season to Feb. 15

1929-1936                   9.70 inches                                          11.50 inches

1938-1939                   8.58 inches                                          9.50 inches

1939-1940                   9.00 inches                                          9.75 inches

1940-1941                   9.25 inches                                          9.75 inches

The first listing above, for 1929-1936, is a seven year average covering the 1929-30 throughout 1935-36 seasons.

Those figures are the result of a twice a week survey conducted throughout the fishing season, under which “samples” of approximately 50 sardines are taken from the catch of five different boats – with the canneries and seiners alternated – and then carefully measured.

They indicate Phillips, concluded, that “the fish have been subnormal for the last three years, and the only explanation is that the larger fish have been decimated.”