/ 1 ^L"-i../~£~*\^ -'. CALIFORNIA FISH 45142 STATE OF CALIFORNIA DEPARTMENT OF NATURAL RESOURCES DIVISION OF FISH AND GAME SAN FRANCISCO, CALIFORNIA EARL WARREN GOVERNOR WARREN T. HANNUM DIRECTOR OF NATURAL RESOURCES FISH AND GAME COMMISSION H. L. RICKS, President Eureka LEE F. PAYNE, Commissioner Los Angeles W. B. WILLIAMS, Commissioner Alturas DOM A. CTVITELLO, Commissioner Sacramento HARVEY HASTAIN, Commissioner Brawley EMIL J. N. OTT, Jr., Executive Secretary Sacramento BUREAU OF FISH CONSERVATION A. C. TAFT, Chief San Francisco A. E. Burghduff, Supervisor of Fish Hatcheries San Francisco Brian Curtis, Supervising Fisheries Biologist San Francisco L. Phillips, Assistant Supervisor of Fish Hatcheries San Francisco George McCloud, Assistant Supervisor of Fish Hatcheries Mt. Shasta D. A. Clanton, Assistant Supervisor of Fish Hatcheries Fillmore Allan Pollitt, Assistant Supervisor of Fish Hatcheries Tahoe R. C. Lewis. Assistant Supervisor, Hot Creek Hatchery Bishop J. William Cook, Construction Estimator San Francisco C. W. Chansler, Foreman, Yosemite Hatchery Yosemite Wm. Fiske, Fish Hatchery Man, Feather River Hatchery Clio Leon Talbott, Foreman, Mt. Whitney Hatchery Independence A. N. Culver, Foreman, Kaweah Hatchery Three-Rivers John Marshall, Foreman, Lake Almanor Hatchery Westwood Ross McCloud, Foreman, Basin Creek Hatchery Tuolumne Harold Hewitt, Foreman, Burney Creek Hatchery Burney C. L. Frame, Foreman, Kings River Hatchery Fresno Edward Clessen, Foreman, Brookdale Hatchery Brookdale Harry Cole, Foreman, Yuba River Hatchery Camptonville Donald Evins, Foreman, Hot Creek Hatchery Bishop Cecil Ray, Foreman, Kern Hatchery Kernville Carl Freyschlag, Foreman, Central Valley Hatchery Elk Grove S. C. Smedley, Foreman, Prairie Creek Hatchery Orick G. S. Gunderson. Fish Hatchery Man, Sequoia Hatchery Exeter E. W. Murphy, In Charge, Fall Creek Hatchery Copco Joseph Wales, District Fisheries Biologist Mt. Shasta Leo Shapovalov, District Fisheries Biologist San Francisco William A. Dill, District Fisheries Biologist Fresno BUREAU OF GAME CONSERVATION J. S. HUNTER. Chief San Francisco Gordon H. True, Jr., Assistant Chief San Francisco Donald D. McLean, Economic Biologist San Francisco Carlton M. Herman, Parasitologist San Francisco Rov M. Wattenbarger, Supervisor Los Banos Refuge Los Banos Russell M. Reedy, Supervisor Imperial Refuge Calipatria Ralph R. Noble, Supervisor Suisun Refuge Joice Island John R. Wallace, Supervisor, Predatory Animal Control San Francisco O. R. Shaw, Supervising Trapper Salinas Gerald McNames, Supervising Trapper Red Bluff BUREAU OF GAME FARMS AUGUST BADE, Chief Yountville E. D. Piatt, Superintendent, Los Serranos Game Farm Chino BUREAU OF MARINE FISHERIES RICHARD VAN CLEVE, Chief San Francisco S. H. Dado, Assistant Chief San Francisco W. L. Scofield, Supervising Fisheries Researcher Terminal Island Frances N. Clark, Supervising Fisheries Researcher Terminal Island Donald H. Fry, Jr., Supervising Fisheries Researcher Terminal Island J. B. Phillips, Senior Fisheries Researcher Pacific Grove Paul Bonnot, Senior Fisheries Researcher Stanford University W. E. Ripley, Senior Fisheries Researcher Stanford University Geraldine Conner, Fisheries Statistician Terminal Island (Continued on inside back cover) California Fish and Game "conservation of wildlife through education" Volume 31 SAN FRANCISCO, JULY, 1945 No. 3 TABLE OF CONTENTS Page In the Service of Their Country 78 Program of the Bureau of Marine Fisheries Richard Van Cleve 80 The Kettleman Hills Quail Project Ben Glading, R. W. Enderlin and Henry A. Hjersman 139 A New Fish Screen for Hatchery Use J. H. Wales 157 t Reports 160 California Fish and Game is a publication devoted to the conservation of wild- life. It is published quarterly by the California Division of Fish and Game. All material for publication should be sent to Brian Curtis, Editor, Division of Fish and Game, Ferry Building, San Francisco 11, California. The articles published herein are not copyrighted and may be reproduced >in other periodicals, provided due credit is given the author and the California Division of Fish and Game. Editors of newspapers and periodicals are invited to make use of pertinent material. Subscribers are requested to notify the Division of Fish and Game, Ferry Build- ing, San Francisco 11, California, of changes of address, giving old address as well as the new. 45142 * In "Che ^ertiice of 'Cheir Countrji Now serving with the armed forces of the United States are the following 149 employees of the California Division of Fish and Game, listed in order of entry into the service: Morton N. Rosen Albert King E. L. Macaulav E. R. Hyde George Werden, Jr. E. A. Johnson Henry Bartol Edson J. Smith John F. Janssen, Jr. Richard Kramer Arthur Barsuglia George Metcalf James F. Ashley William Jolley Rudolph Switzer Jacob Myers Charles McFall Lloyd Hume John E. Fitch William H. Sholes, Jr. James Reynolds Paul Gilloglev Ralph Beck Charles Cuddigan James H. Berrian Edward Dolder John Woodard Bob King Ross Waggoner John Canning William Richardson William Plett John Finigan Trevenen Wright John A. Maga Elmer Doty William Dye Lester Golden Richard N. Hardin Lawrence Rubke Virgil Swenson Harold Dave Howard McCullv J Austin Alford Belton Evans Willis Evans James Hiller Robert Terwilliger Eugene Durnev Charles W. Kanio Howard Shebley Donald Tappe Richard S. Croker J. G. McKerlie Robert Kaneen Elmer Lloyd Brown Douglas Dowell William Roysten Dean L. Bennett John Chattin C. L. Towers Carlisle Van Ornum Arsene Christopher Harry Peters Mark Halderman John B. Butler Charles Comerford Niles J. Millen Carol M. Ferrell J. Alfred Aplin James E. Wade Nathan Rogan Henry Shebley S. Ross Hatton Tack Wm. Cook John J. Barry Chester Ramsey Elmer Aldrich Ralph Dale James D. Stokes (78) George D. Seymour Glenn Whitesell A. E. Johnson Gustav E. Geibel Ernest E. McBain Karl Lund Henry A. Hjersman Elden H. Vestal Walter Shannon Jack R. Bell Edwin V. Miller Phil M. Roedel Chester Woodhull W. S. Talbott Richard Bliss William D. Hoskins Edgar Zumwalt Earl Leitritz John M. Spicer Wm. Longhurst Harold Wilberg Leslie Edserton o Arthur L. Gee Laurence Werder Robert McDonald Frank L. D. Felton James A. Reutgen David M. Selleck Chris Wm. Loris James T. Deuel Lionel E. Clement Thomas Borneman Richard Riegelheth Willard Greenwald Carl G. Hill H. S. Vary Emil Dorio Donald Glass Ruth Smith Wm. J. Overton Daniel F. Tillotson Earl S. Herald Theodore Heryford Ellis Berry Lawrence Cloyd Eleanor Larios John Laughlin Ralph Classic Owen Mello Gordon L. Bolander John B. Cowan Harold Erwick Bert Mann Douglas Condie Andrew Weaver Robert Fraser Don Davison William Payne Harlev Groves Herbert Ream Merrill Garrie Heryford Kenneth Doty Don Chipman Howard Twining Fred Ross Robert Macklin Ray Bruer Wm. Stewart David L. Ward filled inline of Burg Bvron Sylvester Arthur Boeke Richard DeLarge Bcleascd From ^cttoe jScruice George E. Booker William Bradford Frank Burns J. William Cook J. Ross Cox A. F. Crocker Henry Frahm Robert N. Hart John Hurley William LaMarr Robert O'Brien C. Lawrence O'Leary Harold Roberts Leo Rossier C. L. Savage Arthur L. Stager George Shocklev (79) PROGRAM OF THE BUREAU OF MARINE FISHERIES ' By Richard Van Cleve Chief, Bureau of Marine Fisheries California Division of Fish and Game TABLE OF CONTENTS Page INTRODUCTION 1 81 CONSERVATION OF CALIFORNIA FISHERIES 82 DISTRIBUTION OF RESEARCH EFFORT 86 STATISTICAL RECORDS 88 SARDINES 90 SALM< >N 101 TUNA 113 MACKEREL IIS SHARK 128 OTHER FISHERY PROP.LEMS 132 SUMMARY 134 LITERATURE CITED — - 137 > T Submitted for publication, April, 1945. The program outlined here comprises the ideas of the entire staff of the Bureau. Special credit is due Dr. Frances N: Clark in charge of the sardine investigations, Mr. J. B. Phillips who is now working on the age analyses of sardines, Mr. D. H. Fry, Jr. who has carried on the mackerel investigations and for the past year has supervised the Central Valleys salmon work, Mr Paul Bonnot who has for some years carried on the .shellfish investigations, Mr. W. E. Ripley in charge of the soupfin shark investiga- tions, and Mr. W. L. Scofield in charge of the statistical system's field work. (.80. ) INTRODUCTION The program of the Bureau of Marine Fisheries is outlined for three reasons. First, the need for stating the general objectives of the research program of this Bureau has long been felt. While parts of the discus- sion of these objectives are necessarily technical, it is hoped that it will give to the fishing industry and sportsmen of this State some idea of the ultimate purposes of this research. The principal lines of investiga- tion are described in some detail with brief summaries of accomplishments to date to illustrate methods used to attain desired results. Second, the future course of these programs is charted in order to make known our plans, the fulfillment of which is felt will result in a sound basis for the conservation of California's marine and commercial fisheries resources. These plans are in no way intended to be inflexible since a fundamental quality of a sound research program is that it must be responsive to changes that may be demanded as it develops. Third, the principal problems that must be tackled are outlined, with some indication of the many species that will have to be included in the investigations to lay a foundation for intelligent exploitation. At present the research program of the Bureau is drastically cur- tailed. Major shifts can therefore be accomplished after the war without dislocation or upset. A general statement of the program is therefore particularly necessary now. Commercial marine fisheries research may be developed along two lines. Technological investigations may be used to improve methods of catching or preserving fish, and to furnish information on distribution to enable fishermen to find them more easily or to extend the range of their operations. Other investigations may be called biological research and are designed to provide for the conservation of the species. The two objectives overlap in some respects, but are different enough to require separate treatment. The function of technological investiga- tions is principally improvement of the industry through improved methods of utilization, and the objectives are obvious. The principal objective of the biological investigations, however, is not always so obvious. It has been defined as ' ' conservation of our marine resources ' ', "wise use", or "maximum use providing for continuous yield". Such definitions are meaningless unless the significance of these catch phrases is appreciated. (SI ) 2 — 45142 82 CALIFORNIA FISH AND GAME The validity of the fundamental concept of obtaining through prop- erly conceived and efficiently executed regulation a larger yield from a marine fishery than can be expected under a condition of unrestricted and over-expanded exploitation has been demonstrated for the north Pacific halibut (Thompson & Bell, 1934). This fishery is the first, and so far the only marine fishery that is entirely under regulation. For this reason the results are of great importance to all marine fisheries. In 1930 intensive fishing by the entire fleet was required to land a catch of forty-nine million pounds of halibut in nine months of opera- tions. The catch per unit of gear from the population of fish inhabiting the coast of southeastern Alaska, British Columbia, and Washington had fallen from 280 pounds in 1907 to 35 pounds in 1930. The catch from the less depleted stocks along the rest of the coast of Alaska to Unimak Pass in the Aleutian Islands had fallen from 288 pounds per unit in 1915 to 64.7 in 1930. The intense fishery on the more depleted stock had practically eliminated the spawning sizes of fish. The evidence of deple- tion was inescapable and by 1931 the fishing fleet was in distress, oper- ating at a loss. By this time a sound biological basis for regulation had been devel- oped. With these combined stimuli, a new treaty was adopted in 1932 which provided for a total catch limit on each of these independent stocks of fish. The benefits were immediate ; and by 1944 the catch per unit of gear had increased to 2.4 times its 1930 level off the coast of British Columbia and southeastern Alaska. More fish are now taken with a fraction of the effort required in 1930 ; and the released energies of the fishermen are available to use profitably in the increased produc- tion of other species. Not all fisheries will lend themselves so admirably to regulation as does the halibut. However, the principles involved hold in all fish popu- lations. That is, within broad limits, each species and each separate population of that species is able to produce fish at a certain rate, depend- ent upon its biological characteristics of growth, mortality, and rate of reproduction. To take more than this amount of fish will result in eco- nomic waste through the eventual decrease of total take, as well as the increased effort and cost of obtaining it. On the other hand, to take less than this amount is also a waste, since the full potentialities of the resource are then not being realized. CONSERVATION OF CALIFORNIA FISHERIES The increasing importance of California's fisheries resources with the increased population of this State not only demands that we make full use of the fisheries, but also that we do not over-use- them. We must adjust the rate of exploitation of each species to the ability of that species to produce. This adjustment is the objective of the second branch of marine fisheries research. Without that research, the adjustment is impossible and our fisheries resources will eventually become depleted. Under such mismanagement, productive fisheries will be lost. The indus- try will be faced with increased costs and eventual dependence on less desirable species or imported products. In either case, the fishermen lose their means of livelihood. The principal product of this branch of marine fisheries research is some form of regulation. Artificial propagation of marine species has PROGRAM OP MARINE FISHERIES 83 been proven impracticable ; and it is conceded that artificial propagation of anadromous species has not been proven more efficient than natural propagation, nor has it been found economically justifiable. There is no possibility of controlling the natural marine environment so as to pro- duce a better yield. The only factor that can be affected is the rate of predation by man. This can be adjusted by regulation. The stream environment of anadromous fishes can be controlled, and in fact along the western seaboard is being controlled in an adverse manner by the construction of dams and diversions that are rapidly clos- ing large sections of our streams to such species, or are drying them up. This problem is particularly important to the salmon fisheries, and will be considered under the salmon program. Because of the importance of well-founded conservation programs to the welfare of commercial, as well as sport fisheries, a discussion of the principles involved is necessary. Reactions of Marine Populations to Their Fisheries In the normal growth of a fishery there are certain developments which may be expected, provided the stock of fish exploited is in balance with its environment, and natural fluctuations are not great enough to mask the effects of the fishery. As noted above, in the halibut the amount of fish taken per unit of gear run, or, in other words, per unit of effort, has been found useful as a measure of the abundance. Using this meas- ure, or any other appropriate one, the catch per unit of effort in any fishery will fall with an increasing intensity of fishing; and if this intensity finally becomes constant over a long period, the catch per unit will level off. The average size of fish taken in any fishery will decrease as the larger and older fish decrease in abundance; but this too should level off at some point if the fishery does not continue to increase in intensity. Normally, too, the fishery may be gradually extended either throughout the range of the species, or, as in the sardine fishery, to the limit of economical operation of the fishing" fleet. Each further extension of the grounds is usually associated with increased efficiency of boats or gear, and signifies an increased intensity. Over a period of time, the extension of fishing range usually reaches a maximum for each change in gear and boats. With the decrease in abundance of larger sizes of fish, the average length of life of a fish before it is caught will be less. The length of time over which dominant age groups can be traced in the fishery will decrease, and the fishery will come to depend more and more on fewer age groups. Changes in number of older fish may also result in changes in num- bers of eggs and young produced. These changes may be unimportant, compared with those resulting from variations in other factors, such as temperature of the water or abundance of the microscopic food at some early critical stage of development. The existence of dominant age groups of sardines, even under the early small fishery of 1920 to 1933 indicates that natural conditions played a large part in determining the size of any one year class. "What factors cause these fluctuations are not known. Until better methods are perfected of determining abundance of the sardine eggs and larvae, or the absolute abundance of separate age groups in the population, and until these improved methods are extended over enough of the range of distribution to give dependable results, it is 84 CALIFORNIA FISH AND GAME impossible to state whether or not changes in abundance of adults result- ing from increased fishing- intensities can or can not influence the abund- ance of the larger age classes through decreased production of eggs. In slow-growing species winch are exploited for several years before reach- ing maturity, it is almost inevitable that the amount of spawn produced will be diminished by an intensive fishery. In species which mature earlier and at or before the time they enter the fishery, it is possible that the effects may not be so marked. However, too much faith must not be placed upon the ability of any stock to produce sufficient eggs and young under a heavy fishery until this capacity has been proven to exist. A decrease in average size of fish with a shorter life expectancy, as well as a lower catch per unit of effort, associated with an increased range of fishing activity, may be merely evidence of the normal growth of a fishery. Thev indicate a decrease in abundance of fish, but this decrease occurs from the moment fishing of any intensity starts. Depletion What, then, is meant by overfishing, or depletion ? Both of these terms may be purely relative in their significance. They denote a reduction in numbers of fish, as a result of fishing, below the point at which the boats can operate economically. A specialized fishery, depending upon one species and not adaptable to taking other species, could die under these conditions, or an inefficient fishing method may suffer from overfishing where a more efficient operation could prosper. As far as we now know, there is little possibility of the bio- logical extinction of most species by a fishery. Exception must be made in the case of the most efficient types of gear, the most valuable or acces- sible species, or those species with slow growth or a low rate of repro- duction. In general, a fishery will kill itself long before it kills the species it depends upon. In one sense, then, overfishing and its copartner depletion may -be thought of as economic in nature, and might be defined as that state of a fishery where the abundance of the species upon which it depends has decreased as a result of fishing beyond the point at which the catch per unit of effort is sufficient to permit the boats to operate at a profit. Many complications arise, and the point at which the balance is tipped one way or the other will vary with the price of fish and the cost of operations. There is another meaning that may be given to over-fishing, which is purely biological. Within the limits of natural fluctuations, every species, or each fishery, will have a certain level at which the efficiency of production in terms of pounds of fish is greatest. This level is deter- mined by the rate of reproduction, the rate of growth, and the rate of natural death, which have characteristic values for each species but may vary within limits for separate races or populations. For any species and any combination of these values there is theoretically a cer- tain range of fishing intensity which may be extended to give the highest return of which that species is capable (Baranov, 1918, Thompson & Bell, 1934). Under these conditions the excess of growth and recruitment over natural losses is entirely utilized in producing the largest annual catch possible without diminishing the brood stock. Overfishing may be thought of as that condition where the fishing intensity has become so great that this excess is thereby diminished. PROGRAM OF MARINE FISHERIES 85 Various features of the relationships between rate of natural death, fishing mortality, growth and catch have been discussed by many authors and developed primarily by Baranov, 1918, and applied by Thompson & Bell, 1934, and Thompson, 1937. From these discussions, it is clear that overfishing may exist in a stabilized fishery, and may vary in degree. It is apparent that the effects of over-fishing usually become of concern to the industry only when its biological effects result in a stock that cannot be economically exploited. This may or may not be at a level of abundance that is dangerous to the continued stability of the stock.2 Fisheries administrators must be concerned with the adjustment of the fishery to obtain the maximum yield. The Function and Methods of Biological Fisheries Research The above factors are fundamental to an understanding of the function of biological fisheries research in the conservation of a fishery. It is assumed that it is desirable to stabilize a fishery at its highest potential yield, and that it is undesirable to permit overfishing with its resultant decrease in rate of returns and the economic hardships thus imposed on the industry. The seemingly abstruse fisheries investiga- tions of conservation agencies can be justified under these assumptions if they can be proven to lead to a solution of the problem of conservation. The general objectives of biological marine fisheries research are: First, to define the stock of fish supporting a particular fishery; and second, to determine the factors affecting the abundance within the stock and to measure their effect. The stock is first defined as to species. Then within each species the distribution and existence of separate races, or more or less inde- pendent groups, is determined, and the movement of individuals within the range of distribution is studied. In other words, we must find out whether the fishery is supported by one population, or by a number of independent groups — each requiring separate treatment, Each independent group must be considered by itself, and the various factors controlling its productivity determined. The rate of reproduction in terms of numbers of eggs or young produced by the average individual and by the entire stock, and the variations in these numbers from season to season, must be related to the intensity of fishing and to associated natural factors. The rate of growth, determin- ing the weight of the individual at any age, must be correlated with the size and age at maturity, and the size and age at which they are taken by the fishery. An estimate of natural mortality is necessary to aid in determining the level of fishing intensity which should be maintained to obtain the greatest yield. All of these factors must be considered in the management of a fishery. While some are more important than others, intelligent regula- tion is impossible without some knowledge of all of them. Without this information, control cannot be planned ; and if exercised, it usually expresses the desires of the strongest pressure groups. As such, it has - For the sake of simplicity, the question of competition between species is omitted, as well as the problem of supplanting a depleted desirable species with a less des.rab.e species through intense fishing. These problems are nevertheless real ones and must be considered. Mi CALIFORNIA FISH AND GAME no foundation in fact, and certainly cannot benefit the fisheries, while in some cases it may be harmful. Fisheries research is, therefore, entirely practical in its objective. Contrary to frequently expressed opinions, its purpose is not to provide work either for indigent biologists or for those misguided people solely interested in delving into abstruse problems that are of concern only to similarly interested individuals. Its justification for support as a public enterprise is to furnish material on which administrators can base an intelligent and progressive conservation program. It is true that results obtained have in the past sometimes not been usable but these have arisen from programs that were not properly designed to relate the work to the industries exploiting the fisheries. In the course of the investigations many fundamental biological problems of only indirect application to administration are encountered and must be tackled. These supplement the main program but should never dominate it. The application of the principles outlined above will become more apparent with the consideration of the problems of the different fisheries. DISTRIBUTION OF RESEARCH EFFORT One of the difficult problems encountered in planning a research program concerned with such a wide variety of species as is the Bureau of Marine Fisheries is the proper distribution of effort. The catch of fish and shellfish in California is recorded under seventy different cate- gories. Many of these, such as "flounder", "sole", "shark", "rock bass", "salmon", etc., comprise several different species. There are approximately 120 different species of fish and shellfish which enter the California commercial catch in some form or other. The problem is to decide what species should be worked on first, and what type of information is needed. This decision rests upon two factors : The commercial importance of the species (its productivity), and the need for information as shown by the course of its landings. Aside from the value of the various species compared with the value of other species in the State 's total catch, there are certain problems that have arisen and will arise in the future which require solution. The cost of their investigation may be all out of propor- tion to the annual value of the fishes concerned. However, if, by a few years' concerted effort, those fishes can be saved for future generations, the money will be well invested. The most noteworthy such case is found in the Central Valleys Irri- gation and Power Development. As originally designed, the many dams proposed throughout the Central Valleys area, combined with the diver- sion ditches, would set up conditions under which even the much-per- secuted Sacramento salmon could not long survive. Whereas a tax income is derived from salmon, amounting to from $15,000 to $30,000 per year, the cost of the investigation required to attempt to allay the adverse features of the project in favor of the salmon will amount to sev- eral times the income derived by the State from this fishery. Another basic operation will be a complete survey of our clam beaches, and kelp and agar beds. Individually, none of these species — mollusk or alga — appear of importance, yet collectively they are defin- itely a factor in our fishing industry. In both these groups the beds are easily subject to heavy exploitation, and need control. PKOGRAM OF MARINE FISHERIES 87 TABLE 1 California Landings and Value of Commercial Fish Landings by California Boats — 1943 Species Pounds Value Sardine 972,249,015 $10,781,440 Mackerel, Pacific 75,262,739 1,492,918 Tuna, Yellowfin 49,261,328 4,880,540 Tuna, Skipjack . 28,893,784 2,582,850 Tuna, Albacore 21,384,864 3,477,417 Mackerel, Horse 12,698,974 235,878 Tuna, Bluefin 10,178,768 967,562 Squid 9,164,361 265,028 Salmon ^ 6,581,076 1,227,624 Yellowtail 4,934,879 368,724 Sole 4,782,379 265.203 Barracuda 3,775,278 656,372 Shark 3,729,246 1,933,173 Sablefish 3,206,074 267,671 Rockfish _„ 1 2,762,192 185,541 Shad 2,348,143 114,648 Crab 2,315,338 353,287 Tuna, Bonito 2,282,299 181,354 Anchovy 1,570,803 29,195 Smelt 1,562,241 198,787 Halibut, California 1,121,673 238,670 Lobster, Spiny 985,525 256,153 Oyster, Japanese 741,105 29,656 Cultus, Pacific 719,318 65,010 Sea-bass, Black 700,855 157,298 Abalone 680,444 54,786 Herring, Pacific 630,358 17,239 Clam, Pismo 611,634 57,911 All others 4,646,255 608,834 Totals 1,229,780,948 $31,950,769 The relative volume of landings of various species with their value to the fishermen are shown in Table I. In order of importance of research projects of this Bureau, the sardine investigations must retain first place, both because of the great importance of the fishery, and because of the extent of its development which has maintained the total yield at an average of 548,000 tons since the 1934-35 season. In spite of a considerably lower yield and value than other species, the salmon and Central Valleys investigations must come next in line of emphasis because of the impending loss of this species, resulting from the appar- ent desire to promote the use of water for every possible purpose except that of the fish. The five species of tuna are ranked next in importance, but their investigation will be delayed no longer than the time when an adequate staff can be set up. The wide fluctuations that have taken place in the mackerel catch indicate a definite instability of supply. We must try to determine what this instability arises from, principally with the idea that if by some chance it should be associated with con- trollable factors such as fishing seasons or amount of catch, then by proper allowance for these factors, the fluctuations could be diminished ; or failing this, some method may be found whereby cyclical changes may be predicted. Other work concerned with the crab, shrimp, other shell- fish, rockfishes and flatfish will be prosecuted as soon as adequately trained biologists can be obtained to carry on. 88 CALIFORNIA FISH AND GAME STATISTICAL RECORDS The basis of fisheries research is a record of the amount of fish taken. A system of collecting detailed information as to catch by species, taken from defined areas, landed in particular ports, by different boats, using various types of gear, with records of the purchaser and price, has been developed by the Bureau of Marine Fisheries over the past twenty-five years. It has compiled the most complete and accurate record available anywhere for a comparable complexity of species. Records of total landings and computed annual values of the prod- ucts are not alone sufficient to justify the expense and effort required to maintain acceptable records. Their principal value is found in the record of fluctuations in abundance of the various species upon which the commercial fisheries depend. Whether one is dealing with kelp, mollusks, or fish, the fluctuations in yield, compared with the effort required to obtain that yield, are in most cases the best measures of the condition of the fishery. To serve this purpose, statistical records must be complete and accurate, as well as current. They must be continually checked against changes in methods of fishing and marketing that might affect them or their accuracy. Such a system cannot operate automatically, nor does it grow spon- taneously. The excellence of the present system of the Bureau of Marine Fisheries is a direct result of the enthusiastic and untiring efforts of the many people who have worked with it. Its future depends upon an equal effort by those presently charged with that responsibility. The statistical system must keep pace with changes in the fisheries. Other- wise, it will suffer the fate of so many similar projects which have slipped gradually into an innocuous routine serving no one but those who profit from the salaries paid to administer it. The statistical system has been described in detail in Fish Bulletin No. 44 of the Division of Fish and Game Fish (Bureau of Commercial Fisheries, 1935). It has depended upon close contact with fishermen, processing plants, and buyers, maintained principally by wardens of the marine patrol. An effective system of maintaining and improving the statistical records of our fisheries must be based upon the cooperation of the indus- try. While the submission of statistical returns on landings is required by law, there is no way of enforcing accuracy except through the help of fishermen and buyers, unless the patrol effort could be greatly increased on both sea and land. This would be both impractical and undesirable. The cooperation of the industry can be neither developed nor retained without continuous contact by trained men. An efficient contact system is fundamental to a sound statistical system, and must be developed and maintained either through the marine patrol force or through statistical field men. Type of Records Needed The basic statistical record, of course, is the amount of fish landed. Various problems arise in this regard. While most of the species caught and sold are well recognized, a continual check is required to be sure that inaccuracies do not enter through the notation of fish under wrong specific names. PROGRAM OF MARINE FISHERIES 89 An even greater problem is found in the relative amounts of fish landed round, cleaned, or dressed. Since all figures are eventually recorded in terms of round weight, corrections must be applied to various species landed after cleaning. Changes have taken place in recent years in the methods of handling salmon, for example ; and considerable quanti- ties are landed cleaned. While some of these errors can be corrected through noting price differences, this is not a good check, partly because of different prices paid for the two species of salmon taken in the catch. Another example of present difficulties is found in the shark fishery where practically all carcasses have in recent years been landed both cleaned and dressed. The livers have often been landed alone, and carcasses discarded. It is frequently impossible to separate these weights; and as a result our records of shark landings are inaccurate. In fact, the error has been estimated to be at least thirty per cent. Since the matter of principal interest to conservation is the amount of fish removed from the fishery, some estimate must be obtained of the amount- of fish caught but not recorded as sold because it is discarded as ''unfit for human consumption". It is impossible to say how large is the present error in our records due to all such factors. While the error is probably not large in most cases, a thorough survey of this problem throughout the State must be undertaken as soon as practicable to lay a foundation for corrections. Location of Catch Another basic record is the exact location of the catch. Statements made by individuals indicate that these localities are often purposely inaccurate, usually because fishermen are reluctant to reveal their choice fishing spots to other fishermen through dealers. Only interviews by the Division's employees can correct this, and will require continuous con- tact with fishermen. Gear and Boat Records License records of boats should give information on type and size of boat, and type of gear run. The gear varies throughout the season and must be continually checked. Observation of the gear used upon a particular boat once or twice a year is not enough, since more frequent changes are often made. Accurate records of the changes are required for the basic analysis of catch, according to gear. Some study will be required to determine how effective our records are in this regard. This can be carried on for certain species in the course of their work by the research staff. Others must be checked in the course of the survey of weight records. When boats are first licensed, they are given a "Fish and Game num- ber". This provides a means of identification for a boat that is free of the frequent changes and duplication of names and changes in Customs House numbers. Even these numbers must be checked frequently and new boats lacking numbers must be noted, as well as lost numbers replaced. The statistical system requires first, a survey of its efficiency, as suggested. In some localities, notably northern California ports, field men working directly with the statistical staff will have to be stationed to maintain liaison with the industry. For the present the collection of records and checking of boats along the coast south of San Francisco 3—45142 90 CALIFORNIA FISH AND GAME must remain in the hands of the marine patrol, with occasional checks by scientific personnel. Handling of Records The original ticket forms filled out by the fish buyers, containing basic information, are collected and brought into or mailed by dealers to four central offices — San Francisco, Monterey, Terminal Island, and San Diego. In the San Diego offices these are checked for dealers' names, boat numbers and names, area of capture, etc. ; and then sent to the cen- tral office at Terminal Island. San Francisco and Monterey offices are provided with facilities for punching the cards used in machine analysis. The punched cards, as well as checked original records, are sent to Termi- nal Island. These records of the catches of individual boats and of the purchases of dealers are by law confidential. They cannot be made avail- able to the public except in the form of summaries " * * * * so as not to disclose the individual record or business of any person • * * *' (Section 1096.5 of the Fish and Game Code). The analysis of these records which cover an average of over a billion pounds of fish each year requires an efficient and stable clerical staff. It is planned to move the main statistical office from Terminal Island to central California. This will relieve difficulties experienced in the past in maintaining a clerical staff in a relatively inaccessible locality, and will leave enough room in the present Terminal Island laboratory to accommodate the research staffs needed for the investigation of the tuna, mackerel, and other predominantly southern forms. On the other hand, the locality to which the statistical center is moved must be suitable for the location of some of the research staff ; and in view of this, the places open are very limited. Consideration of the many factors involved points to a choice between Palo Alto and Berkeley. The latter location appears to be most advantageous from the point of view of both the research and statistical staffs, and would have many advantages from the point of view of administration. SARDINES The sardine investigations have been carried on since the establish- ment in 1917 of a scientific staff in this Bureau. Much data have been collected ; but some controversy has developed in the past as to the inter- pretation of the results. It seems to be worthwhile, therefore, to con- sider evidence that has been interpreted as proving depletion, and to examine it in the light of the present condition of the fishery. Catch Per Unit of Effort Investigations of the sardine fishery have shown that a decrease in catch per unit of effort has occurred since the 1935-1936 season. This decrease, as measured by the average catch per boat month has been calculated by Dr. F. N. Clark to be 34 per cent in the last 10 years. The average return per unit of effort, expressed as adjusted weekly catch per boat (Silliman and Clark ms), is shown in figure 21-A as per cent of the 1932-33 average. Another measure of the same thing was calculated by taking the total monthly catch in California in the different years and dividing it by the number of boats fishing. It is interesting to note that this rough figure (shown in figure 21-B) is not very different on PROGRAM OP MARINE FISHERIES 91 the percentage scale from the highly refined and corrected one calcu- lated on a weekly basis. This is hardly surprising since the corrections imposed on the latter measure are based upon correlations which are true only on the average, and in which many complicating and unmeas- ured factors creep in. Corrections for these factors are only valid within the limits of the accuracy of agreement between the variables concerned, and when the trend line is used for this correction all the other possible degrees of relationship expressed in the variation of the individual observed values about the average or trend line are lost. Many other fac- tors not measured by these corrections probably influence the magnitude of this measure of abundance. £00 150 100 a. i 1 1 r T T "l r SARDINES RETURN PER UNIT OF EFFORT ALL CALIFORNIA EXPRESSED AS PERCENTAGE OF 1932-33 I •t o T I "T ~i 1 r SARDINES TOTAL CATCH COMPARED WITH .+.?0Ar EFFORT EXPENDED RETURN PER EFFORT TOTAL EFFORT TOTAL CATCH .— TOTAL BOATS 2000 o t I Fig. 21. California sardines. Return per unit of effort, and total catch compared with effort expended. 92 CALIFORNIA FISH AND GAME Of greatest interest is the fact that both measures show a definite tendency to level off at an average of about 70 per cent of the 1932-33 figure up to the 1940-41 season. In the past two seasons the trend is upward; and in the 1942-43 season it reached a level above that of 1932-33. In figure 21-B, the catch in tons per boat per month in California is compared with the total number of boats fishing, total catch, and total effort, as measured by the total number of boat months, for each year. Theoretically, these various factors should be related in such a manner that a significant increase in number of boats or total effort from a lower to a higher level should be followed by an immediate increase in total catch. At the same time the catch per unit of effort should begin fall- ing. After the initial increase in total catch, it too should change to some new level (as long as the effort remains constant), either higher or lower than before, depending upon whether the fishing has or has not reached its highest productive level. The sardine picture is complicated by many factors. Previous reports (Clark, 1931) have shown that in someyears for unknown reasons there is a greater survival of eggs and young and this results in the pro- duction of a large year class. Entrance of such a year class into the fishery when it has been preceded and is followed by several small year classes will result in a sudden increase in abundance of sardines with a subsequent decline until another large year class appears in the catch. A variation in abundance could be expected, therefore, from the appear- ance and gradual attrition of these large year classes, regardless of the reactions to variations of intensity of fishing. Superimposed upon the effects of variations in size of the population of sardines is that of its availability to the fishermen. This may be determined by the size of schools that are formed, by the courses they follow in their migrations that bring them within the fishing areas or keep them offshore, and by the depths at which they occur or the speed with which they move through the fishing area. All of these may be the result of variations in the ocean currents off the coast, as well as of the location and abundance of food. In addition, prolonged periods of stormy weather or stormy negotiations over fish prices and sales practices have often held the fleets in port for weeks at a time. In spite of all of these complicating factors and the rough, uncor- rected measure of average catch per boat used, some agreement between the actual and theoretical picture is seen in figure 1-B. The effort (boat- months) and number of boats increased continuously from 1932-33 to 1937-38. The total catch kept pace with this increase until the season of 1936-37 when it reached the peak of 725,000 tons. The catch per unit (or catch per boat-month) increased up to a maximum in the 1934-35 season, thereafter falling steadily to 1937-38. Since the 1937-38 season, the number of boats has fallen off from over 379 to about 206 in 1943-44 ; and the number of boat-months has decreased from 1,700 to 1,059 in the same period. Much of this decrease has resulted from the loss of boats to the armed forces which began early in 1941. As a result, the sardine fishery has suffered an artificial reduction in total fishing effort in the last three seasons. PROGRAM OF MARINE FISHERIES 93 IfXtf '*f Fig. 22. The San Pedro fishing fleet. The larger boats are sardine purse seiners. The smaller boats fish with long line, with gill net for shore and bottom fishes, or with trolling gear for albacore. The total catch has tended to vary around an average of slightly over 500,000 tons since the 1937-38 season. The catch per boat-month which hit a low point in 1937-38 remained fairly constant over the next three seasons, then showed a slight rise in 1941-42 and 1942-43. It is too early as yet to state whether or not this rise in catch per unit of effort has resulted from the decrease in total effort and therefore indicates an immediate positive reaction to such changes in the fishery. However, it would not be unreasonable to suppose that this might be true if the reactions of the sardine fishery are the same as those found in the halibut fishery (Thompson & Bell, 1934). On the other hand, this effect may have resulted from the enforced removal of catch limits or from the addition of the month of October to the southern California fishing season in 1941. While the number of boats and boat-months have fallen steadily since 1937, the efficiency of the fleet has increased with the greater skill of fishermen in handling the gear, the use of radios in concentrating greater numbers of boats in areas of heavier abundance of fish, and with improve- ments in gear and boats. The true amount of effort may have remained at least at the same level as in 1937 until the great loss of boats occurred in the 1941-42 season. With a multitude of complicating factors, more accurate measures of abundance of sardines and of the total effort expended by the fleet are both needed. However, if the present figures can be accepted as suf- ficiently accurate to indicate trends, some conclusions can be tentatively drawn. All such conclusions must be qualified, however, by the lack of definite knowledge upon many points of the biology of the sardine popu- lation such as : the variations in distribution and total success of spawning 94 CALIFORNIA FISH AND GAME and the relation between such variations and the size of the resulting year class; the quantitative relationships between different sections of the population that extend from Mexico to Canada ; the varying move- ments of this population that determine its availability to fishermen regardless of its actual size ; as well as the effects upon catch per unit of effort of a large year class. With these and other reservations in mind, the relationships indi- cated in figure 21-B may be interpreted literally as indicating that the abundance of sardines and resultant total production is affected by the 240 230 220- 210 200 240 230 200 190 ieo 230 220 210 200 190 ISO SAN FRANCISCO H I I 1 1 I I 1 I 1 h J"*7i *« 's«, V*y MONTEREY ~— ±z i — i — i — y -{ I I 1 r ♦ * * * o * 01 0> • - 93 II. I 10.7 10.2 9.7 88 - I I.I 10.7 102 «. 111 X u 97 5 x 9.3 t 88 83 10.7 10.2 9.7 9.3 88 8.3 Fig. 23. Average length of sardines PROGRAM OF MARINE FISHERIES 95 amount of fishing effort expended. They may also indicate that a fur- ther increase in total fishing effort, much beyond that which held on the average during the period following 1937-38, will not result in a great permanent increase in total catch. Moreover, the average return per boat may be expected to fall as the number of boats increases. A fur- ther decrease in total catch may occur if the total fishing effort is increased markedly bej^ond the 1937-38 level. Confirmation of these relationships will require at least a partial solution of the problems out- lined above. Public and industrial inertia will probably permit a further series of changes in the fishery to occur before action is demanded or becomes possible whether the result is favorable or unfavorable to the fishery. Average Size Clark, 1939, noted a steady decrease in the average sizes of fish taken at the three ports in the fall and winter fisheries. Extended to the 1943- 44 season, the average size shows practically the same trend as the catch per unit of effort, although the decrease started in 1932, at the same time the intensity of fishing began to increase. Average sizes of fish, obtained from samples of the catch at the three ports, are shown in figure 23 for the fall and winter fisheries. These fish- eries were divided on the basis used by F. N. Clark (1939). San Pedro shows a leveling off of the average sizes since 1938-39, indicating that the total fishing intensity, the growth, recruitment, and natural mortality are very nearly in balance. The increase in average size for both fall Fig. 24. Unloading a "deckload" load of sardines (1933). 96 CALIFORNIA FISH AND GAME and winter fish off San Francisco and Monterey is difficult to explain at present, but may be due to variations in relative abundance of small fish due to changes in size of dominant year classes. The San Francisco fishery shows several differences in results of tagging experiments that point toward the validity of this explanation. (Clark & Janssen ms.) Clark also demonstrated that the dominant age classes which for- merly could be followed and noted in the fishery for eight to ten years now retain their dominant positions for from two to four years only. All of these measures of population condition indicate a decrease in abundance over that which existed prior to the great growth of the fish- ery, beginning in the 1934-35 season. At least they indicate a decrease in abundance of the sizes of fish that support the fishery. However, it appears that some sort of stability was reached by 1938-39, and is being maintained under present levels of fishing intensity. Recruitment Silliman (1943) published a theoretical treatment of the rates of disappearance of the various age groups at present intensities, compared with those noted for the period of 1919-20 to 1932-33. Combining these with total catch and relative amounts of effort, he found an increase of two-and-one-third times in the rate of recruitment under the more intense fishery than under the former less intense one. The possibility that this increase in rate of recruitment resulted from a natural cycle in environ- mental conditions which resulted in a heavier spawning and greater sur- vival of young in the latter period, as well as the nature of the date and method of analysis used, make it necessary to accept this conclusion with some reservations. Results of last year's sampling give further indica- tion that this increased recruitment was not a result of the decreased abundance, and was due to one or two dominant year classes that were produced in this period. It cannot be interpreted at present as proving a direct relationship between intensity of fishing and rate of recruitment. The important features of the reactions of the sardine to its fishery will be found in the continued course of the above-noted measures of abundance. The average catch per unit of effort, as measured above, the average size of fish, and associated length of life of the dominant year classes apparently have reached a level under present fishing intensity and have shown a tendency to rise with a decreased intensity of fishing. It now remains to be seen if natural fluctuations in abundance will be great enough to upset periodically this balance, and either bring about a major decrease or increase in abundance with its associated repercussions on the industry. Even though such a level may have been reached, a further increase of intensity of fishing should cause another fall in abundance. Where should the abundance be adjusted, presuming such a course of action should be found necessary? There is a possibility that the economics of the fishery may cause it to adjust itself finally to reach its own level of intensity ; but if this does not occur, and the average size of fish, and average rate of return should again begin their downward trend with increased fishing, how far should they be permitted to go? Present knowledge of the sardine and its fishery is not sufficient to permit setting such a figure. Much will depend upon the results obtained by fishermen in the next few years. If the total catch falls markedly PROGRAM OF MARINE FISHERIES 97 with an increased fishing intensity, regulations should be adopted to curtail the catch. However, it cannot yet be predicted whether or not this will happen. Until the expected increase of intensity has occurred and the reaction is noted, no further recommendation can be made. Present Program The present sardine program of the Bureau of Marine Fisheries is greatly restricted because of lack of personnel. It has been carried out in cooperation with fisheries departments of Washington, Oregon, the Fisheries Research Board of Canada, and the U. S. Fish and Wildlife Service. Current work consists of maintaining and working up the samples of fish collected from fishing boats ; and of determining the ages of the fish in these samples and therefrom obtaining information as to the relative strength of various year classes and the rate at which they disappear from the fishery. As shown by Sette (1943), Walford and Mosher (1943), and others, the use of these samples requires a complex series of manipulations to correct for various factors, all of which tend to produce errors in the results. These errors distort the picture that would be presented were the stocks completely available to the fishery, and no factors other than natural mortality and fishing mortality, growth and recruitment, measured. The availability of the fish, and the unmeas- ured but hypothesized effects of weather and other influences upon the efficiency of the fleet in producing fish make it very difficult to determine the accuracy of the results obtained. It is obvious that the more simple and direct the approach to this problem can be made, the more quickly will usable and understandable results be obtained. The primary objective is to determine the nature of the stock that supports the sardine fishery. This has been attacked by tagging — the simplest and most direct approach possible. The number of fish tagged by the participating organizations is shown in Table 2, with the number of tags returned from the fishery up to the end of 1943. tabCe 2 Numbers of Sardines Tagged by Different Agencies to Date and Numbers of Tags Returned Fisheries No. of No. of department fish fish tagging tagged recaptured California 108,333 7,591 Fisheries Research Board of Canada 20,391 485 Oregon 7,788 70 Tagging methods, and methods of obtaining recaptured tags are described by Clark & Janssen ms. and by Hart (1943). The distribu- tions of the returns indicate that fish migrate throughout the range of the fishery from southern California to British Columbia. When corrected for the different numbers of fish taken by the fishery at different parts of the coast, the rate of decline in abundance calculated for the entire coast is about 61 per cent. When the returns obtained in the California fish- ery from California tagging experiments are used for calculating rates of decline, higher rates are obtained than when returns from the north- west fishery are included. The differences are probably a measure of the 4—45142 98 CALIFORNIA FISH AND GAME loss of fish from California waters due to migration of the fish to the northward. The many complexities introduced by the combination of many experiments carried out in different years and therefore subject to as many different sections of the varying trend in fishing intensity, as well as to different sections of the ecological trend, render it difficult to interpret these results. Complexities occur in the distribution of the fish. However, these are of minor importance to the main thesis that the sardine fisheries of British Columbia, Washington, Oregon, and Cali- fornia seem to be based upon the same stock. Future Program The results of the investigations to date define the program for the future. It is not desirable to set up exact rules or methods under which this program should be carried out, but merely to point out various objectives which at present appear to be most important and to require the most effort. While the work outlined here is essentially that con- templated for the staff of the Bureau of Marine Fisheries, it will have to be carried out with the assistance of other cooperating agencies. Objectives Changes that have taken place in sardine abundance, as indicated by the various measures of catch per unit of effort, and the changes that have occurred in the intensity of fishing, and total catch, shown by the previous investigation of the biology of the species, require that the program must be pursued along several lines. The California Division of Fish and Game, having as its duty the conservation of the species, as well as the "economical utilization" of the fish resources of the State (Sections 31 and 1068 of the Fish and Game Code), must continue to follow the relation of catch per unit of effort to total effort, total catch and the related reactions of the species itself to variations in those factors. Future changes in fishing intensity must be closely watched, along with the reaction of the sardine 'population to these, changes. The variations in average size of fish, average catch per unit of effort, total catch, life expectancy of dominant age groups, as well as frequency of occurrence of these dominant age groups and the consistency of their occurrence will all determine whether or not regulation is required. They will also indicate the type of regulation that may have to be im- posed. Fluctuations in total catch must be studied to determine their causes, if possible ; and eventually some basis for predicting the course of future abundance (or production) must be established. Measure of Fishing Effort At present the measures of fishing effort are unsatisfactory, if not non-existent. The use of the catch per boat per week, or catch per boat per month as the catch per unit of effort appears to leave too many factors of unknown importance unmeasured. Even with the applica- tion of corrections for various independent variables such as weather, stage of the moon, etc., as was seen above for the catch per boat- week, the corrections still do not change the trend shown by the rough catch PROGRAM OF MARINE FISHERIES 99 per boat per month. Obviously, this gap must be filled. This may be accomplished, either by interviewing a significant number of boats each day as to the previous night's activities, or by the establishment of a system of boat logs. The latter will require a system of daily inter- views anyway until it can be well established and can never be expected to work well without frequent interviews and copying of these logs at each port. The feasibility of such logs must be investigated, and tried out at the earliest possible moment. Another source of information will be found in sending out trained observers with the boats to gather notes as to fishing practices. This work should precede the establishment of logs in order that the informa- tion to be requested may be of the right kind. It will also make it possible to set up a system of logs that will be most effective, and will be the least possible burden to the boat captain. Fig. 25. Sardine purse seiner hauling- its net. The net is hauled by taking a bite with the line from the end of the boom. The crew merely stacks the heavy net. Samples of the Catch The cooperative study of catch samples may be continued with age analyses to determine the strength of various age groups in the fishery. Measurements of changes in average size, of fish, also obtained from these samples, constitute a measure of the reactions of the stock to the changes in the fishery. However, the amount of benefit derived from these observations over the past 24 years has not been in proportion to the effort involved. This activity may have to be curtailed until basic information on important phases of the biology of the species has been gathered and analyzed. ]00 CALIFORNIA FISH AND GAME Tagging Results of work now in progress give a measure of the rates of mor- tality now operating on the sardine stock. They indicate a need for further tagging to check these values, and to provide a basis for study- ing the effects of migrations on the rates of decline. Returns from the last tagging experiments are still coming in. Further tagging is required to clear up some features both of mor- tality rates and of various features of distribution and migration. It must be undertaken on an intensive scale by the Bureau of Marine Fish- eries in cooperation with those agencies that have shown their interest in this investigation. The program of actual tagging might be com- pleted in two, or three years, but may require more time and should result in two things: a uniform distribution of large numbers of tags along the entire coast from Mexico to British Columbia; and at least one intensive concentration of a large number of tags (about 100,000) in one selected area to be released throughout one fishing season. Repetition of this type of experiment may be necessary. Three to four boats operating simultaneously along the coast throughout the year either on fish purchased from fishermen or caught by the tagging boats should fill the requirements. Egg and Larval Work Quantitative sampling of the eggs and larvae, as now carried out by the U. S. Fish and Wildlife Service, is confined to the area south of Point Conception. A survey should be conducted along the entire coast from Lower California north to British Columbia, which would cover enough of the year to be sure that previous surveys which indicated a lack of spawning in the northern- region were not made at the wrong time of year or in the wrong season. A cooperative program of such sampling should be instituted to extend the region of observation to determine definitely whether significant results can be obtained by sampling the southern area only. The results of such work, combined with hydrographic and plankton studies, will apply to the determina- tion of causes of fluctuations in the size of dominant year classes, and eventually assist in predictions of abundance. Young Fish — Bait Fishery The live bait fishery supplying both sport and commercial fisher- men in southern California takes an unknown quantity of young sar- dines each year. A system of obtaining usable records from this fishery was being established when work was stopped by the loss of the man in charge to the Navy. This work must be taken up again as soon as possible, and extended to determine the relation of this fishery to the abundance of young sardines. In general, the work must be aimed at quickly developing the sim- plest yet most accurate method of observing the sardine fishery that will indicate the changes that occur in the abundance of the species with changes in the fishery. Regulations should not be imposed until required. It is probable that the most practical method that can be devised will be the limitation of total catch. Such a limit will have to be pro-rated among the various sections of the coast on some basis to be agreed upon between the various states and the Province of Brit- ish Columbia. PROGRAM OP MARINE FISHERIES 101 SALMON In the early development of California, few people must have con- sidered the effects of placer mining and dredging for gold upon the fish which used the streams for spawning. The resultant destruction of salmon must have been great. Later the development of power and irrigation projects as well as of debris dams continued a heedless destruc- tion of this species through elimination of spawning areas and killing of both adults and young in dry streams and in irrigation and power ditches. Estimates made of the amount of salmon spawning area lost in the central Valleys vary from 50 per cent to 75 per cent of the original total. However, these have been based at best upon imperfect knowledge of what the salmon consider usable stream bed. There is little doubt, however, that 75 per cent would probably be the closest estimate. The attrition of spawning areas has been so gradual that no one thought of its eventual effects in spite of the fact that a prosperous salmon fishery was built up during the latter part of the nineteenth century and the first 20 years of this one. Ignorance of many basic phases of the salmon life history, as well as a blythe disregard for conservation until recent times, contributed to this negligence. With some appreciation of the fundamentals of conservation as well as of the biology of the salmon has suddenly come the realization that in the Central Valleys area this species has reached the limit of its endurance in loss of spawning areas and loss of fish through inadequate protection of both adult and immature migrants. This realization has been crystal- lized by the grandiose scheme now in progress of formulation and execu- tion by various federal agencies for complete utilization of all water in this area. The salmon investigations in California are determined for the immediate future largely by these water development programs for electric power generation, irrigation, and flood control. With large dams, impassable to salmon, planned for practically every major stream in the area in which salmon occur, and with smaller diversion dams below them, the future of salmon in California will depend upon whether or not these artificial hazards can be adapted to the requirements of the fish. Gravelly stream beds must be accessible to adult salmon that move in from the sea to spawn. These areas must be covered with flowing water of suitable temperature, and free from silt, for the development of the young during three or four months following spawning in the fall of the year. Thereafter, the young salmon must be able to move down- stream again to the sea in order to complete their life cycle. Two species of salmon occur in California in significant numbers — the Silver salmon (Oncorhynchus kisutch) and the King, Chinook, or Tyee salmon (Oncorhynchus tschawytscha). The former is found princi- pally in the small coastal streams where major water development has not yet been extended. The latter inhabit the larger streams, and form the major portion of the sportsmen's salmon catch, as well as the com- mercial fishermen's. This species is the one principally affected by the extensive hydro-electric, irrigation, and flood control projects now built or planned for postwar construction. This species is of principal concern for this reason, but the Silvers must also be included in the program inasmuch as they furnish a significant portion of the commercial and 102 CALIFORNIA FISH AND GAME sport catch, and will be affected eventually by the water "conservation development" of coastal streams. TABLE 3 Total Landings in Pounds of King and Silver Salmon in California 1939-1943 Year Unclassified King Silver Total 1939 2,142,579 634,282 9,532 2,786,393 1940 3,413,971 2,448,483 809,934 6,672,388 1941 16,523 3,157,070 614,163 3,787,756 1942 9,601 6,215,157 301,935 6,526,693 1943 1,674,180 4,562,322 331,263 6,567,765 The salmon life history, combined with its relationship to the water development programs, divides the investigation into two phases. One aspect involves the protection of salmon and other anadromous species from the results of damming the streams in which they spawn or through which they pass on the way to or from the spawning grounds. It includes provision of fish ladders where necessary and desirable for the adults, and screens in water diversions to protect the young during their down- stream migration. Also involved is the planning storage capacity and flow schedules of the various dams to provide adequate water for the fish below them, and where possible the location of dams where adequate water conservation can be combined with the preservation of sufficient spawning area to preserve at least part of the runs. The other phase of the investigation is concerned with the conser- vation of the species in the sense that it involves the study of the biology and distribution of the species, and the relation of the various races of fish to the commercial and sport fisheries. The object of this phase of investigation is the adaptation of its regulation to the requirements of maintaining the species. The existence and definition of separate races, and the methods of distributing the burden of fishing over the different groups, must be determined so as to obtain an adequate spawning escape- ment of each one, protecting those that need building up. A study of methods of fitting the dam construction programs to the salmon requirements is being carried out with the cooperation of the U. S. Fish and Wildlife Service. This organization is already operating the salmon salvage work at Shasta Dam on the Sacramento River ; and is laying a foundation for the formulation of protective measures for anadromous fishes on the upper Trinity River where several dams are planned near Fairview, and on the Sacramento River below Shasta to the Table Mountain damsite. The California Division of Fish and Game is carrying on the work in the lower Sacramento Valley and in the San Joaquin Valley where it is hoped that the various structures planned will be able to provide water and spawning gravel for the runs so that salvage will not be required. The Central Valleys Project The principal agencies now planning major water projects in Cali- fornia are the U. S. Army Engineers and the U. S. Bureau of Reclamation. Locations of the dams planned for future construction by these agencies are shown in Figure 13 of " A preliminary report on the fishery resources of California in relation to the Central Valley Project (Van Cleve, PROGRAM OF MARINE FISHERIES 103 1945) with the locations of those dams already completed which block salmon runs. The spawning areas remaining below the proposed and completed dams are also indicated. In the Central Valleys area every salmon spawning stream has been or will be affected by these structures. With the exception of the dam planned for the Table Mountain site on the Sacramento River, however, none of them will eliminate all of the spawning grounds in the streams on which they are located. Moreover, in all cases except the above, and the Tuolumne River where the present run uses the available beds to fullest capacity, the spawning areas left will have a capacity for more than the present runs using them, provided adequate flows are main- tained ; and also provided that the water released below the dams is cool enough for survival of spring and early fall-run fish. Therefore, if these dams are planned to furnisli enough water, to maintain flows over the right periods of the year, there should be no need for such a salvage program as has been provided at Shasta Dam. Detailed study of each project will be required, however, to determine what will be necessary. All provisions of flows will be ineffective unless the Cross Delta Channel planned by the U. S. Bureau of Reclamation is constructed so as to provide free and natural access of all fish to their native streams (see Van Cleve, 1945). Spawning Ground Surveys In planning for the salmon in the Central Valleys area, it is neces- sary to presume that all major dams now planned will be constructed. From this starting point, the factors affecting the areas below them must be studied to determine their availability to salmon, as well as their capacity in terms of spawning fish. Surveys of most of the streams have been made in the past, but with information that has been obtained more recently on the type of gravel and stream conditions considered by the salmon to be suitable for spawning, a re-inspection of practically all of them has been necessary. If possible, the capacity of the different streams at different flow levels must be determined to ascertain what volume of water is needed, and the total quantity that must be provided for the fish. Both spring and fall salmon are found in many of the streams. The spring runs enter the Central Valleys area, on the average, in May. They reach their height in June, then taper off through July into the fall run which appears in August. These late runs reach their great- est volume in October or November, tapering off into December. Some streams lack a spring run, while the fall run is practically non-existent in others. Apparently their varying strengths have been determined by the way the water in these streams has been utilized by irrigation and power dams that have been in existence for many years, rather than by the varying intensity of the fishery. For example, a spring run of approximately ten thousand fish migrates up the San Joaquin River each year, and has held over the summer months below Friant Dam since it blocked the river in 1942. Few fall fish reach this area since the river is usually dried up by irrigation diversions at the so-called "sack dam" near Dos Palos. A few late fall fish still come upstream but these cannot pass this dry area until after the fall freshets which wash the ' ' sack dam ' ' out. It is not surprising therefore to find indications of the preservation of a late fall, or what might better be termed a winter run in this stream. 1(11 CALIFORNIA FISH AND GAME The spring- run fish have survived because they were able to move upstream before the river was dried up. They formerly spent the summer in the cool head waters of the San Joaquin where melting snow water main- tained temperatures low enough for their survival. They have been held successfully below Priant Dam because the water flowing out of this reservoir also maintains low enough temperatures throughout the summer. Surveys of these streams must not only show the area of "suitable" gravel they contain, but also the extent of gravel areas that are covered with water of suitable characteristics for spawning. Moreover, the most suitable gravel is useless unless the fish have access to it. Therefore, all existing clams and weirs below these spawning areas must be examined to determine whether fish ladders must be installed or replaced. The principal hazards to upstream migrants which require imme- diate correction are listed in Table 4 with remedial measures that are recommended. Many other blocks exist. In fact, upon study of the salmon runs in the Central Valleys area and the difficulties that have been placed in the way of their survival, it seems remarkable that any of them have survived. Fig. 26. Enterprise Dam, South Fork of the Feather River. One example of a complete obstruction to the upstream migration of salmon. In some areas considerable numbers of adult salmon are lost in the irrigation ditches. Even though such fish may succeed in spawning in the canals, the young are lost in the fields if the eggs develop to hatch- ing. The fish enter the canals in many ways. In some cases, canals that PROGRAM OF MARINE FISHERIES 105 might not need a screen for the protection of downstream migrants will require a rack to prevent adults from dropping down into them. Drain- age canals or overflow spills also provide easy access to many of these channels, and apparently are important factors in diverting many salmon from the regular migration routes. Regardless of whether the home- stream tendency of the salmon is not so invariably effective as is main- tained by some enthusiasts, or the salmon in the Central Valleys area are adapted to the highly variable and sometimes unfavorable conditions of the southernmost range of the species, the fact remains that the Chinooks of this region seem to enter almost any stream that is available to them, even though they do tend to return apparently to the same general area from which they came. Of course, confusion may arise from the mixture of waters in the irrigation canals, and the spilling of it at random wherever it is convenient. TABLE 4 Principal Hazards to Adult Salmon in Central Valleys Requiring Immediate Correction Stream Hazard Correction Required Sacramento Anderson-Cottonwood Eliminate fish traps behind uprights. Dam Install bar screen above tunnel. Glenn-Colusa Ditch Screen entrance and drainages. Mill Creek Clough Dam Install new ladder on N. end. Los Molinos Dam Install new ladder on S. end. Deer Creek Stanford-Vina Dam Install new ladder on S. end. Butte Creek 15 dams and mouth of Install ladders, regulate flow. creek Screen ditches and spills to upstream migrants. Feather Sutter-Butte Dam Install new ladder on W. end. Repair or replace east ladder. Sutter-Butte and Great Screen upper ends against adults (see Western Canals table 5). Yuba Daguerre Pt. Dam Install new ladder in center. Mokelumne Woodbridge Dam Repair apron to eliminate fish traps. Install new ladder. Tuolumne Modesto Dam Install new ladder in center of stream. Pollution at Modesto Eliminate. Stanislaus Pollution at Escalon Eliminate. Goodwin Dam Eliminate pool trap below dam. Re- duce fluctuations in water flow. Merced Various gravel dams Replace with collapsible dams or install ladders. Adjust flows, screen spills. San Joaquin Sack dam Construct permanent apron with col- lapsible ladder and flow. Clear chan- nel below dam. Mendota Dam Install new ladder at E. end. Salt Slough and blind leads Screen all spills and blind leads. Protection of Downstream Migrants Protection of downstream migrants covers a number of difficult prob- lems that may take years to solve completely. The time at which the young move downstream must be weighed against the operating period of the various canals as an aid to determine the need for screens. The size of the migrating fish must also be determined. Salmon fry have been taken at Hood on the main Sacramento River below the town of Sacra- mento between mid-December and mid-June during 1939, 1940, and 1941. Their lengths averaged from 31.5mm. (1| inches) in December to over 5—45142 106 CALIFORNIA FISH AND GAME SO nun. ' '■'<}, inches) in .June. Other samples obtained at Mossdale on the lower San Joaquin River during the months of January through June of the same years were similar in size. Moreover, samples taken at Mar- tinez in Carquinez Straits in 1939 and 1940 averaged as small as 34.93 mm. (If inches) during February and March (Hatton and Clark, 1942) . It is evident from these figures that losses of young will hinge upon the period of operation of the ditch. Those ditches operated during the migrating period must be tested by fyke nets for actual losses ; and where screens are required, they must be designed to protect the size of migrants involved. Fyke nets, now being used almost exclusively to study these problems, are not entirely satisfactory. The fine-meshed nets do capture such migrating smaller sizes, but unless they are fished in turbulent, rapid- flowing water, the fish soon become large enough to escape the nets. Moreover, the one-quarter inch mesh used normally will allow the escape of unknown numbers of the smallest migrants through the meshes, especi- ally when being hauled. This factor has probably caused a considerable error m determining the relative numbers of fish migrating at different sizes. Reports of large numbers of young salmon of 90 mm. length, and larger in some streams, indicate that possibly more than the previously accepted 10% of the young remain in the rivers until they reach this size, but suffer a disproportionate mortality because of inadequate pro- tection. It may be assumed that the routes of downstream migration will follow the main streams. However, the complexity of sloughs and ditches, especially in the San Joaquin Valley, will require study before a protection program can be based upon any particular series of channels. Screen Program Protection of downstream migrants is for the most part a matter of screening the ditches in which the young salmon are lost. A list of most important hazards to downstream migrants is given in Table 5. Projects listed are but a part of the whole program that must be undertaken eventually but they are the most important ones that require immediate attention. In those cases where actual losses have been proven, immedi- ate remedial measures must be undertaken. It is regrettable that as yet no screen has been devised that is com- pletely satisfactory under all conditions. The size of mesh on all bar screen and wTire barrel screens now installed in the Central Valleys area is too large to stop smaller salmon migrants, or for that matter, the young of any migratory species. On the other hand, substitution of a finer mesh will require expensive installations of much larger size to provide ade- quate flows in the ditches. The need for the finer mesh will depend upon the relation of the period of operations of each ditch to that of the down- stream migration of young and to the actual losses of young salmon in each ditch. The latter can be determined by fyke netting. The possi- bility of using the electric fish screen or some modification of it is being investigated. It may also be possible to develop new and more efficient types of mechanical screens. Of major importance in any fish screen installation is some provision for taking fish away from the front of the screen and back into the stream from which they are diverted. By-passes are lacking on most screens now PROGRAM OF MARINE FISHERIES 107 installed, even though there is no possibility of the small fish swimming back up the ditch against a heavy flow of water, or in some cases back against a head of four to five feet of water where the screen is installed below the control gates. Even if small salmon possessed sufficient intel- ligence to return upstream to seek healthier channels, they could not do so under such circumstances. TABLE 5 Principal Hazards to Downstream Salmon Migrants in Central Valleys Requiring Immediate Correction Stream Hazard Work required Sacramento A.C.I.D. Ditch Screen against 35 mm. fish below tunnel. Glenn-Colusa Screen against 35 mm. fish above pumps. Bypass to main river. Mill Creek Los Molinos Ditch Add correct bypass. Test for loss of migrants. Clough Ditch Test for screen and install bypass. Deer Creek Deer Creek Irr. Co. Dam_Install bypass and fine mesh screen. Stanford-Vina Ditch Install fine mesh screens, and correct bypasses in both N. and S. ditches. Butte Creek 15 dams and various Study all diversions for loss of young diversions and type of screens required. Feather Test Sutter, Butte and Western Canals for loss of young. Yuba Test Hallwood I. D. (Daguerre Point Dam) for loss of young Mokelumne Test Woodbridge I. D. Canal for loss of young. Tuolumne Possibly reduce fluctuation of water level. Merced Test ditches and screen those requir- ing it. San Joaquin Screen all canal take-offs where water diversions begin before end of migra- tion. The size of the job involved in screening all Central Valleys diver- sions may be appreciated from the list given by Hatton (1940, Appendix C) of number and size of pumps taking off from the Sacramento and San Joaquin Rivers and their tributaries. A total of 1,497 of these diversions, varying in size from 2" to 48" in diameter, are listed for the two river systems. Salmon Conservation The basic ideal in the second phase of salmon investigations would be to distribute both the sport and the commercial fisheries in such a manner that their burden would fall upon the various races or stocks of salmon in proportion to the ability of that stock to produce. This, of course, would require a determination of the existence, distribution and size of different races at various stages of the life history and would depend upon the maintenance of the identity of these races in the region of the fishery. This is very unlikely. It undoubtedly would be impos- sible to separate the salmon taken in the outside fishery into those that spawn in the different streams in the Central Valleys area, or in any similar stream area. However, if the stocks which reproduce in the various streams migrate through the inshore and river fishing areas 108 CALIFORNIA FISH AND GAME during certain fairly well-defined periods, it might be possible to dis- tribute the river fishery and possibly the inshore troll fisheries, especially off San Francisco Bay, accordingly. The irregularity of the runs in the rivers in different years would make it impossible to set up an inflexible system to distribute properly the fishing strain over the different races. The closest approach so far to a good system of regulating such a fishery is the idea of weekly closed seasons. The effectiveness of such a system will depend, however, upon the length of time that it takes a group of fish to migrate through the fishing area, in the case of the commercial fishery. If the closed season is of such short duration that it merely affords an opportunity for more fish to get into the fishing area but not through it, it may be ineffective in permitting the escapement of adequate numbers of the various groups that happen to migrate through the fishery during the period of its ■ greatest intensity. Preliminary tagging experiments have been carried out in the troll fishery and indicate a fairly wide-spread and indiscriminate mixing of fish from different regions, although there appears to be a partial divi- sion at about Point Arena of fish arising from the central California and northern California rivers. The number of tags released and recovered in the different years is shown in Table 6. TABLE 6 Number of Tagged Salmon Released and Recovered in Various Years Salmon Tagged Year North of Point Arena South of Point Arena Total King Silver King Silver 1939 550 548 1,027 1,149 0 7 8 95 144 396 321 514 211 303 111 7 905 1940 1,254 1941 1,467 1942 1,765 Totals 3,274 110 1,375 632 5,391 Salmon Recovered Year North of Point Arena South of Point Arena Oregon Washington Total Offshore Rivers Offshore C. V. Rivers 1939 1 6 5 15 2 2 2 10 31 1 4 5 4 14 13 8 30 51 77 13 1 1 3 5 16 1940 44 1941 1942 1943- 1 1 2 74 143 31 Totals. 29 46 40 179 10 4 308 These tagging experiments were not carried out in such a manner as to give quantitative results. While a fair number of tagged fish were released, the effort it was possible to expend upon watching for tags in the markets and fishery, as well as on th.e spawning beds, was not suffi- PKOGRAM OF MARINE FISHERIES 109 cient to give any idea of the actual number of tagged fish caught or returning to the rivers. The consistency of the results from the three years of tagging, however, does permit several conclusions on general distribution and origin of the fish which support the California outside troll fishery. Few salmon taken in California waters apparently enter streams north of the California line (Clark and Hatton, 1942). As indicated by results obtained in the tagging experiments by Williamson (1927) in which the salmon were tagged off the coast of British Columbia and recovered in rivers south of there as far as the Sacramento, it is evident that the California streams not only provide the bulk of the fish taken off the coast of California, but also probably provide some of the salmon for the troll fisheries in the far north. We can presume, therefore, that the regulation of the California troll fishery will benefit the races of salmon that depend upon the California rivers for their spawning grounds. An intensive tagging program will be required to define the dis- tribution of fish in the ocean and their relation to the various rivers. It is possible that the marking of young fish may be resorted to if some assurance can be obtained through experimental work that the marks used or developed will give results that will be representative of the reactions of the unmarked fish. The tagging experiments will be required to determine the rate of movement of various runs through the fishing area. In the tagging of adults, the size of the program will undoubtedly be somewhat limited by available personnel for some time. -It will hardly be worthwhile to do such tagging on a small scale over a long period. Tagging should be intensive and may be planned either to cover the whole coast of California at the same time or may be concentrated in one area. Whatever plan is finally adopted, it must be remembered that the release of tagged fish is the smallest part of a salmon tagging program. Significant results will then depend upon an intensive search of the fishery for recaptured specimens as well as a thorough inspection of all spawning areas. Experimental work has been carried on in the past season in an attempt to use tagging of adult salmon in the streams as a basis for estimating the total number of fish migrating into a particular stream. This, supplemented where possible by counts on the spawning beds, appears to be an economical way of making such estimates, and is much more practical than the installation of expensive weirs on every stream that it is desired to study. The almost annual loss of the count of some part of .every run through the enforced removal of weirs during flood periods casts doubts upon the accuracy of the counts that depend upon them alone. It is quite obvious that we cannot concentrate our efforts upon one stream and expect to extrapolate the results freely to others. Size Limits There is a rather strange relationship, in the case of an anadromous fish such as the salmon, between the size limits as imposed on the inland fisheries, and those imposed on the outside fisheries. At present the California Fish and Game Code prescribes a minimum size of mesh for the nets to be used in the river fishery. The purpose of this is apparently to prevent capture of small salmon. 110 CALIFORNIA FISH AND GAME Such a regulation would be perfectly understandable in the case of a fish that was growing. However, in the case of a salmon which has reached maturity, and has ceased feeding when it enters the delta fishery, this regulation is directly opposed to the principles of selective breeding. The minimum size mesh of 1\" during the principal salmon fishing season permits the escapement of the precocious male salmon called ' ' Jack salmon ' ' and the smaller females. At the same time, it encourages the capture of the largest males and females. Thus, instead of follow- ing the accepted practice of livestock raisers who market their less desirable stock and reserve the largest and best stock for breeding pur- poses, the mesh regulations in the river salmon fishery must be such as to take a disproportionate toll of the larger, most desirable fish, and to preserve the smaller and less desirable ones for breeding purposes. Pres- ence of heavy runs of the small-sized Jack salmon on many of the streams along the west coast of North America undoubtedly is associated with similar ill-conceived mesh regulations. An intensive study of sizes of salmon and the effect of various sized meshes of gill nets must be undertaken in order to determine the policy that should be pursued in handling this situation. It is not desirable that we should continue a regulatory program that will have as its even- tual result the development of a pigmy race of salmon. On the other hand, no changes should be made in these regulations until adequate study has indicated a safe course to follow. The relations between mesh size and fish survival are too complex to blindly discard old or adpot new regulations. Such unsubstantiated action might be far more harmful than present practices, however ill-advised they may be. On the other hand, the effectiveness of present size limits imposed upon the ocean troll fisheries must be studied, from a different stand- point. It is highly probable that these size limits are beneficial, if proper care is taken to release small fish from the hooks without injury. Scope of Program The salmon program, in order to be effective, must be state-wide in its scope. Plans now being drawn up by the Army Engineers indicate the possibility of a series of dams being constructed in the Klamath and Trinity rivers. Definite plans are being made by the U. S. Bureau of Reclamation for a series of dams on the Upper Trinity River in the vicinity of Fairview. Whether or not these dams are constructed, any salmon program that has for its object the proper protection of the species must include the Klamath and Trinity rivers, as well as the other rivers in which salmon spawn. Phobably it will be necessary to concentrate the efforts of the staff in the Central Valleys for the present in order that proper provisions may be made for the fish in this area in the planning of the various reclamation and flood control projects. The salmon programs in the northern streams must be taken up, however, in conjunction with the offshore conservation program unless plans for water development force the institution of intensive investigations there before that time. One important problem that must be faced is determination of the efficiency of the artificial propagation of salmon in terms of fish taken by the sport and commercial fishermen. This will involve first of all development of a method of marking young fish that will not decrease PROGRAM OP MARINE FISHERIES 111 ** -. c**v he rB<^v « "iL Fig. 27. Indian "Weir at Hoopah on the Trinity River. While in operation, until taken out by the first heavy rains, this weir is an effective block to the early fall salmon. their chances of survival as do the rather drastic methods now used of removing two or more fins. We have already lost in the neighbor- hood of 75 per cent of the original salmon spawning area in the Central Valleys streams. With the construction of more dams there, and in the Klamath and Trinity Rivers, we will lose much more. We must know if it is economically and physically possible to substitute hatcheries for some of these natural spawning grounds. Summary The salmon program will undertake first the determination of the flow of water that must be provided in each stream below the lowest impassable dam planned by the Army Engineers or Bureau of Reclama- tion in order to maintain the most efficient size of salmon run for that particular stream. In order to protect the runs of fish which exist or will be built up below such dams, efficient fish ladders must be con- structed over smaller diversion dams that lie below the spawning grounds. The young salmon must be protected during their down- stream migration by the installation of adequate screens wherever required by the combined considerations of location and type of diver- sion, schedule of water use, and the schedule of downstream migration of the young salmon. Experience with both fish ladders and screens now installed in the Central Valleys area indicates that a spceial crew will be needed by the 1 1 -J CALIFORNIA FISH AND GAME Fig. 28. Upper Trinity River. This section of stream will be inaccessible forever t< salmon and steelhead upon completion of a dam at Fairview and diversion o: the Trinity River from the Trinity Watershed into the Sacramento River. Division to supervise the maintenance and proper operation of th< screens and ladders. One of the biggest problems in this regard is th< development of a fish screen that will prevent the loss of great number! of small salmon migrants. An adequate flow of water below any of tin dams planned in the Central Valleys area, with the exception of Tabl< Mountains, will ensure the perpetuation of good-sized salmon runs ir practically all of the streams, since good spawning beds of adequate siz< will remain, even though a considerable portion of the spawning are? in the State will have been blocked off by these dams. With the installa PROGRAM OF MARINE FISHERIES 113 tion of efficient fish ladders and proper types of fish screens, there will be little danger of further depletion from this source. The conservation of the fisheries, aside from the protection of the spawning adults and the young, will involve a tagging program of some magnitude, and probable a study of the racial characteristics of the salmon in an attempt to separate the fish into different streams by anatomical characters. It is important that the relationships of the runs from the different streams to the fisheries along the different parts of the coast of California be understood, that the time of these runs be defined, and their size be studied in order that we may arrive at sime measure of the size of the fishery that should be allowed. Practicability of such an extensive investigation as will be involved must be carefully scrutinized before a research program of any magnitude is undertaken. TUNA In the remaining fisheries of the State, the data collected and ana- lyzed are not yet sufficient to permit a clear discussion of programs. The principal fisheries that must be tackled first are the tuna and mackerel. 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i i FOUR SPECIES OF TUNA TOTAL CALIFORNIA CATCH (Bonito not shown) r 100 - / / \ \ A / \ /' \ / \ a X 3 o a. o ? 50 o !j ■ - A / A / \ / $/ \ \ \ \ / \ \ --t^sk r^ Ay \ / ^ a o tJ* CT <-t CO * * 1 1 o cd a- * pr en > o cd ■5' CD CO 9 CD -t cr V CO > o •3' CD CO o cr cd »-t cr &S CO 1 > o o •3' CD CO o tr CD •-i cr V to t > •5' CD •-* to i o CD Er F O O •5' CD CO 9 cr CD cr 6f i > CD CD •5' CD »1 CO 2 CD- CD -» CD- CO Si 19- J Check 1 8 13 4 3 1 1 1 7 2 14 10 8 15 1 1 2 3 6 6 6 11 2 1 4 6 10 27- J Feed* 9 2- P Feed* 1 8 7-Q Check _ 2 2 2 9 ' Artificial feeding started on these two areas March, 1943. " Bullet hawks. Pig. 39. Mouse and rattraps used in comparative rodent counts on fed and nonfed areas. A line of 34 stakes placed 30 feet apart, totaling 330 yards in length, was laid out in each area. Three traps were placed at 33 of the stakes, one at the 34th, making 100 traps per line. The lines were run for five consecutive nights (500 trap nights) in the spring and fall of each year. 144 CALIFORNIA FISH AND GAME 100 I9J CHECK i 1 100 27J FEED i 2P FEED 100 Li i 100 7Q CHECK ■fir i o 2 42 < Q. ~> < •>TT1h 3 o L 'a:1 Q. < 1943 23 1944 FTT o o < Q_ ~> < 45 -SPARROWS -COTTONTAILS -JACK RABBITS -RODENTS Fig. 40. Graph of populations of quail competitors on fed and nonfed areas. Solid bars indicate number of sparrows seen in passerine bird counts. Diagonal hatch bars indicate number of jack rabbits seen ; dotted bars number of cot- ton-tailed rabbits seen during passerine bird counts. The open bars indicate number of rodents trapped in the comparative rodent trapping censuses. Feeding started on the 27-J Feed Area and the 2-P Feed Area March, 1943. KETTLEMAN HILLS QUAIL PROJECT 145 The traps were set each night for five consecutive nights in each trap- ping period, making a total of 500 trap nights. Only the total of rodents actually caught is shown in Fig. 40. "Sprung" traps were counted but not tabulated here, since much of the springing was done by birds in the late evening or early morning. Possible mammal predators on quail were checked by means of track bed counts. Ten permanent trail spots each about ten feet long were chosen along pathways commonly used by coyotes, foxes, skunks, etc., in each of the four areas of the feed experiment. These were run for three successive nights in each area. The sites were visited the evening before each count was to be made and "dusted" by using a piece of brush. The following morning the sites were visited' and a reading made of all tracks seen. A summary of all these counts is given in Table 2. Only coyotes, kit foxes, bobcats, house cats, and skunks are listed among the mammal predators. Koadrunners are also given. Many other tracks, such as rabbits, quail, and small rodents, were seen, but in general were too numerous to obtain any exact counts or comparisons. are Fig. 41. Predator track census spot. Ten such permanent trail spots were chosen in each of the experimental areas. The spots were "dusted" each night for three nights to make tracks register. A reading and tabulation of tracks was made the following mornings. 146 CALIFORNIA FISH AND GAME TABLE 2 Results of Predator Track Counts on Fed and Non-Fed Areas Area 19- J Check. 27- J Feed*. 2- P Feed* 7-Q Check Feb., 1943 7 6 11 10 SO o May, 1943 W Aug., 1943 Feb., 1944 16 19 15 12 w Aug., 1944 11 14 11 11 SO Feb., 1945 11 12 12 11 SO o * Artificial feeding started on these two areas March, 1943. ** Mammal predators listed include coyotes, kit foxes, skunks, house cats, and badgers. While it is possible that some predators tended to avoid such man- treated trail spots, a study of tracks leading to the census spots did not show that such was a fact. If any such avoidance was present, it was probably equal on fed and non-fed areas. Results of the Artificial Feeding Program A glance at the summary of quail censuses and the summary of old- young ratios seems to show that a small, but consistent increase of quail has been obtained by feeding quail on scratch feed. The gains made, however, are nowhere near as startling as those obtained at Dune Lakes under a program of artificial feeding plus predator control. In our experimental program of predator control conducted at the Shandon Experimental Area, much more startling results were obtained by one year's control of quail predators than are here shown by artificial feeding alone. This suggests that the Dune Lakes results were largely due to predator control, although the combined program could conceivably have been more effective than the sum of the two component parts — feeding or predator control, — applied separately. TABLE 3 Mass Fall Censuses of Quail at Kettleman Hills on Fed and Non-Fed Areas Number of quail Area September, 1942 September, 1943 November, 1944 19- J Check.. 283 145 321 315 231 163 421 315 231 27- J Feed* 200 2-P Feed* 410 7-Q Check 201 ' Artificial feeding started on these two areas March, 1943. KETTLEMAN HILLS QUAIL PROJECT 147 While some readers might interpret the increase of quail under these artificial feeding conditions as an indication that feeding is a recom- mended practice for increasing quail, the authors feel that the results as shown at Kettleman Hills do not justify the costs. A comparison of the counts taken after feed was supplied with the 1942 counts in Table 3 shows a small increase indeed for an outlay of some 400 sacks of grain at an average price of three dollars per sack over the interval that feeding has occurred. It is possible that feeding would show greater returns in other areas less blessed with natural quail foods than Kettleman Hills, but it is our feeling that many other more effective and economical quail management methods should precede attempts at artificial feeding. The comparative censuses of the various quail competitors such as small rodents, crowned sparrows, and rabbits likewise do not show any startling increase in these species under the artificial feed conditions at Kettleman Hills. A study of Fig. 40 shows that rodents apparently increased more on the 2-P Feed Area than on the 7-Q Check Area. These differences were minor in the winter counts, but the April, 1944 trapping period when roughly seven times more rodents were trapped on the feed area than on the check area, and the April, 1945 period when an even greater difference was noted, indicate that rodents increased under the feed program. It is possible that had not a part of the rodent popula- tion built up on the feed area been killed off by our trapping in the spring periods, the increment would have bred up and shown significantly on the fall counts. The figures as indicated by our trapping do reveal that feeding resulted in increases in the rodent population in the spring and point to the probable ultimate outcome of such artificial feeding. No very great increases were noted in the populations of rabbits or seed-eating birds as seen by our counts. However, it is felt that large numbers of crowned sparrows were attracted by the artificial feeding. Visits to the feed lanes immediately after feed was scattered showed large flocks of Gambel sparrows and golden-crowned sparrows feeding on the scattered grain. These flocks evidently moved in from non-fed areas. They did not show up significantly in our comparative counts. No simi- lar concentrations were ever noted on the non-fed areas. A similar short-term, local attraction of cottontail rabbits immedi- ately after feed was scattered was apparent. This factor also failed to show up on our index counts as summarized in Fig. 40. Predators on quail and on other animals that might have been attracted by the feeding, such as the various hawks and fur-bearers, failed to show any appreciable increases on the fed areas. (See Tables 1&2.) From these results, it would appear that we were not successful in building and maintaining a quail population much above normal by arti- ficial feeding, nor were there any indications that populations of seed- eating birds built up permanently. Rodents, however, showed a sig- nificant tendency to increase or be attracted to the feed. The Quail Watering Experiment For a number of years, the Division of Fish and Game, the U. S. Forest Service, and other agencies have been placing quail drinking fountains in the drier regions of the state to extend valley quail range into areas that are good quail habitat except for water. Abundant quad 148 CALIFORNIA FISH AND GAME water is found at Kettleman Hills in the vicinity of the oil wells. How- ever, there is a belt around the edge of the Hills, away from the oil field, that seems to have abundant cover and feed, but has no water. This belt probably resembles the condition of the whole Kettleman Hills prior to oil development. No quail whatsoever are found in this area in the middle of the summer and early fall. With the advent of winter rains, however, some quail from the watered part move to this summer-dry area. In the spring, prior to the onset of summer drought, a few quail nest in this waterless belt. To test the best means of stocking such an area that has been recently supplied with new watering places, the fol- lowing experiment was designed. Four areas, each comprising about 200 acres, in separate, compar- able canyons on the dry, northwest slope of the Hills, were chosen. One of these (control canyon) was to be left absolutely dry; the other three were supplied with artificial quail water. One of the three watered areas (Tank No. 3) was left alone after water was supplied (no quail were introduced to see if birds would move in naturally from other places occupied by quail) ; at another (Tank No. 1), a covey of 23 quail marked with numbered and colored bands was released as a group in October, 1942; at the remaining installation (Tank No. 2), 23 similarly banded quail were penned for several days in a coop which was placed at the water. Three to five birds were released each day after they had been penned for a week. Periodic checks were then made on quail use. Fig. 42. One of the "vacuum type" quail drinking fountains used in the experiments to test ways of introducing birds into newly watered areas. This installation consists of a 50-gallon drum insulated in earth in a redwood box. The top bunghole of the drum is sealed airtight except when filling. A |" pipe leads from the bottom of the drum to a drinking basin under the shade in the fore- ground. The device operates on the same principle as a vacuum type chicken watering fountain. KETTLEMAN HILLS QUAIL PROJECT 149 During the first autumn that the experiment was run, the following- results were noted. No quail were seen about either Tank No. 3 (the one at which no birds were released), or in the non-watered canyon. The 23 quail that were released as a group at Tank No. 1 all disappeared shortly. Of the 23 quail released gradually at Tank No. 2, some remained about the pen for a few days during the release period, but as soon as all were turned loose, no more were seen about the site. Regular horseback quail censuses were made on all four areas during the fall and winter of 1943 and 1944. No birds were seen in the immedi- ate vicinity of these watering places, although wandering coveys were in the general part of the Hills covered by the four watering experi- mental areas. In the summer, however, quail (not part of the banded release) were seen watering at all of the tanks at various times during the summers of 1943 and 1944. No birds would ordinarily be found in this area in the summer without some water supply to hold them. It seems, in concluding this experiment on ways of introducing quail to formerly dry areas which have been recently supplied with quail water, that the best procedure is to let nature take its course. Provided that a stock of native birds is present anywhere in the vicinity (in our case, permanent water was no farther than two miles from any instal- lation), native birds will use the newly placed water. In our experi- ments, two attempts to release birds at these new fountains resulted in failure, yet in the succeeding summers native birds availed themselves of the same watering installations. Although birds were not found about these installations in the win- ter, it is felt that the new waters will bring about an increase in quail abundance which will result in more winter use of these areas. This has been the history in other parts of the Hills where new water has been added. Ideal Development Experiments An early diagnosis of the deficiencies in the quail environment of Kettleman Hills pointed to the lack of water and cover (particularly roosting cover) as the two main components that need attention in order to build a maximum crop of quail. With these two factors in mind, one area, 33- J or "the ideal development area," was chosen in which to con- duct tests on the best species of cover for local conditions and to experi- ment with various methods of supplying water for quail. While many of our early experiments with water and cover were done in this area, tests were also made throughout the Hills at spots which looked as though the addition of cover or water or both would result in a new quail covey center. Since this work started in the fall of 1942, and barely two years have elapsed since the planting program was well under way, it is too early to give definitive results on the quail population. However, in many cases where sufficient growth has resulted since the time of planting- cover, new covey centers have become established. Of particular note is one new covey of roughly 50 birds which has appeared in a formerly barren spot in the ideal development area. Water had been available for birds at an oil well, but conditions surrounding the immediate vicinity were such that no cover was present or could be planted. By carrying 150 CALIFORNIA FISH AND GAME the water in scrap pipe to a more favorable spot in a small canyon 150 yards distant and developing cover about the new drinking site, in two years a new covey center was created. Similar results were obtained in other places on the Hills where our plantings grew to an amount suffi- cient to furnish cover for quail. Escape cover is, in general, ample over the part of the Hills encom- passed by the oil developments. However, there are some areas in which sheep grazing has seriously damaged the native quail brush (Atriplex polycarpa) . This damage is concentrated in areas of several hundred acres each in size surrounding the few watering places suitable for sheep. Our work has shown that protection from sheep graz'ing can result in restoration of the quail brush in two years. Additional protection given to the native quail brush by fencing small plots against rabbits will result in seedlings attaining a size which is sufficient to withstand rabbit browsing. Such fencing is deemed desirable only in small plots about watering installations, and even here only at certain drinking places known to be frequented by large rabbit populations. In general, the native quail brush will furnish cover in two or three years if water is merely allowed to seep on the ground about the quail drinking fountains. This procedure is possible under Kettleman Hills conditions, since the oil companies have been very generous in allowing use of their water. Most of our experiments in cover planting were designed to supply roosting cover. The local quail roost in the low Atriplex polycarpa (3-47 high), but prefer higher, denser roost trees which probably furnish more protection from mammal predators. In our experience, the best roost tree for quick growth and maximum quail value at Kettleman Hills and the west side of the San Joaquin Valley generally is the evergreen tamarisk, or "tamarack" as it is locally known. Eoughly 2,000 slips of this tree were put out to supply quail roosts. This tree was felt to be ideal in this area for the following reasons : (1) It grows rapidly. (One of our plantings grew nine feet in one year.) (2) It is hard to kill off once it is past the first year's growth. (3) It requires but a small amount of water for survival after the first year. (4) It grows very readily from a cutting if placed in moist earth. (5) The cost of cutting stock is practically nothing since all that is required is to cut slips from already existing plants. (6) It will not spread into adjacent range land in the absence of water since its seeds will not germinate unless fairly moist con- ditions are obtained. Such was the case at Kettleman Hills. It must be noted that this tamarisk will become a nuisance on irri- gated lands in some sections of the state. Tamarisk at the Hills has been found to supply excellent quail roost in two to three years, if growing in a moist situation. The growing habit of the tree may be modified to supply better quail roost by pruning the terminal shoot of the tree. No other trees were found to be anywhere near as successful or adaptable to Kettleman Hills conditions as were tama- risk. KETTLEMAN HILLS QUAIL PROJECT 151 Fig. 43. One of the successful cover and roost tree plantings in the "ideal development area." The trees are evergreen tamarisk (T amarix articulata) . Pampas grass acts as additional ground cover at the water fountain. The plantings were made in January, 1943 ; picture taken March, 1944. Various species of willows obtained from Fresno and San Benito Counties were planted, but required too long a time for dense growth to compete with tamarisk as a roost tree here. Probably the second most successful roost-like cover plant tested at the Hills was Coast quail brush or lenscale (Atriplex lentiformis) obtained from Monterey and San Benito Counties. These plants pro- vided excellent roost and escape cover after about two years' growth, attaining a height of seven feet in one case. Other plants that were tested and which showed promise as escape cover locally were wild gooseberry, both wild and domesticated rose, various varieties of blackberry, pampas grass, mule-fat or arrow-weed (Baccharis viminea), and various species of cacti, both the flat-stemmed and round-stemmed varieties. The gooseberry is a little slow to take hold, but ultimately furnishes excellent escape cover, the same being true of wild rose. The blackberry has a fairly high moisture requirement, and hence its use is limited to the vicinity of water. Pampas grass showed a very rapid growth when small clumps were planted, furnishing excellent dense cover about watering places. Baccharis viminea grows readily but many individual plants must be set out in dense clumps in order to obtain a thick enough growth to furnish sufficient cover. All of the above species were planted merely by taking cuttings or sections from existing growth in neighboring localities. Some success was had by seeding various other plants, although this method is not considered as effective as is the planting of slips. 152 I CALIFORNIA FISH AND GAME . ,,;.« Fig. 44. Showing growth of introduced Coast quail brush (Atriplex lentiformis) planted August 29, 1942. Upper photograph, March 10, 1944 (18 months after plant- ing) ; and lower photograph, November 1, 1944 (26 months after planting). KETTLEMAN HILLS QUAIL PROJECT 153 Cover species tested for growth from seed planting were the local Atriplex, which was tested under many conditions, screw-bean mesquite, and several shrubby species of buckwheat. The only one that did well was the native Atriplex (Atriplex poly car pa) . Fig. 45. An early quail water development at Kettleman Hills. Water lines used for fire protection at the oil wells were tapped with \" pipe and a basin placed nearby. It was found that quail used these installations more readily if the water was conducted to a spot having better quail cover. *.r '■ Fig. 46. 'Here water was carried several hundred feet in scrap pipe to a shaded drinking trough located in a spot better suited to quail. Drippings from the water basin resulted in enormous growth of the local quail brush. L54 CALIFORNIA FISH AND GAME Fig. 47. A self-filling- quail watering- device, the "gallinaceous guzzler" at Kettleman Hills. The oiled-earth collecting apron collects winter rainfall into a 750-gallon subsurface tank, 30" deep. A sloping trough is connected to the tank. Water in the trough and tank is in hydrostatic level. As the water level lowers throughout the summer, birds merely walk farther down the sloping trough to g-et their drink. Several types of watering devices were developed and tested through- out the Hills. In general, water was supplied from high pressure lines of the two principal oil companies. We tapped these lines with \" pipe and supplied high pressure valves which were left open only enough to allow water to drip into shallow, concrete basins. Roughly 50 new watering sites of this type have been placed throughout the Hills by the Division of Fish and Game. While water was available at many of the oil wells, lack of cover and excessive human activity rendered much of this water valueless to quail. Consequently, much of our effort has been toward piping this water a distance from the bare area around the well to a clump of cover, or to some place where cover could be developed. Scrap supplied by the oil companies furnished most of the pipe for taking water to more advan- tageous situations. Most of the watering installations so placed were fitted with a valve which was left slightly open, thus supplying wrater for cover plantings about the drinking fountain. In some areas, where water conservation was a problem, float valve installations such as have been employed by the Division of Fish and Game in other development work were placed on low pressure lines and tended regularly to see that the valves worked freely. The inverted siphon tank, which consists of a 50 gallon drum sealed at the top with an outlet into a basin of water, was also used. This inverted siphon tank works on the same principle that the ordinary vacuum chicken watering fountain operates. KETTLEMAN HILLS QUAIL PROJECT 155 Two self-filling watering units requiring little or no maintenance were placed in parts of the Hills not supplied with pipe lines. These devices are 750 gallon, concrete tanks placed underground. A sloping drinking trough is attached to the side of the tank, allowing quail to follow the gradually receding water to the level of the bottom of the tank. The units are filled by winter rainfall on oiled earth collecting aprons draining into the tanks. A complete description and specifications of these ' ' galli- naceous guzzlers" will be found in Glading, 1943. THE DEVELOPMENT PROGRAM As a result of the experimental work conducted at Kettleman Hills, a long-time quail program on the Hills has been formulated. It is planned to use this area as a "natural game farm." Quail will be increased in number by the various technics developed in the course of the experiments here and in other experimental areas in the State. Cover and water will be supplied as far as economically possible throughout the North Dome area, ultimately looking forward to a large quail population from which the annual surplus may be removed for stocking other areas in Fresno and Kings Counties, and, as time goes on, throughout the State. In general, in accordance with our findings, feed will not be supplied to the birds, except in pre-baiting selected spots for trapping birds to be transplanted to other areas. However, roost trees, principally tamarisk, and some loafing or escape cover, principally, Atriplex lenti- formis, gooseberry, blackberry, and pampas grass, as well as water will be supplied where needed. Any water developments that will be placed distant from existing coveys will be merely allowed to restock themselves naturally in accord- ance with our findings on the dry area restocking experiments. Our first trapping of quail for transplanting will probably be done in the fall of 1945 or 1946, since it is felt that our development program has now reached the stage where we are justified in removing a limited number of birds for a general transplanting program. SUMMARY Experiments were set up at Kettleman Hills to determine whether or not artificial feeding of quail was practical. A slight increase in quail, and some negligible increase in rabbits, seed-eating birds, and predators was noted. An increase in rodents showed in our counts. It was not felt that the slight increase in quail justified the cost of arti- ficial feeding. Experiments were set up to determine the best means of stocking an area formerly devoid of water and quail to which water had been supplied. It was found that if quail are naturally present within two miles of such new installations, the best procedure is to " let nature take its course" and allow birds to move in from surrounding areas rather than to try to stock this area with birds planted from a bulk or gradual release. The best means of developing quail on the Hills was found to be to rectify the two principal deficiencies found in this area ; that is, lack of water and lack of roosts. Water was supplied principally by tapping 156 CALIFORNIA FISH AND GAME oil company lines, and roosts were supplied mainly by the addition of evergreen tamarisk. The ultimate aim on the area is to make it into a "natural game farm." To this end quail management technics developed here and throughout the State generally will be applied, leading, it is hoped, to an increased quail population on Kettleman Hills from which an annual trappable surplus will be removed. Literature Cited Glading, Ben 1941. Valley quail census methods and populations at the San Joaquin Experi- mental Range. Calif. Fish and Game, Vol. 27, pp. 33-38. Glading, Ben 1943. A self-filling quail watering device. Calif. Fish and Game, Vol. 29, pp. 157-104. Grinnell, Joseph and Storer, Tracy Irwin 1924. Animal life in the Yosemite. Univ. Calif. Press, Berkeley, I-XVIII, 1-752. Townsend, M. T. 1935. Studies on some of the small mammals of central New York. Roosevelt Wild Life Annals, Vol. 4, pp. 1-120. A NEW FISH SCREEN FOR HATCHERY USE ' By J. H. Wales Bureau of Fish Conservation California Division of Fish and Game Anyone who has raised domesticated trout or has managed them in natural waters knows how difficult it is to make them stay in their proper places. It seems that they are forever trying to get out of a hatchery pond, or out of a stream into an irrigation ditch. A great deal of thought has been given to these problems and many screens have been devised to keep the wandering trout at home. The latest, a modification of the self-cleaning revolving type, has recently been developed at the Mt. Shasta Fish Hatchery by Mr. Robert Murray, and offers great promise. To begin at the beginning, about the year 1865, we find in "Amer- ican Fish-Culture" by Thaddeus Norris the following description: "Seth Green, at Caledonia creek, that he may prevent the fish in his ponds from running up into the mill-pond that supplies them, has a water-wheel turned by the current at the head of the raceway, the edges of the buckets or paddles coming so close to the concavity of the frame in which it revolves, as to keep the fish from ascending, while those from above can descend between the buckets. Floating grass and leaves also pass without obstruction. This contrivance, however, although it will keep the large fish in the last pond, will not prevent those of pond No. 1 from running down into No. 2, and the fish of both from getting into pond No. 3, where the yearlings would be devoured." 1 Submitted for publication, January, 1945. Photographs by author. Fig. 48. The Murray fish screen in operation. ( 157 ) 158 CALIFORNIA FISH AND GAME As Mr. Norris points out, the paddle-wheel at Caledonia Creek was not entirely satisfactory. It did pass floating grass and leaves, which a stationary screen would not do, but it also allowed the downstream passage of fish. It seems obvious that from this simple beginning some thoughtful trout-culturist devised the so-called "California rotary fish screen. ' ' The date of its invention is apparently unknown ; it was described in California Fish and Game for October, 1928, but had cer- tainly been in use for some years previously. This revolving screen is little more than Seth Green's paddle-wheel covered by wire mesh. Thus fish cannot swim between the paddles, and floating debris is passed on downstream. This second step in the evolution of the revolving screen must have seemed like an ingenious device to its inventor but it had one very serious shortcoming. The paddle-wheel was naturally of the "under-shot" type and the debris which collected on the screen had to go down and under the wheel. This difficulty was partially met by a ' ' draper board ' ' which caught the debris at the lower edge of the screen and held it there until sufficient pressure was built up. Then this draper board suddenly released, swung down, and allowed the debris to float under the screen. The draper then returned to its position, but in this automatic cleaning process many fish must have been allowed through with the trash. The next forward step in the evolutionary process of screen develop- ment was described by W. H. Shebley (State of California, Fish and Game Commission, 22nd Biennial Report for 1910-1912, pp. 42-43, with fig.), and has been called the "Requa Screen" after its inventor R. W. Requa. Although its published description appeared earlier, it is actu- ally a more advanced design than the one discussed in the preceding paragraph. The Requa model had the circular screen and the paddle- wheel turning on separate axles, with the latter set in the flume box downstream from the former. The water passed through the screen Fig. 49. End view of screen removed from mounting. NEW FISH SCREEN FOR HATCHERY 159 cylinder, then turned the paddle-wheel. The axle of the paddle-wheel had a crank at one end, connected to a drive shaft. The drive shaft had a pawl at the opposite end which engaged the teeth of a ratchet wheel on the drum of the circular screen. By this clever arrangement the paddle-wheel turned one way and the screen turned another. The debris which collected on the screen was carried up and over the top of the screen. With this plan of operation the screen could be sealed, fish- tight, by rubber drapers at the bottom and sides. Many of these assem- blies were installed between the ponds at the Mt. Shasta trout hatchery and operated satisfactorily with one exception. Large fish would try to pass the paddle-wheel from the downstream side and would be injured or killed, just as a long bodied animal like a horse would be caught if it were try to enter a barn through a revolving door. Fig. 50. Screen mechanism disassembled. This point was brought to the attention of Mr. Murray and after some experimentation he arrived at a unique solution of the problem. The new "Shasta screen" is like its immediate predecessor in that the paddle-wheel turns one way and the screen itself turns another, but Mr. Murray has placed the paddles inside the screen cylinder. In this last respect it is like the earlier "California Fish Screen", but it is unlike it in the respect that they revolve in opposite directions. As can be seen in the photographs, either end of the axle rests in a rectangu- lar hub which can be slid down in slots built into the side of the screen box. The screen can be easily adjusted to any height and it can be quickly pulled out for repairs. The level of the water above the screen is controlled by a dam board so that it is just above the level of the axle. The water pours over this dam board and down through the screen onto the "bucket" wheel. A fall of 4 inches is sufficient to operate it. On one end of the "bucket" wheel shaft (see Fig. 49) is a cam which activates a pivoted lever. On the upper end of this lever is a pawl which engages the ratchet wheel fastened to the end of the revolv- ing screen. This mechanism causes the screen itself to revolve in the opposite direction to that of the bucket wheel. The advantages of the new ' ' Shasta screen ' ' are : first, that it can- not injured trout with its paddles ; second, that it is so much more com- pact and easily moved ; and third, that its rubber drapers at ends and bottom are always in view and can be easily inspected. REPORTS FISH CASES January, February, March, 1945 Offense Number arrests Fines imposed Jail sentences (days) Abalones: undersize, overlimit, no license, closed season Angling: no license, use license issued to another, illegally taken fish, false state- ment to secure license, 2 rods, night fishing, closed season, closed area, spear within 300 ft. of stream, take sunfish closed season Bass: 2 outfits, no license, undersize Catfish: selling undersize Clams: undersize, closed district, overlimit, no license- Commercial: white sea bass aboard boat carrying round haul net, no license, failure to keep proper records Crabs: undersize Lobsters: uiidersi z.e Pollution Salmon: spearing Sturgeon. Trout: closed season, overlimit, snagging, below dam, gaffing Totals 21 47 14 2 51 15 3 2 1 3 1 16 176 5790 00 777 50 275 00 125 00 1,339 00 735 00 60 00 30 00 50 00 150 00 10 00 445 00 $4,7S6 50 GAME CASES January, February, March, 1945 Offense Number arrests Fines imposed Jail sentences (days) Crane Deer: closed season, female, spotlighting, doe, spike buck, forked horn deer dis- trict Wa., allowing dogs to run deer, night hunting Deer meat: unstamped, closed season Doves: closed season, overlimit, ship by parcel post Ducks: closed season, no license, overlimit, unplugged gun, after sunset, early shooting Firearms: refuge '- Geese: overlimit Hunting: no license, false statement to secure licenss Non-game birds Pheasants: hen, closed season, fail to tag, no tags Pigeons : closed season Quail : closed season Rabbits: closed season, no license Shooting from power boat Swans Tree squirrels Totals 28 15 3 39 7 7 8 2 23 2 2 2 26 7 3 175 $25 00 2,400 00 810 00 180 00 1,142 50 190 00 570 00 115 00 50 00 1,165 00 90 00 15 00 70 00 740 00 440 00 100 00 $8,102 50 70 70 ( 160 ) REPORTS llil SEIZURES OF FISH AND GAME January, February, March, 1945 Fish: Abalones 914 Catfish.'Ibs 299 Clams -- Fish traps is Lobsters oT Lobster receiver 1 Lobster traps 107 Sunfish 24 Trout White sea buss, lbs 5,537 Game: Deer i:; Deer meat, lbs I'A'i Doves... .-. II) Ducks 190 Geese 22 Killdeer 1 Pheasants 20 Pigeons : ' 3 Quail 1 Rabbits - 3 Shorebirds _ 3 Swans s 45142 6-45 4200 (Continued from inside front cover) BUREAU OF ENGINEERING JOHN SPENCER, Chief San Francisco Clarence Elliger, Assistant Hydraulic Engineer San Francisco Samuel Kabakov, Assistant Structural Engineering Draftsman San Francisco BUREAU OF LICENSES H. R. DUNBAR, Chief Sacramento L. O'Leary, Supervising License Agent Sacramento R. Nickerson, Supervising License Agent Los Angeles Lorraine Atwood, License Agent San Francisco ACCOUNTS AND DISBURSEMENTS D. H. BLOOD, Departmental Accounting Officer Sacramento BUREAU OF PATROL E. L. MACAULAY, Chief of Patrol (absent on military leave) San Francisco L. F. CHAPPELL, Chief of Patrol San Francisco CENTRAL DISTRICT (Headquarters, Sacramento) C. S. Bauder, Inspector in Charge Sacramento Northern Division A. A. Jordan, Captain Redding Jos. H. Sanders, Captain Sacramento A. H. Willard, Captain Rocklin E. O. Wriath, Captain Chico L. E. Mercer, Warden, Butte County Chico Taylor London, Warden, Colusa County Colusa Albert Sears, Warden, El Dorado County Placerville E. C. Vail, Warden, Glenn County Willows Louis Olive, Warden, Modoc County Alturas Earl Hiscox, Warden, Nevada County Nevada City Nelson Poole, Warden, Placer County Auburn E. J. Johnson, Warden, Plumas County Quincy Charles Sibeck, Warden, Sacramento County Sacramento Earl Caldwell, Warden, Ssahta County Burney Brice Hammack, Warden, Siskiyou County Yreka Fred R. Starr, Warden, Siskiyou County Dorris R. E. Tutt, Warden, Sierra County Loyalton R. W. Anderson, Warden, Tehama County Red Bluff C. L. Gourley, Warden, Trinity County Weaverville C. O. Fisher, Warden, Yolo County Woodland R. A. Tinnin, Warden, Yuba County Marysville Wm. LaMarr, Warden, Placer County Tahoe City Rudolph Gerhardt, Warden, Butte County : Gridley Walter Krukow. Warden, Shasta County Redding Geo. Shockley, Warden, Lassen County Susanville Southern Division S. R. Gilloon, Captain Fresno John O'Connell, Captain Stockton R. J. Little, Warden, Amador County Pine Grove L. R. Garrett, Warden, Calaveras County Murphys F. A. Bullard, Warden, Fresno County Reedley Paul Kehrer, Warden, Fresno County Fresno Lester Arnold, Warden, Kern County Bakersfleld C. L. Brown, Warden, Fresno County Coalinga Ray Ellis, Warden, Kings County Hanford H. E. Black, Warden, Madera County Madera Gilbert T. Davis, Warden, Mariposa County -Mariposa Hilton Bergstrom, Warden, Merced County Los Banos Wm. Hoppe, Warden, San Joaquin County ,v~. * Geo. Magladry, Warden, Stanislaus County Modesto W. I. Long, Warden, Tulare County visa la Roswell Welch, Warden, Tulare County Porterville F. F. Johnston, Warden, Tuolumne County --faon?1^a Donald Hall, Warden, Kern County Kernville COAST DISTRICT (Headquarters, San Francisco) Wm. J. Harp, Inspector in Charge San Francisco Northern Division Scott Feland, Captain Eureka Lee C. Shea, Captain Santa Rosa W. J. 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McDermott, Warden, Santa Cruz County Santa Cruz Warren Smith, Warden, Contra Costa County Antioch SOUTHERN DISTRICT (Headquarters, Los Angeles Earl Macklin, Inspector in Charge Los Angeles H. C. Jackson, Captain Los Angeles Western Division L. T. Ward, Captain Escondido F. W. Hecker, Captain San Luis Obispo Fred Albrecht, Warden, Los Angeles County Los Angeles Walter Emerick, Warden, Los Angeles County Palmdale Theodore Jolley, Warden, Orange County Norwalk E. H. Glidden, Warden, San Diego County San Diego R. E. Bedwell, Warden, Santa Barbara County Santa Barbara H. L. Lantis, Warden, Santa Barbara County Santa Maria Orben Philbrick, Warden, San Luis Obispo County Paso Robles L. R. Metzgar, Warden, Los Angeles County Los Angeles A. F. Crocker, Warden, Ventura County Fillmore A. L. Stager, Warden, Los Angeles County Los Angeles Henry Ocker, Warden, San Diego County Julian Eastern Division Tate Miller, Captain Arlington C. J. Walters, Warden, Inyo County Independence James Loundagin, Warden, Inyo County Bishop W. C. Blewett, Warden, Riverside County Indio W. C. Malone, Warden, San Bernardino County San Bernardino Erol Greenleaf, Warden, San Bernardino County Big Bear Lake Otto Rowland, Warden, San Bernardino County Victorville Cliff Donham, Warden, Riverside County Idyllwild R. J. O'Brien, Assistant Warden, Imperial County El Centro MARINE PATROL C. H. Groat, Inspector in Charge Terminal Island T. W. Schilling, Captain Monterey Kenneth Webb, Warden Monterey Kenneth Hooker, Warden, Launch Minnow Tiburon Walter Engelke, Captain and Warden, Cruiser Bonito Newport Robert Mills Newport N. C. Kunkel, Warden Newport Beach Leslie E. Lahr, Warden Wilmington Ralph Miller, Warden San Francisco G. R. Smalley, Warden Richmond T. J. Smith, Warden ^ San Diego Carmi Savage, Warden Santa Monica R. C. Schoen, Warden Terminal Island MARINE PATROL AND RESEARCH BOATS Cruiser Bonito, Newport Harbor Cruiser Shasta, Redding Cruiser Rainbow III, Antioch Launch Shrapnel, Suisun Launch Minnow, San Rafael printed in California state printing ofpice SACRAMENTO, 7545 GEORGE H. MOORE, STATE PRINTER