CALIFORNIA! FISH-GAME Volume 37 San Francisco, April, 1951 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 LEE F. PAYNE, President Los Angeles PAUL DENNY, Commissioner HARVEY E. HASTAIN, Commissioner Etna Brawley WILLIAM J. SILVA, Commissioner CARL F. WENTE, Commissioner Modesto San Francisco E. L. MACAULAY Executive Officer San Francisco CALIFORNIA FISH AND GAME PHIL M. ROEDEL, Editor.. _ Terminal Island Editorial Board RICHARD S. CROKER San Francisco WILLIAM A. DILL- - Fresno JOHN E. CHATTIN San Francisco California Fish and Game is a journal devoted to the conservation of wildlife which is published quarterly by the California Division of Fish and Game. Contributions should be sent to Mr. Phil M. Roedel, Editor, State Fisheries Laboratory, Terminal Island Station, San Pedro, California. Manuscripts must be typed, double spaced, and conform to the style of previous issues. The articles appearing herein are not copyrighted and may be reproduced else- where, provided due credit is given the authors and the California Division of Fish and Game. This periodical is sent free of charge to interested persons, who may have their names placed on the mailing list by writing to the editor. Subscriptions must be renewed annually by returning the postcard included with each October issue. Subscribers are requested to notify the editor immediately of changes in address, giving the old address as well as the new. CALIFORNIA FISH and GAME "CONSERVATION OF WILDLIFE THROUGH EDUCATION" Volume 37 ISSUED APRIL 27, 1951 Number 2 TABLE OF CONTENTS Page Studies and Notes on Some California Marine Fishes John E. Pitch 311 Lampara Net-Pulling Gurdies J. B. Phillips 121 The Introduction of Kokanee lied Salmon (Oncorhynchus nerka kennerlyi) into Lake Tahoe, California and Nevada J. C. Fraser and A. F. Pollitt 125 The Embryonic and Early Larval Stages of the Tui Chub, Siphateles bicolor (Girard), from Eagle Lake, Cali- fornia Robert R. Harry 129 The M. V. Yellowfin, an Addition to California's Marine Fisheries Investigations Robert C. Wilson 133 Effects of Hunting Pressure and Game Farm Stocking on Pheasant Populations in the Sacramento Valley, Cali- fornia, 1946-1949 Harold T. Harper, Chester M. Hart, and Dale E. Shaffer 141 Food Habits of Feral House Cats in the Sacramento Val- ley Earl L. Hubbs 177 Toxicity of Zinc for Rainbow Trout {Sal mo gairdnerii) Joseph R. Goodman 191 Toxicity of the Roe of the Cabezon, Scorpaenichthys mar- moratus Carl L. Hubbs and Arne N. Wick 195 Yield of Hatchery Trout in California Lakes Brian Curtis 197 Notes A Noticeable Absence of Bladder Worms in Catalina Deer Merton N. Rosen 217 Composition of Deer Milk Herbert L. Hagen 217 Observations on the Failure of Gambel Quail to Breed Wallace Macgregor, Jr., and Manley Inlay 218 In Memoriam, Sam R. Gilloon 220 Reviews 221 Reports 227 ( 110 ) STUDIES AND NOTES ON SOME CALIFORNIA MARINE FISHES 1 By John E. Fitch Bureau of Marine Fisheries California Division of Fish and Game A number of rare or seldom-taken fishes came to the attention of the California State Fisheries Laboratory in 1!>4!) and 1950. The specimens listed here have not been reported previously. Electrona crockeri Bolin. Lanternfish. On May 16, 1949, a single specimen was taken from the stomach of a chilipepper (Sebastodes goodei) which was killed in the course of seismic exploration for offshore oil deposits. The fish was collected in 810 feet of water between Santa Barbara city and Santa Cruz Island (Lat. 34° 12' N, Long. 119° 40' W). In addition to the Electrona, the stomach content included one Cyclothone signata and some 20 to 25 hake (Merluccius 'product us) up to two inches in total length. The lanternfish was identified by Dr. Rolf L. Bolin of Stanford University. Eleven more of these small lanternfish were collected by Dr. Gordon Tucker, San Diego State College, during the summer of 1950. Dr. Tucker was engaged in deep trawling in the San Diego Trough some 17 miles off Point Loma using a net six feet in diameter made of one-inch stretched mesh. These important catches were made as follows: July 13, one in a horizontal haul at 900 feet; August 8, one in a horizontal haul at 1.450 feet ; August 23, one in each of three oblique hauls from 1,200 feet to 900 feet, 1,500 to 1,200 feet and 1.800 to 1,500 feet respectively; Septem- ber 6, one in an oblique haul from 900 to 600 feet; and September 7, one in an oblique haul from 1,200 to 900 feet and four in an oblique haul from 1,500 to 1,200 feet. The specimens have been sent to Dr. Bolin. Very few of these fish have been taken or recorded previously. Hygophum reinhardtii (Liitken). Lanternfish. A number of H. reinhardtii collected recently have come to the at- tention of the laboratory. These fish were taken at scattered localities well off the Southern and Baja California coasts and at the mouth of the Gulf of California. Listed in order of their capture they are : 1. March 13, 1950 : One specimen dipped at the surface under a light at N. B. Scofield Station 911, Lat. 31° 32' N, Long. 130° 16' W. 2. March 31, 1950: 34 specimens ranging from i] inch to If inches in total length were dipped from under a light by Walter Richards of San Pedro at Lat. 22° 53' N, Long. 107° 48' W. 3. April 10, 1950 : Five specimens collected at N. B. Scofield Sta- tion 927, Lat. 33° 00' N, Long. 127° 30' W. One was dipped under a light together with other lanternfishes including one Myctophum 1 Submitted for publication September, 1950. (Ill) Ill' i ALIFORNIA PISH AND GAME affine, five Myctophum californiense, and one Centrobranchus nigro-oct Hal us. Four were taken from the stomach of a jack mack- erel ( Trachurus symnn tricus) caught during the same night. The stomach contained two .1/. affini as well. 4. April 14. 1950: Two dipped under a light at X. B. Scofield Sta- tion 934, Lat. 34° 20' X. Long. 140° 11' W. Bolin (1939) lists but one record of this species from the Pacific Coast and that from the Gulf of California. The specimens discussed here will be deposited in the Stanford University collection. Albula vulpes (Linnaeus). Bonefish. A 12-inch bonefish was hooked and landed by Mr. William Graham on October 9, 1949. He was fishing in the upper bay at Newport Harbor and using clam for bait. These fish seldom wander as far north as this and are particularly unusual during the fall and winter months. Lactoria diaphana (Bloch and Schneider). Boxfish. Mr. George A. hieane snagged a small boxfish while fishing in the surf at Corona Del Mai- on November 8, 1949. These fishes are distributed in tropical seas throughout the world but have only been recorded from California by two authors (Hill. 19:52; Bolin. 1933). During November and December. 1!)32, at least 10 of these fish up to seven inches in length were collected between Santa Barbara and San Juan Capistrano, a little over 115 miles of coastline. The present specimen has been sent to Scripps Institution of Oceanography, La Jolla. Verrunculus polylepis (Steindachner). Triggerfish. (Figure 53.) A 15-inch triggerfish was taken on -January 5, 1950, in a drag net in 120 fathoms of water about eight miles east of Anacapa Island by the boat Jubilee, skipper Mark Mullenary. This tropical species is a not too infre- quent visitor to Southern California lint to the author's knowledge has not previously been recorded so far north. The specimen has been depos- ited in the collections of tin 1 University of California at Los Angeles. Figure 5o. Triggerfish, Verrunculus polylepis. Photograph by Al Johns for Haclen & Carpenter, San Pedro. NOTES ON CALIFORNIA MARINE FISHES 113 Alepisaurus borealis (Gill) Wolffish. (Figure 54.) On February 11, 1950, a four-foot wolffish was noticed swimming feebly in the surf near the mouth of Oso Flaco Creek just south of Pismo Beach. It snapped viciously at a youngster who was attempting to catch it. Mr. Harold Foster of Pismo Beach, who was digging clams nearby, finally captured the fish by throwing it onto the beach before it could bite him. This specimen has been deposited in the collection of the University of California at Los Angeles. Figure 54. Wolffish, Alepisaurus borealis. Photograph by Al Johns for Vernon M. Haden, San Pedro. A previously unrecorded specimen four feet long was picked up dead on the beach at the mouth of Oso Flaco Creek during March 1945. A photograph of the fish was sent to the California State Fisheries Labora- tory by Fisli and (fame Warden R. E. Jeffries. During the summer of 1950. a 53-inch wolf fish was taken from the surf near Pt. Sal (just south of Oso Flaco Creek) by Mr. John W. Taylor of Los Angeles. This third A. borealis was reported to the laboratory by Warden II. L. Lantis of Santa Maria. The most recent capture was made by the crew of the Cali- fornia Division of Fish and Game research vessel N. B. ScoFiELDsome 240 TABLE 1 Measurements in millimeters and counts on two Alepisaurus borealis Measurements Standard length Total length Head length Upper jaw Dorsal base Anal base Pectoral base Ventral base Snout Fleshy orbit Bony interorbital width Tip of snout to dorsal insertion. . Tip of snout to ventral insertion. Tip of snout to anal insertion Pectoral length Ventral length Counts Gill rakers outer arch, upper limb lower limb Dorsal rays Anal rays Pectoral rays. _ - Ventral rays Total vertebrae total _ Weight. Oso Flaco Creek Feb. 11, 1950 1,160 1,260 205 142 727 111 36 18 81 36 34 202 520 170 78 24 5 19 40 17 15 1% pounds 240 miles off San Pedro Sept. 9, 1950 723 857 124 83 452 71 46 25 20 124 322 558 130 53 21 5 16 39 16 14 8 51 114 CALIFORNIA FISH AND GAME miles west of San Pedro I Lat. 33 c 05' X. Long. 123° 40' W). This fish was caught on a set line during daylight hours at a depth of ahout 15 fathoms on September !>. 1950. Tlic stomach contents of these fishes proved extremely interesting. The specimen taken on February 11 contained 17 small octopi one to three inches in total length ; two rockfish (Sebastodes) eight and three inches long respectively, one hake (Merluccius product us) seven inches long' and two lanternfish (Tarletoribeania crenularis )' each three inches long. The wolffish caught September 9 contained 15 to 20 coelenterates about a half-inch in diameter. The 53-inch fish from Pt. Sal had in its stomach, according to Mr. Taylor who furnished drawings and descrip- tions, "three eels IS inches long and four eels eight inches long" (Oto- phidium?) ; four rockfish (Sebastodes) five to six and one-half inches long; one 2-inch alligatorfish (family Agonidae) ; and 21 squid and octopi up to three inches in length. A number of these fish have been picked up (usually in the surf) throughout the years from San Diego northward to Alaska. Three species have been described from the Pacific Coast ; however, the other two, A. serra and A. aesculapius, are regarded as synonyms of A. borealis. Leuroglossus sti lb i us Gilbert. ( >n the night of February 21, 1950, about 30 of these fish up to seven inches in total length were collected in an experimental mid-depth trawl by the crew of the Division of Fish and Game research vessel Yellowpin. The school from which these fish were collected was quite dense as evi- denced by the "show" on the tape of the recording fathometer. It was spread over a wide area 60 fathoms beneath the surface in 300 to 600 fathoms of water three miles east of Santa Barbara Island. The catch indicated that this school consisted of about a 50-50 mixture of L< ur<>- glossus stilbius and Lampanyctus leucopsarus, a lanternfish. Other lan- ternfish present included Diaphus theta and Tarletoribeania crenularis. The following counts were made on several specimens cleared and stained bv C. R. Clothier: Dorsal rays 9 to 10. anal rays 11 to 12, gill rakers on outer arch 7-9 + 19-21 = = 26-29, vertebrae 39 to 42 (20 to 21 precaudal, and 19 to 21 caudal). Prionotus stephanophrys Lockington. California searobin. Prionotus ruscarius Gilbert and Starks. Searobin. (Figures 55 and 56.) On March 15, 1950, Roy McCoy and George Davis caught one P. stephanophrys on a hand line in 60 fathoms of water while fishing from the boat Ida May about one mile west of the Pt. Fermin buoy. This is the first Prionotus from Southern California taken outside Santa Monica Bay. Some of the measurements in millimeters were : standard length 260, total length 320, head length 90, maxillary 35, first four dorsal spines 30, 38, 40, 38, respectively, and pectoral 106. Gill raker counts on the outer arch were 5 + 17 = 22. Two P. stephanophrys and eight P. ruscarius were caught in gill nets set by the Yellowfin in five fathoms of water at Santa Maria Bay, Lower California (Lat. 24° 47' N, Long. 112° 16' \V) during the night of April 14, 1950. NOTES ON CALIFORNIA MARINE PISHES 115 Figure 55. Searobin, Prionotus ruscarius. Photograph by Al Johns for Vernon M. Haden, San Pedro. Figure 56. Dorsal view of Prionotus ruscarius. Photograph by Al Johns for Vernon M. Haden, San Pedro. Regalecus glesne (Ascanius). Oarfish. (Figures 57 and 58.) On the afternoon of March 29, 1050, a surf fisherman, Thomas De Garmo of Wilmington, noticed a very large and peculiar fish swimming feebly just off a point of rocks at Cabrillo Beach near San Pedro. Several successive waves brought the fish within a few feet of the rocks where Mr. De Garmo was fishing and he jumped into the waist-deep water, grabbed the fish and pulled it ashore. It proved to be an oarfish 10| feet long, 15 inches deep and weighing about 180 pounds. The head was badly cut and battered as if it had been rammed by some vessel or struck by the screw. An old injury to the tail which was healed and pigmented over indicated that more than a foot of that portion of the anatomy was miss- ing. A east was made of this fish by the Scripps Institution of Oceanog- raphy, La Jolla, a short time after it was taken. 116 CALIFORNIA FISH AM) (JA.MK Figure 57. The 1950 oarflsh (Regalecus glesne). Note the missing- portion of the tail and the long' dorsal tin rays in the head region. Photograph by Herb Phillips Photo Salon, San Pedro. Figure 58. The 1901 oarflsh. It was mutilated by the man who first found it on the beach. Photograph courtesy Charles F. Crawford, San Pedro. NOTES ON CALIFORNIA MARINE FISHES 117 This represents the second record of E. glesne from the California coast. The first specimen was washed ashore near Newport Beach (about 20 miles southeast of Cabrillo Beach) in 1901. It was about 20 feet long with an estimated weight of 500 pounds (Figure 58). These fishes, world-wide in distribution, arc not infrequently cast ashore along the Scandinavian coast. There it lias been found that the flesh is very unpalatable. Even dogs will not cat the meat whether offered raw or cooked. The name oarfish is derived from the shape of the two long and blade-like ventral fins. The fish is also known as the king-of-the- herrings because in some localities it was thought to precede or accom- pany the herring shoals. Trichiurus nitens Garman. Pacific Cutlassfish. (Figure 59.) A 30-inch cutlassfish was taken near San Pedro on the morning of June 21, 1950, by the bait boat Peek skippered by Charles Whiteley. It was skeletonized by C. R. Clothier and found to have 148 vertebrae (36 precaudal and 112 caudal). The stomach contained two anchovies, En- graulis m. mordax. Figure 59. Pacific- cutlassfish. Tvichiurus nitens. Photograph by Al Johns for Vernon 1V1. Haden, San Pedro. During the 1930 's considerable numbers of these fish were brought into the San Pedro fresh fish markets where they were sold mostly to Japanese who consider the flesh quite ;s delicacy. On several occasions loads from a few hundred pounds to around a ton were sold for 7 to 10 cents per pound. Old-time fishermen around San Pedro state that about 1915 large cutlassfish weighing several pounds apiece were commonly taken on "rock cod" set lines in some 600 feet of water between San Pedro and Santa Catalina Island. Trachypterus rex-salmonorum Jordan and Gilbert. California Ribbonfish. A 29-inch ribbonfish was caught by the seiner New San Antonio, Frank Iacono, captain, on the night of June 21, 1950. A smaller indi- vidual was caught by another seiner on the same night. Both vessels were fishing several miles off the west end of Santa Catalina Island. Stomach contents of a large specimen included remains of two small rockfish, Sebastodes, one myctophid, Tarletoiibeaniu crenidaris, several small squid and octopi and numerous small crustaceans. (Jill rakers on the outer arch totaled 15 (5 -|- 10). Vertebral counts of two specimens gave a total of 92 each (35 and 37 precaudal, respectively). Lampris regius (Bonnaterre). Opah. (Figure 60.) Several opahs have been landed by sportfishermen during the sum- mer of 1950. The first of these to come to the attention of the laboratory was caught by R. \V. Langenberg, Huntington Park, California, about nine miles off Newport Beach on July 18, 1950. He was fishing for alba- core near Fourteen-mile Bank when the opah struck and was landed after a short battle. This fish weighed 34 pounds 9 ounces and was 30 inches long and 17 inches high. II- CALIFORNIA FISH AND GAME Figure 60. The 24-pound opah, Lampris regius, caught off Monterey on September 25, 1950. Photograph by J. B. Phillips. A second opah was caught in the Los Angeles harbor area a short time later and was estimated to weigh around 80 pounds. The Scripps Institution of Oceanography, La Jolla, made a east of this second fish. On August 2, 1950, a 40-pounder was caught by a Los Angeles fisherman (R. Smith) at almost the same plaee as was the .July 18 specimen. Two of these opahs had identical vertebral counts, 20 precaudal and 24 caudal, while the third had 20 precaudal and 23 caudal. Another was caught in the paddle wheel of a glass-bottom boat at Santa Catalina Island in early September. This fish was gaffed and pulled aboard the boat. Its weight was estimated at 60 to 70 pounds. A fifth opah was caught off Humboldt County in a drag net by a commercial fisherman some time during the summer of 1950. Mr. H. S. Barnes of Fortuna, California, sent a snapshot of this specimen to the laboratory for identification. Further information concerning this cap- ture is not available; however, Mr. Barnes did volunteer information on two other L. regius which were taken by salmon trollers. The first was caught during July, 1945, by Mr. Paul Pellegrini on the troller Sea Gull and the other by Mr. "Bud" Peters on the troller Pandora during 1946 or 1947. Both of these fish weighed 9 or 10 pounds and were caught on salmon spoons in the Eel River Canyon about 16 miles southwest of Humboldt Bar. NOTES ON CALIFORNIA MARINE FISHES 119 Mr. J. B. Phillips, California Division of Fish and Game, wrote as follows concerning still a sixth opah : " [It] was caught about 30 miles west of Monterey on Septem- ber 25, 1950, by A. B. Lindstrom. Mr. Lindstrom was trolling for albacore on his 45-foot fishing boat, the Loyal, when the Opah struck a jig and was hauled in. It was delivered with a load of alba- core to the Regal Seafood Company, Monterey. Mr. Howard Low of that concern turned the specimen over to the Division of Fish and Game. "This specimen was 284 inches total length, and weighed 24^ pounds. The greatest depth of body, exclusive of dorsal and ventral fius, was 15? inches and the greatest thickness of body was 'M, inches." This species is distinguished by the deep, ovate, much compressed body, the dorsal fin which is high and falcate in front, the long ventral fins, the silver spotting on body and the bright red fins. Teeth are absent in the jaws. The color is steely blue to dark bluish gray on the dorsal surface, shading to silver, flushed with light red on the ventral surface. All the fins are brilliant red. The reddish tinge to the ventral surface of the body disappears after the fish has been out of water for a period, and the bril- liant red of the fins fades when the specimen is placed in preservative. The silvery spots are uniformly scattered over the body. The opah is an inhabitant of the open waters, usually of the warmer seas, and is of world-wide distribution though nowhere very common. It attains a length of six feet and a weight of 500 or (i()0 pounds. The food consists of crustaceans, scpiid and small fishes. The name "opah" was given by the natives of the -west coast of Africa who esteem it as a food fish. On the island of Madeira according to Herald (1939) the opah is held in such high regard "that every speci- men taken was required by law to be carried to the governor of the island, without whose license it could not be sold in the market." Along the Pacific Coast, occasional specimens have been taken be- tween Southern California and Alaska. Herald recorded 24 from Califor- nia up to 1939. REFERENCES Barnhart, Percy S. 1936. Marine fishes of Southern California. Berkeley, Univ. Calif. Tress, 200 p., 290 figs. Bolin, Rolf L. 1933. New fish records from Southern California. Copeia, no. 1, p. 35-36. 1939. A review of the myctophid fishes of the Pacific Coast of the United States and of Lower California. Stanford Ichthyological Bull., vol. 1, no. 4, p. 89-156, 29 figs. Fitch, John E. 1950. Life history notes and the early development of the honefish Albula vulpes (Linnaeus). Calif. Fish and Came, vol. 36, no. 1, p. 3-6, 2 figs. Fraser-Brunner, A. 1949. A classification of the fishes of the family Myctophidae. Proc. Zool. Soc, vol. 118, p. 1019-1106, 167 figs., 1 plate. Herald, Earl Stannard 1939. The opah ( Lampris regius) and its occurrence off the California coast. Calif. Fish and Game, vol. 25, no. 3, p. 228-232. lL'll CALIFORNIA PISH AND GAME Hill. Howard Et. 1932. A new record of Ostracion diaphanum Blocfa and Schneider from California. ( lopeia, no. 4, p. 181. Hubbs, Carl L. I!i4-~i. California searobin (Prionotus stephanophrys) , a fish new for the fauna <>f Southern California. Calif. Fish and Game, vol. 31, no. 4, p. 195-200, 1 tig. Huhhs. Carl L., and Clark Hubbs 1H41. Pacific cutlassfish, Trichiurus nitens Garman. Calif. Fish and (lame, vol. 27, no. 1, p. 29-30. Roedel, Phil M., and Howard McCully 1939. Occurrence of the wolf-fish Alepisaurus aesculapius (Bean) in Southern California. Calif. Fish and Game, vol. -~> , no. 1. p. 35-37. LAMPARA NET PULLING GURDIES 1 By J. B. Phillips Bureau of Marine Fisheries California Division of Fish and Game During' the past three and one-half years the small lampara net boats at Santa Cruz have been operating with half as many men in a crew because of the installation of net-pulling gurdies. hi the spring of 1947, John Ceechini, captain of the lampara boat Anna Alma, hit upon the idea of mounting two modified shark gill net gurdies aboard his boat, each to pull in a wing of the net. This innovation proved successful and soon other Santa Cruz boats using lamparas installed similar gurdies. The basic part of these net-pullers is the rear axle assembly from an old ear placed upright on the deck with a wheel six to eight inches thick and about 16 inches in diameter mounted to the upper or free end (Figure 61) . The edge of the wheel is concave like a sheave and lined with rubber to accommodate and grip the net. Power to turn the axle and wheel is applied to the lower end of the axle through a power takeoff from the main engine. The net-pulling gurdies are not stock models but are made 1 Submitted for publication September, 1950. Figure 61. The two capstanlike net pullers aboard the 35- foot Santa Cruz fishing boat Sal Boy. Photograph by J. B. Phillips, September 18, 1950. (121) 122 CALIFORNIA FISH AND GAME Figure 62. Unloading sardines from the barge of the lampara boat Sal, Boy, at a Moss Landing cannery. The fifth man of the crew, not in photo, is operating a hoist- ing winch. Note the net-pullers mounted on the deck of the powerboat. Photograph by J. B. Phillips, September 18, 1950. to order by a machine shop in Santa Cruz and are installed by the crews of the boats. The average cost of the parts and other modifications neces- sary on each boat is about $500, exclusive of installation. Originally, Mr. Ceechini tried the two net-pulling heads in a vertical position, similar to rope-pulling gurdies, but this did not prove nearly as satisfactory as the present arrangement. The boats on which net-pullers have been installed vary from 29 to 40 feet in length. Their engines range from 90 to 165 horsepower ; most of them are gasoline-powered. Except for one vessel which is constructed to carry about 25 tons in the hold, these boats tow barges that carry 20 to 40 tons of fish. Most of the barges are war-surplus steel lifeboats although one is a plywood landing barge. The lampara nets are 120 to 172 fathoms in length along the cork line and 20 to 25 fathoms deep at the bag. The cost of the materials is $1,000 to $1,500. One of the larger lampara nets used by Santa Cruz fishermen is 172 fathoms around the cork line. Each wing is 65 fathoms long and the bag is 42 fathoms long. The depth of the bag is 25 fathoms. The tapered wings are composed of eight-inch mesh (stretched), nine-thread webbing. The bag is made up of seven-eighths-inch webbing, six-thread. In the central section of the bag, next to the wings, is a square section of four-inch mesh, nine-thread, called the apron. In the central portion of the bag, next to the cork line, is another square section of webbing of one-inch mesh, nine- thread. This latter section of webbing, sometimes called the "sack," is the portion into which the catch is concentrated for brailing. LAMPARA NET-PULLING GURDIES 123 Nearly all boats have an extra lampara, in case the net in use is badly damaged and cannot be repaired in time for the following night's fishing. When fishing is good the nets are tanned every two weeks. Only four or five men, including the captain, compose a crew of a boat equipped with the two net pullers. Before the net pullers were installed, eight to ten men were needed. The crews work on a share basis as do the purse seine crews at Monterey. Because of the smaller investment in boat and net, only two shares are reserved for them and each of the crew receives one share. With a five-man crew this makes a total of seven shares by which the proceeds of the catch are divided. With larger purse seine boats, the number of shares will total about 20. When a set is made with a lampara net, it takes about 15 minutes to pull in the wings with the aid of the net-puller. Since the wings taper to an apex at the ends and are of eight-inch mesh, they pull through the water readily. By the time the wings are in, the lead line, which is shorter than the cork line, is also in, thus cutting off the escape of the fish below. The bag portion of the net in which the fish are trapped is pulled in by hand until the fish are concentrated in the sack, from which they are brailed. If no fish are caught, it takes about one-half hour to set and haul the net. For 10 tons of sardines it will take about an hour to haul the net and load the catch ; for 30 tons it will take about two and one-half hours. None of the few lampara boats at Monterey has these double net- pnllers installed (September, 1950). At Santa Cruz, 11 lampara boats had net-pullers in 1950. In 1919, three boats now fishing with other gear were using a lampara with the aid of the mechanical net-pullers. THE INTRODUCTION OF KOKANEE RED SALMON (ONCORHYNCHUS NERKA KENNERLYI) INTO LAKE TAHOE, CALIFORNIA AND NEVADA 1 By J. C. FBASEB and A. F. POLLITT Bureau of Fish Conservation, California Division of Fish and Game Ever since Lake Tahoe's vast area ceased to produce the once fabulous population of cutthroat trout, fisheries workers have sought to re-establish a satisfactory game fish population. At the present time this interstate water provides some fishing for the introduced lake (mackinaw) and rainbow fronts. Neither species has lived up to its original expectations as regards production of angling in keeping with the lake's size and recreational importance. Reduction in spawning areas for rainbow through summer use of water from tributary streams is probably one of the factors limiting the production of that species, and shortage of forage fish in the open and deeper waters of the lake may be a limitation on the production of lake front. 1 n recent years, attention has been given to the kokanee, a landlocked form of the red salmon, native to waters of the Pacific northwest, which was first introduced into California waters on an experimental basis in 1941. The decision to introduce the kokanee into such an important body of water as Lake Tahoe was based on several factors, after the habits and requirements of the fish had been studied in other waters. Briefly, these factors are as follows: (1) The kokanee is an open-water lake fish and a feeder on minute plants and animals. Thus; it does not compete seriously with shoal or bottom feeding types of game fish for food, nor is it car- nivorous in relation to other species of fish. (2) It is a desirable game fish and has excellent eating qualities. (3) It is a good reproducer, utilizing both gravelly shore areas and tributary streams for spawning. The abundance of good shore spawning areas in Lake Tahoe should be a con- tributing factor to satisfactory population increase. (4) The kokanee prefers cool water and Lake Tahoe's temperatures are very suitable in this respect. (5) Indications are that the kokanee itself may provide a source of food for other game fish if it becomes sufficiently abundant. In summary, it may be said that the kokanee is not a predator, that it appears to be well suited to the environment of Lake Tahoe, and that there is reason to hope it will become sufficiently abundant to prove a real asset to the lake's fishery. Kokanee were first introduced into Lake Tahoe in 1944 through accidental escapement from the Tahoe Hatchery. Returning spawners from this escapement appeared in the hatchery outflow stream in 1946 ; these fish averaged 14| inches in length. 1 Submitted for publication October, 1950. ( 125 ) 126 CALIFORNIA PISH AND GAME Tlic first phase of the program to establish a large population of kokanee started in 1!)4!», with the planting of 90,000 fingerlings in three tributary streams on the California side of Lake Tahoe. It should be noted at this point that the Lake Tahoe kokanee introduction program received the full sanction and support of the Nevada Pish and Game Commission before its inception. 2 In 1950 a total of 613,475 fingerling kokanee was planted directly in the lake and in suitable tributary streams in Nevada and California. These fish were hatched from eggs obtained by California from the Idaho Department of Fish and Game. Approximately 338,900 of these salmon were raised in the Idlewild Hatchery of AVashoe County, located in Reno, Nevada. The remainder- were raised in the Basin Creek and Tahoe State Fish Hatcheries, in California. Planting in the lake itself was accomplished by power boat and barge. A regular 150-gallon fish planting tank was mounted on a barge and the fish thus transported were planted in suitable shore spawning areas along both the California and Nevada shore lines. Planting in these shore spawning areas was made to take advantage of the homing instinct of the kokanee, so that maximum utilization of available spawning areas could be obtained. These shore planting areas were predetermined on the basis of surveys made by personnel of both the Nevada and California Fish and Game Divisions. Many areas were not accessible bv land routes 2 The authors wish to acknowledge the work done by Messrs. S. S. Wheeler, Direc- tor of the Nevada Fish and Game Commission during the program's inception ; Thomas J. Trelease, Nevada Fish and Game biologist ; and other personnel of the State of Nevada Fish and Game Commission, who played an important role in all phases of the program. Figure 63. View of 150-gallon planting tank mounted on barge used in distribution of kokanee to snowbound shore areas of Lake Tahoe in April, 1950. INTRODUCTION OF KOKANEE INTO LAKE TAHOE 127 during April, May, and early June, when the plantings were made, be- cause of deep snows or lack of roads. Thus, the use of this barge proved to be a very satisfactory method of transportation whereby maximum distribution of the fish could be obtained in suitable areas. All of the tributary streams to Lake Tahoe suitable for spawning were stocked from trucks. This entire stocking program is directed at producing an initial population, which in subsequent years should gradually build itself up to a satisfactory level through natural reproduction. It is tentatively planned to continue this artificial stocking program through 1953. Stream improvement work in the way of barrier removals, stream flow mainte- nance, and spawning area improvement is being carried on in streams tributary to Lake Tahoe to increase the success of natural reproduction. Careful follow-up studies on the spawning runs and success of spawning when this activity starts are also planned. Although the kokanee has excellent possibilities for improvement of the Lake Tahoe fishery, it should not prematurely be considered as a panacea for all of the lake's problems. In the few other waters in Cali- fornia in which the kokanee has been introduced (Curtis and Fraser, 1948) its success has not been uniformly good: growth has been limited in Echo Lake and survival to maturity low in some years in the other waters. Its ability to improve the fishery picture of Lake Tahoe will depend largely upon its spawning success in the years to come. REFERENCE Curtis, Brian, and J. C. Fraser 1948. Kokanee in California. Calif. Fish and Game, vol. 34, no. 8, p. 111-114, 1 fig. THE EMBRYONIC AND EARLY LARVAL STAGES OF THE TUI CHUB, SIPHATELES BICOLOR (GIRARD), FROM EAGLE LAKE, CALIFORNIA 1 By Robebt R. IIarby Stanford University INTRODUCTION The complete early development lias not been described for any native western North America cyprinid. The postembryonic development of one species, the venns roach, Hesperoleucus venilstus Snyder, has been discussed in detail by Fry (1936), but its embryonic development is completely unknown . The present study on the tni chub, Siphateles bicolor (Girard), was made by the writer while in the employ of the California Division of Fish and flame. It was carried out at the suggestion of Mr. Harry A. Hanson of the Division and forms an integral part of an investigation into the entire life cycle of the species in Eagle Lake, Lassen County, being conducted by Mr. J. Bruce Kimsey, also of the Division of Fish and Came. Fertilized eggs of the tui chub were obtained at Eagle Lake by Mr. Ivimsey and the writer and their development studied by the latter from 70 hours after fertilization to 12 hours after hatching. It is unfortunate that circumstances caused the development of the eggs under conditions that did not lead to unquestionably normal results and that there was no chance to repeat the work under more normal conditions. However, since there is so little recorded on the early development of fishes, the publication of the present study, even if incomplete, seemed worthwhile. METHODS Ripe adults were caught in a gill net on the western side of Eagle Lake near Webb's resort (formerly Spaulding's) over their spawning grounds, which were approximately six feet in depth. The females were stripped into a bowl containing plants and the eggs were artificially inseminated at 8 a.m. on June 2-1, 1949. Approximately 20,000 eggs were obtained and immediately transported to the Lake Almanor State Fish Hatchery on Clear Creek, Lassen County. They arrived at noon the same day and were placed in quart jars partly submerged in a trout hatching trough. The eggs were kept in the highly mineralized Eagle Lake water at all times. The water was partially changed at frequent intervals and most of the eggs were kept at an even temperature of 45 degrees F., approximately 20 decrees below that normal for the development of Siphateles eggs in Eagle Lake. 1 Submitted for publication October, 1950. ( 129 ) 130 CALIFORNIA FISH AND GAME All eggs developed normally for the first 100 hours, forming the blastodermal cap and the segmentation cavity. After the latter stage the eggs at 45 degrees either remained dormant or continued growth with irregular cell development. Some of the eggs clumped together in large masses and these eggs formed the blastodermal cap, but developed abnor- mally thereafter. The yolk became granular and shrunken, and after about TOO hours these eggs also seemed to become dormant, without fur- ther organized development. However, they did not die or appear to be more susceptible to fungus than the properly developing eggs. Three days after stripping 100 eggs were removed and allowed to stay at room temperature, which varied from 34 degrees to 84 degrees P. These eggs developed rapidly and appeared to be almost fully formed within six days. At this time most of the eggs died from fungus. The remaining embryos continued to develop, and formed the pigment pat- tern characteristic of this species. It is possible that the embryos were so weakened by abnormal conditions for development that they were unable to break out of the eggs at the proper time. In the following description of embryonic development the eggs at 45 degrees are used for the first 100 hours. The remainder of the description is compiled from embryos kept at room temperature. Only one larva hatched and the description of the early larval stages is from this specimen. DESCRIPTION OF EGGS The freshly stripped eggs of Siphateles are translucent, yellowish, spherical, adhesive, and rather large for cyprinid eggs, measuring 1.8-2.0 mm. in diameter. Their specific gravity is considerably more than that of fresh water and the free eggs sink quickly to the bottom. The membrane is thick and tough but fairly smooth. The surface is covered with minute crenulations, which at first are hardly visible under 160x power, and which become covered with the floating matter in the water as development progresses. The yolk is filled with numerous oil globules and appears to be separated into small cells, but is so opaque that it is impossible to determine whether or not the divisions are limited to the surface. The eggs are emitted as a sticky, fluid mass and adhere to each other or other objects soon after coming in contact with fresh water. This adhesive character is soon lost. The membrane becomes flattened over a wide surface wherever the eggs come in contact with each other. EARLY EMBRYONIC DEVELOPMENT By 70 hours the fully developed blastodermal cap (Figure 64, A) has become a symmetrical dome. It is very large and its outer surface forms a gentle curve almost continuous with the outline of the yolk. Its irregular inner surface pushes into the yoke. At this time the cells are so small as to be indistinguishable. During all stages of development the perivitelline space is small. The segmentation cavity (Figure 64, B), partly developed beneath the central area of the blastodermal cap, is formed by the thinning of the central blastodermal wall. This cavity could be distinguished by looking down on the upper surface of the blastoderm in the early stages (Figure 64, C). EMBRYONIC AND LARVAL STAGES OF THE TFI (HUB 131 At about 100 hours the segmentation cavity is narrower and slightly eccentric. This is the first indication of the main axis of the future em- bryo; the thicker area marks tbe posterior pole. Continued growth and development of the segmentation cavity causes a thinning of the central portion of the blastodermal cap and a V- ****" "it ' ' Ijlj. - ' ■"«*. * ~v*V - ™fr ' '13JH ' {'& l j '- W*^;ii .» >m&ms Figure 64. Development of Siphateles bicolor (Girard). A. 70 hours after fertilization. B. 85 hours. C. 100 hours. D. 120 hours. E. 136 hours. F. 152 hours. G. 170 hours. H. Larva about 6 hours after hatching. 182 CALIFORNIA PISH AND GAME thickening of the peripheral germ ring, which is very difficult to dis- tinguish and appears as a broad, slightly darker ring surrounding a more translucent area. From the time of its origin until the closure of the blastopore it marks the advance of the blastoderm over the yolk sphere. The embryonic shield is fairly narrow and somewhat wedge-shaped. During the formation of the embryonic axis the blastoderm covers half of the yolk sphere at about 120 hours (Figure 64, D). At about the same time that the germ ring forms an equatorial belt, Kupffer's vesicle appears imbedded in the yolk at the posterior end of the embryo and metameric segmentation is detected at the middle of the body. The notochord also becomes apparent. LATE EMBRYONIC DEVELOPMENT Near the time of the closure of the blastopore at 136-140 hours (Fig- ure 64, E and F) the eyes become visible. Metameric segmentation is well developed caudally and the heart begins to pulsate below the middle of the left eye (viewed from the dorsal aspect). Immediately behind the eyes the auditory capsules are barely visible as small oval vesicles. Kupffer's vesicle now appears to be obsolete. At 170 hours (Figure 64, G) the blastopore is closed and the head as a whole has increased markedly in size. The pupils and lenses in the eyes are visible and the otoliths are formed. The tail twitches from side to side at frequent intervals and passes over the snout and eyes. The con- tinuous fin fold is clearly visible. About the ninth day pigment begins to appear in the form of several rows of conspicuous melanophores on the dorsal side, particularly on the head. The eyes are heavily pigmented. The extent of pigmentation in- creases during the remainder of embryonic development. The yolk becomes reduced to less than half its original size. EARLY LARVAL DEVELOPMENT After hatching, which took place during the night of the twelfth day, the larva was exceptionally active and was able to swim rapidly and effectively (Figure 64, H). The yolk was almost completely absorbed. The auditory capsules were enlarged and the cells of the notochord could be seen along its entire length. The tail had begun to develop rays (cera- totrichia) and to change shape. Chromatophores were concentrated along the ventral midline of the body, exclusive of the gut. Two irregular longitudinal rows of large melanophores extended along each side of the dorsal midline. A large triangular blotch of ept h to bottom of keel amidship 14 feet 7 inches Mean draft, full load 11 feet 3| inches Light displacement tonnage 417.53 Gross tonnage 272 Net tonnage 112 1 Submitted for publication November, 1950. ( 133 ) 134 CALIFORNIA FISH AND GAME I M J THE M.V. YELLOWFIN 135 Main propulsion twin 320 hp, 325 Kl'M single act- ing, four cycle, solid injection, six cylinder Atlas Imperial mode] ('» HM 1558 diesel engines. Auxiliary power two Hercules model DJXC 3Jx4| diesel engines, each driving a 20 KW 125 volt DC generator. Cruising speed 10 knots Maximum speed 11.2 knots Extensive repair and conversion were necessary to adapt the vessel for scientific work. Plains were drawn up and work was supervised by G. Bruce Newby, Naval Architect. Repair and conversion was accomplished at the yard of the Long' Beach Marine Repair Company, Long Beach. It was attempted to make the vessel as versatile as possible, from a fishing point of view, without a major modification of the hull. However, the N. B. Scofield, which was constructed especially for marine fisheries research was already well adapted to tuna and trawl investigations, so emphasis in conversion of the Yellowfin was placed upon utilization in high seas sardine and mackerel work, together with oceanographic observations. In the conversion, additional fuel and water tanks were installed, together with additional refrigeration space, to create total capacities as follows : Dieselfuel 20.000 gallons Fresh water 2,500 gallons Cruising radius 6,000 miles at 10 knots Refrigeration, food, frozen 127 cubic feet Refrigeration, food, chilled 100 cubic feet Refrigeration, specimens, frozen 30 cubic feet Stateroom accommodations are provided for 13 persons as follows: Master, fisheries vessel 1 Motor vessel engineman 1 Netman and boatswain 1 Assistant motor vessel engineman 1 Radiotelegraph operator and assistant engineman 1 Ship's cook 1 Deckhand __. .__ 4 Scientific personnel 3 In addition, emergency accommodations for four persons are installed in the forecastle. Certain equipment was installed to aid in navigation of the vessel, as follows : Radio Transmitting side : radiotelephone 500-100 watts power, 7 crystal controlled channels. CW section power output ISO watts; crystal controlled channels. Receiver side: re- ceiving coils, reception 30 megacycles to ISO kilocycles. Radar Mariners pathfinder, Raytheon model 1107, with wheelhouse- mounted plan position indicator. Maximum range 40 miles, with 20, 8, 4, 2, and 1 mile scales. Automatic pilot Sperry magnetic compass pilot, in wheelhouse, with Sperry electric nonfollowup controller and rudder angle indicator moulded on top of house for maneuvering. Echo sounding Submarine Signal model 710-M 20 KC indicator, maximum depth 2,500 fathoms. Remote control Engine speed may be controlled from both wheelhouse and top of house through a hydraulic throttle system. 136 CALIFORNIA FISH AM) GAME THE M.V. YELLOWFIN 137 i o < • *M0i»808»T 1 o Q -3 OJ - H i:js CALIFORNIA FISH AND GAME BRIDGE DECK Figure 68. Bridge deck, M. V. Yellowfin PLATFORM DECK Figure 69. Platform deck, M. V. Yellowfin THE M.V. YELLOWFIN 139 Certain special equipment was installed to aid in locating schools of fish : Echo ranging Model WEA-2a sonar, approximately 23 KC, maximum range 5,000 yards, with neon-tube indicator and Sangamo recorder wheelhouse-mounted. Echo sounding Submarine Signal Co. model 1215A recording fathometer, maximum depth 500 fathoms, with 500-foot scale, and vari- able chart feed rate. Frequency 40 KC. Other equipment was installed to aid in fishing operations, and in scientific observations : Winch Northern Dragger model 200-D, 2-drum trawling winch, with uill net gurdy and longline gnrdy attachments. Driven by 30 hp electric motor through a hydraulic torque con- verter. May be utilized for plankton tows and Xansen bottle casts as well as trawling and other fishing operations. Winch __Standard high speed bathythermograph winch, capacity 2.000 feet % 2 -inch cable. Bait tank Portable, 6Vx5^'x4^', supplied with salt water by 2-inch vertical bait pump. Capacity about 40 scoops of bait. Rollers Side roller for hauling gill nets and bow roller for riding war]) when gill nets are set. The Yellowfin was placed in service September 20, 1949. To De- cember 1, 1950, she had completed lb' cruises in waters from Northern California to Cape San Lucas, Baja California. The vessel has been uti- lized for work on the following problems : 1. Development of rapid methods for locating and identifying pelagic schools of fish. 2. Measurement of environmental conditions where sardines (Sar- dinops caerulea) are found. 3. Measurement of the relative abundance of the sardine 1950 year class. ; 4. Collection of jack and Pacific mackerel (Tra churns symmetricus, Pneumatorphorus diego) for population studies. 5. Collection of material for an analysis of food of jack mackerel. b. Tagging sand and kelp bass (Paralabrax nebulifer, P. clathratus) . The vessel has proved quite suitable for the uses to which she has been put, and is a valuable addition to the pelagic fishery research pro- gram of the Division of Fish and Game. EFFECTS OF HUNTING PRESSURE AND GAME FARM STOCKING ON PHEASANT POPULA- TIONS IN THE SACRAMENTO VALLEY, CALIFORNIA, 1946-1949 1 By Harold T. Harper, Chester M. Hart and Dale E. Shaffer Bureau of Game Conservation, California Division of Fish and Game INTRODUCTION Most of California's pheasant populations (Phasianus colchicus) are found in the Sacramento Valley, and consequently the heaviest hunt- ing pressure on these birds occurs here. To supplement the breeding- stock and the kill of pheasants, game farm stock has been released in increasing numbers each year. In order to study the effects of heavy hunting pressure and game farm stocking, two pheasant study areas were established in typical Sacramento Valley pheasant habitat. From this study, information was gathered that will be valuable in the management of the ring-necked pheasant in California. THE STUDY AREAS These two areas, the Sartain and McManus, were selected as they were similar in size, readily accessible to hunters, and planted to the same crops. Both were located in the rice growing section of the Sacramento Valley. Annual precipitation averages 24 inches, with little or no rain- fall during the summer ; winters are mild and snow is unusual. The Sartain study area was a corporation ranch located 12 miles west of Gridley in Colusa County, under the direction of Mr. Terrill Sartain. It contained 6,920 acres composed of rice, barley, and pasture or waste land interspersed with numerous tule-filled sloughs and canals. The McManus area, in Glenn County, consisted of a group of ranches owned by nine individuals. This area included 7,800 acres of rice, fallow rice, barley, and pasture or waste land, again interspersed with many tule-filled sloughs and canals. In 1949, 130 acres were planted to milo maize. The areas were only three and one-half miles apart, but the land from the north boundary of Sartain 's to the south boundary of the McManus area was dry, unirrigated grain land with a comparatively light pheasant population. This acted as a barrier to the movements of birds between the two study areas. Table 1 gives the acreages of crops grown and Figure 70 shows the location of each area. 1 Submitted for publication June, 1950. Federal Aid in Wildlife Restoration Act, Project California 22-R. The authors wish to acknowledge contributions to this study made by Project 22-R Assistants Jack Hiehle, John P. Davis and Fred Jones, and former 22-R Project Leaders Carol M. Ferrel and Howard Twining ; also, to Wallace Mac- gregor, John Cowan and Gordon Bolander, former Project 22-R Assistants. Appreciation is expressed to the numerous bureau personnel who served as hunter interview officers during the years of study. (141) 2—39247 142 CALIFORNIA FISH AXD GAME Figure 70. Location of the Sartain and McManus study areas and the area censused by airplane in the Sacramento Valley PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY TABLE 1 Crop Acreages, 1947-1949 143 Rice Fallow rice Barley Pasture Milo maize Total Sartain 1947 3,160 2,535 2,535 3,360 2,722 2,560 80 603 455 3,720 4,155 4.155 3,560 3,966 4,225 40 230 230 800 509 430 130 6,920 1948..- 6,920 1949 6,920 McManus 1947 7,800 1948 1949 7,800 7,800 During- the hunting season both areas contained plowed and leveled ground where the barley stubble had been turned under in prepration of the soil for the next season's crop production. The rice was harvested before the hunting season but the stubble remained and provided both food and cover. Game farm birds, both cocks and hens, were released on the Sartain area from 1946 through 1949. Various age groups were liberated at intervals before the hunting season. In 1949, a sample of the wild resi- dent population on Sartain 's was trapped and banded, and some addi- tional wild-trapped cocks were transplanted from local refuges. The McManus was used as a comparative check area, and no pheasants were liberated there during the years of the study. Preseason and postseason sex ratio counts were made on both areas from 1947 through 1949. This was done by hiking through the areas, counting cocks and hens flushed. HUNTING SEASON CHECKS The dates of the hunting season each vear were as follows: 1946, December 6-15 ; 1947, November 21-30 ; 1948, November 19-28 ; and 1949, November 18-27, all dates inclusive. Daily shooting time started at 10 a.m. in 1946 and at 8 a.m. in 1947, 1948, and 1949. Shooting was stopped at one-half hour after sunset from 1946 through 1948 and at sunset in 1949. A daily bag limit of two male birds and a seasonal limit of 10 was in force during each of the four years. In 1946, the check on the Sartain area was conducted with the use of two road blocks during the first three days and last two days of the season. During the intervening five days an attempt was made to contact hunters in the field. This method proved unsatisfactory and in following years a system giving a more complete check was used. No check was made on the McManus area in 1946. In 1947 and 1948, roads leading from both areas were either blocked or had checking stations on them. In 1949, one road on the McManus and two roads on the Sartain area were not blocked as these received very little traffic and the loss of hunter information was considered to be insignificant. In 1947, a 1,680 acre tract on the Sartain ranch was restricted to hunting by Mr. Sartain 's numerous personal friends. After the sixth day this was reduced to 260 acres immediately surrounding ranch head- quarters. In 1948 and 1949 the restricted area consisted of 1,280 acres. Hunting on this section of the ranch was moderate. Permission to hunt 144 CALIFORNIA FISH AND GAME on unrestricted land was granted by Mr. Sartain in 1946 and 1947. In 1947 and 1948 the California Division of Fish and Game posted the land with signs advising- hunters that the ranch was open to hunting and that it was an experimental pheasant study area. Written permits to hunt were issued by the Division in 1948. The Sartain area was operated under both the cooperative hunting area plan and the pheasant planting pol- icy 1 in 1949. A 1,680-acre block was placed under the pheasant planting policy and liberations of both game farm and wild-trapped birds were made there. Hunting on this area was free. The remaining 5,240 acres of the study area was operated under the cooperative hunting area plan and a fee of $2 per day per hunter was charged. The Division limited the number of hunters to one per five acres at any one time, but not once during the season was the quota filled. Mr. Sartain was responsible for issuing permits for the cooperative hunting area, while the Division of Fish and Game issued permits for the pheasant planting area. The McManus area was not posted with Division signs and permits to hunt were granted solely by the landowners. A commercial hunting club containing 960 acres was located inside the west boundary in 1948 and 1949. In 1948 and 1949, a trespass fee was charged on approximately 1,140 acres hung inside the east border. Hunting on these two areas was only moderate and was comparable to pressure on the restricted tract on the Sartain ranch. An airplane census of hunter's cars was made during the 1947, 1948, and 1949 seasons. Both study areas were censused and a count was made which included 269 square miles of pheasant habitat in the Sacramento Valley. Data procured during the four-year hunting season check included : information regarding the area, number of hunters, number of automo- biles, county of hunter's residence, number of hours hunted foi 4 day interviewed, total number of days hunted, number of birds bagged, kill of game farm birds, kill of transplanted wild birds, age ratios of birds killed, and samples of pheasant weights. HUNTING SEASON RESULTS Airplane Census of Cars Cars were counted by airplane on the first three mornings of the 1947 and 1948 seasons from 8.30 a.m. to 10 a.m., and from 9.30 a.m. to 11 a.m. in 1949. The area covered, by flying parallel courses, was bounded on the south by the Gridley-Colusa Road, on the west by the Sacramento River, on the east by Highway 99E, and on the north by a line from the out- skirts of Chico west to the Sacramento River (Figure 70). These bound- aries enclosed approximately 269 square miles. The same area was cen- sused in 1947, 1948, and 1949. All cars, except farm trucks, whether on or off the road, were counted. Results of this census are included in Table 2. The figures for total cars counted indicate that in 1948 there was an increase in hunting in the Sacramento Valley over that in 1947. This was followed by a nearly proportionate decrease in 1949. 1 Under this policy state reared pheasants are released on land which is open to free public hunting with verbal or written permission from the landowner. PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY 145 TABLE 2 Composite Census of Hunters in 269 Square Miles of the Sacramento Valley, 1947-1949 Total cars 1 Average number hunters/car 2 Total hunters Cars per square mile Hunters per square mile 1st day 1947.. 1,713 2,198 1,478 1,349 2,056 1,416 1.149 1,507 1,286 2.6 2.6 2.6 2.6 2.7 2.7 2.5 2.7 2.6 4,437 5,649 3,843 3,507 5,551 3,823 2,895 4,039 3,344 6.4 8.2 5.5 5.0 7.6 5.2 4.3 5.6 4.8 16.5 1948.. 21.0 1949 14.3 2ddav 1947 13.0 1948.. 20.6 1949.. 14.2 3d day 1947 10.8 1948 15.0 1949 12.4 1 Does not include cars counted on Sartain and McManus areas. 2 Computed by averaging the number of hunters per car for both Sartain and McManus areas and applying to the entire region. TABLE 3 Percent of Daily Totals of Cars That Were Counted by Airplane Sartain McManus 1948 1949* 1948 1949 1st day _ _ ___ _ 74.5 76.2 67.6 112.0 120.0 84.1 46.1 50.2 46.8 45.2 2d day 43.0 3d day. _ . 40.3 * These high percentages result from the fact that all cars parked on the boundary roads were counted. Many of these hunters were hunting off the study area and their cars were not tabulated at checking stations. Nearly all of this land was closed to hunting previous to 1949. The constancy of the average number of hunters per car from year to year suggests that in future years hunter censuses of any large area in the Sacramento Valley can be made through car counts by airplane. A comparison of checking station counts with airplane counts is shown in Table 3. From these comparisons it is evident that airplane censuses are not accurate for small areas. Hunters move from one site to another during the day, and for a small area too low a count will result from a flight of short duration. .Additional errors are caused by the impossibility of determining accurately from the air where a hunter is hunting from the position of his parked car. It is further evident that such counts can- not be accurate on areas where pheasant hunting is light, for too high a percentage of cars counted would belong to nonhunters. Hunting Pressure The basic information acquired from each year's check is given in Table 4. The number of hunters on each area varied from year to year. In 1948 considerable publicity was given to the areas by San Francisco and Los Angeles newspapers. This brought about a decided increase of hunters which was somewhat greater on the Sartain than on the McManus 146 CALIFORNIA FISH AND GAME TABLE 4 Composite Summary of Hunter Checks, 1947-1949 Area Cars checked Hunters checked Total kiU Hunters per car Birds per hunter Sartain 1947 1,029 2,225 1,175 906 1,686 1,630 2,592 5,836 2,848 2,375 4,223 4,174 1,023 3,230 1,697 958 2,656 1,420 2.5 2.6 2.4 2.6 2.5 2.6 39 1948 55 1949 ._ 60 McManus 1947 0.40 1948 0.63 1949 34 area. In 1949 the fee charged on the Sartain Cooperative Hunting Area turned some hunters away. Five other cooperative hunting areas, oper- ated on a nonf ee basis and located closer to large cities, attracted hunters who formerly went to the Sartain ranch (Harper et al., 1950). There was only a slight decrease in numbers of hunters from 1948 to 1949 on the McManus study area. Daily and seasonal numbers of hunters per 1,000 acres are given in Table 5. The general increase in the number of hunters on both study areas in 1948 was a reflection of an over-all increase in hunting through- out the Sacramento Valley. TABLE 5 Hunters Per 1,000 Acres Per Day, 1947-1949 Area Day of Season Season 1 2 3 4 5 6 7 8 9 10 total Sartain 1947 112 229 123 85 149 170 84 207 100 63 134 176 59 136 73 67 102 101 12 30 14 7 24 12 13 34 17 9 17 16 11 28 16 8 17 6 14 27 16 17 16 14 12 27 13 5 16 8 30 67 18 20 31 16 27 58 22 25 35 17 374 1948 843 1949 412 McManus 1947 306 1948.. 541 1949.. 536 TABLE 6 Average Hours Hunt Areas, 1947 ed Daily Per Hunter < -1949 (Season Total) >n Study Area 1947 1948 1949 Sartain 3.2 3.5 3.4 4.2 McManus 3.8 The average number of hours hunted daily by each hunter increased each year as is shown in Table 6. There is no single explanation for the increase in time spent in hunting each year. The large increase noted in 1949 on the Sartain ranch was probably stimulated by the $2 fee. Hunt- ers had an incentive to stay in the field longer when they had to pay this fee. PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY 147 Two methods of expressing hunting pressure are gun hours per 1,000 acres and gun hours per cock in the field. The latter is calculated by dividing total gun hours by the preseason cock population. It is a measure of hunting pressure exerted on the bird. Table 7 shows the two. TABLE 7 Measures of Hunting Pressure Sartain McManus Gun hours per 1,000 acres Gun hours per cock in field Gun hours per 1,000 acres Gun hours per cock in field 1947 1948 1,198 2,949 1,722 5.3 4.2 5.0 1,835 2,009 3~6 1949 6.8 35 30 25 o 20 15 10 SUMMARIZATION 1ST 3 5 WEEK LAST 2 TOTAL/IOOO DAYS DAYS DAYS ACRES 1947 69% 16% 15% 1,198 1948 68% 17% 15% 2,949 1949 76% 15% 9% 1,729 1947 1948 1949 fc^-- __-?> I 234567 89 10 DAY OF SEASON Figure 71. Daily percentage of total gun hours on the Sartain Ranch 30 25 .20 35 ■15 .10 148 CALIFORNIA FISH AND GAME 35 30 25 20 UJ o DC UJ Q- 15 35 30 SUMMARIZATION 1ST 3 5WEEK LAST 2 TOTAL/ 1000 DAYS DAYS DAYS ACRES 1948 72% 15% 13% 1,835 1949 84% 10% 6% 2,009 10 1948 1949 8 20 15 . 10 . 5 10 I 2 3 4 5 6 7 DAY OF SEASON Figure 72. Daily percentage of total gun hours on the McManus area Daily percentage of gun hours is shown for the Sartain area in Fig- ure 71 and for the McManus area in Figure 72. Distribution of hunting- pressure throughout the season has been similar each year with the heaviest pressure being exerted during the first three days. Week days have had light pressure followed by an increase on the last two days. Residence of Hunters In order to evaluate the importance of pheasant hunting in the Sac- ramento Valley to the State as a whole, the region of residence of hunters was recorded (Table 8). As considerable publicity had been given to the Sartain ranch, it received greater nonlocal pressure than adjacent areas. In each year of the study the bulk of the hunting during the entire season was done by residents of the San Francisco Bay area. Hunting by local people was second in importance, while relatively small numbers of hunters were from other regions. PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY 149 (0 c o V) re a> CO CD rr -a c re oo 01 o C 0> T3 00 HI in 9) CO *o _o 'en v DC JQ C I re -u E V o S- > > d T3 CM "^ --i CO 00 (MONONiO faC Oa Oa b- CO CO CO CD CI -f "3 CD a O t- NCOWHON «*1 03 oa co co co co oo CM "^ Oi •*0C Oi CO CM t-h O CO ca »C CO *T3 fl CD CD oo io cm us oa io •* CD * Oi CD -^ i— t CO CO O iO CM «-H oj (X| b- COO CO CM CO H oa CO b* CM t-H TJH 00 CD rH Oft O CO COO Tt< "> 03 OO oa O CO iOO OO i- i 00 oa b- "* CM 00 o 1— < p t- ** oa i— i oa CO Oa QO CO CO Th oa oa b- cd co co oa CO >» T3 CO CO CO OO lO O OC' »-H «o -— * bfl oa oa oa co »c co oa -f CM '3 CD P, o b~ »0 oa co -^O oa oa O N lO CO "O N lO CM i O i , >> . !'5b ; JjS i BayR ornia.. alley__ nto Va cisco Calif uin V crame ' g a a* p3 : 2 & g r -° : 13^^^ fe S3 o a 3 a-dja O ccj O c3 ** -*■* h^coojgoOO "3 M - CD - CO Si e« t72 * CD ■~ -r ZJ CD GO - 1 - z 5= ° t 3 2 s o o CD C3 "^ CD 5 3 o x U 3 - 03 a o CO O h-5 to K ^"■3 be <-l - ,3 § o o two rt CVJ O J3 . 03 c3 CO j- a> O rt ^ ■Pa S o3 « 5 «3 en 1 Fi — X o o3^-i 175 .2 3 +J _03 be a: r5 53 CD K cs M gB F 03" / 7t 3 co en ~ •3^ o> i fa « £ 7^ cS *io o -J 03 X O 150 CALIFORNIA FISH AND GAME The situation on the McManus area was somewhat different. The greatest number on this area were local hunters and hunters from the San Francisco Bay area were second. Again, hunters from the other regions were few. Kill The kill of wild resident birds on the Sartain area in 1949 was 1,073. This is 347 less than were killed on the implanted McManus area. In 1948, there was a kill of 290 more wild birds on the Sartain ranch than on the McManus area. The higher kill on the McManus area in 1949 can be attributed partly to a hunting pressure estimated to be 45 percent greater than that on Sartain 's. Further, the immediate preseason and inseason 240 en UJ 12 o X 10 z => o 8 6 4 2 DAY OF SEASON Figure 76. Daily percentage of birds killed on the McManus area SEASONAL AVERAGES 1947 - 81 1948 - 65 1949- 8.0 153 50 40 30 20 10 1947 M948 1949 I 8 10 DAY OF SEASON Figure 77. Hunter success as measured by gun hours per bird on the Sartain Ranch 154 CALIFORNIA FISH AND GAME pressure on a smaller cock population resulted in a larger percentage of the total kill being made earty in the season. H tinting Success Hunting season success can be expressed as birds killed per hunter or gun hours per bird bagged. Birds per hunter are given in Table 4 for 1947, 1948, and 1949, and gun hours per bird are shown day by day for each year in Figures 77 and 78. Figures 84 and 85 show the relation of Q (T GO or W a. CO or O I 3 SEASONAL AVERAGES 1948 - 5.4 1949-11. 1 1949 1948 DAY OF SEASON Figure 78. Hunter success as measured by gun hours per bird on the McManus area pressure and cock population in the field to success each year. The high success ratio in 1949 on Sartain's as compared with McManus is un- doubtedly due to the heavy plant of game farm and wild birds before and during the season. If the kill of these is deducted from the total kill, the success per hunter drops from 0.60 to 0.38 birds per hunter, which is comparable to the McManus for 1949. In other years, success on the two areas was similar. Table 9 shows the birds per hunter for each day of the season for both areas during 1949. PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY 155 TABLE 9 Birds Per Hunter Day, 1949 Day of season Season's 1 2 3 4 5 6 7 8 9 10 average .96 .50 .32 .26 .36 .27 .49 .29 .98 .25 .63 .29 .38 .27 .36 .34 .27 .25 .84 .23 .60 McManus -- .34 Success is highest on the first day and decreases considerably on the second and third days. More hours are required per bird bagged on each successive day. After the third day, when heavy pressure drops off, success increases slightly as fewer and more persistent hunters are in the field. Success reaches a low point on the last two days although pressure increases. However, the heavy kill in the restricted zone on the Sartain ranch on the last day of the 1948 and 1949 seasons increased the hunter success over the entire area for the day. Of the 125 birds killed that day in 1949, 88 were taken in the restricted zone by 60 hunters. Higher success per hunter on the fifth and sixth days of the 1949 season on Sartain 's is due to the inseason release of 193 game farm cocks on the evening of the fourth day. Pressure, success, and total population are closely interrelated. Fig- ures 84 and 85 depict these factors graphically. The year of highest cock population on Sartain 's was 1948. It supported the greatest pressure (gun hours per 1,000 acres) and gave the highest success (the lowest gun hours per bird). Furthermore, a greater number of cocks was left after the season than in any other year. The pressure in 1949 on McManus was greater than in 1948 and the population was less. Poorer success resulted although the percentage of cocks taken was comparable. Less pressure would have resulted in approximately the same kill. It appears that there has been more pressure each year than was necessary for a satisfactory harvest. It seems evident that after the first three days of the season the cock population is so reduced that further kill will be slight regardless of addi- tional hunting pressure. A means of closely determining the point of diminishing returns is to compute the number of gun hours expended each year in bagging 80 percent of the kill. These figures are given in Table 10. TABLE 10 Point at Which 80 Percent of Kill Was Bagged Year Sartain McManus Gun hours/ 1,000 acres Day of season Gun hours/ 1,000 acres Day of season 1947 840 1,965 1,475 4 3 4 1948 1,384 1,526 4 1949 3 Figures 75 and 76 show that between 40 and 50 percent of the total kill occurs on the first clay and between 70 and 85 percent on the first three days. By comparison, 25-35 percent of the pressure comes on the 156 CALIFORNIA FISH AND GAME first day and 70-85 percent on the first three days (Figures 71 and 72). Comparatively few hunters are in the field after the first three days. The rate of decreasing success throughout the season indicates that a longer season would have little effect in increasing the total kill. Con- versely, a shorter season would still yield about the same bag. Kill of Stocked Birds vs. Resident Wild Birds The kill on Sartain 's was increased by planting game farm stock, and in 1949 by transplanted wild birds. Figure 79 gives the relative impor- tance in 1948 and 1949 of stocked and resident birds in the daily and sea- sonal kill. In 1947 the kill from 300 game farm birds made up 9.6 percent LlI o a: Ul 0_ 100 80 60 40 20 • GAME FARM BIROS, PRE- SEASON RELEASE ^\ S ^\ RESIDENT WILD BIROS \. \NN \ . X i > * X . \ \ Nv' 8 9 10 100 80 60 40 20 DAY OF SEASON 1948 UJ o s CALIFORNIA FISH AND GAME In 1948 the number of pheasants, especially cocks, in the Sacramento Val- ley was considerably greater than in either 1947 or 1949. Of the total seasonal kill in 1949, 45.9 percent of the wild residents, 75.0 percent of the preseason game farm release, and 59.5 percent of the transplanted wild birds were taken on the opening day (Figure 80). In contrast to this, 50.4 percent of the total kill of wild resident birds and 54.6 percent of the bag of game farm birds were taken on opening day in 1948. The higher take of game farm and transplanted wild birds on open- ing day in 1949 was due to the location where these birds were liberated. As stated previously, all releases of birds were made on a 1,680 acre tract under the pheasant planting policy. Hunting pressure on this and closely adjacent areas was considerably higher than on any other part of the ranch. This resulted in the take of these birds in a higher proportion to wild resident cocks than occurred in 1948, when the game farm cocks were more evenly distributed over the ranch and hunting pressure on the first day was not concentrated in the areas of release. Age Ratios The method employed in aging birds in 1947, 1948, and 1949 was by probing the bursa of Fabricus. The results obtained are considered to be accurate, if the validity of bursa measurements for age determination can TABLE 11 Age Groups of Kill Sartain McManus Year Adults Indeterminate t Young Adults Indeterminate Young No. % No. % No. % No. % No. % No. % 1947 12 11 46 11.7 4.1 17.5 2 3 8 1.9 1.1 3.0 89 252 209 86.4 94.7 79.5 36 41 54 15.9 13.4 23.5 7 9 12 3.1 2.9 5.2 183 257 164 81.0 1948 1949 83.7 71.3 be relied upon, as all probing was done by experienced personnel and a sample of each day's kill was taken. Table 11 shows the age groups of the kill from 1947 to 1949. The 1949 data indicate a decrease in percentage of juvenile birds in the populations on both areas from 1947 and 1948. The spring nesting and brood count studies indicated that there would be a decreased number of young birds in 1949. Figure 81 shows the frequency distribution of bursa depths of birds killed on the Sartain area. Comparable data for the McManus area are given in Figure 82. Each year these data have been distributed in the form of a bimodal curve with gaps at the 6-8 mm. class. This class has been considered to be birds of indeterminate ages rather than adult or juvenile. It is believed that these birds are either adults that have retained deep bursae or juveniles that have had a more rapid shortening of bursae than others. However, in 1949 there was an indication that bursa measure- ments for age determination are not as reliable as was once believed. PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY 159 It has been said that the kill of adult birds rises during the last part of the season and that a larger percentage of the immature birds are shot during the first days of the season. The percentage kill of young birds in each day's kill in 1949 is shown in Figure 83. The curve reflects a fairly equal kill of adults and young in each day's take. Although there are variations from day to day, there is no indication that young birds are taken in higher proportion in any particular part of the season. I 10 I 100 - 90 - 80 70 60 S 50 a: 40 30 20 10 1947 1948 1949 0-2 3-5 6-8 9-1 12-14 15-17 18-20 21-23 24"26 27" BURSA DEPTH IN MILLIMETERS Figure 81. Frequency distribution of bursa depths, Sartain area 160 CALIFORNIA FISH AND GAME 120 no . 100 90 80 4 1947 [ 1948 3-5 6-8 9-11 12-14 15-17 18-20 21-23 24-26 27- BURSA DEPTH IN MILLIMETERS Figure 82. Frequency distribution of bursa depths, McManus area PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY 161 100 iu 50 . o q: X 40 30 20 10 SEASONAL^ AVERAGE 74.1% 8 DAY OF SEASON Figure 83. Percentage of young birds in each day's kill of wild birds, Sartain and McManus areas combined, 1949 POPULATIONS Information on cock-hen ratios needed for satisfactory reproduction in the wild was obtained in the course of this study. Extremely high hunt- ing pressures each year reduced the cock population on the study areas to 15 or less cocks per 100 hens. The postseason sex ratios on the Sartain area were 3.4:100 in 1946 and 5.4:100 in 1947. Each year these ratios resulted in apparently normal reproduction. Low sex ratios on both areas were probably increased before the breeding season by an influx of cocks from surrounding areas in which the density of cocks was higher. A count on Sartain 's, early in the spring of 1947, showed that the sex ratio had increased to 22 :100. The density of the hen population was probably another factor con- tributing to high fertility that occurred with low sex ratios. From 1947 to 1949 the average acres per hen varied from 1.1 to 1.7 on the two areas, making it possible for a cock to collect a large harem from a small area. With habitat conditions that exist in the Sacramento Valley, it does not appear that hunting pressure can reduce the cock population to the point where fertility will be endangered. Stocking of cocks to provide apparently favorable sex ratios for breeding is, therefore, unnecesary. 162 CALIFORNIA FISH AND GAME Population Indices Differential Sex Ratio Method The approximate total populations of the two experimental areas can be computed by use of the Kelker Index, using preseason and postseason sex ratios and total kill in the following formulae : Preseason sex ratio times hen kill minus total cock kill Postseason hen Postseason sex ratio minus preseason sex ratio population Postseason hen population plus hen kill = Preseason hen population Preseason hen population times preseason sex ratio = Preseason cock population Preseason cock population minus total cock kill = Postseason cock population Crippling losses must be added to the checked cock kill to obtain total cock kill figures. In 1947 and 1948 the crippling loss was estimated at 30 per- cent of the number of cocks bagged, and illegal kill of hens was estimated at 5 percent of the cock bag. Crippling loss of cocks in 1949 was estimated at 20 percent of the bag, based upon hunter questionnaires. TABLE 12 Yearly Values Used in Calculating Total Populations by Use of the K elker Index Sartain McManus 1947 1948 1949 1947 1948 1949 Preseason sex ratio 1 .34 .05 1,023 307 51 .88 .15 3,150 945 158 .57 .15 1,481 296 74 .37 .10 958 287 48 .70 .10 2,656 797 133 .36 Postseason sex ratio 1 .10 Checked kill of cocks 1,420 Crippling loss of cocks 2 284 Hen kill 71 1 Males per female. 2 Considered to be 30 percent of cock bag in 1947 and 1948, and 20 percent in 1949. Table 12 gives the data that are needed to use the Kelker Index. Sex ratios are given as cocks per single hen, as used in the formula. Kill of the game farm birds released on Sartain 's after preseason sex ratios were taken are not included in the checked kill of cocks. Harvest of these releases of game farm birds was so complete that the survivors were considered to have little effect upon postseason sex ratios. The above sex ratio formula differs slightly from the one used in 1947 and 1948 hunting season reports. For comparison, populations for TABLE 13 Approximate Total Pheasant Populations and Percent of Cock Kill Preseason Postseason Percent Hens Cocks Total Hens Cocks Total cock kill Sartain 1947 4,600 5,600 4,200 4,600 5,700 6,500 1,550 4,900 2,400 1,700 4,000 2,300 6,150 10,500 6,600 6,300 9,700 8,800 4,500 5,400 4,100 4,500 5,600 6,400 230 810 620 450 560 620 4,730 6,210 4,720 4,950 6,160 7,020 85 1948, 83 1949 McManus 1947 74 74 1948 86 1949 73 PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY 163 all three years have been calculated using the same method. Table 13 gives rounded-off population figures and the percentage of the cock population killed each year. There is a direct proportion between the cock population before the season and the number of cocks left after the season. When the preseason population is high, the postseason is high, although the percentage re- maining is closely similar from year to year (Figures 84 and 85.) 1949 Figure 84. Pressure-success-population relationships on the Sartain Ranch. "* Total kill per 1,000 acres" includes crippling loss, but not the kill from game farm releases made after October. 164 3pOO 2,800 2,000 2,400 2,000 2,000 1,800 1,600 1,400 1,200 1,000 CALIFORNIA FISH AND GAME XX^ GUN HOURS PER BIRD BAGGED X///\ TOTAL KILL PER 1000 ACRES PRE-SEASON COCK POPULATION PER 1000 ACRES GUN HOURS PER 1000 ACRES 1947 1948 1949 Figure 85. Pressure-success-population relationships on the McManus area Lincoln Index This method involves a simple proportion : Cocks present before season Total number banded birds Total cocks killed Number banded birds killed In computing the pheasant population in 1949 on the Sartain area, returns from wild transplanted birds were used. A total of 98 bands was returned from 150 adult and juvenile wild cocks released on Sar- tain 's during September and October. The total checked kill on the area, PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY 165 subtracting the kill of game farm birds released after October, was 1,481. The above data substituted in the Lincoln Index give : X 150 — and 1,481 98 X = 2,267 cocks before the season. Rounding this figure off in the same manner used with Kelker Index figures gives a preseason cock population of 2,300. This compares very closely with the figure of 2,400 obtained by use of the Kelker Index. There was no basis for using the Lincoln Index to cheek on popu- lation figures of the McManus area because no birds were banded. Effect of Game Farm Hens on Total Population Calculated total population figures show that the over-all effect of heavy stocking of game farm birds as a means of increasing the total population by breeding was at best slight and possibly of no significance. Reproduction by 500 hens released in 1947 and by 560 hens released in 1948 on Sartain's would have affected the 1948 and 1949 population figures if the effect were of measurable extent. The 650 hens released in 1949, of course, could not yet have affected the population by breeding. However, as shown in Table 14, the population per unit area was greater on Sartain's in 1947, increased over the McManus area somewhat in 1948, but was less in 1949. TABLE 14 Approximate Pheasant Populations Per 1,000 Acres Before the Hunting Season 1947 1948 1949 Sartain McManus. _ 890 805 1,520 1,245 955 1,130 It should be borne in mind that population figures on Sartain's include survivors of game farm releases made before November of each year. These include 220 birds in 1946, 800 in 1947, 1,259 in 1948, and 1,399 in 1949 — a total of 3,658 game farm birds. Yet, even with these game farm birds, the population on Sartain's, which was 22 percent greater than that on the McManus area in 1948, was 15 percent less in 1949. The question arises as to what happened to the game farm hens released on the Sartain area, if their release made no noticeable effect on the pheasant population. Follow-up searches made soon after libera- tions, near release sites, showed that mortality of game farm birds of both sexes was often great. All birds were released in good condition before the heat of the day, with time spent in crates less than four hours and hauling distances not more than 35 miles. During live trapping operations using spotlights at night in the summer of 1949, 277 adult hens were caught on Sartain's. These included only four game farm hens from 1948 releases, while there were none from 1947 releases. Thus game farm hens, making up approximately 6 to 166 CALIFORNIA FISH AND GAME 10 percent of the hen population when released, made up only 1.5 per- cent of a sample of the same population one year later, and had disap- peared entirely two years later. SURVIVAL AND RETURN OF GAME FARM BIRDS Banded game farm birds were released on the Sartain study area from 1946 to 1949. Birds from 6 to 12 weeks of age were stocked to determine the best age to plant for survival from summer releases. All age classes in a release were liberated at the same site. Older age groups were stocked to measure return in relation to length of time in the field before the hunting season. In 1949, the various age classes were released on dates corresponding as closely as possible to the 1948 release dates. A summary of 1948 and 1949 plants with hunting season returns is pre- sented in Table 15. TABLE 15 Return of Game Farm Birds From Sartain Releases by Age Classes and Days in the Field, 1948 and 1949 Age released Number released Date of release Days in field (before season) Percent return (weeks) 1948 1949 6 8 50 50 50 50 50 June 11 11 24-25 24-25 25 159-161 161 146-147 146-147 147 8 10 4 22 50 10 6 8 4 16 10 6 8 50 50 50 July 15 15 15 125 125 125 - 2 22 9 36 6 50 50 50 100* August 5-18 5-18 5-18 12-18 93-106 93-106 93-106 93-99 14 28 35 8 22 10 12 12 24 11 14 inn 100 September 14 13 66 65 43 46 14 16 100 100 October 1 4 18 34 32 55 56 16 18 99 99 November 17 16 2 2 81 84 Sub-totals 1948 1949 799 848 35 32 20 193 November 21 In season -- 69 Grand totals 1948. 799 1041 35 39 1949. * 99 birds in 1949. Mortality Soon After Release Following liberation of 1,399 birds of both sexes in 1949, 109 dead birds (7.8 percent) were found. In 1948, 20 dead birds (1.7 percent) were found from a total of 1,160 liberated. More thorough follow-up searches were made in 1949 which accounted for the greater number of dead birds found. Numerous additional remains were found in the vicin- ity of release, but were not counted in the total as bands could not be located. Actual losses were greater as only small areas about release sites were searched. Consequently, birds moving away before dying were not found. Figure 86 shows immediate mortality of game farm birds released PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY 167 15 < bJ Q O z O t- z ai o or UJ a. 1949 1948 JUNE JULY AUG SEPT. ' OCT. BY DATE OF RELEASE NOV. 15 < UJ Q O UJ o 8, 10 & 12 45 199 Aug. 11-28 Aug. 16 90 93 44.4 20.6 Wild.. 10-14 12 59 100 Sept. 7-8 Sept. 13 72... __ 65 44.1 Game farm 45.0 Wild. 12 II, 14 49 100 Sept. 22- Oct. 11 Oct. 14 48 57.1 Game farm 34 56.0 Wild 6-16 6-14 All juvenilt July 15- ( 263 599 s released Dctober 14 45.6 Game farm 28.9 A comparison of the returns of game farm stock and wild trans- planted stock, of comparable age classes and days in the field before the hunting season, is shown in Table 19. The return from 6- to 10-week-okl birds released in July is almost three times as great for transplanted wild stock as for game farm birds. Wild birds transplanted in August yielded a return more than twice that of comparable game farm birds. Returns from liberations made in September and October were similar for game farm birds and wild transplanted stock. This indicates that survival of juvenile wild birds was considerably greater than game farm birds of similar age released before mid-August, but almost equal for September and October releases. Daily percentages of the total seasonal kill of transplanted wild birds were in general comparable to those of resident wild birds (Figure 80 ) . The somewhat greater percentage of kill occurring on the first day among transplanted birds was caused by greater hunting pressure being exerted on these birds which were released in the pheasant planting policy area. Wild banded birds showed little tendency to move any appreciable distance. Of a total of 344 band returns from wild birds, 96.1 percent was from the Sartain study area or along its borders. None of the adults were taken off the area ; all outside returns were from juvenile cocks. A resident juvenile cock banded 3i months before the season was taken 15 miles away ; all other returns were from six miles or less. Transplanted juvenile cocks evidently did not move as much as resident juvenile males, PHEASANT POPULATIONS IN THE SACKAMENTO VALLEY 173 and adult cocks, both resident and transplanted, did not move off the area after liberation. MISCELLANEOUS DATA Aging Methods Used — 1946-1949 Birds were aged by three methods during the four-year check. In 1946 and 1947 aging was accomplished by examination of spur lengths and by testing the hardness of the lower mandible. In 1947 the bursa of Fabricius was also used. The first methods were found to be inaccurate and in 1948 and 1949. probing the bursa of Fabricius was employed to determine old-young ratios. A discrepancy was found in bursa measurements of adult wild birds in 1949. The bursa depths of 35 wild adult birds trapped and banded in the summer of 194!), and killed during the 1949 season, had a variance from to 19 millimeters. The bursa measurements of the 35 adults varied as follows: ten from 10 to 19 mm.; six from 6 to 10 mm.; six between 2 and (i mm. ; and thirteen with no bursa. Juvenile wild cocks, which were banded in the summer of 1949, were all found to possess a bursa depth of greater than 10 mm. when taken during the hunting season. Further work on banded wild birds will test the validity of measuring the bursa of Fabricius for age determination of wild birds. As stated previously, all measurements were taken by experienced personnel. Weights Samples of the birds killed during the 1946-1949 hunting seasons on both the Sartain and McManus areas were weighed in grams on triple beam balances. The weights of wild birds converted to pounds and ounces are given in Table 20. TABLE 20 Weights of Wild Cock Pheasants From Sartain and McManus Areas, 1946-1949 Number of birds Average Maximum Minimum 1946 1947 37 197 938 461 1,633 2 lbs. 1 1 oz. 2 lbs. 11 oz. 2 lbs. 1 1 oz. 2 lbs. 10 oz. 2 lbs. 1 1 oz. 3 lbs. 3 oz. 3 lbs. 9 oz. 3 lbs. 6 oz. 3 lbs. 9 oz. 3 lbs. 9 oz. 2 lbs. 2 oz. 2 lbs. 1 oz. 1948 1 lb. 13 oz. 1949 1 lb. 14 oz. Over-all 1 lb. 13 oz. The average weight of wild birds was 2 lb. 11 oz. in the first three years and 2 lb. 10 oz. in 1949. In 1949, 44 game farm birds killed had an average weight of 2 lb. 8 oz. which was the same as in 1947 and 1948. The reason for the lower average weight of uame farm birds was that the main kill consisted of late-hatched birds released shortly before the season. CONCLUSIONS Heavy hunting pressure and game farm stocking have had little effect on pheasant breeding populations in the Sacramento Valley. Under present habitat conditions, regulation of hunting pressures or numbers of hunters per unit of area to preserve male breeders is not necessary. However, controlled hunting reduces the possibility of damage to prop- erty and accidents to hunters. The study areas had extreme hunting pres- sures, probably not exceeded anywhere in the State during the four year 3—39247 174 I AUKOKXIA FISH AXD GAME check, yet reproduction by wild stock was satisfactory for maintaining a sustained yield of cocks. Little is gained by planting game farm birds year after year in high quality pheasant habitat supporting optimum pheasant populations. Very small percentages of game farm cocks and hens live until spring and thus do not measurably increase the breeding population. The seasonal kill lias not been greatly increased by the kill of game farm birds except when they have been released against the gun, which is expensive shooting. Small benefit can be realized from further plant- ings of game farm pheasants in the Sacramento Valley. However, game farm production has been increased each year in California. The best utilization that can be made of these birds is to plant them for the gun immediately prior to or during the hunting season. Under the present system of obtaining maximum production from game farms, the pens are filled twice during each hatching season. The early-hatched birds must be liberated during the summer to provide space for the late- hatched ones. If no system can be provided to hold them until fall, these birds can best be utilized by releasing them at the age of 10 to 12 weeks in -July. At best the returns are low. Most of these birds contribute noth- ing to increasing either hunting success or breeding stock and, therefore, are considered to be a total loss. , Limited stocking may be desirable where pheasant habitat has been developed through changes in land use, or on areas of decimated popula- tions. Birds for these plants can probably be obtained more economically and efficiently by removing wild stock from inviolate refuges. Opening areas to hunting that have heretofore been closed will make more birds available to the hunter than any other single management method. Recent management efforts have been directed toward this end. Attempts to increase pheasant production are impractical in the Sacra- mento Valley, where the present production remains largely unavailable to the hunter. The 1947 and 1948 hunting seasons on the Sartain ranch were con- ducted and regulated through the cooperation of landowner, sportsmen, and the California Division of Fish and Game. The success of controlled hunting on this area led to the adoption of the cooperative hunting area plan, and in 1949 six areas were established on which the Division regu- lated the hunting. These were deemed a success by both landowners and sportsmen, and plans were made to expand the number of these areas in succeeding years. SUMMARY A four-year pheasant hunting study was n ade on two comparable areas in the rice belt of the Sacramento Valley from 1946 to 1949. One area, the Sartain, received plants of pheasants, while the other, the McManus, was not planted. Hunter checks were made at stations on roads leading off the areas each year except 1946. Additional data were obtained from airplane counts of pheasant hunter's cars in a 269 square mile portion of the Sacramento Valley, which included the study areas, from 1947 to 1949. A 10-day season with a limit of two cocks per day and 10 per season was in force during the four-year study. PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY 175 Local hunters were more in evidence on the McManus area than on Sartain 's. San Francisco Bay region hunters constituted the largest single group on Sartain 's. Fewer hunters were in the field in 1949 than in 1948. Hunting pres- sure in 1949 on the Sartain area was almost half that of 1948 and was comparable to 1947. However, the McManus area had only a slight reduction in numbers of hunters in 1949. Both areas had a decided increase in hunters in 1948 over 1947. On the first three days of the season, 70 to 85 percent of the seasonal hunting pressure is exerted and approximately 70 percent of the total kill is taken. Hunting success is highest on the first day, decreases by about one-half on the second day, and remains at a generally low level for the remainder of the season . Before heavy game farm planting began on Sartain 's in 1947, the total population per unit area was greater than on the McManus area, and the kill of wild birds was correspondingly greater. Although there was a heavy planting of hens on the Sartain area in 1947, the increase of both total population and kill in 1948 was only slightly greater than on the McManus area. Continued heavy planting of hens on Sartain 's in li)48 failed to result in further increases in 1949. Instead, both total population and kill per unit area decreased to less than that of the McManus area. It is evident that the planting of game farm hens has no measurable lasting or cumulative effect in increasing pheasant production where optimum pheasant populations already exist. The greatest benefit to be derived from game farm pheasants is to plant cocks shortly before or during the season in areas where hunting pressure is high. This planting method has resulted in the greatest bag of birds released and in years of low wild populations has considerably increased the total kill. Returns from game farm birds released before the season in 1949 averaged 32 percent. This is remarkably comparable to the 1948 return which was 35 percent. The greatest returns, 81 to 84 percent, were realized from liberations of mature birds made two days before the season. Older birds gave higher returns than younger birds released on the same dates three months or more before the season. August proved to be the most unfavorable summer month for liberations. Returns from transplanted wild birds were considerably greater than from game farm birds when both were liberated at comparable ages three months or more before the season. Losses of both leg and wing bands were negligible. Bursa measurements made on wild pheasants in 1949 indicate that this age determination criterion may not be as reliable as once thought. A high percentage of the wild adult cocks banded in the previous summer had bursas measuring from (j to 19 millimeters in depth when taken dur- ing the hunting season. Heavy hunting pressures have resulted in low cock populations after the season each year. However, the normal reproduction that has resulted each year has shown that the numbers of wild cocks have been ample for breeding purposes without supplementary stocking of males. 17(i CALIFORNIA FISH AND GAME ( Opening areas closed to pheasant hunters lias been the most pressing' management problem in increasing the. kill of pheasants. The success of hunting controlled by the Division of Fish and Game on the Sartain ranch led to the adoption of the cooperative hunting area plan in California in 1949. Six areas were operated under this plan in 1949. The favorable reception of these by landowners and sportsmen, has led to plans for increasing the program in future years. REFERENCE Harper, Harold T., George .Metcalfe, and John F. Davis lU."iO. T'pland same cooperative hunting areas. California Fish and Game, vol. 36, no. 4. ] i. 404-432. FOOD HABITS OF FERAL HOUSE CATS IN THE SACRAMENTO VALLEY 1 By Eari. L. Hubbs Museum of Vertebrate Zoology, University of California, Berkeley INTRODUCTION The house cat, Felis (io)iicsticns, is widely recognized as a predator of various farm game species and song birds, while at the same time it is known to take many rodent pests. The economic status of the free-hunting cat is a moot question that must be solved for each area by local food habits .studies. Such a study is here presented. The area under consideration is the rich, agricultural valley of the Sacramento River, 150 miles long and 50 to 60 miles wide, lying between the north coast ranges and the northern Sierra Nevada of California. The land is relatively flat — most of it less than 100 feet above sea level and much of it under irrigation. Rice, other cereal grains, various fruits, and livestock are the main crops. The pheasant is the only upland game bird present in abundance, but myriads of waterfowl and shore birds winter in the valley. A sparse population of ducks stays to breed on the irrigation ditches, flooded rice fields and few permanent sloughs. Song birds, small rodents, cottontails and black-tailed jack rabbits are numerous. Under these conditions feral house cats have an abundant, year-long selection of prey species, and the purpose of this study has been to ascertain the sea- sonal food habits of cats with special emphasis on their relations to game species. Acknowledgments are due Dr. A. Starker Leopold of the University of California under whose guidance the study was conducted. I am like- wise indebted to Daniel Tillotson, John Chattiii, Carol Ferrel and Howard Leach of the California Division of Fish and Game for gener- ously making available materials and equipment of the Food Habits Laboratory in Berkeley, and for personal aid in pursuing the study ; to held personnel of the Division and others for assistance in the collection of stomachs; and to personnel of the Division of Entomology and the Museum of Vertebrate Zoology, University of California, for aid in identifying materials. FERAL CAT POPULATIONS Li this report the terms ' ' feral ' ' and ' ' vagrant ' ' shall refer to all the cats examined in the study. Though all were taken in the field at consid- erable distances from human habitation, it is acknowledged that many doubtless were wanderers from farm buildings and were not permanently resident in the wild. However, some cats in the Sacramento Valley are known to breed in the field and to be truly feral. On February 22, 1948, A. S. Leopold and Ward Russell killed a pregnant female in the mouth of her den on the Conaway Ranch, Yolo County. She contained six em- bryos almost ready for birth. Presumably they would have been deposited 1 Submitted for publication October, 1950. I 177 ) 178 CALIFORNIA FISH AND GAME in the ditch-bank den which was nearly two miles from the nearest farm building. A week previously an employee of the Conaway Ranch had killed a female with eight young kittens in a similar den nearby. A lac- tating female was taken November 24. l!)4f), in the same general area. Such records of house cats breeding in tbe field are quite numerous in the valley. The percentage of cats examined in this study which were actually wild bred is unknown, but such differentiation is somewhat academic since vagrant cats probably are similar in feeding habits, whether they were born in a barn or under a ditch bank. In the North Central States, Leopold (1931) found little evidence of house cats breeding in the wild, and he states that field populations must be regularly replenished by "drift" from places of human habita- tion. Nilsson (1940), in his study of house cats in the Willamette Valley of Oregon, found no indications of kittens being produced in the wild and he agrees with Leopold's conclusion. It is probable likewise that most of the animals taken in the Sacramento Valley were barnyard strays, but in this mild climate there seems to be more tendency toward wild breeding than in areas of higher latitude. Leopold states further that there is a general scarcity of wild females, a fact which would preclude much breeding in the wild. Nilsson found that 77.5 percent of 147 house cats taken in his study were males and considers this an indication that wild females are scarce, or that farm females do not wander as much as the males. The sex ratio of the cats taken in the Sacramento Valley does not support this conclusion. Of 219 animals examined, 104 were males, 95 females, 17 immatures and three were unclassified. In this area the sex ratio seems to be very nearly balanced. Only scattered figures are available which indicate actual densities of vagrant cat populations in the valley. On the Gray Lodge State Waterfowl Refuge near Gridley, Butte County, 82 eats were taken in 1949 on 2,600 acres, which gives a minimum population of a cat per 32 acres. This take was accomplished in 34 days of trapping and doubtless did not result in complete elimination of the population. A rancher near Colusa killed 650 cats on his 14,000 acre rice ranch between January. 1949, and January, 1950 — a removal of one cat per 21 acres through a calendar year. This operation, which was conducted with dogs and guns, was more intensive than the trapping on Gray Lodge Refuge. It is prob- able that in many parts of the valley, where ground cover is dense, popu- lations of a cat per 20 acres are not unusual. Doubtless lesser densities exist on the more open lands. House cats in the Sacramento Valley have few natural enemies except men and dogs. Coyotes, once common in the area, are known to kill cats (Bond, 1939; Sumner, 1933), and so also do bobcats (Grinnell et al., 1937). However, both of these wild predators are now scarce due to intensive agricultural development. Internal parasites found in the stomachs did not suggest that parasitism is an important controlling factor on populations. In the 219 stomachs examined, I found tapeworms in six and nematodes in 43, which probably is no higher a rate of infection than would be found in an equal sample of well-kept tabbies. In summary, the vagrant cat population existing in the Sacramento Valley consists of some animals raised in the wild and doubtless many strays from farms. Densities up to 32 animals per square mile (one per FOOD HABITS OF FERAL HOUSE CATS 179 20 acres) are known, but over most of the valley actual densities prob- ably average much lower. Populations presumably are controlled by man and dogs directly and are limited indirectly by the available food supply, since natural predators of house cats are scarce and parasitism seems to be light. FOOD HABITS MATERIALS In all, 219 cat stomachs were examined in the study. Thirty-five were empty or contained only debris so were not used. The stomachs, which were collected from 1940 to -January, 1950, were sorted by months with no regard to the year taken. The heaviest take was in the spring months of March. April and May when 119 animals were collected; 38 were taken in the summer months — June, July and August; 17 in the fall — September, October and November ; and 45 in the winter — Decem- ber through February. Table 1 gives the number of stomachs examined from each month. TABLE 1 Distribution of Sample of Cat Stomachs, by Months January February March, _ _._ April . 11 29 56 45 Mav June Julv-_ August 18 5 2D 13 September... October. . November December Total 10 3 4 5 219 One hundred and sixty-nine of the cats were captured in Butte County (71 of these on Gray Lodge Refuge), 15 in Colusa County, 29 in Glenn County and six in Yolo County (Figure 88). Collections were made by three methods: shooting (133), trapping (66) and dogs (18). Two additional road-killed cats were recovered. Shooting or capture by dogs seems to be a better method than trapping for obtaining animals for use in food studies, because the stomachs of nearly one-half of the trapped animals contained nothing or so little that they could not be used. It appears that after about 12 hours most of the contents of a cat's stomach have been passed. The data presented in this report were compiled from stomach analysis findings only. The methods of analysis and compilation here followed are those in use by the California Division of Fish and Game Food Habits Laboratory. After the animal is killed in the field the stomach is preserved in 10 percent formalin and shipped to the laboratory where the contents are measured volumetrically by water displacement. The material is then oven-dried and the contents identified, an approxi- mate percentage of the total content being recorded for each food item found in the stomach. The number of individuals of a given prey is also determined when possible. Mammal and bird remains are usually identi- fied by bones or by general appearance of fur or plumage. When this proves impossible one must resort to microscopic hair and feather analysis. Species identification was checked by consulting geographic ranges in Grinned and Miller (1944) for birds and Grinned (1933) for mam- Of the 219 stomachs here considered, 153 were analyzed by the author during the study, 66 having been analyzed by Fish and Game personnel prior to the commencement of my work. 180 CALIFORNIA FISH AND GAME OLENN CO CENTRAL PART OF THC SACRAMENTO VALLEY CAT LOCALITIES a NUMBERS Figure 88. The central part of the Sacramento Valley, showing localities of house cat captures The results are summarized by the aggregate percentage method as described by Martin et al. (1946). This method, in general use in the California Food Habits Laboratory, is preferred since it tends to reduce distortion caused by a few overstuffed stomachs and gives a better indi- cation of the number of meals of the different food items than do aggre- gate gross volume or frequency of occurrence. Table 2 gives the percentages of each food item by month, yearly total, frequency of occurrence in the total sample, and the minimum aggregate of prey numbers. Figure 89 presents in graphic form the percentages of the main types of food occurring in the whole sample. Figure 90 pictures the shifting seasonal food pattern of the house cats. FOOD HABITS OF FERAL HOUSE CATS 181 26- 24-- 22" 20- 18- 16— 14- 12- 10— 8— 6— 4- 2-f" ??■? 238 13 3 VOLUME PERCENT of FOOD ITEMS FOUND in 184 HOUSE CAT STOMACHS I X Ui c5 at 31- 28 — Wl JQ Q T i Q :y in z Figure S9. Relative amounts of various classes of food consumed throughout the year by Sacramento Valley house cats JAN FEB MAR APR MAY JUN JUL AUG SEP OCT N0V„„Df9, ioor BIRDS REPTILES FISHES INSECTS MAMMALS Figure 90. 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' i i i « i i r 11^* w ii_ ; i ; :^^ : ; ; j"-s \ s ; i : : i : : : :-§.§ :::&'§ a :.s ; : : : : : : :Sl^ : :|1;t ',$•{ : : : : : -3 : ig-s.1^ :|8-g :£«;::; g i i-S c Sts u s| !§» . • . . 8 ISSfe »£■**" ^ ft "H « - 1 - s a .jt» * : o-s i-° i : » «, 2^&s^^ o <•> ;^,*s S3 »^ a 'O-osp-iit'SaCiJ^'o-oi] ; H a S-3 i o-c-a > Jc«8E"ii«i m-S o bC- SS-A**-^?^ M-OT3T3 — n c3 ■+a O H FOOD HABITS OF FERAL HOUSE CATS 183 -HO O 00 >- cc o^o OOfON o t^ CO too CO O -— i . i— i CO i CO |o — <«J« -*f Oi OJ „fc- TJH I l r «- 12 s'g.s -s « o i g- 1. e > © ^ p- I 3* g i »gg| S o i) a a ,t-H ,H 2 — 1 o do CD „ Q-T3 Q, jsrsg •Soph _a S £ S > 4) O ft-^ ^cZ a> a> £ g^fcSgSa&^S 1-3 o , (- © & o d 43 o 184 CALIFORNIA FISH AND GAME FINDINGS The food preferences of house cats in the Sacramento Valley were found to shift seasonally, mammals being most numerous in the fall and winter samples while birds were more frequently taken in the late spring and summer. Insects, reptiles and fish were all more common in stomachs taken during warmer seasons. This seasonal variability of the cat's diet suggests a constant adjustment to availability of various types of prey and is not necessarily a direct reflection of preference. Considering the yearly diet as a whole, mammals, particularly small rodents, make up the majority of both individuals and bulk taken. It is often stated that birds constitute the heaviest part of the house cat 's diet. This contention, usually based on casual observation, is not borne out by my findings nor by those of other investigators who have actually analyzed stomach contents. Nilsson found that 86 cats taken in the Willamette Valley contained 61.8 percent mammals and only IS.!) per- cent birds by volume. Errington (1936), in Ids study of the food habits of Wisconsin house cats found 57 mammals and only nine birds in 50 stomachs. McMurry and Sperry (1941) studied 84 cat stomachs from several areas in Oklahoma. Mammals made up 55 percent of the bulk and birds only 4 percent. Bradt (1949) records the prey brought in by one tame kitten in Michigan. In a period of IS months it caught 1,623 small mammals. 1600 of them being mice, and only 62 small birds. Results from the study of Sacramento Valley cats showed that mammals constituted 64 percent of the total food and birds 25 percent. Mammals Three hundred eighty-one individual mammals appeared in 152 of the 184 stomachs and accounted for 64.1 percent of the total bulk as shown earlier. Twelve species, representing three orders — Roclentia, Lagomorpha and Carnivora — were identified. The rodents were subdivided into Old World and native forms as the two groups played separate roles in the cat's diet. The Old World rodents (domestic rats. Rutins norvegicus and B. rattus, and house mouse, Mus musculus) were found almost exclusively in the fall and winter and the native forms Largely in the warmer periods. This is as would be expected, for most of the native forms are at a low ebb in the winter months whereas the "overflow" of domestic rats and mice from farm- steads usually reaches a peak in late fall. Domestic rats are fairly numerous in the valley, around buildings and to some extent in the fields. But they do not contribute importantly to the diet of cats. There is a widespread belief that not many house cats kill and eat rats. The study bears this out as only eight individuals were taken. Errington 's study in Wisconsin revealed seven rats in 57 mammals. Kuo (1930) has shown experimentally that cats must be taught to kill rats, and that not all cats learn naturally. ( hi the other hand, 216 house mice were found in 86 stomachs. The house mouse w T as the most numerous single prey species and constituted 24.1 percent of the total yearly food. Many of them had no marks on their bodies, apparently being swallowed whole. In the Sacramento Valley these imported pests are found abundantly in granaries and grain fields. FOOD HABITS OP FERAL HOUSE CATS 185 The cats undoubtedly hunt them intensively as shown by the high fre- quency of occurrence and the large numbers of mice found in many individual stomachs. Native rodents appeared 92 times and had a combined total of 23.8 percent. Eighty-nine field voles (Microtus calif orniciis) were taken, mainly in the spring. They made up nearly two-thirds of the native rodent bulk and four-fifths of the total number. The pocket gopher (Thomomys boffin) was the only other native rodent taken in any quan- tity. Sixteen were found in 11 stomachs. Along with the voles they were the only American rodents caught in the winter months. Five white-footed mice (Peromyscus maniculatus) , three hat-vest mice (Reithrodontomys megalotis), one Beechey ground squirrel (Citcllus beecheyi), one wood rat (Neotoma fuscipes), and one pocket mouse (Perognathus sp.) were found and totaled 2.9 percent of the material. Rabbits and hares were found in 37 -stomachs, never more than one per cat. Twenty-seven were Sylvilagus sp. — probably mostly cottontails (8. audubonii), although a few may have been brush rabbits (8. bach- mani). The remainder consisted of six black-tailed jack rabbits (Lepus californicus) and four unclassified individuals. Probably most of the jack rabbits were eaten as carrion on the roads, though some may have been captured. Lagomorphs totaled 13.3 percent of the volume and were taken most frequently in the spring months. Remains of house eats appeared in three stomachs. One trapped animal contained part of a foot, perhaps its own. An adult female con- tained the remains of a nestling kitten, probably representing a case of maternal cannibalism. The third sample seemed to be carrion. The total absence of insectivores supports the belief that they are distasteful to carnivores. McMurry (1945) found three shrews (Cryp- iotis parva ) in one of 223 stomachs from Oklahoma. Bradt, in his account of the Michigan kitten, reports that 15 shrews were brought in but were not eaten. Errington reports only one shrew (Blarina sp.) from the 50 Wisconsin stomachs. On the other hand, Nilsson found six shrews (Sorex vagrans) and two moles (8capanus sp.) in 86 Oregon stomachs. Birds Birds were found in 74 stomachs, totaling 25.2 percent of the total bulk. Fifty-two of the 97 individuals were of game species. These results differ considerably from those of Nilsson in Oregon. In 86 house cat stomachs he found 26 birds, only three of them being of game species. For 63 cat samples he gives a figure of 22.2 percent for nongame birds and only 6.3 percent for game birds. Ten adult ducks were found in the spring samples. This relatively heavy take of ducks, making up 3.2 percent of the total hulk, was some- what surprising for there is little reference in the literature to cat preda- tion on adult ducks. Eight of the birds were hens. Many or all of them may have been mallards {Anas platyrhynchos) which breed in the valley in fair numbers. However, many closely related female ducks are so similar that no positive identification of the plumage fragments could be made. It is unlikely that these hens were cripples, for the dates when they were eaten were long after the California waterfowl season. It seems more probable that fliey were killed on their nests. Earl (1950), working on mallard production in the Sacramento Valley, lists the domestic cat as 186 CALIFORNIA FISH AXD GAME a major predator on mallard nests but makes no direct reference to attacks on the hens. The two remaining ducks were botli male pintails (Anas acuta). Thirty-three ring-necked pheasants (Phasianus colchicus) were found in 31 stomachs, accounting for 10.8 percent of the total sam- ple. The ages represented were not quite as expected. It is generally thought that the heaviest drain is on the chicks, but only four birds were identified as immature, two of them being found in the same stomach with remains of an adult hen. The majority of the pheasants were identi- fied as adult hens. Binarsen's (1942) work in Washington bears out these findings. He found that of 21 pheasants killed by cats, three were cocks, seven hens, one young and 10 were "unclassified." Undoubtedly some of the pheasants had been dead some time when eaten. Two were accompanied by carrion insects. However, there seem to have been few cripple losses represented in my sample, for most of the pheasants appeared several months after the hunting season. In fact, there was no increase in pheasant remains during the fall hunting season. All but five of the pheasants were taken between April and Septem- ber, the period covering nesting and brood development. They were most numerous in late spring and early summer which represents the peak of nesting. It is probable that cats impose quite a heavy pressure on the nest- ing hens in some areas. Such predation would be a more serious drain on the population than a heavier take of chicks alone. McAfee (1945) agrees that nesting hens are especially vulnerable to house cats. In addition cats may destroy pheasant nests without killing the hens. Current pheasant studies in the Sacramento Valley, being conducted by the California Division of Fish and Game, indicate that cats are one of the predators frequently causing nest destruction, although they are of less importance than raccoons or skunks. It is quite obvious that cats do not restrict their hunting to hens, chicks and nests, for several observations have been made of cats catching cock birds. Nilsson tells of a cat stalking a flock of pheasants and pounc- ing on a full grown cock and killing it. On the Conaway Ranch a cat was seen to flush a cock from the tide margin of an irrigation ditch and pull it down from the air. Other gallinaceous birds were scarce in the sample. There was one occurrence each of the California quail (Lophortyx califomica) and the domestic chicken (Gallus g alius). Eight stomachs contained remains of the American coot (Fulica americana) . This game bird would be easy prey for a vagrant cat as it does much wandering about on land. It is not known whether, the coots were captured or were eaten as road kills, for many are found dead on the roads in the valley. House cats have a particularly unsavory reputation as killers of song birds. McKenny (1939) sets the annual kill of small birds in Pennsyl- vania at 50,000,000 with the house cat as the major cause, and Forbush (1916) states that rural eats killed 7,000,000 birds in Massachusetts in 1913. Reed (1906) claims that a horde of cats were eating three-fourths of the song birds hatched. Undoubtedly house cats kill many song birds, but the findings of this study tend to discount these extravagant claims as do most other detailed food habits studies. Only 29 passerine birds were FOOD HABITS OF FERAL HOUSE CATS 187 found, accounting for 6.6 percent of the material. Fourteen undeter- mined song birds, two meadow-larks {Sturnella neglecta), three red-wings (Agelaius phoeniceus) , two Brewer blackbirds (Euphagus cyanocepha- lus), and eight sparrows were found. The take of passerine birds was gen- erally scattered throughout the year. One green heron {Butorides viresci ns I was eaten. This species is one of several herons found fairly commonly in the study area. Remains of bird eggs were found in only two stomachs — a small sample in the Light of all the nest destruction attributed to cats. How r ever, when a cat raids a nest it usually eats the contents of the eggs and does not ingest much shell which is the only traceable part to be found later in stomach analysis. Nilsson found no sign of eggs in the 86 Oregon house cat stomachs he examined. Stomach analyses probably do not accurately reflect the consumption of eggs by cats. Reptiles The remains of 13 snakes were found in the spring and summer material. Seven Pacific gopher snakes {Pituophis catenifer) , three yellow racers {Coluber constrictor) and one garter snake (Thamnopkis ordi- noides) were identified. The remaining two were of undetermined species. At least one of the snakes was probably carrion, as dirt w T as found pressed into the scales and meat. Fishes There was a general scarcity of fish remains. Teale (1948) cites many instances of cats fishing in ponds, but states that most cats, despite their love for fish, do not like to get wet. The cat's dislike for water can not explain the lack of fish in my sample, for many fish are stranded when the flooded rice fields dry in the summer. Fish were found in only seven stomachs, four times as trap bait. The common carp {Cyprinus carpio) was the only species identified. I nsects Insects appear to be an important item in the summer diet. Field crickets (Oryllus assimilis) and Jerusalem crickets {Stenopelmatus sp.) accounted for nearly 100 percent of the insect bulk. These insects are com- mon during the summer and could easily be caught by a prowling house cat. One stomach contained 80 cc. (almost \ cupful) of field crickets and nothing else. Carrion insects (several types of flies and beetles) were taken 12 times, probably indirectly with carrion. Other invertebrates included: Grasshoppers, one locust (T rimer otropis sp.), dragonflies, water beetles (family Ilydrophilidae), ants {Formica sp.), lepidopteran larvae, spiders and centipedes. McMurry and Sperry give a figure of 12.5 percent for insects, mainly grasshoppers and crickets, in their studies of cat food habits in Oklahoma. Errington reports that five of the 50 Wisconsin house cats were high in grasshoppers, crickets, and June beetles. In my sample, insects consti- tuted 7.4 percent of the total food. Debris In addition to the food itemized, debris was found in 77 of the stomachs. Included in this category were : Grass, sticks, dirt and cat hair. Approximately one-third of the stomachs contained small quantities of green grass. The loose cat hair w 7 as undoubtedly ingested as a result of L88 CALIFORNIA FISH AND GAME licking the fur. The sticks and dirt were found mostly in the stomachs of trapped animals. DISCUSSION The results of this study indicate that feral house cats in the Sacra- mento Valley have a shifting seasonal diet, comprised mostly of rodent pests but including also significant numbers of ducks, pbeasants. song birds and rabbits at certain seasons of the year. Because they take such great numbers of rodents, house eats can be eonsidered of real benefit to farmers in the valley. Yet where game production is of primary concern, cat control cer- tainly is warranted — particularly on breeding grounds of pheasants and ducks. The 184 stomachs examined in the study actually represented 184 cat meals distributed throughout the year. Forty-one of the meals in- eluded pheasant or duck which means that a vagrant eat will average one game bird about every fifth day over the entire year, discounting the factor of carrion. In spring, when most of the game bird kills occur, the frequency must be much greater. With densities as high as a cat per 20 to 80 acres, the total loss to breeding pheasants and ducks may be locally serious. In addition there is the drain on coots and cottontail rabbits which are game speeies of lesser importance. Control measures must be handled on a local basis. On primary game areas, all eats should be eradicated if possible. The State of Califor- nia provides by law for the destruction of these predators on game refuges. Though it is advisable for farmers to maintain some house eats on their premises, limited control or restraint is necessary to keep the population of cats at a moderate level to avoid "drift" to game production areas. However, actual control of cat numbers is expensive and is complicated by sentiment and prejudice. Some people are violently opposed to any form of cat killing. Likewise control operations are sure to remove some wandering pets along with truly vagrant animals, an event which arouses additional adverse reaction. Sentiment further causes people to abandon unwanted cats rather than kill them, thereby augmenting already exist- ing vagrant populations. These considerations will always make cat con- trol difficult in the Sacramento Valley. REFERENCES Bond, Richard M. 1939. Coyote food habits on the Lava Beds National Monument. Journ. Wildlife Management, vol. ."., no. 3, p. 180-188. Bradt, G. W. 1949. Farm cat as predator. Michigan Conservation, vol. IS, no. 4, p. 23-25. Earl. John P. 1950. Production of mallards on irrigated land in the Sacramento Valley, Cali- fornia. Journ. Wildlife Management, vol. 14. no. .*>. p. 332-341'. Einarsen, Arthur S. 1942. Specific results from ring-necked pheasant studies in the Pacific Northwest. Trans. 7th North American Wildlife Conf., p. 130-146. Errington, Paul I.. 1936. Notes on food habits of the southern Wisconsin house cats. Journ. Mam- mal., vol. 17, no. 1, p. 64-65. Forbush, E. H. 1916. The domestic cat. Massachusetts State Board Agric. Econ., Bull. no. 2, LOS p. FOOD HABITS OF FERAL HOUSE CATS 189 Grinnell, Joseph 19.'i.'!. Review of the recent mammal fauna of California. Univ. Galif. Publ. Zool., vol. 40. no. 2, )». 71-234. Grinnell, .Joseph, Joseph Dixon and .lean M. Linsdale 1937. Fur-bearing mammals of California. Berkeley, Univ. Calif. Press, 2 vols., 777 i>. Grinnell, Joseph, and Alden II. Miller 1944. The distribution of the birds of California. Pacific Coast Avifauna, no. 27, COS p. Kuo, Zing Yong !!).">(). The genesis of the cat's response to the rat. Journ. Comp. Psychol., vol. 11, no. 1. ]i. 1-35. Leopold, Aldo 1931. Report on a game survey of the North Central Slates. Sporting Arms and Aimnun. Manufacturer's Inst.. 299 p. Martin. A. C, R. II. Gensch and C. P. Brown 1946. Alternative methods in upland gamebird food analysis. Journ. Wildlife Management, vol. 10. no. 1. p. 8-12. MeAtee, W. L., editor 104o. The ring-necked pheasant and its management in North America. Wash- ington, American Wildlife Inst., 320 p. McKenny, Margarel L939. Birds in the garden and how to attract them. New York, Reynal and Hitch- cock, 349 p. McMurry, Frank B. 194.1. Three shrews, Cryptotis parva, eaten by a feral house cat. Journ. Mammal., vol. 20. no. 1. p. 94. McMurry. Frank F... and Charles C. Sperry 1941. Food of feral house cats in Oklahoma. Journ. Mammal., vol. 22, no. 2, p. 185-190. Nilsson, X. X. 1940. A study of the domestic cat in relation to game birds in the Willamette Valley, Oregon. Master of Arts thesis. Corvallis, Oregon State College. Reed. Elizabeth A. 1908. Protect ins young birds from cats. Bird-Lore, vol. 10. no. 5, p. 215. Sumner. E. Lowell. Jr. 1935. A life history study of the California quail, with recommendations for its conservation and management. Pt. 2 — Conservation and management. Calif. Fish and Game, vol. 21, no. 4. p. 27i"»-;i42. Teale. Edwin W. 1945. Days without time: adventures of a naturalist. X'ew York, Dodd, Mead and Co.. 283 p. TOXICITY OF ZINC FOR RAINBOW TROUT (SALMO GAIRDNERII) 1 By Joseph R. Goodman - Former Assistant Superintendent Steinhart Aquarium, California Academy of Sciences San Francisco INTRODUCTION Difficulty in maintaining exhibits of rainbow trout (Salmo gaird- nerii) in the Steinhart Aquarium led to the suspicion that zinc from galvanized pipes might be present in the water in sufficient concentration to be toxic to these fish. Other species of trout, including eastern brook trout (Salvi I in us fontinalis) , brown trout (Salmo trutta), and lake trout (Cristivomer namaycush ), appeared able to withstand the concentration of zinc present in the aquarium waters, although their resistance may have been due to a gradual conditioning over an undetermined period of time. Actually, the concentration of zinc was not high, but it was found to be present in greater amounts than either copper or lead. The effect of zinc on fish had been noted by Abbott (1924) when he studied a case of almost total mortality of the fish in Devils Lake, North Dakota. At the time of his investigation the brook stickleback (Eucalia i neon stems) was the only surviving species and many were dying. This lake had no outlet and the total salt content was higher than normal for fresh-water lakes, but not sufficiently high to eliminate all fish on the basis of osmotic effects. However, the lake did contain 15 parts per million of zinc. Abbott tested small (unspecified) fish in a solution containing 15 parts per million of zinc (using ZnCLj). All fish died within eight hours. More recently Grindley (1946) found that rainbow trout (tialmo gairdnerii var. shasta) lost their sense of equilibrium in 133 minutes in a solution of ZnSG 4 containing 25 parts per million of zinc and died x-^vy shortly even when transferred to fresh water. Analysis of the Steinhart Aquarium water showed a concentration of zinc of from 8 to 11 parts per million. It was decided to determine experimentally whether such concentrations would be fatal to rainbow trout, and if possible discover the minimum fatal concentration. METHOD Fingerling $. gairdnerii approximately three inches long were used in all experiments unless otherwise noted. The fish were placed in all-glass aquaria, each containing approximately 17 liters of tap water. It was necessary to maintain optimum constant temperature and a high oxygen 1 Submitted for publication October, 1950. 2 At present Biochemist, Investigative Medicine Department, Long Beach V. A. Hospital, Long Beach, California. The author wishes to thank Dr. R. C. Miller, Director of the California Academy of Sciences, and Dr. E. S. Herald, Superintendent of Steinhart Aquarium, for their assistance. (191) 102 CALIFORNIA FISH AXD GAME content. Therefore, each aqiiarium was aerated by compressed air finely dispersed by a diffusion ball, and all were partly immersed in a tank of running water maintained at 11 degrees C. Inasmueh as the water in each aquarium was not circulated through a filter or allowed to be continually exchanged with fresh water, it seemed advisable to place a time limit on the measure 1 of the toxic effect of the zinc in order that the effect of accumulative toxic waste products would be minimized. For this reason 48 hours was taken as the time limit of the evaluation. However, numerous experiments were continued for five or six days before the survivors were returned to the stock tank. Varying known amounts of zinc (as ZnS0 4 ) were added from a stock solution which had been made sufficiently acid with sulfuric acid to pre- vent any zinc precipitate. Because the acid was used the pH of the test mixture was noted in the early experiments and found to vary from pi I 7.4 to pH 7.8, while the solutions of zinc near the minimal lethal concen- tration usually had a pH of 7.6. A solution of ZnCh> of similar zinc con- centration was used on one run, and produced results nearly identical to those obtained with the ZnS0 4 . Samples were taken from all solutions before the fish were added, and from almost all solutions after the fish had been removed. Zinc analyses were made on all these solutions to determine the total amount of zinc as well as to check the amount added. The dithizone method of analysis described by Hibbard (1934, 1937, and 1938) was followed. However, the dithizone was first purified by extraction with chloroform from acid solution (Offic. Agri. Chein. Assoc., 1935). RESULTS Iii a preliminary experiment three groups of 10 fingerlings each were placed in tap water (2 p. p.m. Zn) for control and in solutions con- taining 25 and 50 p.p.m. Zn, respectively. All fish exposed to 25 and 50 p.p.m. were dead in two hours. There were no fatalities in the control tank and after 48 hours these fish were returned to stock. This is in close agreement with Grindley's (1946) report that 25 p.p.m. Zn stunned and killed rainbow trout in 133 minutes. Table 1 shows the results of a second series in which 10 trout were used per aquarium. Six parts per million was fatal. TABLE 1 Survival of Three -inch Rain aow Finger lings Zn p.p.m. Number alive out of 10 original at — 14 hours 18 hours 24 hours 2 10 3 10 10 6 : 10 14 In a third group fish which were about six months old and approxi- mately five inches in length were used. They had been in the aquarium water system for about 40 days. At that time the aquarium water tested 2 p.p.m. Zn. As these fish were a little larger, only five specimens were placed in each tank. Table 2 shows that some of these survived 6 p.p.m. TOXICITY OF ZINC FOR RAINBOW TROUT TABLE 2 Survival of Five-inch Rainbow Fingerlings 193 Zn Number alive out of 5 originals at — p.p.m. 12 hours 24 hours 48 hours 2 5 4 1 5 2 5 6 2 10 It is realized that the increase in tolerance over that shown in Table 1 could have been due to 40 days' acclimatization in the aquarium at 2 p.p.m. Zn or to the larger volume of water per fish. A series of experiments was run to determine whether the young- fish developed a tolerance with increasing age. For this purpose eyed eggs were obtained, and were hatched in the aquarium in water which tested 1 p.p.m. Zn. Table 3 shows the effect on trout 10 days to two weeks old. At this age they had just completed the absorption of the egg sac. Under these conditions 4 p.p.m. was fatal to 90 percent and 3 p.p.m. fatal to 55 percent. TABLE 3 Survival of 10-14-D ay-Old Rainbow Fingerlings Zn p.p.m. Number alive out of 20 originals at — 1 6 hours 40 hours 48 hours 1 20 III 16 5 20 13 2 20 3 11 4 2 6 TABLE 4 Survival of Four- Week -Old Rainbow Fingerlings Zn Number alive out of 20 originals at — p.p.m. 18 hours 24 hours 42 hours 48 hours 1 20 20 If) 18 20 18 18 8 20 15 6 3 20 2 _ 15 4 . 2 6 .. 1 TABLE 5 Survival of Eight- Week-Old Rainbow Fingerlings Zn Number alive out of 20 originals at — p.p.m. 18 hours 30 hours 45 hours 66 hours 1 20 20 20 18 20 20 20 15 20 19 19 7 20 2 19 4 18 6 4 194 CALIFORNIA FISH AND GAME TABLE 6 Survival of 10-Week-Old Rainbow Fingerlings Zn p.p.m. Number alive out of 20 originals at 22 hours 27 hours 30 hours 48 hours 1 20 20 20 15 20 20 20 11 20 20 20 9 20 2 20 4 20 6 -_- 2 At four weeks their tolerance had increased as shown in Table 4, while the tolerance of fish from the same batch of eggs at 8 and 10 weeks (Tables 5 and 6) had increased so that all the fish eventually survived in 4 p.p.m. Zn for 48 hours. Many of the survivors of the 4 p.p.m. Zn solution showed strong toxic symptoms and could be picked up by hand. Some of these subse- quently died, even though they were transferred to fresh water. Many of the young fish that died in this scries of experiments devel- oped bent backs while in the zinc solutions. Sometimes this would occur as a single 90-degree bend; sometimes it took the form of a "crick" or a more pronounced "S" shape. Both the young fry and the fingerlings in many instances acted as though they were in a stupor and could easily be picked up by hand. They would often have tremors or pronounced twitching when handled. At other times they were highly excitable and at the least disturbance would dart head-on against the wall of the aquarium. They would do this even in the larger tanks with opaque walls, indicating that such behavior was not due to the invisibility of the glass aquaria. Some fish were noted to have a marked fading of color along the lateral line. This and the other symptoms tend to suggest that the nervous system was being affected by the zinc. CONCLUSION Zinc at a concentration of six parts per million was fatal to fingerling rainbow trout (Salmo gairdnerii) on exposures of 48 hours or less. Young fish two and four weeks old could not tolerate concentrations of four parts per million, but with increasing age showed a tendency to develop a tolerance to solutions of this concentration. LITERATURE CITED Abbott, G. A. 1924. A chemical investigation of the waters of Devils Lake, North Dakota. Indiana Acad. Sci., Proc. 40th Ann. Meet., vol. 34, p. 181-184. Grindley, J. 1946. Toxicity to rainbow trout and minnows of some substances known to be present in waste water discharged to rivers. Annals of App. Biol., vol. 33, p. 103-112, 4 figs., 3 tables. Hibbard, P. L. 1934. Micromethods for determination of zinc. Indust. and Eng. Chem., vol. 6, anal, ed. no. 6, p. 423. 1937. A dithizone method for measurement of small amounts of zinc. Indust. and Eng. Chem., vol. 29, no. 11, p. 127-131. 1938. Estimation of copper, zinc and cobalt (with nickel) in soil extracts. Indust. and Eng. Chem., vol. 30, no. 39, p. 615-618. Official Agricultural Chemists Association 1935. Official and tentative methods of analysis of the Association of Official Ag- ricultural Chemists, 4th ed., p. 378. TOXICITY OF THE ROE OF THE CABEZON, SCORPAENICHTHYS MARMORATUS 1 By Carl L. Htjbbs and Arne N. Wick Scripps Institution of Oceanography (University of California) and Scripps Metabolic Clinic An unhappy gastronomic experience of the senior author and his wife and laboratory experiments by the junior author indicate rather definitely that there is some toxic constituent in the roe of the cahezon, Scorpat nichthys marmoratus Girard, a large cottid fish of western North America. On .January 14, 1!>23, a ripe adult female cahezon, 440 mm. in standard length, caught during the day in a tidepool on Point Lobos, Monterey County, California, was eaten for supper. The senior author and his wife partook of the roe while her parents and a young child ate the flesh. Those who ate the flesh were not discomforted in the least, nor have we heard of anyone having been poisoned by eating this common food and game fish. The two who ate the eggs awoke in misery about four hours afterward and were violently ill throughout the rest of the night, with rapidly alternating chills and fever and with frequent vomiting and diarrhea. There was, however, no marked prostration, fainting, dizziness, or paralysis. Both were left very w T eak in the morning but gradually recovered during the day, with no residual or recurrent symptoms. No medical attention was received. This experience, related to fellow ichthyologists, was the basis for the statement by Walford (1931, p. 127), that "although the flesh is of excellent quality the roe is said to be poisonous," and for the following remarks by Schultz (1948, p. 68) : "Also, it is definitely known that the eggs of certain fishes are poisonous, although the fishes themselves are not. (Dr. Hubbs became very sick after eating some eggs of a United States Pacific Coast marine sculpin.) " When a very large female collected at the Scripps Institution reef by Jack Prodanovich on December 23, 194f), was found to be full of nearly ripe roe, a long desire for an experimental test of the toxicity of the roe w r as reactivated. The ovaries were promptly hard-frozen. They were kept in that condition for nine months, until the experiments were run. The experimental results (Table 1) confirmed the experience re- counted above. A portion of the roe (77 g.) and 50 ml. of water were homogenized for five minutes in a Waring Blendor. The mixture was fed orally to 12 male albino rats and to two guinea pigs. The animals had in addition their regular food at all times. Pour rats and one guinea pig 1 Contribution from the Scripps Institution of Oceanography, New Series, No. 506, and from the Scripps Metabolic Clinic. Submitted for publication, November, 1950. (195) 196 CALIFORNIA FISH AM) GAME TABLE 1 Data on Toxicity of Cabezon Roe to Rats and Guinea Pigs Animal Weight of animal Weight of roe administered Death time Grams Percent body wt. (hrs.) Rat... 330 420 7.7 7.7 2.33 1.83 22 22 272 1.43 0.53 84 291 1.43 0.49 314 1.07 0.34 318 1.07 0.34 326 0.71 0.22 76 343 0.71 0.21 292 0.36 0.12 302 0.36 0.12 338 0.18 0.05 350 0.18 0.05 -- (juinea Pig 355 400 1.43 1.43 0.40 0.36 30 died. All the animals exhibited diarrhea and nasal discharge, but these conditions diminished in intensity as the dose was decreased. It would obviously be unwise to eat the roe of the cabezon, but there is no indication that the flesh of this fish is in any way harmful. REFERENCES Schultz, Leonard P. (with Edith N. Stern) 1!»4N. The ways of fishes. D. Van Nostrand Co., Toronto, New York. London, xii + 264 p., illustr. Walford, Lionel A. 11131. Handbook of common commercial and same fishes of California. Calif. Div. Fish and Game, Fish Bull. 28, 181 p., illustr. YIELD OF HATCHERY TROUT IN CALIFORNIA LAKES 1 By Brian Curtis 2 INTRODUCTION What happens to hatchery trout after they are liberated? How many survive to be caught by fishermen ? It is recognized that lakes as a class produce different results from streams, and also that there are differences between lakes and between streams. In California, stream investigations have not yet reached the point where they provide a broad picture, but lake studies have been in process for the last 10 years. Some of these have been published in this periodica], but others have seen the light of day only in the form of ad- ministrative reports. Most of them are, for one reason or another, now terminated, and the time lias come to bring all this material together and make it available to sportsmen and conservationists. In a state as large and as geographically diversified as California, experiments of this nature must be performed in different areas, under different conditions of climate and fishing intensity, and with different kinds and sizes of trout. For this reason the results are sometimes confus- ing. Having had general supervision of most of this work, and being therefore more familiar with the interrelationships of its different phases and with their relative strength and weakness than any other one person, it has fallen to me to undertake the task of evaluation and synthesis; but major credit belongs to the men who were directly in charge of the various projects, and especially to J. H. Wales, Elden H. Vestal, Harry A. Han- son, Garth I. Murphy, J. C. Praser, and Scott M. Soule, all of the Bureau of Fish Conservation of the California Division of Fish and Game. The period covered by this report is approximately the decade from 1!)4() to 1950. The number of lake studies is nine, of which six are con- sidered important enough to be reviewed in some detail here, while the other three are treated together in one section. Most of these lakes have no, or insufficient, natural spawning facilities. The method throughout has been to plant a known number of trout, and to find out, by complete catch records, by sampling the catch, or in other ways, how many of these fish were caught. Marking through the removal of one or more fins has been relied on to a large extent for identification of the fish. In earlier years it was assumed that fish with one or two fins missing suffered on the average no greater mortality than intact ones. More recently this assumption has come to be doubted, and experiments on salmon fingerlings have sup- ported this doubt. However, the life history of most trout is quite dif- ferent from that of salmon, and two experiments in California on marked 1 Submitted for publication October, 1950. 2 Formerly of the Bureau of Fish Conservation, California Division of Fish and Game. i 197 ) L98 CALIFORNIA FISH AND GAME trout have produced conflicting results. Pending further evidence, we shall have to withhold judgment, and stick to the assumption that fin marking docs not significantly impair the viability of trout, at least in lakes in California. It must be remembered that throughout this report we are dealing with yield to tin angler, which is quite different from true survival. The latter is inevitably higher: from any group of planted fish there remain in any year an undetermined number still in the water after the anglers' total catch has been counted. And it must be remembered that two factors having nothing to do with survival affect the yield to the angler. One is stocking intensity, the other fishing pressure. Heavy stocking in a lightly fished lake will result in low yield combined with high quality of fishing (measured in terms of numbers of fish caught by each angler). Light stocking in a heavily fished lake will produce high yield combined with poor fishing. Optimum results from the point of view of both yield and angling quality are obtained when stocking and fishing pressure are properly balanced. We shall proceed now to review the experimental work on the differ- ent lakes in as brief a manner as possible while at the same time including the details and the circumstances necessary for an understanding of the results, and then shall try to fit the various pieces together into a gen- eralized picture. CASTLE LAKE, SISKIYOU COUNTY This Northern California lake has been the subject of one of the longest intensive creel counts carried out on any body of trout water in the United States. Two reports have already been published ( "Wales, 1946, 1947) and more will undoubtedly follow. Its features are: Elevation : 5,200 feet. Area : 47 acres. Figure 91. Castle Lake, looking' northeast toward Mt. Shasta. Photograph by J. H. W T ales. YIELD OF HATCHERY TROUT 199 Depth : 120 feet. Volume : approximately 1,800 acre-feet. Winter conditions : snow and ice for five to six months. Spawning : successful only for lake (mackinaw) trout, and for east- ern brook trout in bottom spring 1 seepages. There are no permanent camps on the lake and only one access road. A full-time employee was stationed there throughout the major part of each season, with the work on a part-time basis only in the very early and late days, when little fishing is done. The record, therefore, is to all in- tents and purposes a complete creel census. The experiment has two distinct parts. During the first, fingerlings of three species, rainbow trout (Sal mo gairdnerii), brown trout (Sal mo trutta), and eastern brook trout (Salvelinus fontinalis) were planted in equal numbers to study their relative merits. Occasional small plants of larger trout were made to improve the fishing and thus bring in more anglers. Also present in the lake was a small population of lake trout (Cristivomcr namaycush) , remnants of a stock introduced in 1924; a small population of the western golden shiner (Notemigonus crysoleucas auratus), presumably introduced at about the same time as the lake trout; and a few speckled dace (Rhinichthys osculus), first noticed in the lake in 1945 and presumably brought in by anglers as bait. This part of the project came to an end when all fish were killed through chemical treatment of the lake in October, 1946. Since then only one species has been planted, the eastern brook trout. Each year class of trout was identifiable either because fins had been removed before planting, or because it was left unmarked and was the only significant group of such fish in the lake during its lifetime. It was thus possible to follow the progress of each year class through the fishery, and observe the percentage yield of each in relation to the size of the fish when planted. Fish stocked as yearlings showed, as is to be expected, a much higher yield than fmgerling plants; but as between different sizes of fingerlings the correlation between yield and size at planting was poor. For example, rainbow planted at 37 per ounce (about 1| inches) yielded 4.2 percent, while those planted at 7 per ounce (3 inches) yielded only 2.6 percent; still another year class planted at 10 per ounce yielded 7.2 percent. These records have been published in detail (Wales, 1946, 1947 ) and will not be reprinted here, where we shall try to give consideration only to the major outlines. Wales has shown that in the first phase of the Castle Lake project fmgerling plants of brook and rainbow trout played their most important part in the catch as yearlings. Since catch records did not begin here until 1941, plantings of these species prior to 1940 are eliminated from Table 1, as are also, of course, catches of fish from these year classes. Since brown trout, as shown by Wales, continue to enter the catch in significant numbers for as long as six years, brown trout plantings as far back as 1938 are included in Table 1. In considering the 3.6 percent average yield for the first phase (Table la) it must he remembered that when the lake was chemically treated in October, 1946, it still contained many fish which would have been caught in succeeding years. This is especially true of the brown trout, of which 1,960 individuals were by actual count picked up after the chemical treatment. Based on the detailed records of the earlier years 200 CALIFORNIA FISH AND GAME TABLE 1 Castle Lake Finger-lings a. Catch Records from 1941 to 194<>, Inclusive (First Phase) Trout planted Numbers caught from 11141 to 1946, incl. Species Size Years "(incl.)" Number Yield (percent) Number per ounce Length in inches Eastern brook_ Rainbow. Brown 6 to 34 5 to 37 6 to 31 1^-3 1J4-3 1940-45' 1940-45' 1938-45 48,000 48,300 61,500 817 1,834 2,968 1.7 3.8 4.8 157,800 5,619 Average: 3.6 b. Catch Records from 1947 to 1949, Inclusive (Second Phase) Trout planted Numbers caught through July 31, 1950 Species Size Years Number Yield (percent) Number per ounce Length in inches Eastern brook.. Eastern brook. . 5.0 12.5 3 2 1947 1948 20,000 20,000 5,419 4,686 27.1 23.4 111,1)011 10,105 Average: 25.3 1 Plants before 1040 not shown because not entering catch records In significant numbers. (Wales, 1947) , it is conservative to estimate that if the lake had not been chemically treated at least 600 more fish would have been caught from the plantings listed, which would have brought the over-all yield up to approximately 4 percent. This is with stocking at the average rate of 20,000 fingerlings per year, and fishing pressure at 596 angler-days, equivalent to 425 fingerlings and 13 angler-days per acre per year. Fish- ing success, including the yearlings and the lake trout, averaged close to 0.6 fish per hour over the period. For the second phase of the experiment (lower part of Table 1 ) the records available at this writing carry us only through July 31, 1950. The yield of 27.1 percent from the five-per-ounce (three-inch) brook fingerlings is extraordinarily high even after making allowances for the fact that the only other fish in the lake at the time of their planting were the six-inch yearling brooks planted in July of the same year (Table 2). For the smaller brook fingerlings planted in 1948 the yield already reaches 23.4 percent, and if their pattern at all follows that of their predecessor class their yield may be even higher. At present, average yield for the two year classes stands at 25.3 percent. It is of interest to note here the difference between the first, three-species phase of the experiment, with lake trout also present, when the brook fingerlings furnished their best fishing as yearlings, and the second, single-species phase, when they still play an important part in the fishery in their fourth year. The increase in over-all yield is nothing short of phenomenal. YIELD OF HATCHERY TROUT 201 Fishing pressure in the first three years of the second phase averaged 1,051 angler-days per year (22 angler-days per acre), and fishing success over 1.6 trout per hour — very markedly above the first phase. The high rate might be attributed in part to the 20,000 yearlings planted in 1947 to make fishing possible the first season after the chemical treatment; but in 1949, when this group provided only 8 percent of the catch, trout were caught at the rate of 1.8 per hour — higher than in 1948 when the yearlings formed 66 percent of the total. Stocking of fingerlings was at the rate of 20,000 per year in 1947 and 1948 — 125 per acre — the same as in the first phase of the experiment. TABLE 2 Castle Lake Yearlings a. Catch Records from 3041 to 1046, Inclusive (First Phase) Species Eastern brook Rainbow Brown. Trout planted Size 6 to 16 per lb. 24 per II). to 1 .4 lbs. eaeh 10 to 24 peril). Years I'M:' 1943 1 1946 1 119421 11943/ (1942 11943 Number 3,100 3.300 2,700 9,100 Numbers caught 719 905 865 2,489 Yield (percent! 23.2 27.4 32.0 Average: 27.4 1 b. Catch Record from 1!>47 to 1!>4!), Inclusive (Second Phase) Species Trout planted Numbers caught Yield Size Years Number (percent) Eastern brook . 13.3 per lb.... 1947 20,000 9,541 47.7 To turn to the yearlings (Table 2), their over-all yield of 27.4 per- cent in the first phase of the project is low. This may be due to their small numbers, running from 2,000 to 4,000 in the years when they were planted ; to the comparatively light fishing — averaging from three to four fishermen per day on the lake throughout the six years; and to the num- bers of fingerlings planted at the same time. In any case, the yield of 47.7 percent from the 20,000 yearling brooks stocked in 1947 at the beginning of the second phase comes close to what one may be permitted to consider the norm, in spite of two unfavorable factors : an abnormally large number of these fish were found dead in the lake during the first season, and at its end over 1,000 of them are known to have gone out of the lake into the outlet stream, presumably not to return. FROG LAKE, NEVADA COUNTY Frog Lake, like Castle Lake, lies in a granite cirque basin. Although at a higher elevation, it is some 200 miles farther south and subject to 202 CALIFORNIA FISH AXD GAME much the same climatic conditions. It is some 12 miles from the town of Truckee, and has only one access road. Its features are: Elevation : 7,900 feet. Area : 33 acres. Depth : 45 feet. Winter conditions: snow and ice for five to six months. Spawning : successful for brook trout only in bottom spring seepages. The experiment began with an incomplete catch record in 1938. From then through 1918 records were maintained on a careful basis through the courtesy of the late Mr. Felix Smith, owner of the lake, who had his caretaker do this work ; but since the man had other duties to perform he could not be expected to cover all anglers. It is estimated that the records are not over 80 percent complete. Since they have not been published before they are printed in summary here (Tables 3, 4, 5). TABLE 3 Frog Lake Stocking Record, 1937-1947 (All Fish Were Fingerlings) Year Number planted Eastern brook Rainbow Brown Totals 1937 5,000 5,000 4,000 5,000 7,000 5,000 4,500 1 5,000 4,000 5,000 7,000 5,000 15,000 15.000 14,000 15,000 15,500 9,500 10,000 1 2 000 1938 1939 4,000 5,000 7,000 5,000 1940 15,000 21,000 15,000 15,000 15 000 1941-. 1942... 1943 1944 1945 14,000 15,000 15,500 1946 1947 Totals Ml. 105,000 21,000 157,000 1 Steelhead stuck. TABLE 4 Summary of Trout Caught in Frog Lake, 1938-1948 Eastern brook Rainbow Brown All species Year Number Percent Number Percent Number Percent Total caught of total caught of total caught of total number 1938 183 65 9 3 89 32 28H 1939 572 73 50 6 160 21 782 1940 515 72 72 10 125 18 712 1941 305 65 64 13 103 22 472 1942 221 42 65 12 246 46 532 1943 122 24 106 21 284 55 512 1944 88 22 49 12 263 66 400 1945 __ 65 18 80 22 221 60 366 1946 91 25 62 17 210 58 363 1947 128 30 85 20 218 50 431 1948 99 22 130 29 216 49 445 Totals 2,389 45.1 772 14.5 2,135 40.4 5,296 1 Catch record in 1938 was only partial. YIELD OF HATCHERY TROUT 203 TABLE 5 Frog Lake: Yearly Comparisons of Fishing Year Number of reporting anglers Total reported catch Average catch per angler-day Average catch per hour 1938' • 53 L'Sli 271 190 221 166 134 183 280 203 266 281 782 712 472 532 512 400 366 363 431 445 5.3 2.7 2.5 2.5 2.1 3.1 3.0 2.0 1.3 2.1 1.7 0.93 1939 0.81 1940 - 0.58 1941 0.68 1942 0.58 194.3 0.61 1944 0.64 1945 0.51 1946 0.37 1947 0.56 1948 0.44 1 Catch record in 1938 was only partial. Many "zero catches" went unrecorded, thus bring- ing up the catch per angler-day and per hour. It will be seen (Table 3) that from 1939 through 1942 three species of fingerling trout were planted in equal numbers, as at Castle Lake. Thereafter only rainbow fingerlings were planted, but quantities of eastern brooks and browns still remained in the lake. That an unauthor- ized plant of brown trout was made prior to 1939 is evident from their appearance in the catch in 1938 and 1939 (Table 4). Because there is no record of these fish they do not appear in Table 3. A few hundred trout w r ere marked in 1940 for age-length assess- ment, and some in 15)47 which played almost no part in the total catch, but the great majority of the planted fish were left unmarked because of the fact that the caretaker did not have time to examine and record marks. To arrive at a valid approximation of the yield in Frog Lake certain adjustments must be made. With regard to the eastern brook, we must adjust for the not inconsiderable natural spawning. In the first phase at Castle Lake brook trout played no significant part in the catch beyond their third year after the year of planting. Since none were planted in Frog Lake after 1942, we must assume that those caught after 1945 were naturally produced, and eliminate them from the count before computing the yield. Furthermore, we know that some of the brooks caught in the earlier years were naturally produced. From 1946 through 1948 naturally produced brooks were caught at the rate of around 100 a year ; we can therefore hardly do otherwise than assume that on the average the same was true from 1938 through 1945, and that some 800 nonhatchery brook trout were caught in those years. The recorded catch for those years was 2,071 brooks. From this must be deducted 800 nonhatchery fish, leaving 1,271. Therefore, the total hatchery stocking from 1937 to 1942 of 31,000 eastern brook fingerlings yielded 1,271 fish to the angler, or 4.1 percent. Since a higher yield (4.4 percent) would be obtained by applying the same process to the assumption that all brooks caught after 1944 were naturally produced, the figure of 4.1 may be considered to be on the con- servative side. For the rainbow, with no natural spawning, no adjustments are necessary. From 1937 through 1947, 105,000 of them, including the 4,500 steelhead of 1937, were planted; 772 were caught from 1938 through 204 CALIFORNIA FISH AND GAME 1948 ; yield was 0.7 percent. That the rainbows which were placed in this lake did not do well here is an inescapable conclusion, and there is some reason to suspect that the fall-spawning stock largely used here is not well suited to fingerling planting in high mountain lakes. For the brown trout, adjustments again are necessary, even though successful natural spawning did not occur. We have no record of stocking prior to 1939, and we know from the Castle Lake work that browns play their most significant part in the catch as two-year-olds. If, then, we elimi- nate from the catch all browns caught in 1938, 1939, and 1940, we are certainly on the conservative side, for any survivors of the earlier unau- thorized plant lingering on to be caught in 1941 and thereafter would be more than offset by survivors of the hatchery plants lingering to be caught after the records were brought to a close in 1948 (and the length of life of the browns here, corroborating the experience in Castle Lake, is noteworthy). Total catch of browns from 1941 through 1948 was 1,545 ; total plantings were 21,000; yield to the angler 7.7 percent. This seems a high figure for brown trout in a mountain lake, and perhaps not to be expected unless other species are present for them to feed on. Summarizing our adjusted figures, we have the vield shown in Table 6. TABLE 6 Frog Lake: Yield of Fingerling Trout, Adjusted Figures Species Number planted Number caught Yield (percent) Eastern brook _ 31,000 105,000 21,000 1,271 772 1,545 4.1 Rainbow. Brown. 0.7 7.7 157,000 3,588 2.3 With regard to the over-all yield of 2.3 percent, two observations must be made. The first is that this figure is based on an estimated 80 percent catch record, so that the figure for 100 percent of the catch would be 2.9 percent. The second is that, included in this figure and pulling it down, is the abnormally poor showing of the rainbows, which constituted the bulk of the plantings. The stocking over most of the period has run about 15,000 a year, or at the rate of 450 trout per acre ; the fishing pressure has averaged 220 angler-days per season, or about seven anglers per acre ; and the catch has run from a high of 0.8 to a low of 0.4 fish per hour, with a mean of less than 0.6. JUNE LAKE, MONO COUNTY The principal features of June Lake, on the east slope of the Sierra, are : Elevation : 7,600 feet. Area : 310 acres. Depth : 140 feet. Winter conditions : snow and ice for four to five months. Spawning : none successful for rainbow trout. YIELD OF HATCHERY TROUT 205 Figure 92. Fishing boats on June Lake, May 30, 1940. Photograph by Elden H. Vestal. This lake is much more accessible than either Castle or Frog, is sur- rounded with resorts and homes, and is therefore not susceptible to a complete creel count. Records, however, have been complete enough to permit reliable estimates. From 1939 through 1941 the creel counts were made under professional supervision by CCC boys, ERA assistants, and boat concessionaires ; in 1942 reliance was placed on intensive sampling of the catch. The methods whereby estimated total catches were derived from partial records and samples have already been printed (Vestal, 1943), and we shall therefore limit ourselves to setting forth the results. Fishing in June Lake, once excellent, had declined until ' ' catchable- sized" rainbow of fall-spawning stock were planted in 1937. Remnants of these fish and of the similar 1938 plant undoubtedly contributed to the 1939 catch ; but, by the same token, remnants of the fish planted from 1939 through 1942 undoubtedly still remained in the lake to be caught in later years after this experiment ended. The two groups thus compensate for each other, and the yield obtained by dividing the total number of fish planted in the four years by the fish caught is if anything on the low side due to the heavier plantings in the later years. It will be noted ( Table 7 ) that the number of fish actually counted during the first three years, 64,699, gives a yield of some 31 percent of the number planted. This is a rock bottom figure. If we take the estimated catch for the three years, a figure derived in perhaps a somewhat arbi- trary manner, we get a yield of nearly 45 percent. If with this is com- bined the estimate for 1942, very carefully derived from a very careful sample, the yield is about 48 percent. We have, therefore, from spring plantings of catchable rainbow trout at the average rate of 250 per acre 4—39247 206 CALIFORNIA FISH AND GAME in a lake where fishing- pressure averages 40 angler-days per acre each season and the catch 0.6 fish per hour, a yield of not less than 31 percent, and of probably as high as 48 percent. TABLE 7 Stocking and Catch Records in June Lake, 1939-1942, Inclusive (All Fish Were Rainbow Trout of Fall-spawning Stock) Catch Stocking Recorded Estimated total 1939 70,000 at 2 . 6 per oz. (4 in.) stocked 5/26/39 _ . _ . 16,452 19,476 28,771 26 000 1940 70,000 at 1.3 per oz. (5 in.) stocked 6/19/40. _ _ 29,000 1941 70,000 at 1. 2 per oz. (5 in.) stocked 5/22/4 1 . . 39 000 210,000 6 1.699 30.8 Sample only: 3,536 94,000 44 8 1942 100,000 at 13.5 per lb. (6 in.) stocked 4/29/42 56,000 310,000 150,000 48 i GULL LAKE, MONO COUNTY Gull Lake adjoins June Lake. Its features are: Elevation : 7,600 feet. Area : 68 acres. Depth : 64 feet. Volume : 2,500 acre-feet. Winter conditions : snow and ice for four to five months. Spawning : successful for eastern brook trout in small tributaries. The lake was treated with rotenone in 1940 (Vestal, 1942) to elimi- nate an enormous population of rough fish (Siphateles bicolor obesus). It was to evaluate this operation and the subsequent stocking with east- ern brook front that creel counts were made. With no natural spawning before the fall of 1941, all fish caught through 1942 were inevitably hatchery trout. TABLE 8 Gull Lake Stocking and Catch Records, 1940-1942 Stocking : Yearling brook trout, 1.3-1.1 per oz. (about 5 in.) Nov. 1940: 78,000 Fingerling brook trout, 3 per oz. (about 31 in.) Aug. 26, 1941: 20,000 Catch Yearlings Fingerlings Recorded Estimated Recorded Estimated 1941 5,113 10,327 10,000-15,000 17,000 1942 46 530 Yield (percent) 15,440 19.7 27,000-32,000 34.6 41 2.7 YIELD OF HATCHERY TROUT 207 Figure 93. Gull Lake looking' southwesterly. Photograph by Elden H. Vestal, July, 1940. The estimate of the yearling catch in 1941 (Table 8) does not rest on a very firm foundation, and to be on the safe side the lower figure, 10,000, should be used. The estimate of 17,000 of these fish caught in 1942 may be taken with considerable confidence, thus giving 27,000 as a con- servative estimate of the total number caught in two years, and a yield of about 35 percent. This seems far from satisfactory in view of the heavy stocking — at the rate of 1,150 yearlings per acre; but it must be remembered that these 78,000 brook trout were planted in November at a size of five inches in a lake which, having just been chemicaly treated, was low in fish food, whereas "catchable fish" as we usually think of them are planted at a size and time when they will enter the fishery almost immediately. The estimate of the catch of the fingerlings planted in 1941 is based on examination of a sample of 1,524 fish caught in 1942. These were allo- cated to year-classes: 3,405 to the 1940 yearlings and 119 to the 1941 fingerlings, by sight classification based on length. However, only 23 of the observed fish were fin-marked, and one-half of the 1941 fingerlings had been so treated. On this basis it is logical to suspect that only about 46 of the "fingerlings" actually belonged to that class, and that the rest of the 119 were small fish of the 1940 yearling group. To be on the con- servative side, this is the assumption which has been adopted here, and results in the estimate of 530 of the 1941 fingerling plant having been caught in 1942 for a yield of 2.7 percent. If the pattern of Castle Lake after treatment recurred here, there would be at least as many of these fish caught the following year, with a yield of over 5 percent. Unfortu- nately, record-taking had to be suspended due to the war. 208 CALIFORNIA FISH AND GAME In 1941 estimated fishing pressure averaged in the neighborhood of 30 anglers per acre and catch 1.3 per hour ; in 1942 the respective figures were 50 per acre and 1.2 per hour. Stocking in 11)40 was at the rate of 1,150 yearlings per acre; in 1941 at the rate of nearly 300 fingerlings per acre. CRYSTAL LAKE, LOS ANGELES COUNTY This project had fewer complicating factors than any of the others. and its results are therefore the easiest to interpret. Its features are : Elevation : 5,500 feet. Area : 10 acres. Depth : 48 feet. Volume : 335 acre-feet. Winter conditions : snow and ice for several months. Spawning : none. Close enough to Los Angeles to attract multitudes of fishermen, this lake had provided a satisfactory fishery until introduced goldfish (Caras- sius auratus) and chubs (Gila orciittii) overran the trout. In the fall of 1941 all fish were killed with rotenone. Restocking took place in January and February, 1942, with 14,000 rainbow trout averaging from 9 to 13 to the pound. The season opened May I. Fishing pressure was intense, and from May 15 to August 21 close to 26,000 additional rainbows, averaging from six to the pound to 24 to the pound, were placed in the lake. Due to the interest and the excellent work of William E. Conner, owner of the single camp and boat concession at the lake, the catch records are highly reliable and about as complete as is practically possible. They show that 28,500 trout were caught, out of the 39,800 planted, making the yield 71.6 percent. Pishing pressure of 6,822 angler-days is at the prodigious rate of 682 angler-days per acre for the season ; and in spite of the fact that the catch averaged just under one fish per angler per hour — a very satisfactory figure — 28 percent of all the angler-days produced no trout! About 10 percent of the angler-days resulted in catches of over 15 trout — the limit at that time being 25. Stocking averaged 3,980 catchable fish per acre. This would, of course, not have been possible but for the fact that the fish were being constantly removed and replaced throughout the season. In fact, this was purely a "put-and-take" proposition; but that such a system, although expensive, does yield to the angler a high percentage of the trout planted is clearly demonstrated. LAKE ALMANOR, PLUMAS COUNTY This power storage reservoir in Northern California inundates a small natural lake and a large forested meadow from which the trees were not removed when the dam was built, Its features are : Elevation : 4,500 feet, Area : 28,000 acres at maximum allowable level. Depth : 120 feet in one spot, but not more than 30 feet over most of the lake bottom. Volume : 1,600,000 acre-feet at maximum allowable level. Winter conditions : frozen for four months. Spawning : excellent for rainbow in many tributaries. YIELD OF HATCHERY TROUT 209 Ever since the clam was completed this lake has been noted for the rapid growth and large size of its rainbow trout. Even now when, accord- ing to old-timers, fishing is no longer what it used to be, the rainbows average from 2\ to 2| pounds. Water temperatures become high in sum- mer, and the front then concentrate in the cold sub-surface springs. Largemouth black bass (Micropterus salmoides) have found their way into the lake; the noticeable increase in their numbers in the last two years leads to the surmise that this may become a good bass lake. In spite of the excellent spawning .tributaries, there has always been a strong demand for the planting of fingerling trout here. Marking experiments have been undertaken, mainly in the hope of finding out what contribution these hatchery fish were making to the catch. Returns have been difficult to obtain because of the number of boat landings and of the road which encircles the lake. Marked fish planted in 1942 and 1943 gave no usable returns. In June and July of 1946, 100,000 marked rainbow were planted at 12.8 per ounce (two inches), and in August and Septem- ber of 1947, 73,800 at 6.6 per ounce (three inches). 114,000 unmarked rainbow were also planted in 1947 at 25 per ounce (one and three-quarter inches), but play no part in this project. Prom the 1946 plant. 64 returns have been officially recorded; from the 1947 plant, seven. It is the care- fully considered opinion of the trained men in charge of this work that the total catch numbers about six times the officially recorded catch. On this basis the 1946 plant of 100,000 has contributed 384 fish to the creel for a yield of 0.4 percent ; the 1947 plant of 73,800 has contributed 42 fish to the creel for a yield of 0.06 percent. Average yield for the two plants is therefore 0.23 percent. But even if we disregard the 1947 fish on the theory that something went abnormally wrong with them either before or after planting, we are faced with a yield in the order of magnitude of one- half of one percent from the 1 946 fish as the best known contribution of hatchery fingerlings to fishing in Lake Almanor. That fingerling planting has helped fishing very little in a lake so large and so well furnished with natural spawning facilities as this one will not come as a surprise to those who have studied such matters. The number of fisherman-days on Lake Almanor is estimated at around 30,000 in 1948 and 1949, with the total catch each year in the neighborhood of 10,000 — mostly wild fish, needless to say. OTHER LAKES Creel counts on the three lakes in this section have been much less intensive than in the six previously discussed, and the yield figures can not therefore be considered to have the same degree of reliability. Conn Valley Reservoir, Napa County, impounds the waters of Conn Creek and its tributaries which, prior to the construction of the dam in 1945, received runs of steelhead trout from the ocean via Napa River and San Francisco Bay. When full, at an elevation of 315 feet, it contains 31,000 acre-feet, with an area of about 800 acres and a depth of 110 feet. Winters are comparatively mild, with much rain but no ice. Good gravels in w r hich steelhead formerly spawned exist in the very small tributary streams, but the latter become extremely low and often inter- mittent in late summer. 210 CALIFORNIA I is I I AND GA \l 1 ■', Although planted exclusively with rainbow trout because of local sentiment centering- around the now defunct steelheacl runs. Conn is not a favorable trout habitat. The surface water becomes warm in summer- as high as 78 degrees — and the lower levels with cooler water become deficient in oxygen. Green sunfish (Lepomis cyanellus), strayed into the reservoir from ponds higher in the watershed, and Pacific lampreys (Entosphcnus tridentatus ) which appear to have become landlocked, are not helpful to the trout population. The City of Napa, owner, has restricted the daily catch to 10 fish, and in some years has imposed a shortened season. A creel count has been made by the Division of Fish and Game at the opening of the season each year since fishing started in 1947, and the city employees at the boat landing have kept excellent records of fish brought in throughout the season. These two sources, plus an estimate arrived at by the city and division employees of the ratio between total boat catch and total shore catch, form the basis for the estimates of total catch. The planting record is given in Table 9. TABLE 9 Rainbow Trout Planted in Conn Valley Reservoir From Its Construction to End of 1949 Fishing Season Date Number Size 1946, April 1947, May Summer.. _ _ _ __ _ .. 1948, March.. 100,000 100,000 43,000 20,100 41,400 25 per oz. (2 inches). Unmarked. 22 per oz. (2 inches). Unmarked. Fingerlings rescued from tributary streams and placed in reser- voir. Unmarked. 6 to 10 per lb. (6 to 8 inches). 1,000 marked. 1949, April 12 to 16 per lb. (5 to 6 inches). Unmarked. Catch recorded during the 61-day 1947 season was 5,515 ; total catch was estimated at not less than 7,000 as an absolute minimum, with 11,000 considered a more probable figure. Study of 100 scale samples indicated that 30 percent of the fish were of hatchery origin. Applying this figure to the estimates, not less than 2,100 and more probably about 3,300 hatchery fish were caught from the 100,000 fingerlings planted in April 1946, making a yield of 2.1 to 3.3 percent — or, if one wishes to average the two estimates, the yield could be called 2.7 percent. Number of fish recorded in the 1!)48 season (May 1 to October 31) was 5,716 ; total catch was estimated at not less than 10,000 with 15,000 a more probable figure. Observed ratio of marked to unmarked fish indi- cates that 96 percent of all fish caught came from the March, 1948, plant, making the yield from 48 to 72 percent. The 143,000 fingerlings placed in the reservoir in 1947 yielded practically nothing to the 1948 anglers. This, and the scarcity of naturally spawned fish in 1948, may be ascribed in large part to highly unfavorable conditions both in the reservoir and in its tributaries during the late summer of 1947. Number of trout recorded at the boat landing in 1949 (season Mav 1 to July 15) was 2,373 (Murphy and Pintler, 1950). Total catch was estimated at not less than 4,700, with 7,100 a more probable figure. Analysis of 121 scale samples indicated that approximately two-thirds of these came from the plant of April, 1949, or from 3,130 to 4,730, giving a yield from the 41,400 planted 5- to 6-inch trout of 7.6 to 11.4 percent. YIELD OF HATCHERY TROUT 211 These low figures are due in part at least to the low fishing pressure (and perhaps also to the greater amount of water in the reservoir). Not only was the season shorter than in 1948, but in the same period only half as many boat-anglers fished the lake. Of carry-over of the 1948 plant there was no evidence; not one of the 1,000 fish marked then was seen in 1949 among the more than 600 trout examined by professional workers. Average of all figures for plants of catchable fish — 48 to 72 percent yield for the 1948 catchable fish, 7.6 to 11.4 percent for the 1949 — gives a mean yield for all plants of catchable fish in Conn Valley Reservoir of 35 percent. In the opinion of those who carried on the work, the probability is that the true figure is considerably higher than this esti- mate. Hume Lake, Fresno County, was formed by a dam in 1909 some 70 miles from the City of Fresno. At an elevation of 5,300 feet, it has when full a surface area of 94 acres, a volume of 1,800 acre-feet, and a depth of 45 feet. "Winter conditions include snow and ice for about four months. Spawning has been practically impossible during the period covered by the census. A naturally good trout habitat, although too warm for good fishing in midsummer, Hume twice has been overrun by rough fish, and has had its entire fish population destroyed by chemical treat- ment in 1940 and again in 1947. Since then a basic policy of stocking approximately 30,000 subcatchable (4-J- to 5-inch) rainbow trout each autumn has been followed. None of these fish have been marked, but since natural spawning has been almost nil, the number of fish caught which did not come from the hatchery plants may be assumed to have been negligible. Creel counts made on eight days, all either Sundays or holidays, spaced at fairly regular intervals throughout the 1949 season, the first on May 1 and the last on October 30, form the only basis for an estimate of the total catch. To quote from the unpublished report (Soule, 1950) : ' There is no means by which a reliable estimate as to the total catch can be made from the foregoing facts. It is possible however to compute a total catch figure if certain assumptions are made. The total harvest computation so obtained can be used to advantage if the user clearly understands the fragile and possibly inaccurate framework upon which it rests. The writer has taken into consideration his knowledge of the lake and of the people who fish it as a basis for estimating the season's total catch from the creel census data. At best the result is merely an informed guess and is open to argument on many points. ' ' By the most careful and detailed methods, weighted for Sundays, holidays, week-days, monthly variations, etc., an estimate of 17,000 for the total catch is arrived at ; and it is pointed out that a number of other methods were tried and gave estimates varying from 13,000 to 20,000. Never forgetting that what we have here is "merely an informed guess," it seems worth while using as, at least, a directional signpost. With an annual planting of approximately 30,000 as the denominator, a catch of 17,000 gives a yield of 57 percent for the season of 1949. In view of the nature of the data, it is probably wise to say, for the purposes of this paper, that the yield was "not less than 50 percent." J!l- CALIFORNIA FISH AND GAME Total fishing was estimated at 7,000 angler-days, making an average of nearly 75 per acre for the season. Catch ran as high as 0.75 per hour on May 1, as low as 0.13 on Labor Day — September 5 — with the average estimate at 0.5. Stocking has averaged about 320 fish per acre. Crowley Lake, Mono County, part of the Los Angeles water supply, holds 183,000 acre-feet of water. Its elevation is 6,780 feet, sur- face area 5,284 acres, depth 115 feet. There is some spawning in the tributaries. Plantings of rainbow trout averaged around 110,000 annu- ally for the four years 1946-1949, but variations both in numbers and in sizes from year to year were so great as to make it inadvisable to try to derive yield figures for this species from the periodic creel counts held in 1947 and 1949. However, the situation is different with cutthroat (Salmo clarkii). Between August 24 and September 28, 1946, some 817,000 finger- lings, ranging from 15 to 32 per ounce (L§ to 2 inches long) were intro- duced into the lake. None of these fish could have produced natural offspring big enough to enter the catch prior to 1950, and no more of this species were planted until late 1949. It is therefore certain that all cutthroat in the 1!)47 and 1949 creel counts came from the 1946 finger- lings. Estimates based on these creel counts, with observations and inter- polations for 1948, give the figure of 8,500 as the total harvest through 1949 from 817,000 fingerlings, for a yield of 1.04 percent. Giving all benefit of doubt to the fish which still remain in the lake, the yield from this planting by the time it reaches the end of its life in the fishery could not exceed 1.5 percent. Again we find fingerlings planted in a large lake, where other fish are present, producing a very small yield. COMPOSITE PICTURE OF THE YIELDS We are now in a position to view with understanding the contents of Table 10. All scientific work attempts to avoid the subjective, and yet that element is present in parts of this table. In some cases it is non- extant, In Crystal Lake an objectively counted number of fish were caught from an objectively counted number planted to give a purely objective yield of 71.6 percent, The same thing is true of the Castle Lake work, even though, in the fingerling part of the first phase, the purely arithmetic figure of 3.6 percent has been raised to 4.0 percent; for this has been done by projecting known results obtained from repeated experience in the past into a very near future. But in Frog Lake the observation that 20 percent of the catch went unrecorded, and the adjust- ment of the yield figure from 2.3 to 2.9 percent to compensate for this, is based largely on the opinion of the creel-counter ; it may be presumed to be on the conservative side, but it partakes of the subjective. From here on, this element enters more and more into Table 10. The last column is to some extent an attempt to indicate its importance in each case, but this column is in itself subjective in that it records the opinion of the writer. The yield figures given in the table are sadly inconsistent. One way to deal with them is to average them. There are two objections to this : the varying degree of subjectivity — of reliability — -in the various cases; and the variation in the environmental conditions. If one does insist on an YIELD OK HATCHERY TROUT 213 V) (8 -I re E re O LU 3 -1 O L. CO h < r- V X o *J re I e been t after -cijz: -§§? 82 id low f 1947 shore I* o CD CM > --a 3°^ 00 s a; J3 rt!C6B CD rjj a .2 03 la > CO 5 o o o Qj O CO _ * cu_Q -* +J o >> ■+3 IS .S3 l- i— o QJ CD t- b0 a> a es estimate of fish which would h: illed by chemical treatment in 194 no allowance for fish still to be cau 3 3 u3 l« «*- -O. O co If" o o CM**-" b qj o o — £ 3 fe 1^ =2 o o3 =1 -^ o3 03 is based on mean of 2.7 for high 946 plant and on complete failure icords combined with estimate OS OS o OS _o. £? ™ OS J3 — CO O i- co t ** ^ bD C3.S **3 EQ . CO u o -f3 total harvest lor 4 years. Good. Estimate is based on partial counts. Fair. Yield estimate is mean of high and low estima years, based on boat records and estimate of shore "Informed guess." Excellent. Includ caught if not k Excellent. Makes July 31, 1950. High. Estimate m Fair. Estimate m u, to % . Fair. Y'ield figure estimates for 1 plant. Boat n catch. Low. Based on es polated, and al Excellent. Excellent. Excellent. High. Actual cou 2 § CD CO Ost^ CM -rf * % -TNCO I! -H-H -H *v »C oj es O NN-HQO U0U0 © CM l _ i CM TfH t- -i* CO CO uo <" fci o .-^ et> >H & s§ o 5-- (O .2 i £ O CO -3 ^_ 03 -O i 03 "^3 cfl =3 33 = o 33 rt-13 — ^2 — ^3 O i T3 co O w < < <-c < O CO <<<< '£ ! °o a o *"8 (S ^H CO CD > (=H ! "a3 ^ o3 a . a? Q a) S 9i ^fc^a ST 3 o3 u. a> H ci 0> •« °S > § |fc S3 lO W3 © »o co^- m •o CM UO © © © OO © CM CM »d OS -c CM UO CO CM OO UO »C CO CM T3 -r -r T CS Q. 7-1 -^ OS CM co" i-H CO C3 cap, o CO J= co co H5 cccQ H H Eh wjQhh P3H H £ cd '3 a CQ W w « Pi O Htftf Wtf Pi a o o iC "^ o CD ifl © © oo© «^0 uo .— +j CM CM -ti to CM tNOI'-t CO -h -tn J3 a. ^-1 r-. *—t l"H »— i T-H l— ( 1—1 "- 1 -£?*£ & - a> — Q'~ r- t>- ccoo O o tH i-- r- © © 00 © ^ -p -r CO so o o oo -ji -^ ^_, ^« CO© OS li 03 co" CO uo" CO oo 3 — CM m.S a o o ©© CD ■o © ©©©© ©uo © o +^ o o © © o oo ©©©© ©ft © ^ *o lO t~»« t-^- -p ee lO >0 >C N t^ u^ » V a cu 1 I CD B OS S5 8- N S"3 i 3 a o o +3 ^"^ «J op ==1 a 3 O 3 o fc-O (i individuals, requires creation of a refuge on the largest breeding ground; and that the Cuban subspecies, which is estimated at less than 50 breeding pairs, is vitally in need of protection. The greater sandhill population is esti- mated at betwen 2,600 and 8,700 and is felt to be in a more stable condition than either the Florida or the Cuban. The lesser is by far the most abundant and, while the author makes no estimate of numbers, he states that flocks of up to 100,000 are still reported. This subspecies breeds in the far north and is in much better circumstances than are the others. The chief criticism of this work is its mass of confusing and unnecessary detail. In many spots field notes appear to have been transcribed practically verbatim. The reader is not given the benefit of the summarizations and condensations which only the author can make. Though the book falls short of being a well-rounded life history treatise it is nevertheless valuable as a monograph of a little-known species. — Fred L. Jones, Cali- fornia Division of Fish and Game. Conservation of Our Natural Resources Edited by Guy-Harold Smith. John Wiley and Sons, Inc., New York and London, 1950 ; xii + 552 p. $6.00. Conservation has been the theme of many hooks, books reflecting all degrees of quality and of opinion. This one grew from "Our Natural Resources and Their Conser- vation," first, published in 1936 and revised in 1939. While it would be too much to expect everyone to agree with each of the 20 contributors, the book is, by and large, very good. Though designed primarily as a college-level text, it deserves a much wider audience, for, as Dr. Smith says in the preface. "The adult reader, whether well informed about conservation or not, will find here the essentials of the conservation movement which needs new enthusiasts and readers." It is doubtful that anyone could fail to benefit from the story for even in the vari- ous fields of conservation itself there is a tendency for some workers to think of their particular phase without considering its relation to the whole. They seem to remain unaware of what the word "conservation" in its broad sense means. It is, then, not sur- prising that among the multitude of people to whom one of these phases is a hobby or a source of recreation there are many who are even more unaware. Controversy based more on emotion than reason may rise between proponents of two or more conservation groups, each sincerely devoted to its own cause and each failing to recognize that the ends all desire are reconcilable parts of a single picture. It follows that there is a great deal of misunderstanding and ignorance which must be overcome before the general public whose concern it is realizes what the word implies in terms of everyone's life. This books presents the views of competent men concerned with conservation of soil, agriculture, forests, water, minerals, wildlife and fisheries, and with the conservation of man himself. Through the stimulation of thought as well as through education it should make a lasting impression on its readers. — Phil M. JRoedel, California Division of Fish and Game. Fishing in Many Waters By James Hornell ; Cambridge University Press, London and New York, 1950 ; xv + 210 p., 44 text figures, 36 plates. $6. This book is the epitaph of a man who spent a lifetime studying fisheries for the British government in many parts of the world. It is too bad that he did not live to see it in its final printed form. The story is of fishing methods as practiced by a multitude of peoples from the most primitive to the most modern, with emphasis on the primitive, the unusual and the ob- scure. Most of the book deals with the Far East, especially India, and the south Pacific, and most of it is based on first-hand experience. The descriptions are detailed but never dull ; the topics are diverse as these selected chapter titles show : "Weapons of the Chase Borrowed by the Fisherman," "Collecting and Curing the Bombay-duck," "Baiting for Crocodiles and Alligators," "The Grey Mullet Takes Evasive Action." There is a bibliog- raphy and an index. Bits of folk-lore and tales of peoples' customs serve as added spice to the accounts of fishing, and bear out the dust jacket claim that "... anthropologists will find it a valuable contribution to the study of material culture." The book is very well-written and is excellently illustrated with line drawings and photographs. I recommend it to the general reader and the student of fisheries alike. — Phil M. Roedel, California Division of Fish and Game. REPORTS FISH CASES October, November, December, 1950 Offense Number arrests Fines imposed Jail sentences (days) Abalone: Overlimit; undersize; failure to show license; using for bait. . 31 201 1 2 82 2 12 14 1 80 103 7 21 14 38 2 15 $910 00 2,590 00 50 00 30 00 3,130 00 35 00 355 00 390 00 15 00 2,348 00 4,230 00 300 00 464 50 950 00 935 00 50 00 362 00 900 00 609 06 Angling: No license; using another's license; failure to show license; transferring license to another; no out-of-state license; nonresident using resident license; making false statement to obtain license; 2 lines; 2 poles; fishing in closed waters; possession of angling gear in fish refuge; night fishing; possession of gaff on stream; possession of spear within 300 feet of river; attempting to spear on spawning bed ... _ _. 90 Barracuda: Overlimit on sport boat . _ .. Bass, Black: Overlimit Bass, Striped: Failure to show fish; overlimit; undersize; more than one line; 2 poles; using undersize for bait; failure to show license; taking other than by angling; hiding undersize fish; possession for sale; taking in nets; taking at night 10 Bluegill: Overlimit; no license _ Catfish: Undersize; taking at night; 2 poles; set lines.. _._ _. . Clam, Cockle: Overlimit; undersize; no license... Clam, Horseneck: Overlimit Clam, Pismo: Undersize; overlimit; taking in State clam preserve; taking at night; no license; after hours Commercial: Dragnet, closed season; no commercial license; no boat registra- tion; failure to make out forms correctly; taking overlimit on commercial boat; round haul net in closed area; operating purse seine in District 118.5; illegal possession of fish in District 118.5; failure to keep trawl log; failure to keep records and issue tickets; no dealer's license; no receipt issued Crab: Closed season and undersize; possession and sale, undersize... Lobster: Undersize; closed season; no commercial license; snagging. . ._ 5 2J 2 Pollution: Oil; fish refuse Salmon: Taking after hours, before hours, in closed area, in spawning beds, with 2 poles, with hands, by snagging; no license; gaffing; possession of spears on spawning beds ; shooting in spawning area 150 Shad: Closed season Trout: Taking from closed stream; selling untagged commercial trout; failure to declare; overlimit; transporting untagged; transporting illegal trout in California; steelhead, closed season; 2 poles; spear; unattended rod Seizures: Sardines Mackerel Totals 626 $18,653 56 257J-4 (227) 228 CALIFORNIA FISH AND GAME GAME CASES October, November, December, 1950 Offense Number arrests Fines imposed Jail sentences (days) Antelope: Illegal possession Coot: Shooting and not retrieving; late shooting; taking from moving vehicle (powerboat); closed season; taking with .22 rifle Crane: Taking full protected bird Deer: Closed season; overlimit; overlimit doe; taking doe, spike buck, fawn, doe without permit, forked horn in District 154. 2 deer in one-deer district; taking after sunset; spotlighting; night hunting; failure to show license; no deer tags; transfer of tags; failure to return tag, to fill out tag; using No. 2 tag in No. 1 district; no nonresident license; discharging gun and taking deer in game refuge; taking with full metal-jacketed bullets; shooting from car; using rim-fire rifle Deer Meat: Possession in closed season; failure to mark shipped meat; possession of parts of illegal deer; possession of unstamped meat in closed season; trans- porting illegal meat into California Dove: Transfer of license and shipping tags; overlimit; shooting from a vehicle; unplugged gun; using another's license; overlimit brought from Mexico; after hours; no license; closed season; late shooting Duck: No license; overlimit; late shooting; unplugged gun; shooting from a powerboat; early shooting; closed season; hunting in refuge; failure to show license; hunting in closed area; unsigned stamp; attempting to take from auto with rifle; taking with pistol Elk: Killing full protected animal Killing two elk Goose: Early shooting; overlimit; improperly plugged gun; offering overlimit for shipment; hunting without license; receiving and accepting overlimit for shipment; late shooting; hunting on refuge; driving with powerboat; closed Hunting: Shooting in closed area; hunting in restricted zone; hunting on coop- erative area; using unplugged shotgun; hunting from powerboat, from auto; late shooting; early shooting; destroying state and federal hunting signs; pos- sessing and displaying another's license; no license; possession of gun on refuge; trespassing on cooperative area; no license; night hunting; spotlighting; making false statement to obtain resident license and deer tags; transferring license; transferring shipping tags; failure to fill out tag; using full metal- jacketed bullets; failure to show license on demand Muskrat: Trapping in closed season and having no trapper's license Nongame Birds: Taking meadow larks, barred owl, seagull, grebes; taking from motorboat Pheasant: Having no tags; taking in restricted area; shooting from public road; early shooting; failure to tag; overlimit; taking hen; closed season; shooting from car; trespassing on closed zone; hunting with .22 rifle; failure to tag on Game Management Area; hunting pheasant with unplugged gun; possession in closed season; no license; possession of another's tags; possession of two sets of tags other than those legally issued Pigeon: Taking bandtail in closed season Quail: Bringing into state quail taken in Mexico during closed season; closed season; unplugged gun; early shooting Rabbit: No license; closed season; night hunting; unplugged gun; spotlighting; failure to show license; taking cottontails in closed season; taking in refuge; early shooting, jackrabbit Shore Birds: Taking plover, rail, killdeer, jacksnipe Squirrel: Taking tree squirrels, closed season; possession in closed season Totals. 11 1 115 27 75 187 1 16 319 1 10 183 3 21 60 6 1 1,103 1100 00 280 00 25 00 11,793 00 3,178 00 2,380 00 6,282 00 (1250 00 suspended) 500 00 118 00 11,233 50 10 00 365 00 1,945 00 200 00 715 00 1,225 00 195 00 125 00 $51,299 50 199 11 87 H 65 112 REPORTS 229 SEIZURES OF FISH AND GAME October, November, December, 1950 Fish: Abalone 493 Barracuda . - 44 Bass, Black 1.. _.. 13 Bass, Striped ("554 pounds) 354 Bluegill 38 Catfish (43 pounds) 53 Clam, Cockle.... 3,371 Clam, Pismo 1,226 Clam, Horseneck 44 Crab 184 Lobster 240 Rockfish.... 20 Salmon (800 pounds) 43 Sardines, pounds 291,000 Shad 3 Trout 120 Game: Coot 25 Crane I Deer 113' 2 Deer Meat (pounds) 398 Dove 838 Duck 358 Elk 4 Goose 37 Muskrat 5 Nongame Birds 19 Pheasant 144 Pigeon 14 Quail 27 Rabbit 18 Shore Birds _. 11 Squirrel 7 printed in California state printing office 39247 12-50 7,500