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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 FISHES1
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 tin1 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. 33c 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 GURDIES1
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 NEVADA1
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,
CALIFORNIA1
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'{'&lj'-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 <jiant melanophores was present on the nape. The eye and lens were solid black. The pectoral fins were very small and the rays only slightly developed. The anus was far posterior in position.
The only larva that hatched died approximately 12 hours after it emerged. So far as could be seen, it had no special structures on the head for breaking the egg membrane.
REFERENCE Fry, Donald H., Jr.
1936. Life history of Hesperoleucus ven ii st us Snyder. California Fish and Game, vol. 22, no.' 2, p. 65-98, 8 figs.
THE M.V. YELLOWFIN,
AN ADDITION TO CALIFORNIA'S MARINE
FISHERIES INVESTIGATIONS'
By Robert ('. Wilson
Bureau of Marine Fisheries
California Division of Fish and Game
INTRODUCTION
The close of World War 1 1 saw a resumption of full-scale investiga- tion of our marine resources by the California Division of Fish and Game. This made more evident the need for additional research facilities at sea to augment and speed up the collection of data about pelagic fish and the environment in which these species live. To meet this need plans were made to acquire a second research vessel to supplement the work of the N. B. Scofield, in service since 1938. Before a second vessel could be obtained the failure of the sardine fishery in 1946-47 brought home to the industry the necessity for increased research, to find the reasons for such a failure. The backing of the industry served as a further stimulus to establish the need for additional research vessels of a size sufficient to carry out a high seas investigation.
Funds were made available by the Legislature to the Division of Fish and Game for the purchase and conversion of one additional research vessel, and the F. S. 64 was purchased May, 1948, and renamed Yellow- fin for conversion into a marine research vessel.
The F. S. 64 was constructed for the U. S. Army in 1943, at Stoning- ton, Maine, from a design prepared by H. C. Hanson, Naval Architect. She was planned for interisland freight and passenger service. The vessel subsequently saw service in Pacific waters until the close of the war, when she was laid up and declared surplus.
DESCRIPTION
Basic construction of the vessel is wood, with four transverse bulk- heads of steel. All tanks are of steel.
Construction is to the following specifications :
Length over-all 113 feet, 85 inches
Length between perpendiculars 107 feet. 3 inches
Molded beam 20 feet (1 inches
Beam over planking 27 feet 0 inches
1 >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; 0 crystal controlled channels. Receiver side: 0 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
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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, 1946-19491
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 |
0 0 0 80 603 455 |
3,720 4,155 4.155 3,560 3,966 4,225 |
40 230 230 800 509 430 |
0 0 0 0 0 130 |
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 foi4 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 cars1 |
Average number hunters/car2 |
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 |
0 39 |
|
1948 |
0 55 |
||||
|
1949 ._ |
0 60 |
||||
|
McManus 1947 |
0.40 |
||||
|
1948 |
0.63 |
||||
|
1949 |
0 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
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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
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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
<r o <
o o o
a. o
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in
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CD
220 -
200
180
160
140
TOTAL BIRDS KILLED PER 1000 ACRES
1947 - 147.8
1948 - 466 8
1949 " 245.2
DAY OF SEASON
Figure 73. Kill per 1,000 acres per day on the Sartain Ranch
PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY
151
releases of game farm birds on Sartain's would have tended to reduce hunting pressure on the wild stock there.
Birds Killed Per 1,000 Acres
Figures 73 and 74 show the number of birds killed per 1,000 acres each day of the season on the Sartain and McManus areas from 1947 to 1949. On the Sartain area the total kill, which included both wild and
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140
120
100
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TOTAL BIRDS KILLED PER 1000 ACRES
1947- 122.8 1948-340.5 949- 182.0
Figure
DAY OF SEASON Kill per 1,000 acres per day on the McManus area
game farm birds, was 147.8 per 1.000 acres in 1947, 466.8 in 1948, and 245.2 in 1949. On the McManus area, where no game farm birds were planted, the kill was 122.8 per 1,000 acres in 1947, 340.5 in 1948, and 182.0 in 1949. The kill per 1,000 acres on the Sartain area has exceeded that on the McManus for every year, but the hunting pressure, with the exception of 1949, has also been greater. Also, the kill of stocked birds on Sartain's increased the take per 1,000 acres. Total resident wild bird kill on Sartain's in 1949 was 1,073 ; this would give a bag of 155.5 birds per 1,000 acres which is 26.5 less than for the McManus.
The rise in kill on the last day of the season on Sartain 's in 1948 and 1949 was due to shooting in the restricted zone (Figure 73). Hunting on the 1,280 acres in this zone was negligible until the last day of the season and consequently it acted as a refuge until that time.
152
CALIFORNIA FISH AND GAME
Kill by Day
Dajr by clay take on both areas followed the same general trend each \ car. On Sartain's the percentage of total kill by days is shown in Fig- ure 75; the same data for the MeManus area are given in Figure 76. The percentage of kill for the first three days, the five week days, and the last two days of the 1947-1949 seasons for both areas is shown in these figures. The rise in the daily percentage of the total kill on the fifth and sixth days of the 1949 season on Sartain's was due to the planting of 193 game farm cocks on the evening of the fourth day. These birds made up 65.0 percent of the total bag on the fifth day and 17.9 percent of the hag on the sixth day of the season (Figure 80) . This also had the effect of ilccreasing the percentage of the total kill made on the first day and first three days of the season by increasing the percentage of kill made during midseason.
The increased percentage of the total kill occurring in the early part of the season on the McManus area in 1949 can be explained on the basis of hunting pressure. In 1949, 84.0 percent of the season's gun hours was expended in the first three days, whereas 72.0 percent of the hunting was done in this same period in 1948 (Figure 72) . This increased hunting
60
50
40 -
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20
10
0
60
I
SUMMARIZATION (PERCENT)
|
1ST |
3 |
5WEEK |
LAST 2 |
|
|
DAYS |
DAYS |
DAYS |
||
|
1947 |
79 |
12 |
9 |
|
|
1948 |
81 |
II |
8 |
|
|
1949 |
73 |
18 |
9 |
/
■y
1949 1948 1947
50
40
30
20
8
10
DAY OF SEASON Figure 75. Daily percentage of birds killed on the Sartain Ranch
50
40
30
UJ
o
cr
20
10
0
PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY
SUMMARIZATION (PERCENT)
1ST 3 5 WEEK LAST 2 DAYS DAYS DAYS
1947 79 II 10
1948 77 14 9
1949 87 9 4
1947 1948 1949
8
10
24 22
20
|
Q |
18 |
|
ir |
|
|
m |
|
|
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|
|
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z |
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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
0
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
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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
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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
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100
80
60
40
20
. GAME FARM BIRDS , PRE- SEASON RELEASE
-7777
100
80
60
40
20
DAY OF SEASON
1949
Figure 79. Daily composition of kill on the Sartain Ranch
PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY
157
of the total bag. The bag from 799 game farm birds released in 1948 made up 8.7 percent of the seasonal kill. However, 36.8 percent of the kill in 1949 was from 1,515 birds stocked during the year. Of this, the kill from the 1,041 game farm birds was 22.5 percent of the total seasonal kill and the kill from 474 transplanted wild birds was 14.3 percent. Thus it can be seen that the bag of game farm birds in relation to numbers released was of little importance in the total kill in 1948, but in 1947 and 1949 the kill of stocked birds was more significant. The percentage of stocked birds in the bag is a reflection of the population level of wild birds for the year.
z
UJ
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UJ 0.
|
I |
|||
|
50 |
, \ |
. |
|
|
\ \ |
RESIDENT WILD BIRDS |
2,949 |
|
|
40 |
\ \ |
GAME FARM BIRDS |
- |
|
\\ |
( PRE-SEASON RELEASE) |
281 |
|
|
30 |
V |
TOTAL BAG |
3,2 30 |
|
20 |
- |
||
|
10 |
• ■ |
■ |
|
|
n |
3 4 5 6 7
DAY OF SEASON 1948
8
50 40 30 20
10 0
10
UJ
o
cr
UJ CO-
RESIDENT WILD BIRDS 1,073
GAME FARM BIRDS (PRE-SEASON RELEASE) 248
GAME FARM BIRDS (IN-SEASON RELEASE) 134
TRANSPLANTED WILD BIRDS
TOTAL BAG 1,697
70
60
50
40
30
20
10
0 5 6 7 8 9 10
DAY OF SEASON
1949
Figure 80. Daily percentage of total seasonal wild bird and game farm bird kill on the Sartain Ranch. "* Resident wild birds" includes game farm birds from previous years ;
1948 — 3, 1949—9.
i:>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
0
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 ratio1 |
.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 ratio1 |
.10 |
|||||
|
Checked kill of cocks |
1,420 |
|||||
|
Crippling loss of cocks2 |
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 |
0 14 28 35 |
0 |
|
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
<r
UJ Q.
1949
1948
8
10
12
14
Figure 86.
BY AGE IN WEEKS AT TIME OF RELEASE Known mortality of game farm birds soon after release on Sartain Ranch
on different dates and at various ages. August releases of both 1948 and 1949 appear to be subjected to greater mortality than those of any other single release. This is further reflected in fewer hunting season returns from these releases (Figure 87).
There appears to be a relation between ages of birds at release and subsequent mortality. In general, more birds of younger age classes were found dead than of older classes, perhaps because older birds disperse more readily. Younger birds (6 to 10 weeks old) were found flocked even after several weeks in the field. This increased the possibility of a single predator killing a large number. Releasing birds in small groups throughout the area to be stocked may reduce the possibility of large number of birds being killed while they are concentrated near releasing points.
168
( \UFORNIA FISH AND GAME
90
80
70
60
50
CE
3 I- UJ
cr 40
o
or
lu 30
Q_
20
1949 \
-i u
_i I i u
j i 1 1 1 1_
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 I/O
DAYS IN FIELD
Figure 87. Comparison of returns from preseason releases of game farm cocks
on the Sartain area
Feral house cats are by far the. greatest cause of mortality of game farm birds in the Sacramento Valley. Many of the birds listed as dead from unknown causes apparently were unable to make the transition from game farm conditions to surviving in the wild and died of shock or other unrecognizable causes. Table 16 presents known mortality data.
TABLE 16
Mortality Factors of Game Farm Birds on Sartain's
1948-1949
|
House cat |
Automobile |
Unknown |
|
|
1948 |
2 68 |
3 7 |
15 |
|
1949 . |
34 |
||
|
Totals |
70 54.3 |
10 7.7 |
49 |
|
Percent . |
38.0 |
||
PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY 169
Hunting Season Returns
Of the 848 game farm cocks released before the season in 1949, bands from 31.9 percent were returned. This compares closely with the 35.0 percent return from 799 cocks planted in 1949 and the 32.7 percent return from 300 males stocked in 1947. The 1947 plant consisted of 14-week-old cocks liberated September 10-12. In 1946, 220 cocks, 18 weeks old, released in mid-October produced a 37.7 percent return.
The return of game farm cocks in 1949 was comparable to the 1948 return for similar age classes and days in the field before the season. When two or more age classes were released at the same time, older birds gave greater returns, as shown in Table 15. The single exception to this occurred in returns from 8- and 10-week birds released in August, 1949, when a greater percentage of eight-week birds was returned.
Returns from birds in the field longer than 66 days before the season were variable and, with one exception, less than 40 percent. Cocks in the field 66 days or less yielded returns tending to be inversely proportional to the length of time in the field. Greatest returns were approximately 81 and 84 percent from birds released two days before the season. Cocks liberated 65-66 days before the season yielded returns of 43-46 percent, while those in the field approximately half that time gave returns of 55-56 percent, which is only 10-12 percent greater. An inseason release of 193 game farm cocks (age 20 weeks) in 1949 gave a return of 69.4 per- cent. These figures show that releases should be made during a short period of time before the season opens if maximum returns are the primary objective.
In 1949, lower returns from the inseason release than from the release made two days before the season demonstrates that hunting pressure, in addition to survival, is an important factor in the kill return of game farm birds. The inseason release was subjected to a minimum hunting pressure of 379 gun hours per 1,000 acres (last five days of season) to yield a return of 69.4 percent. The immediate preseason re- lease had a pressure of 1,722 gun hours per 1,000 acres (all 10 days) and gave a return of 83.8 percent, which is 14.4 percent greater. In contrast to this, returns from game farm birds in the field 66 days or less in 1948, when hunting pressure (10 days) was 2,949 gun hours per 1,000 acres, corresponded closely with returns in 1949. Assuming that survival of these birds was approximately the same for both years, the lower but still intensive seasonal hunting pressure exerted in 1949 was sufficient to harvest maximum returns.
The relationship of hunting pressure to returns of game farm birds is not clearly understood, but the data indicate intensive hunting pres- sure as well as liberating birds a short time before the hunting season is necessary to harvest maximum returns of game farm birds.
Survival of game farm birds from releases made in June and July was evidently greater than that of birds liberated in the first half of August, even though their period of time in the field before the season was a month or more longer (Figure 87). Releases of six- week birds in early August were the only ones which resulted in no returns during 1948 and 1949. This indicates that conditions in early August were generally unfavorable for the liberation of pheasants on the Sartain area and pos- sibly throughout the general rice growing section.
170 CALIFORNIA FISH AND GAME
Returns of game farm cocks in the field longer than one year were very low. In 1949 a total of nine birds, representing a 1.1 percent return, was killed from game farm releases made in 1948 on the Sartain ranch. A total of three, or 1.0 percent return, was killed in 1948 from birds liberated before the previous (1947) hunting season. These birds made up a minute percentage of the total kill on the area, and it is evident tli at returns from game farm cocks on a beavily hunted area are insignificant after the first hunting season following their release.
Game farm birds in the field a month or more before the hunting season evidently are not killed any more readily than are wild birds on a heavily hunted area. In 1948 the daily percentage of the total seasonal wild bird kill and kill of all game farm birds was remarkably constant throughout the season, as shown in Figure 80. In 1949 the percentage of the total seasonal kill made on the first day of the season was nearly 30 percent greater for game farm birds than for wild birds. This increase was due to very heavy hunting pressure in the preseason release area, as discussed before. The percentage of the total seasonal kill of game farm birds made on the first day of the 1949 season was greatly increased by the take of game farm stock released two days before the season. For this group of birds, 84.4 percent of the total kill was made on the first day, and 96.4 percent in the first three days of the season. The kill of inseason-released game farm birds occurring on the first day after release was 64.7 percent of their total kill, and 95.5 percent was taken by the end of the third day. It is evident that game farm birds released in season or a few clays before the season are harvested more readily by hunters than are other birds.
Information gained in the course of the study shows that failure to recognize game farm or other banded birds in the bag because of loss of bands was not an important factor. Birds less than nine weeks of age were wing banded, and in 1949 all cocks nine weeks of age or older were both wing and leg banded. The use of both types of bands provided a check on loss of each. During the 1949 hunting season on the Sartain area, a total of 563 birds was checked that were known to have been both wing and leg banded. Of this group, four leg bands and 11 wing bands were miss- ing. This is a loss of less than 1 percent for leg bands and approximately 2 percent for wing bands ; loss of both bands from a bird would be very rare. Loss of wing bands is in part due to faulty technique of the bander in clipping the wing band through the patagium.
Game farm birds showed little tendency to move off the area. Returns from 405 cocks released in 1949 revealed that 98.3 percent were taken on the study area or along its borders within a radius of two miles from the point of release. One game farm bird released four months before the season was reported killed 14 miles away. All other returns were within a five-mile radius of the release site.
SURVIVAL AND RETURN OF WILD BIRDS
Considerable information on the survival and bag of wild banded pheasants was obtained during the 1949 hunting season on the Sartain area. A total of 763 wild cocks of various age classes was banded and released on Sartain 's between July and October. Of these, 474 were transplanted cocks i*emoved from state and federal waterfowl refuges,
PHEASANT POPULATIONS IN THE SACRAMENTO VALLEY
171
and 289 were resident males caught on the Sartain ranch. Age classes of these birds, days in the field before season, and returns are shown in Table 17 for resident birds and Table 18 for transplanted birds. Juvenile
TABLE 17 Returns From Resident Wild Banded Cocks on the Sartain Area, 1949
|
Age banded (weeks) |
Number banded |
Date of release |
Average number of days in field (before season) |
Percent return |
|
5 |
8) 15| 38 27 14. |
July 27-31 |
113 |
62.5 |
|
6- 8... |
6.7 |
|||
|
8-10 10-12 Adult |
is. 1 29.6 64.3 |
|||
|
5 6- 8... |
31 8 29 96 12 39. |
Aug. 11-28 |
90 |
0.0 25.0 |
|
8-10 10-12 12-14 Adult |
27.6 29.2 33.3 51.3 |
|||
|
Total juveniles. . - . Total adults . |
236 53 |
26.7 |
||
|
54.7 |
||||
|
289 |
31.8 |
|||
TABLE 18 Returns From Transplanted Wild Banded Cocks on the Sartain Area, 1949
|
Age banded (weeks) |
Number banded |
Date of release |
Average number of days in field (before season) |
Percent return |
|
6- 8 |
151 28 39 21J |
July 27-31 |
113 |
20.0 |
|
8-10 |
42.9 |
|||
|
10-12,.. |
48.7- |
|||
|
Adult |
47.6 |
|||
|
6- 8 |
1 5 40- 14 36 |
Aug. 11-28 |
90. |
1(10.0 |
|
8-10 |
40.0 |
|||
|
10-12 |
45.0 |
|||
|
12-14 |
42.9 |
|||
|
Adult |
61.1 |
|||
|
8-10 |
2) 20 39 54j |
Sept. 7-8 |
72 |
50.0 |
|
10-12 |
35.0 |
|||
|
12-14 |
48.7 |
|||
|
Adult.. |
63.0 |
|||
|
6- 8 |
1) 2 8- 28 56. |
Sept. 22-29 |
55 |
0.0 |
|
8-10 |
0.0 |
|||
|
10-12 |
50.0 |
|||
|
12-14.. |
67.9 |
|||
|
Adult... |
62.5 |
|||
|
14-16 |
211 44/ |
Oct. 5-11 |
„{ |
42.9 |
|
Adult |
70.5 |
|||
|
263 211 |
45.6 |
|||
|
Total adults |
62.6 |
|||
|
Grand totals |
474 |
53.2 |
||
wild birds were aged by the moult pattern of the primary wing feathers ; bursa probing was necessary to segregate a few juveniles from adults in late September and October.
The hunting season return of 31.8 percent for banded resident birds appears low when compared to returns from other classes of banded
172
CALIFORNIA FISH AND GAME
birds. Most of these were caught and banded in the restricted zone of the Sartain Cooperative Hunting Area incidental to the process of develop- ing techniques and equipment for catching pheasants in California at night with the use of spotlights. Hunting pressure was comparatively light on the restricted area and consequently a low return of birds in this area would be expected.
Total returns from transplanted wild birds were 53.2 percent, with juveniles yielding a 45.6 percent return compared to 62.6 percent from adults.
TABLE 19
Comparison of Band Returns From Transplanted Wild Birds and Game Farm Birds on the Sartain Area, 1949
|
Type of bird |
Age released (weeks) |
Number released |
Date released |
Average days in field before season |
Percent return |
|
Wild |
6-10 6&8 |
Comparable 43 100 |
Age Groups July 27-31 July 15 |
113... |
34.9 |
|
125... |
12.0 |
||||
|
Wild |
S l_> 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 0 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 VALLEY1
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
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JAN FEB MAR APR MAY JUN JUL AUG SEP OCT N0V„„Df9,
ioor
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REPTILES
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INSECTS
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Figure 90. Seasonal consumption of main classes of food by Sacramento
Valley house cats
182
CALIFORNIA FISH AND GAME
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FOOD HABITS OF FERAL HOUSE CATS
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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 wTas 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. Howrever, 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 wTas 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 w7as 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 ZnSG4 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 measure1 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 ZnS04) 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 ZnS04.
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 0 0 |
10 0 0 0 |
10 |
||
|
6 : |
0 |
||||
|
10 |
0 |
||||
|
14 |
0 |
||||
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 0 |
5 |
|
6 |
2 |
||
|
10 |
0 |
||
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 0 |
20 |
|
3 |
11 |
||
|
4 |
2 |
||
|
6 |
0 |
||
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 MARMORATUS1
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 wTeak 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 wras 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 LAKES1
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. WTales.
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 spring1 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 wrere 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 wrhich 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
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214 CALIFORNIA PISH AND GAME
average, one obtains 5.4 percent for the fmgerlings, and 44.9 for the catch- able fish. These are not unreasonable-looking figures, but to me they are unsatisfactory. They are objective combinations of figures of varying degrees of subjectivity. To me it seems better, since subjectivity is an unavoidable element here, to use it, aided by the best of our intelligence and our experience, in interpreting the results.
Considering fmgerlings first, available evidence from all over the country tells us that their yield when planted in large lakes, especially -where other fish are present, is low. The first step, then, in obtaining a clear understanding of the results to be expected from fmgerlings in small lakes — under 100 acres — is to forget Almanor, Conn Valley, and Crowley, where yields average 1 percent, and to consider only the first four items in Table 10. Average of the yields in these is 8.7 percent. This is obviously distorted by the unusually high figure of 25.3 for Castle Lake second phase. Setting this aside as due to especially favorable conditions, we have the 4.0 percent of Castle Lake first phase based on six years of what might be called normal conditions except for the simultaneous stocking of three species ; the 2.9 percent of Frog Lake under the same kind of conditions with the exception that the unsuitability of rainbow there probably lowered the figure ; and the 2.7 percent of Gull Lake which made no allowance for the fish still remaining in the lake when creel counts had to be terminated, and which would undoubtedly have been higher if they could have been continued another year. The figure of 4 percent stands in the mind of the writer as the yield to be expected over the long run in normal conditions.
When we come to catchable fish, the distribution of figures does not cover so wide a range. The low yield in Castle Lake first phase might be attributed to low stocking and fishing intensity ; in Conn Valley to low stocking and unsuitable environment; in Gull to overstocking of an impoverished environment. The high yield in Crystal is certainly clue to the continuous pouring all season long of catchable fish into a small, extremely heavily fished lake — an uneconomic procedure unless special fees are charged. There remain June. Castle Lake second phase, and Hume. The results here are so closely grouped that they cannot help bringing to mind the figure of 50 percent as the yield to be expected in the long run from the planting of catchable fish.
From the arithmetic averages of 5.4 percent and 44.9 percent, the subjective figures of 4 percent yield from fingerling plants and 50 percent from catchable fish plants do not differ greatly. The reader is at liberty to accept either ; but, most important, he is at liberty to reject both and, with the figures and the qualifying circumstances set forth here, to deter- mine for himself his own idea of the most probable values for the respec- tive yields.
SUMMARY
1. This paper brings together information obtained over 10 years from hatchery trout yield experiments on nine California lakes, of which six are considered of primary and three of secondary importance. Most of these lakes have no or insufficient natural spawning. It is empha- sized that lakes produce very different results from streams.
YIELD OF HATCHERY TROUT 215
2. Figures are given for the yield in each lake : number of fish caught as a percentage of the number planted. Stocking intensity and fishing pressure are also given.
3. The results of the different projects vary widely. From fingerling plants, three large lakes (800 acres and up) produced low yields in comparison with three small lakes (33 to 68 acres). Average yield from the former was 1 percent with a range of 0.2 to 1.5 ; from the lat- ter 8.7 percent with a range of 2.7 to 25.3. In all combined, fingerling plants averaged a yield of 5.4 percent.
4. Extraordinary improvement in yield from fingerling plants occurred in one 47-acre lake when a population of three planted trout species plus resident lake trout (mackinaw) was eliminated and replaced by one species.
5. Plants of catchable trout in seven lake experiments in which areas ranged from 10 to 800 acres gave an average yield of 44.9 percent with a range of 27.4 to 71.6.
6. It is suggested that the arithmetic average yields of 5.4 percent from fingerlings and 44.!) percent from catchable trout take too little account of the variations in the reliability of the figures from which they are formed, and of the nonquantitative factors involved. Knowl- edge and consideration of these lead to the proposal that the figures which best interpret the results obtained in these experiments are: yield from fingerling plants (in lakes under 80 acres), 4 percent; yield from plants of catchable fish, 50 percent.
REFERENCES
Murphy, Garth I., and Herbert E. Pintler
1950. The 1949 fishery of Conn Valley Reservoir, Napa County. Administrative report to the Bureau of Fish Conservation, Calif. Div. Fish and Game, 9 p., submitted July 12, 1950 (mimeographed ) . Smile, Scott M.
1950. Occasional creel censuses at Hume Lake, Fresno County, during 1949. Administrative report to the Bureau of Fisb Conservation, Calif. Div. Fish and Game, 31 p., submitted April 7, 1950 (mimeographed). Vestal, Elden H.
1942. Rough fish control in Gull Lake, Mono County, California. Calif. Fish and Game, vol. 28, no. 1, p. 34-61.
1943. Creel returns from hatchery trout in June Lake. California. Calif. Fish and Game, vol. 29, no. 2, p. 51-63.
^Wales, J. H.
1946. Castle Lake trout investigation. First phase : Interrelationships of four spe- cies. Calif. Fish and Game, vol. 32, no. 3, p. 109-143.
1947. Castle Lake trout investigation : 1946 catch, and chemical removal of all fish. Calif. Fish and Game, vol. 33, no. 4, p. 267-286.
NOTES
A NOTICEABLE ABSENCE OF BLADDER WORMS IN CATALINA DEER
The intermediate stages, or cystleerci, of various tapeworms are commonly known as bladder worms. These white cysts occur most fre- quently on the mesenteries, but are encountered in the liver, thereby causing the disease Hepatitis cysticercosa. The usual species found in California deer is Cysticercus tenuicollis. One case of Echino coccus granulosus was observed at the laboratory.
Several hundred deer from practically every part of the State have been examined by the staff of the Disease Research Laboratory. More than 90 percent of the deer observed at post mortem contained one or more cysts.
During the past special hunting season on Santa Catalina Island opportunity was afforded the author to examine or observe the viscera of 93 deer. Not one of these deer had any observable cysts present. The lack of cysts was immediately apparent as compared with all of the deer previously autopsied on the mainland of California.
The original stock of 22 mule deer were planted on the island some 20 years ago. One buck and two does probably from Modoc County and 19 deer from Los Angeles County comprised the introduced herd. With the introduction of the deer, the bladder worms were undoubtedly also introduced.
The final host for the tapeworm is a carnivore, usually the coyote. A reasonable explanation for the disappearance of the tapeworm cysts on Santa Catalina Island could be the absence of the coyote, thereby breaking the chain of the life cycle. — Merton N. Bosen, Bureau of Game Conservation, California Division of Fish and Came, August, 1950.
COMPOSITION OF DEER MILK
On June 10, 1949, a female black-tail deer (Odocoileus hemionus columbianus) was brought into the California Division of Fish and Game disease laboratory within a few minutes after it had been killed. The doe had been suckling a fawn and had a large supply of milk. By massaging the milk into an exposed milk well, 25 cc. was collected and frozen for later analysis at the College of Agriculture at Davis. The following table
(217 )
218 CALIFORNIA PISH AND GAME
compares the composition of this sample of deer milk with the average
composition of milks of antelope, goat and cow :
Total
solids Ash Fat
Specific per per per
Animal gravity cent cent cent Authority
Deer . ___ 1.046 20.4 1.44 8.3 Present analysis
Antelope _ 24.9 1.3 13.0 Einarsen, A. S., 1948.
The Pronghorn Ante- lope. Wld. Mgt. Inst., Wash., D. C, p. 110.
Goat . 1.0305 13.2 .85 4.07 Heineman, P. G., 1919.
Milk. W. B. Saunders Co., Phil. & London, p. 70.
Cow 1.0313 12.73 .72 3.G8 Heineman
Chemically the milk of deer proves to be rich in total solids, ash and fat, much like antelope milk. By contrast, goat and cow milks are much lower in solids, fats and in nutrient value. — Herbert L. Hagen, Museum of Vertebrate Zoology, University of California, Berkeley, October, 1950.
OBSERVATIONS ON FAILURE OF GAMBEL QUAIL TO BREED
The failure of quail to nest during dry years has been reported by many people. Leopold (Game Management, cl933, p. 28) states: iC . . . during periods of drouth Gambel quail coveys fail to pair off and nest. Apparently in such instances the disposition to breed is inactive for lack of some stimulus associated with normal weather, food and cover, but the abnormal condition does not visibly affect the health of the adult birds. No one has proved that drouth is actually the cause of failure to breed, or through what deficit in food, cover, vitamin, or mineral it operates to this end."
The reports in the literature are usually for isolated areas and rep- resent isolated observations. During the spring of 1950 it became evi- dent to the fish and game personnel working in the Colorado and Mojave Desert region that throughout most of this area the Gambel quail (Lophortyx gambeli) were not nesting. The birds did not pair off and remained in the large winter coveys. As the spring progressed there was a noticeable absence of young chicks or paired-up birds. During this period several birds were collected from different localities throughout the desert. Some of the male birds possessed slightly enlarged testes, but there was no sign of development of the female reproductive organs. The crop contents were analyzed by the Division of Fish and Game food hab- its laboratory and showed that seeds and insects were making up the diet of the birds but that no green feed was present,
Throughout most of the Colorado and Mojave Desert there was less than 2 inches of rain during the 1949-1950 season. Almost all of this pre- cipitation fell during December and January when the weather was too cold for any growth to occur.
NOTES 219
On July 6, 1950, heavy rains fell in the Piute Mountains in the vicin- ity of the Lazy Daisy Well. Sprouting annuals appeared shortly follow- ing this rain. There were a few light showers in August and early Sep- tember and preen feed was plentiful from a few days after the rain on July 6th until September 10th. Young quail 10 to 14 days old were ob- served during the middle of September.
Normally the quail in this area start to mate the first of April, so the breeding season was delayed approximately four months. Up until this time there had been no young birds observed in this area. The only places in the Mojave-Colorado Desert where young birds were found were adjacent to spots where preen feed occurred, around the border of the desert, and at a few locations at higher elevations in some of the desert mountain ranges. From these observations it would seem that a lack of green feed and the vitamins it contains is responsible for the birds failing to pair off and nest. Evidently if preen feed is supplied during the breed- ing season the birds are stimulated and begin to breed. — Wallace Mac- gregor, Jr., and Manley Inlay, Bun an of Gamt Const rvation, California Division of Fish and Cum, . November, 1950.
IN MEMORIAM SAM R. GILLOON
Assistant Chief of Patrol S. R. Gilloon, in charge of the Sacramento Division of the Bureau of Patrol, passed away on October 27, 1950, at the Veterans' Hospital, Fresno. He had suffered for some time from an unidentified ailment.
Sam Gilloon entered state service on April 1, 1925, as a deputy in the patrol department. He was stationed in Siskiyou County, and was promoted to captain in 1928, with headquarters at Mt, Shasta. In 1935 he was transferred to the Fresno District, where he served as captain until 1948, when he was promoted to assistant chief, in charge of that district. Upon the retirement of Assistant Chief C. S. Bauder, Gilloon was placed in charge of the Sacramento patrol district.
Sam Gilloon was a very active and most capable enforcement officer, well liked and respected by his men. He had many friends and associates who join the department in extending sincere sympathy to Mrs. Gilloon. — L. F. Chappell, Chief of Patrol, California Division of Fish and Game. January, 1951.
( 220 )
REVIEWS
Handbook of Freshwater Fishery Biology
By Kenneth I). Carlander; William C. Brown Company, Dubuque, Iowa, 1950;
v + 281 p., 5 charts ; $4.50.
This hook is without question an outstanding contribution to the literature on fresh-water fishery biology. It is the first major compilation summarizing a vast wealth of previously scattered data into a convenient form for comparative and reference purposes. The title may be misinterpreted by those who think of a fisheries handbook in terms of a manual or textbook ; instead, this actually is a handbook or source book for quick reference to data on fresh-water fishes. Periodic supplements to the handbook are planned to keep the compilations up to date.
Contents of the present volume are divided into several sections as follows: Introduction and Instructions for Reading the Tables; Suggestions for Conducting a Simple Age and Growth Study; Life Histories (by species) ; Population Data; Con- version Tables ; Literature Cited; Index; and Appendix of Alinement Charts and Nomographs.
The section on Life Histories (by species) represents the monumental task of compiling ". . . as completely as possible all data on growth, length, weight, and various length relationships on all species of fresh-water fishes found in the United States and Canada." and then assembling this data in a standard form for easy comparison. This work alone will save fisheries workers untold hours of duplicating each others work in compiling the same material. Mr. Carlander admonishes his readers quite clearly, however, that ''These summaries will not serve as a substitute for reference to the original papers in any detailed life history study." He also cautions that "Not all of the data in the tables are of equal value" as "Some represent careful, detailed studies and others are mere chance observations."
The section on Population Data includes creel census figures of catch per hour, annual yield per acre, and standing crop. These data were accumulated in connection with other bibliographical work and no particular effort was made at a complete coverage. Nevertheless, much valuable information is included and, of greater impor- tance, a start has been made in the compilation of comparative statistics for creel census data evaluation. If fish management work is to be carried forward in an intel- ligent fashion there is a definite need for evaluating yardsticks by which the results of the use of stocking, environmental control and various other methods of improving fishing can be compared and analyzed.
Conversion tables are included for inches by tenths and by eighths to the nearest millimeter, for ounces to grams, for pounds by tenths and by hundredths to the nearest gram, and for ounces by tenths to hundredths of a pound. There are tables for con- verting lengths and weights of preserved fish to live lengths and live weights. In addition there is a table of the reciprocal method of calculating the condition index whereby the factor from the table corresponding to the length of the fish in millimeters when multiplied by the weight of the fish in grams gives the condition index. The same table can also be used to determine the condition index from English measurements.
An idea of the scope of the book can be had from the fact that there are 1,112 references listed in "Literature Cited." These include waters and fish from all sections of the United States, much of Canada and many from other countries as well. Carlander deserves a rousing cheer from all fresh-water fishery workers for the magnitude of this work.
In my opinion this book will make a worthwhile and very useful, if not indi- spensable, addition to the library of all biologists, conservationists, and research workers dealing with fresh-water fishes. — Scott M. Soule, California Division of Fish and Game.
(221)
222 CALIFORNIA FISH AND GAME
The Pursuit of Plenty: The Story of Man's Expanding Domain By A. G. Mezerik ; Harper & Bros., New York, xi + 209 p. $2.50.
Here is an interesting, highly recommended book concerned with the struggle between the people's right to a fuller life and the private interests which seek to exploit for profit while preventing the full development of resources. The criticism is directed at such groups as the "professional economizers" who will pollute the water or the air in preference to slightly reducing the annual dividend. The answer given by Mezerik is the extension of agencies such as the TVA or similar, stronger regional planning organizations which, by national and international integrated resource development, will meet the problem of the expanding population. This book is good for the professional wildlife worker whose perspective is clouded by the maze of petty details. We could well adopt as a motto one of Mezerik's basic concepts that ". . . nowhere can natural resources be evaluated as materials separated from the social organization of the people who are to use them." — R. M. Paul, California Division of Fish and Game.
Name That Animal
By Ernest C. Driver, drawings by Olive Driver ; The Kraushar Press, North- ampton, Mass., 1942, revised 1950, 558 p., 113 p. of line drawings, $6.50.
This is an initial attempt to combine under one cover and by one author the means by which the student and the curious can identify the more common land and fresh-water animals found in the United States. That there is a need for such a book is beyond dispute.
As acknowledged by the author, emphasis has been placed on the species occurring east of the Rockies. This is quite noticeable for one finds that certain species indigenous to California are missing and that notable California references are absent from the bibliography.
The author has arranged the 11 phyla of land and fresh-water animals into 14 groups in consequent chapters. There is a general introductory discussion of each group. This is followed by line drawings of individual species or labeled plates show- ing morphological characteristics of the group and by a key to the identification of animals included in that group. Two chapters are devoted to egg and track identifica- tion. Accompanying each chapter is a list of references. It is felt that many of the line drawings are too sketchy and that considerably more time should have been spent on the illustrations.
One should find that with this book he can key an unknown animal down to species or at least to a point where he will know where to look in available literature for such identification. A zoologist desiring the finer details of classification will undoubtedly find the book's value limited but to the amateur it is recommended.— Howard R. Leach, California Division of Fish mid Game.
Field Book of Seashore Life
By Roy Waldo Miner; G. P. Putnam's Sons, New York. 1950, xv + 8SS p., 251 black and white + 24 colored plates. $6.
This is truly an excellent volume. Dr. Miner, who is now curator emeritus of living invertebrates, American Museum of Natural History, has drawn upon a life- time of observations in preparing it, and this is reflected in the complete descriptions and natural history notes. The book includes more than 1,300 species of marine inverte- brate animals commonly found in the waters of the Atlantic from Nova Scotia south to Cape Hatteras ; from the upper tide limit to the edge of the Continental Shelf at a depth of 600 feet. Each species discussed is represented by an accurate line drawing and in addition many are illustrated in color.
In the introduction the author gives a brief explanation of scientific classification. There are as well short sketches telling where and how on the seashore one may find many of the common forms. Quick and easy methods of capture and preservation are suggested.
The geographical area covered in the scope of the book is relatively small and many of the animals discussed are endemic to it. This should not detract, however, from the value of the book as a reference for biologists in other localities.
Very early in the text occurs the statement, "The book is intended first of all for the layman . . .," but common names, which the nonscientist can understand and then use himself in telling a friend of a particular seashore find, are noticeably lacking throughout with the possible exception of the section on shells. Dr. Miner excuses this lack of common names with several statements including, ". , . the
REVIEWS 223
so-called popular name may seem easier to remember, but it is loosely applied, and often includes different species under the same current appellation." While this is unquestionably true, the use of scientific names in a book for the layman seems to be carried to extremes in this case. There are many places in the text where for fifty or more pages no popular name occurs.
A man of Dr. Miner's qualifications should be the logical person to set up a system of acceptable common names for these invertebrates and what better place than the present volume to inaugurate such a plan. However, any slight disappointment which the layman may experience over lack of common names will probably be more than compensated by the thoroughness of the text.
This volume is definitely recommended to anyone who has even the slightest interest in the seashore and the animal forms which may be found there. — John E. Fitch, California Division of Fish and Game.
Streamer Fly Fishing in Fresh and Salt Water
By Joseph D. Kates, Jr.; D. Van Xostrand Company, Inc., New York, 1950; xvii + 402 p. ; $5.
Apparently this is the first book to be devoted exclusively to streamer and buck- tail fishing. By the author's definition, each is a type of "fly" which does not represent an insect but "whose shape and intended action is to represent a baitfish." The streamer possesses a predominantly feathered wing; the bucktail a predominantly haired wing. Such flies are well known especially as early season lures and as takers of big fish.
The first part of the book deals with definitions, the development of streamer fishing, the reasons why fish take them, methods of fishing, and tackle. It includes chapters on fast and slack water fishing, and on salt water fishing in the west, east, and south. The chapter on western salt (and brackish) water fishing discusses salmon (especially silvers), cutthroat, steelhead, striped bass, and shad.
The second part, almost half of the book, is a detailed account of the history and "authentic" dressing of more than two hundred streamers and bucktails. Wherever possible, Bates has described the flies directly from original patterns and much of their history has been obtained from the originators. Californians will find special interest in the development of such Klamath River steelhead flies as Peter Schwab's wire- bodied bucktails, C. Jim Fray's optics of Eel River fame, and the older flies such as the Railbird and Improved Governor. Incidentally, one fly in the series, the "Leech Streamer" is unique in representing a leech or bloodsucker instead of a minnow. (The term "fly," it will be seen, is a very inclusive one today. Flies have now been tied to imitate insects, crustaceans, worms, and fish ; and at least one pattern purports to represent a gob of salmon eggs.)
The sections on methods of use are easy to follow and should be helpful to most anglers. However, the detailed discussions of streamer design, and the reasons for such designs and their selection, tend to bog down in minutiae which will have appeal only to the extremely technical angler and fly-tier. The book is obviously written for such men. The neophyte or more casual fisherman will probably read only the more general sections, and will do well to keep in mind the author's own conclusion : "Of all that this book contains, the very essence of its teaching is to suggest that the angler select patterns of a size and type similar to the prevalent baitfish ; and then to fish his fly as that baitfish habitually swims . . ."
There are two good color plates by Ellen Wagstaff and attractive line drawings by Milton J. Weiler. The book is indexed. — William A. Dill, California Division of Fish and Game.
Natural History of Marine Animals
By G. E. MacGinitie and Nettie MacGinitie ; illustrated by the authors, Marcella Carter, and Lucina Stanford ; McGraw-Hill, New York, 1949, 473 p., 282 figs. $6.
The MacGinities' book is an introduction to the ecology and classification of marine animals. The emphasis is placed on the animal life of the North American Pacific shores, but the discussion is carried to all oceans. On the whole the book does what it is aimed to do — answer questions of a general nature about the animals of the water and beach wTorlds. Much of the material was obtained from field work done along the shores of Southern California, but substantial information is drawn from standard texts of the marine sciences.
It will become obvious that liberal use of the authors' own field observations elevates this book above many zoology books. This valuable feature is designed to show research students that animals can be studied in their environment and that conclusions
224 CALIFORNIA FISH AND GAME
about animal conduct should be made from such observations and not those made in the laboratory. There are numerous references to field methods which will he inter- esting to those ready to study or obtain specimens in the wild. Simple definitions and explanations keep this hook from being truly technical. Withal the hook can he useful to the professional biologist, although it is not intended for him, by summarizing the classification of animal groups and the principal aspects of marine ecology. This latter subject is discussed under the topics of food, growth rates, sense organs, comparisons between sea and land animals, relationships of animals, and the ocean as an environ- ment.
The format of this book is similar to others in the well-known series by the publishers. The figures are good and supplement the many excellent photographs. Some irregularities occur. The remora is called a pilot fish on page 14. but on page 432 it is referred to as a shark sucker. On page 7 there is a statement that marine animals need less food than land animals; this astonishing fact is not explained until page 21. The discussion on succession hardly applies to marine groups. A series of fish definitely not in the category of flatfish is included under that heading.
It will behoove students and teachers of zoology, one group for whom the book is intended, to read it carefully. They will discover that irrelevancies, some discon- tinuity, and carelessly worded statements detract from the book's value. — Robert L. Eberhardt. California Division of Fish and Game.
A Modern Dry-Fly Code
By Vincent Marinaro ; G. P. Putnam's Sons, New York. 1950 ; 269 p. $4.
There is a tendency among American dry-fly fishermen today to scorn the Halford theory of "exact imitation" and the necessity of having a multiplicity of flies each designed to match a particular natural. We find numerous authors decrying wings as useless appendages and a growth in the use of the impressionistic and the "attractor" tlies. Part of this may be due to the continued influence of such writers as LaBranche, with his emphasis on presentation rather than pattern, or Hewitt, who advocated the use of hackle flies alone. An even more probable reason is the fact that good success can usually be achieved on most American streams by using only a few patterns (or sizes) of flies. This is especially true on many rapid western streams where there are few large hatches of insects, where one merely fishes the water, and where — in the reviewer's opinion — trout will often strike at almost any fly if it is properly presented. Hence we find some very successful one-fly fishermen.
Marinaro admits this general premise. However, he then proceeds to call atten- tion to the peculiar problem of the hatch, and the failure at times of even the best fisherman to succeed in taking fish despite a host of surface-feeding trout. It is at such times that he feels that the exact imitation is indispensable. Or again when one fishes ". . . the clear calm waters, the slow smooth currents, the long glides and flats . . ." such as one finds on the limestone streams of Pennsylvania. These are the stable, spring-fed, weedy streams resembling the English chalk streams. They are rich in food, produce large trout, and offer difficult fishing. We can probably find similarities in some of the northeastern California rivers. At any rate it is here that we find the selective trout, and it is for the angler for such trout that Marinaro expounds his theories. Among them are his ideas that the body of an imitation dun is superfluous but that the wing is its most important part, and that rises to extremely minute float- ing insects are often mistaken for nymphing patterns.
This book is not for the "chuck and chance" fisherman. It is written by an angler- entomologist, a man to whom hooks larger than No. 14 are "outrageous," who speaks glibly of the "rise-form," and who discusses taking three-pound trout on 8 X gut (less than i lb. test) or on No. 22 flies. Obviously the book will have appeal to only a limited audience, but it will be interesting reading to the scientific and unhurried angler. It has something of the style of the English writers and at times seems stilted or overly formal. As compensation for this, Pearce Bates' frequent marginal illustrations have a quiet humor that relieves the formality of the text.
The forepart of the book is devoted almost entirely to the theory of exact imi- tation and the presumed vision of the trout. The latter chapters discuss specific flies, their life histories, and methods of dressing the artificials. The book delves fairly deeply into entomology, but there has been an unfortunate capitalization of the specific name of every insect mentioned. — William A. Dill, California Division of Fish and Game.
REVIEWS 225
Flies
By J. Edson Leonard ; A. S. Barnes and Company, New York, 1950 ; xii -f 340 p. ; illustrated. $.",.00.
The subtitle of "Flies" reads : "Their origin, natural history, tying, hooks, pat- terns and selections of dry and wet flies, nymphs, streamers, salmon flies for fresh and salt water in North America and the British Isles including a dictionary of 2,200 pat- terns." There are chapters on hooks, tools and materials. Separate chapters describe the design and methods of dressing the major types of flies listed above ; an additional one covers the construction of the larger fly-rod lures such as the hair and cork bugs. In the penultimate chapter the author discusses natural insects and crustaceans. Two charts show the recognition characters of both immature and mature forms. There are descriptions of many of the best known naturals, notes on their life-histories, charts showing emergence dates (eastern), and correlations of the naturals with artificials. Several charts on the feeding habits of trout and other fishes are reproduced from fish- eries papers. The last chapter is a very inclusive listing of fly patterns, most of it in tabular form and cross-indexed. The book contains eight color plates and 30 black and white drawings by the author, and 24 photographs by Jack Leonard and the Cameo Studios. An appendix includes letters from numerous fly-tiers discussing original or favorite patterns for specific localities. There is a bibliography and an index.
This, then, is the plan of the book and it is a good one. What has it omitted? The chapter on fly design begins with the interesting history of the development of artificial flies, but it is a spotty account and terminates abruptly. One wishes that the author had a fuller discussion of the many contributors to basic fly theory and design. One also wishes that the dictionary of patterns had included the name of the originators and something of the pattern's history whenever known. Of course, this would be an encyclo- pedic task but the blurb indicates that the book has this scope. There are other omis- sions. One wonders why an otherwise thorough chapter on hooks does not even mention the double hooks often used on salmon flies, nor the "over and under" hook, nor give a comparison of the American and the British "new scale" of hooks. It is a surprise to see flies of the "Irresistible" or "Rat-faced McDougal" type omitted, and a "complete" book on flies should surely mention some of the newer developments such as the use of Gantron, Lee Wulff's Form-A-Lure flies and the Garland bodies. The indexing is ade- quate although there are a number of incorrect paginations. In the tabular portion of the dictionary it would have been helpful to have the column headings repeated on each page. The table on hook eyes (p. 15) is extremely puzzling; it seems to have been entirely unedited. Among the minor errors one notes that on p. 34 the author obviously meant to refer to W. C. Stewart instead of to W. C. Prime. His statement (p. 78) that : "The Variant is purely an American version of the dry fly ..." might well be ques- tioned by the British. The term "compressed" (for flat-bodied nymphs) is used instead of the zoologically correct "depressed." There are a number of minor inconsistencies between text, tables, and figures.
This is such a good book that it may seem unfair to have devoted this much space to pointing out its imperfections. However, my criticism of the omissions is engendered in large part because of what one is led to believe by the publisher's description on the jacket : "Definitive, complete . . . the only comprehensive, encyclopedic treatment of Hies ever published, it integrates every related aspect of the subject . . . monumental, conclusive . . ." Leonard's book does approach this description, but it does not attain it. In fact it is simply because he has been so exhaustive that one expects him to be completely so. His book represents a prodigious amount of detailed work, and is extremely well executed as a whole. His drawings are excellent. His descriptions are clear. I think most fly-tiers will want to own it. — William A. Dill, California Division of Fish and Game.
The Sandhill Cranes
By Lawrence H. Walkinshaw ; Cranbrook Institute of Science, Bloomfield Hills, Mich., 1949, 202 p. .$3.50.
The author spent portions of 15 years gathering data on four subspecies of sand- hill cranes — the lesser, greater, Florida and Cuban — in Alaska, the United States, Cuba and the Isle of Pines. The text covers various aspects of crane behavior and life history, much of which is based on observations of a captive female greater sandhill that Walk- inshaw raised from a fledgling. Several plates of excellent photographs of cranes and crane habitats are included. Two appendices follow the text, the first a key to the cranes of the world and the second a list of distribution records for each subspecies.
This book presents a great deal of valuable information on sandhill cranes, and a significant amount of the material, such as hatching dates, incubation period and
226 CALIFORNIA FISH AND GAME
hatching success, appears to be new to crane research. In discussing populations and possible management, it is slated that protection of the Florida subspecies, which is estimated to include about L'.(;r>(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 2J2 |
||
|
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
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