APR \ J [CALIFORNIA FISH- GAME rcONSERyATION OF WILD UFE THROUGH EDUCATIONT 81244 STATE OF CALIFORNIA DEPARTMENT OF NATURAL RESOURCES DIVISION OF FISH AND GAME San Francisco. Caliiornia EARL WARREN Governor WARREN T. HANNUM Director of Natural Resources FISH AND GAME COMMISSION H. H. ARNOLD, President Sonoma LEE F. PAYNE, Commissioner WILLIAM J. SILVA, Commissioner Los Angeles Modesto HARVEY E. HASTAIN, Commissioner PAUL DENNY, Commissioner Brawley Etna EMIL J. N. OTT, Jr. Executive Director Sacramento and San Francisco CALIFORNIA FISH AND GAME CARLTON M. HERMAN, Editor Berkeley Editorial Board RICHARD S. CROKER San Francisco BRIAN CURTIS San Francisco JOHN E. CHATTIN Berkeley California Fish and Game is a publication devoted to the conservation of wildlife. It is published quarterly by the California Division of Pish and Game. All material for publication should be sent to Dr. Carlton M. Herman, Editor, Division of Fish and Game, Strawberry Canyon, University of California, Berlceley 4, California. Manu- scripts should be typed, double spaced, and conform to the style of previous issues. The articles published herein are not copyrighted and may be reproduced in other periodicals, provided due credit is given the author and the California Division of Fish and Game. This publication is sent free of charge to interested persons, who may have their names placed on the mailing list by writing to the editor. Subscriptions are for one year and must be renewed annually. A postcard will be included with each October issue for renewal of subscriptions. Subscribers are requested to notify the Division of Fish and Game, University of California, Berkeley 4, California, of changes of address, giving old address as well as the new. California Fish and Game "CONSEBVATION OF WILDLIFE THROUGH EDUCATION" Volume 34 ISSUED JANUARY 30, 1948 No.l TABLE OF CONTENTS Page Summary of Recovery of California Sardine Tags on the Pacific Coast J. F. Jansen, Jr. 3 Basking Shark Fishery Revived in California J. B. Phillips 11 Breeding Season and Productivity in the Interstate Deer Herd J. E. Chattin 25 The California Valley Quail in New Zealand H. A. Hjersman 33 Notes — Sablefish Run at Monterey Bay K. W. Cox 37 Rearing Marine Fishes in the Laboratory J. L. McHuGH and B. W. Walker 37 Occurrence of the Black Skipjack (Euthynnus lineatus) oif South- ern California Phil M. Roedel 38 Extension of the Range of Liivaris imperialis Rafinesque W. E. Ripley 39 Retirement of A. E. Burghduff A. C. Taft 40 Retirement of Louie L Phillips A. C. Taft 40 Reports 41 (1) 81244 SUMMARY OF RECOVERY OF CALIFORNIA SARDINE TAGS ON THE PACIFIC COAST By John F. Janssen, Jr.,^ Bureau of Marine Fisheries, California Division of Fish and Game From 1936 to 1942 the California Division of Fish and Game eon- ducted an extensive tagging program to measure the movements and abundance of the Pacific sardine {Sardmops caerulea) . The results of this work, based on returns through the 1943-44 fishing season, were published in Fish Bulletin No. 61 (Bureau of Marine Fisheries, 1945). Since 1944 additional recoveries have been made each year but by the 1946-47 season the number dropped to an inconsequential figure. Because few, if any, returns may be expected in the seasons to come it seems advisable to present the data for the seasons 1944-45 through 1946-47 and to sum up the results of all recoveries. The cooperation and assistance rendered by the fishing industry in California as well as that rendered by government agencies and the industry in Oregon, Washington and Canada are gratefully acknowl- edged. Between March, 1936, and August, 1942, the California Division of Fish and Game tagged 120,948 sardines in California and Lower California waters. Tag recoveries from these fish through May, 1947, have totaled 8,497. In studies of movements of sardines, however, only 115,489 of the fish tagged were considered. These fish yielded 8,425 recoveries. During the period when tagging techniques were being devel- oped there was at times an excessive mortality among the fish. On a few occasions fish were tagged which were too small or in too poor condition for survival. Occasionally an unusual number of predators caused exces- sive mortality immediately after tagged fish were released. Due to these complications tagging groups totaling 5,459 fish yielded too few returns to justify their consideration in any analysis. Although a few sardines are caught along the California coast in the spring and summer months, the majority are landed in the fall and winter. In Oregon, Washington and British Columbia they are caught in the late summer and fall months. It is therefore convenient to com- mence the tag recovery year on June 1st. Tables 1, 2 and 3 are continuations of Tables 1, 2 and 4, pp. 11-15, of Fish Bulletin No. 61. These tables show the actual number of tags recovered by regions from sardines released off Central, Southern and Lower California as well as the number of tag recoveries which could have been expected had recovery efficiency been 100 percent. Recoveries by regions from 1936-37 through 1943-44 are listed. These figures cor- respond to the subtotals given in the tables in Fish Bulletin No. 61. Following the recoveries by region through 1943-44 appear the recoveries by season for the three succeeding seasons. In addition, the totals for the period from the beginning of the tagging work through 1946-47 are shown. These tables do not include recoveries made in the season of tagging. 1 Submitted for publication August, 1947. 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I. (U V J3 > E o u 3 > re -a I . E ^ 3 (A Z V a> <0 i > o o o w 0} CC < •+- o c o ♦» « o o • 1 138.5 5.8 3.1 ^ Ol^ 229.2 419.2 87.7 15.4 Ico a OO CO 1 g^N Oi '<« ^ CO *-4 ■o 1 »0 Ci ' s s o W3 CO »OM • I W3 COt-I CO CO CO 3 »OCC^H O COTt. O CI •^ va lo »o 1 o C5 CO CS tT o 1 o o Ci -i 5 C3 o « RECOVERY OP SARDINE TAGS 7 Table 4 supplements Table 12, p. 23, of Fish Bulletin No. 61. It shows the percentage efficiency of recovery of sardine tags by region for the seasons 1944-45 through 1946-47. San Diego recovery efficiencies are not included as no tags were recovered at this port during the period in question. Fish Bulletin No. 61 contains a complete discussion of methods used to determine the efficiency of recovery within each region. TABLE 4 Percentage Efficiency of Recovery of Sardine Tags by Region and by Season Region of recovery Season British Columbia Washington Oregon San Francisco Monterey Ran Pedro Large Tags 1944-45 40 40 57 20 77 69 66 1945-46 71 1946-47 45* Small Tags 1944-45 40 40 53 21 72 66 61 1945-46 64 1946-47 40* 60* • * Conservative estimates. No efficiency tests were conducted in this season. The present discussion does not include recovery in California of sardine tags released by other than California investigators. Kecovery of Canadian tags in California has been fully treated in reports by Hart (1944, 1945) who has shown there is a movement of sardines from Canadian fishing grounds to those of California. The large numbers of fish involved in this movement indicates a definite southward migration. Fish tagged by the California Division of Fish and Game in Mexican waters have been retaken in Pacific Coast sardine fisheries as far north as Washington (Table 3). Sardines tagged in California waters have been recovered in all the California fisheries as well as in all the sardine fisheries in the Pacific Northwest (Tables 1 and 2) in sufficient numbers to indicate a northward movement of a substantial proportion of the stock. Other reports have pointed out that as a rule the larger fish make the longest northward migration. Sardine tag recoveries in the past three seasons have not required a revision of conclusions presented in previous reports. It is interesting to note, however, that one Mexican tag was recovered as far north as the State of Washington. This tag was put into a sardine of 170 mm. total length. It was released in San Quentin Bay, 145 nautical miles south of the international boundary, and recovered five years and ten months later. No tag recoveries have been reported from reduction plants in Lower California. Facilities for recovering tags were in operation there for only a brief period and the quantity of sardines processed in Mexico is small in comparison with other localities along the coast. The length of time that some tagged sardines have remained at sea before recapture is indicated in Table 5. This table lists the California sardine tags which have been recovered from fish released six or more years earlier. One tag was out over seven years and eight months. The 3 — 81244 8 CALIFORNIA FISH AND OAME fish which bore it Avas 240 mm. total length when tagged, or about 205 mm. standard length. It is estimated that this fisli was in its second or more likely its tliird year of life when released oft' Southern California. TABLE 5 Sardine Tag Recoveries Six or More Years After Release Date tagged Date recovered Elapsed time Region tagged Region recovered Total length of fish when years months days tagged in mms. Dec. 15, 1937 Feb. 15, 1938 Aug. 28, 1945 Oct. 12, 1945 Dec. 19, 1944 Oct. 30, 1944 Feb. 9, 1945 Feb. 26, 1946 Aug. 18, 1944 Aug. 8, 1944 July 18, 1943 Dec. 10, 1945 Aug. 28, 1944 Oct. 12, 1945 Nov. 1, 1945 7 7 6 6 6 6 6 6 6 6 6 6 6 8 7 10 8 8 5 2 2 1 1 0 0 0 13 27 4 23 4 14 13 3 29 12 27 19 3 Southern California... Southern California... Southern Cahfornia... Southern California... Southern California... Central California Southern California... Southern California... Southern California... Lower Cahfornia Southern Cahfornia... Central California Lower Cahfornia .. British Columbia Monterey 240 215 Feb. 15, 1938 Feb. 7, 1938 British Columbia Monterey 220 205 June 5, 1938 Monterey 155 Sept. 12, 1939 June 5, 1938 British Columbia Monterey 220 180 June 5, 1938 May 19, 1937 Oct. 28, 1939 San Francisco British Columbia San Pedro 180 220 145 Aug. 1. 1938 Sept. 23, 1938 British Columbia Monterey 165 240 Oct. 28, 1939 Monterey. ... 175 It was recovered in the Brifish Columbia fishery. Another tag out over seven and one-half years, also inserted in a fish off Southern California, was recovered at Monterey. This fish was 215 mm. total length or about 183 mm. standard length when released. It was perhaps in its first or second year of life. These fish were therefore 8 to 11 years old when caught for the second time. A comparison of the number of tag recoveries with the number of sardines tagged is misleading unless losses due to tagging mortality and to incomplete recoveries are given consideration. How these factors affect the percentage of tags recovered is shoAvu in Table 6. This table includes the same fish as Tables 1, 2 and 3. However, unlike the other tables it also lists recoveries made in the season of tagging. Recoveries made in season "0" can be greater than the combined recoveries of succeeding years. If the fish are tagged on the fishing grounds early in the season they are subjected to the fishery for a rela- tively long period before they have had an opportunity to become well dispersed. On the other hand, if they are tagged very late in the season recoveries will be few in season "0." A tagging mortality of 43 percent was assigned to the fish in Table 6. This is considered conservative. It represents the weighted average mortality of the fish in Table 13, p. 27, of Fish Bulletin No. 61. Table 6 includes all fish included in that table and in addition some others selected on the basis of less rigid standards. From the total number of tagged fish (115,489) used in our studies 8,425 tags were recovered or 7.3 percent. Only 65,828 fish, however, were considered effectively tagged (not lost through tagging mortality), and if recovery methods had operated at 100 percent efficiency 14,610 tags would have been recovered or 22.2 percent of the fish effectively tagged. Tag recoveries during the past three seasons confirmed conclusions previously drawn, that there is a general interchange of the sardine population along the Pacific Coast. In addition these later recoveries EECOVERY OF SARDINE TAGS (O _l < c « E «> > o (0 .£ •5 T3 « M D M a> _c •5 t. (S CO 73 4) □) Ol n I- (0 .2 0) > o o 4) QC C n (A O 10 (0 0) cc T3 0) +• M 3 — 1 ■o < o ^ p. T3 CJ -S Sfb 2 .2.0 > _ ■HS§ r H TJ V i. n a E o O M .2 4> > o o « 73 C n M 4) 10 n « DC "(5 3 +> O < o .£ >.>' go S izJ O 2; S ^ u5 r- CO (M »oc^ ^ Tt* t^ -^ CO z 5 a UDOfM CT> o o scicta o o o o u a> i^ bC tfl u &0 bO ca 10 CALIFORNIA FISH AND GAME have indicated tliat fish released in ^Mexican waters will move as far north as the Washinprton coast, that some sardines may be retaken more than seven years after taf^frinj]^ and will have reached an ajre of 8 to 11 years. About 22 percent of the effect ivol}^ tajr;:red fish were retaken by the fishermen during the years covered by the investigation. References Bureau of Marine Fisheries 194ij Results of tasfritifc experiments in California waters on the sardine (Sar- dinopH caerulea). Calif. Div. of Fish and Game, Fish Bull., no. Gl, 90 pp. Ilart, .John Lawson 1944 Pilchard-tagging and pilchard-tag recovery from 19.36 to 1943. Report, British Columbia, Provincial Fisheries Department, 1943, pp. 43-;j2. 194.5 Summary account of Canadian pilchard tagging results. Fisheries Research Board. Canada. Progress reports, Pacific Coast Stations, no. 64, pp. 51-52. Janssen, John F., Jr. 1938 Second report of sardine tagging in California. Calif. Fish and Game, vol 24, no. 4, pp. 376-389. BASKING SHARK FISHERY REVIVED IN CALIFORNIA By J. B. Phillips ^ Bureau of Marine Fisheries California Division of Fish and Game Introduction The fishery for basking sharks, Cetorliinus maximus, was revived in the fall of 1946, following a period of several years of relative inactiv- ity. As in the past the scene of greatest activity has been Monterey Bay, but a second fishing area developed between San Luis Obispo Bay and Morro Bay, about 100 miles to the southward. In former years Monterey was the port at which was landed the bulk of the sharks taken in Monterey Bay. Now it is the port of Moss Landing, 20 miles to the northward. Two sardine plants have done all the processing there. In the San Luis Obispo area most of the sharks have been landed at Morro, with some at Pismo, 1 i^-*- ■^ Figure 1. Basking shark on truck for transportation to processing plant, after being hauled up slip from water. Moss Landing, March 22, 1947 and processed by a tallow plant near San Luis Obispo. On some occasions surplus carcasses with livers removed at Moss Landing have been trucked to a reduction plant at Petaluma. The meal was used in chicken feed mixtures. At the start of the present season (September, 1947) some 1 Submitted for publication September, 1947. All photographs by author. (11) 12 CALIFORNIA FISH AND GAME surplus carcasses, with livers removed, were also trucked to a reduction plant in Fresno. Durinfir the period September, 1946, to May, 1947, about 300 basking sharks, averaging approximately one and one-third tons each in the round, were taken along the California coast. This season, is the period during which these sharks are found in central California congregating in num- bers near the surface of the ocean. This concentration makes possible a commercial fishery based on harpooning. Reason for Revival The primary reason for a revival of the basking shark fishery is the development of new uses for the liver oil. The livers which average close to 25 percent of the total weight of the shark, consists of 60 to 70 percent oil. The oil is of industrial rather than medicinal value since it has a very low vitamin A and D content. A limited amount has been used in live- stock feeds and as a touie. Other therapeutical properties of the oil have not been thoroughly tested. It was hoped that the oil would find a market in commercial channels, such as in soap or paint manufacture. But the oil, as refined at present, does not saponify in soaps nor dry readily in paints. Trial samples sent to other commercial users of oil yielded no source of disposal and a large amount of oil accumulate in storage tanks. A limited amount of oil is now being used by Mr. L. P. Bodwell, 300 Huntington Avenue, South San Francisco, a leather specialist, who found that by proper blending the oil was satisfactory for tanning leather. Further experimentation may develop other specific uses for the oil. In ]\Iarch, 1947, Mr. Bodwell also became interested in the hide of basking sharks as a potential source of leather. Not only is there a large expanse of hide on one animal but it is from one-half to three-quarters of an inch thick in large animals. Experiments in tanning the hicles have demonstrated that a leather of pleasing appearance can be produced but further work along this line, including the possible commercial uses of such ] eather, needs to be worked out. The meal resulting from the reduction of the carcasses is mixed with animal feeds. The labor involved in the reduction process does not make the production of meal profitable, in itself. If the hide of the animal is removed for tanning into leather, the resultant meal should be enhanced in quality. The Basking- Shark Among sharks, the basking shark, which reaches a length of 45 feet and a weight of four to five tons, is surpassed in size only by the whale shark, Rhineodon typns, which is reported to attain a length of 60 feet and vreight of 14 tons. The basking shark is found in temperate and arctic waters whereas the whale shark is found in warm and tropic waters. The habits of these two sharks are very similar, both having very small teeth and long, close-set gill rakers for straining out huge quantities of larger planktonic organisms such as minute copepods and other crustaceans as well as small drifting mollusks. Both species are sluggish and prone to bask at the surface of the ocean. The whale shark may be distinguished from the basking shark by a checkerboard pattern of yellowish-white lines and spots on the back and sides, as well as several longitudinal ridges on the sides. BASKING SHARK FISHERY 13 The basking shark may be distinguished from the other sharks by the keel on each side of the caudal peduncle and the exceedingly long gill slits which extend from the back to the mid-line of the throat, nearly meeting at this point. The gill slits number five and the' teeth are small, numerous and smooth-edged. The color of the body is bluish gray to brownish gray on the dorsal surface with somewhat paler markings on" the ventral surface. As is the case with all sharks, rays and chimeras or ratfish, the skeleton is cartilaginous. The pelvic fins of the males are modi- fied to form claspers, by means of which fertilization of the eggs within the bodies of the females is made possible. A single species of basking shark is found in Arctic seas and along both sides of the Atlantic Ocean southward to the Mediterranean Sea on one side and to Virginia on the American side. In the Pacific, this shark has been reported as far south as Southern California. It is known to the various fishermen as bone shark, sunfish, sailfish, oilfish, oil shark, ele- phant shark and hoe-mother. Up to the present, the only region where these sharks have been reported to breed is in Arctic waters. The smallest specimens that have been taken in California waters have measured at least 10 feet in length. The landed specimens usually measure 15 to 30 feet in total length. Since the gill net and drag net fisheries along the California coast have not yielded any small specimens of this shark, it would appear that the nursery areas are not located along the California coast, and would most likely be found to the northward. The Fishery- History According to Jordan (1887a), who reported on the fisheries of the Pacific coast in 1880, the basking shark was valued for the oil in the liver but these fish were captured by whalers and fishermen rather by accident that by design. Apparently, Monterey was the only port along the Cali- fornia coast at which these large sharks were occasionally processed. Reporting on the activities of the Monterey "Whaling Company, Jordan f 1887b) stated: "This year (1880) 14 whales have been obtained from September to April, * * * besides two basking sharks fCefor/itwi/s maxt- mus) ; in all 500 barrels of whale-oil and eight of shark-oil. The basking shark is rare here, sometimes not seen for 20 years. This year several were seen in Monterey Bay. ' ' The basking shark fishery did not develop until 1924, except for occasional specimens that the whalers harpooned and brought to shore for processing, or specimens that became entangled in fishermen's nets, from which the livers were removed for "sun rotting." The oil thus obtained was used for mixing with crude paints or with livestock feeds. In 1924, Ernest Doelter and Henry Leppert started to harpoon bask- ing sharks in Monterey Bay as a regular sport. The harpooning was done by hand, as it is to this day, from the bow of the "Pop Ernest," a local 40-foot abalone boat. The sport was also indulged in by members of the then-existing Monterey Yacht Club, usually as guests of Doelter aboard the "Pop Ernest." The sharks were turned over to Max N. Schaefer for processing in his "Monterey Fish By-Products" plant at Seaside, near Monterey. The livers were reduced to oil and the carcasses to meal. The meal was used in livestock feeds and dog biscuits, while the oil was used 14 CAIJFORN'IA FISn AND OAME primarily for blendinp: with various animal feeds, and as a tonic called "Sun Shark Liver Oil" advertised as "Nature's own tonic." About ]028, Chester Gilkey and Bert Korf, owners of the 50-foot boat ''Two Brothers," tojjether with Tom Machado, e^juipped them- selves for harpooninji: sharks. This started as a sport and as publicity for their fishinjr-party excursions, but by 1929 the harpooning of these sharks had turned into a profitable side-line. Seven dollars a ton was paid for the sharks up to about 1930. The price then went up to $10 a ton and still later to $20 a ton, the latter price being in effect in 1938, at which time the Monterej^ Fish By-Products plant at Seaside burned to the ground. Between 1924 and 1938, the yearly average was about 25 sharks, but in one of these years approximately 100 sharks were landed. When too many sharks were brought in at one time, the Hovden Food Products Corporation at Monterey processed some of the carcasses for meal. A few sharks have been taken by this latter concern since 1938. In times past there has been a fishery for basking sharks along the Norwegian, Irish and Scottish coasts. About the middle of the Eighteenth Century, there was an extensive pursuit of this species along the New England coast and considerable quantities of the oil were produced. '■^te; Figure 2. The usual type of boat in the basking shark fishery in California. The vessel has just towed in a shark, which will be fastened to the slip along with the other sharks. Moss Landing, March, 1947. Types of Boats Boats used for capturing basking sharks range in length from 25 to 50 feet. ]\Iost of the vessels are small net boats with a fair amount of deck on the stern portion. (Fig. 2.) In addition to the regular commercial fishing-type of boats, a 30-foot cabin cruiser and two or three former Army landing barges (LCVP) 36 feet long have been used successfully at BASKING SHARK FISHERY 15 Moss Landing, In 1930 and 1931, the McDaniel brothers, new owners of the 50-foot vessel, "Two Brothers," used on several occasions a 20-foot dory from which the sharks were harpooned in shallow water. On January 27, 1931, the dory was used to harpoon two sharks in shallow water near Monterey. Four hours were required to land one of these, a 20-foot specimen. Although the Southern California swordfish boats for a number of years have used a "plank and pulpit" out over the bow, from which har- pooning is done, the boats fishing basking sharks out of the ports on Monterey Bay were not thus equipped until March, 1947. (Fig. 3.) At that time, a 13-foot extension was installed on the boat "Opal" forward of the bow with a pulpit at the end for the harpooner. Shortly after- ward, several other boats were similarly outfitted, including one of the LCVP landing barges. Another landing barge had previously been equipped with a wide platform at the bow end, that could be lowered. The harpooner stood on this platform. Two swordfish boats from Santa Barbara that started harpooning basking sharks off Morro Bay in September, 1946, were shifted to Figure 3. Harpooner in pulpit at end of "plank." At the left the harpoon is in a position ready for throwing. At the right the harpoon has been thrown. Monterey Bay, April 1, 1947. 16 CALIFORNIA FISH AND OAME Monterey Bay during the latter part of March, 1947. Each of these vessels had carried a plank and pulpit for several years. The crew of a boat consists of two men usually, one harpooner and one boat-operator. The operator of a cabin-cruiser at Moss Landing made a practice of having two harpooners who simultaneously harpooned the same shark. (Fig. 4.) This vessel, however, was no more successful than the other boats that carried only one harpooner. "<^*tC Figure 4. A cabin-cruiser type boat searching for basiling sharks in Monterey Bay. This type of boat is unusual in this fishery, as are two harpooners. Practically all boats have but one harpooner, stationed at the bow of the vessel in the position of the forward harpooner, March, 1947. During the period September, 1946, to May, 1947, about 12 boats participated in the fishery at Monterey Bay, and about half that number were engaged in the fishery centered off San Luis Obispo. Locating the Sharks The Monterey Bay boats locate basking sharks while cruising within a few miles of shore, where these animals are more often found, some- times almost in the surf. Their presence is indicated usually by the dorsal fin that projects above water, or by the shadowy bulk which may be seen in shallow water. Sometimes in the spring of the year the animals may break water. Starting in the fall of 1946, two swordfish boats from Santa Barbara harpooned a number of these sharks off San Luis Obispo and Morro Bays, operating in conjunction with a landplane that was employed to spot the animals from the air. When the pilot of the plane located sharks near the surface, the operators of the two boats were informed by radio and the plane circled the area until the vessels arrived. In this manner, BASKING SHARK FISHERY 17 the crews of the boats utilized their time to best advantage. During the latter part of March, 1947, when fishing became poor to the southward, this boat-plane combination was transferred to Monterey Bay where it operated until the sharks apparently disappeared from this area in May. According to the pilot's report, visibility is better at 2,000 feet or more than it is at 1,000 feet or less. When the water is sufficiently clear the sharks can be seen to a depth of 50 feet. From present information, there seems to be little correlation between the time of day or the kind of weather and the appearance of basking sharks at the surface. Sharks have been harpooned in the morn- ing and in the afternoon, on sunshiny days and on rainy days. In Mon- terey Bay, these sharks are apparently present in greatest abundance between October and May. Off San Imis Obispo and Morro Bays, they seem to appear about a month earlier and disappear earlier. Although these sharks are ordinarily sluggish and prone to bask at the surface, they have been observed to jump out of the water during the early part of the year. On March 22, 1947, the author observed nine of these large sharks break water near shore between Fort Ord and the Salinas river, Monterey Bay, while guest on the boat "Reliance." George Caprivize, captain, and William Madruga, harpooner, stated that such activity had been seen on a few trips previously. At such times, the sharks are not often found basking at the surface. Harpooning Equipment The methods employed in harpooning basking sharks have not changed materially from those used in the earlier days of the fishery, and are an adaptation of methods used in early whaling days. Operating from small boats, the fishermen thrust a harpoon into a whale by hand. As in the capture of a whale, the initial step in the capture of a basking shark is to " fasten on to ' ' the animal by means of a harpoon and line. After this, the animal has to be killed. The present equipment consists of a metal harpoon that fits onto the end of an 8- to 14-foot wood or metal pipe staff by means of which the harpoon is thrust into the animal by hand. Attached to the harpoon is a galvanized or stainless steel cable, one-quarter inch in diameter and several feet in length, which in turn is connected by means of a shackle and smvel to a one-half to three-quarter inch diameter, manila rope, of which as much as 500 feet may be payed out w^hile the shark is being played. In earlier days, sometimes a section of chain was used to connect the harpoon with the paying-out rope, and sometimes the paying-out rope was connected directly to the shaft of the harpoon. Usually, a 50-gallon oil drum is tied onto the retrieving rope about 250 feet from the harpoon end, to offer resistance and cause the shark to tire more quickly. During 1947, two vessels were equipped with 30-gallon, reclaimed, household water tanks, which withstood the pressure at greater depths better than the oil drums. Sometimes the outgoing rope is partially snubbed to offer resistance to the shark. When a shark has been located, the boat approaches the prey from behind, so that the harpooner may thrust the harpoon into the back in an area between the dorsal fin and the gill slits. It has been found that within this area there is less chance for a harpoon to pull out. Harpooners 18 CALIFORNIA FISH AND GAME claim that they can "roach" a shark with a harpoon if it is within 10 feet of the surface. About tliree out of four harpooned sharks will liead for the bottom of the ocean where they tr^^ to roll the harpoon out, as evidenced by bent harpoon shafts. The fourth shark is apt to take off in any direction and tow the vessel for a time. After the shark has tired sufficiently, it is hauled in alongside the boat and another harpoon is thrust into the body, as a precautionary measure in case the first harpoon is ready to pull out. As soon as possible after that, it is shot through the head with a high-powered rifle. The best place to shoot is through an eye or between the eyes. The basking shark has an exceedingly small brain encased in a cartilaginous skull, which makes it difficult to penetrate a vulnerable spot. It is uncommon practice to fill the body cavity of a dead or dying shark with compressed air, although this has been done in the past, on some occasions. It does not take much lift to keep this shark afloat, per- haps because of the large amount of oil in the huge liver. One vessel was equipped with compressed air during the spring of 1947. When used, the air, under about 60 pounds pressure, is introduced into the body cavity with the aid of a section of metal pipe sharpened and perforated at one end. It hastens the death of the animal because of the internal pressure. It also makes the cutting-out of a harpoon a little easier. After a shark has been killed, a rope is fastened around the small part of the body just anterior to the tail and the shark is towed to port, tail first. This method of towing offers the least resistance in the water. Sometimes more than one shark is harpooned from a boat on one trip. Although a vessel is equipped with several harpoons, usually the har- pooner's favorite harpoon is in the first shark and an attempt is made to cut the harpoon free, if it is not too deeply imbedded. "Where more than one shark is killed on a trip, the dead sharks are tied to a buoy until the vessel is ready to return to port, then all the captured sharks are towed at once. It usually takes about one-half hour to kill and secure a shark after it has been harpooned. Tom Machado of Monterey may have established a record when he harpooned, with the same harpoon, and killed, six basking sharks in two and one-half hours, off Del Monte Beach, Monterey Bay, March 28, 1946. Although it has always been standard practice to harpoon sharks by hand there have been at least two unsuccessful attempts to shoot a har- poon by means of a powder charge in a shotgun. Henry Porter of Mon- terey tried this in 1925, and a Moss Landing harpooner tried it in 1947. No deck guns, as used by modern whalers, have been tried. As long as a harpooner can approach within harpooning distance of a basking shark, a power gun is not needed. There have been instances where a harpooner has plunged a hea\y harpoon through both sides of an animal. It is possible that a harpoon released by compressed air might prove satisfactory because the force behind the missile can be regulated. Another development of the whale fishery, the bomblance was simu- lated by Tom Machado in 1930 when he tied a quarter-stick of djniamite to his harpoon. The short fuse was lit just before the shark was harpooned. The shark was disabled and easily killed. However, the soft liver was turned to mush, and since this is the valuable part of the animal, it was not tried again. BASKING SHARK FISHERY 19 According to Brown (1885), the primitive or typical harpoon was the sagittate or arrowheaded form, which the old-time whalers referred to as a ' ' two-flued iron ' ' ; the next step was the harpoon with one fixed barb, the "one-flued iron" and the third the iron with a movable barb or toggle which acts upon the principle of the lily-iron of the sword- fishermen. The lily-iron was evidently suggested by the adjustable bone and ivory harpoon heads of the Eskimo tribes, but it was not strong enough for most whales. It is quite satisfactory for porpoises, swordfish and large sharks. The heavy harpoons fired from deck cannon of modern whalers may have two to four heavy barbs or "flukes" hinged to the head, which open up within the whale. Harpoons employed in the basking shark fishery in California vary from standard, five-inch long, one-piece, brass darts, weighing about four ounces (often referred to as swordfish darts) to two-foot long, custom-made toggle irons weighing up to five pounds. There are a variety of designs, some only slightly different from others, in use on the different boats. I have seen three different designs on one boat, two of which had been discarded as unsatisfactory. Because of the flabby nature of the flesh and the cartilaginous skeleton in the basking shark, it has been difficult to find an ideal design that will not work out of the body during the struggles of this animal. Except for a few unsuccessful, experimental attempts to shoot a harpoon by means of a shotgun, the harpoons have been driven into a shark by hand. In all cases, the staff with which the harpoon is thrust into the animal is either pulled free from the harpoon-head, or if throwTi it is jerked free by a short rope attached to the top of the staff and the boat. The harpoons fall into three general group-types. (Fig. 5.) The first includes the dart-type harpoon with no shaft but with a shaft-seat on one side into which fits the end of a shaft on the harpoon staff. A hole near the middle of the dart permits the attachment of a steel cable, which in turn is connected to the retrieving rope coiled on the deck of the vessel. The posterior, or wing portion of the dart has a slight outward flare so that the pull exerted on the dart after it has been thrust into the animal, is on the side of the dart that is slightly convex. This reduces the chance for the dart to cut itself out of the animal. The second group of harpoon-types is the toggle-iron, or lily-iron with a head hinged near its center to a shaft. (Fig. 6.) In throwing posi- tion the head and shaft are in line, longitudinally, but when an animal is harpooned, the pull of the retrieving rope connected to the end of the shaft causes the head to pivot to a position that is cross-wise to the shaft. A matchstick inserted in a small hole through the posterior portion of the head and the shaft that it embraces, keeps the head longitudinal with the shaft until the harpoon is thrust into the animal. The outward curve of the posterior portion of the head sets up a resistance to the pull of the retrieving rope connected to the end of the shaft and the matchstick breaks permitting the head to pivot. The third group of harpoons includes the fluke-type, which consists of a sharp, wedge-shaped head and a shaft, with a pair of movable flukes on opposite sides of the shaft. One end of each fluke is hinged to the pos- terior end of the head. The free ends of the flukes are tied to the shaft in 20 CALIFORNIA FISH AND GAME SIDE VIEIA/ Hole for affachment of /fne ^^"" - ' l.„l-„-„--- ^' ' Shaft at end o-^ sfaff f/ts /r?ft> ho/e DART TYPE HARPOON TOP V/EIA/ PJi/ot / Ho/e for maichsficff fh/s enc/^//ps into opentn^ at end of^tcfff^ ^^r Eye for affcichmerjt of line TOGGLE TYPE HARPOON . Pivot FLUKE TYPE HARPOON Er7d of Staff / sea fs into opening Figure 5. Three types of harpoons used in the basking sharli fishery of Califor- nia. A variety of designs in harpoons have been used but, in general, they revolve around these three types. throwing position. After the harpoon enters the body of the animal, the pull on the shaft is resisted by the outward-flaring tips of the flukes, breaking the twine and allowing the flukes to pivot to a position that is cross-wise to that of the shaft. In the latter two groups of harpoons, the head of the harpoon is of hard metal, usually iron, while the shaft is of soft iron that will bend when the animal goes to the bottom and attempts to roll the harpoon out. The fluke-t5T)e harpoon is not common. The dart-type and the toggle-type are the most popular. BASKING SHARK FISHERY 21 Processing Livers In the San Luis Obispo area, the basking shark livers have been processed at a tallow plant located at the town of San Luis Obispo. Some of the carcasses have been processed at this plant, also. When the present season got underway in this region in September, 1947, the one plant could not handle all the carcasses, on occasions, and some were shipped to Fresno for processing. In the Monterey region, two sardine processing plants at Moss Landing have handled all the livers and the bulk of the carcasses landed Figure 6. One of the popular types of harpoons used in the basking shark fishery in California, is the toggle-iron, or lily-iron, illustrated here in throwing position at the left and in the open position as it would be in the shark, at the right. The iron loop near the end of the shaft is for attach- ment of a line, by means of which the shark can be played and later hauled in. The end of the shaft seats into the lower end of the harpoon staff. Moss Landing, April, 1947. during the past season. The dead sharks are towed to the plants, where the livers are removed and processed for oil, while the carcasses are cut uj) into pieces and reduced to meal. (Fig. 7.) Some surplus carcasses have been trucked to Petaluma for processing into meal that is mixed with chicken feeds. The liver of the basking shark is about 25 percent of the total weight of the animal, and jdelds 60 to 70 percent oil. The method of extracting 90 CALIFORNIA FISH AND GAME oil from livers, currently employed by the Ilovden Food Products Cor- poration, Moss Landing, according to Lloyd T'liillips, superintendent, is the settling tank system which some plants still use in the recovery of oil from sardines. First, water is run into the tank to a depth that will cover the steam pipes on the bottom. This water is heated to a temperature between 165 and 205 degrees, F. The shark livers, which have been chopped to a paste-like consistency, are introduced at the upper end of the long rectangular tank. As the oil breaks free, it comes to the top and gradually drifts to the lower end of the tank and overflows. When the Figure 7. Removing the liver from a basking sliark landed at Moss Landing. One lobe of the liver has been removed already and is on the table in the foreground. The man with the white cap is grasping the posterior end of the remaining lobe, and the other man is freeing the anterior end. March 22, 1947. daj^'s run is completed the heat is turned off. After several hours, the oil remaining in the tank is run off by raising the level of the water under the oil. This decanted oil is run directly to storage tanks and the remain- ing sludge is centrifuged for any remaining oil. Carcasses The carcass of the shark is cut up into small pieces and placed in a standard, steam-batch dryer with 70 pounds steam pressure and two inches of vacuum. The cooking lasts for six to eight hours. The resultant meal is light, fluffy and oily. About nine pounds of fresh carcass, with liver removed, yields one pound of the dried meal. Other controlled methods of drying the carcass to meal have proved satisfactory also. Price During the first season of this revived fishery, September, 1946, to May, 1947, fishermen have been paid 7 to 9 cents a pound for the livers. In BASKING SHARK FISHERY 23 the San Luis Obispo area, the price of 9 cents prevailed, for the most part, while in the Monterey area a price of 7 cents a pound was paid for most livers. The average weight of the livers of the sharks landed was close to 700 pounds. Occasionally, an extremely large liver will weigh close to 2,000 pounds. Just before the close of the past fishing season, the price quoted for basking shark liver oil dropped and this resulted in a price of 5 cents a pound to fishermen for livers delivered after the middle of April, 1947. At the start of the present season, September, 1947, a price of 5 to 6 cents a pound was paid in both the San Luis Obispo and Monterey areas. Nothing has been paid for the shark carcasses after removal of the liver. The returns from the sale of the meal about compensates for the expense involved in reduction. This is because of the present laborious methods of handling the huge animals, coupled with a low meal yield. Improved methods of handling carcasses, together with further experi- mentation on the use of some of the now undifferentiated waste products maj' enhance their value in the future. Other Products Preliminarj^ experiments with the hide as a potential source of leather for certain commercial uses has shown promise, and will be explored further this season. The possibility of a market for the dried fins for Chinese trade will also be explored. Some potential uses for which there is a limited commercial demand are cholic acid from bile, iasulin from pan- creas, enzymes from the digestive tract, amino acids from protein material, fish glue from the hide and squalene, a constituent of the unsaponifiable part of shark liver oils, used as a mordant for certain s^'uthetic fibres. Literature Cited Brown, James Templeman 1887 The whalemen, vessels and boats, apparatus, and methods of the fishery. U. S. Comm. of Fish and Fisheries, Fisheries and Fishery Industries of the United States, Sec. V, vol. 2, pp. 218-293. Jordan, David S. 1887a The Fisheries of the Pacific Coast. U. S. Comm. of Fish and Fisheries. Fisheries and Fishery Industries of the United States. Sec. II, pp. 589-629. 1887b Coast of California. In: The Whale Fishery. 1. History and present condition of the fishery. U. S. Comm. of Fish and Fisheries, Fisheries and Fishery Industries of the United States, Sec. V, vol. 2, pp. 51-61. BREEDING SEASON AND PRODUCTIVITY IN THE INTERSTATE DEER HERD^ By John E. Chattin Bureau of Game Conservation California Division of Fish and Game Deer herd productivity and breeding seasons are important factors in any program relating to deer management. The study of embrj^os fur- nishes an important source of information for determination of breeding potential and breeding dates of a deer herd. Studies currently in progress on the Interstate Deer Herd have afforded an opportunity to gather data bearing on this subject. The Rocky ]\Iountain IMule Deer herd occupying a summer range on the Fremont National Forest in southeastern Oregon and wintering in an area south of Clear Lake in Modoc County in northeastern California, has been termed the Interstate Deer Herd in recent studies. (Fischer, et al., 1944; Fischer, et al., 1945; Interstate Deer Herd Committee, 1946; Interstate Deer Herd Committee, 1947.) Studies to determine the number of deer in this herd indicate that an irruptive peak was reached in 1936 and the population remained high (18.000) until 1945-1946, when a drop in numbers to 13,600 was recorded. (Fischer, et al., 1944; Leopold et al., 1947 ; Interstate Deer Herd Committee, 1947.) Census figures taken dur- ing the 1946-1947 season on the winter range indicate the present popu- lation to be about 12,400. (Interstate Deer Herd Committee, 1947.) Other pertinent figures on herd composition are shown in Table I and Table II. TABLE I Percentage Composition of Herd * Winter census Calculated population Bucks Does T7„.„„= Number ^'''"^ classified Average 1937-1942 14,000 18,000 18,000 10.0 8.6 8.0 6.4 9.0 53.0 63.2 55.0 60.4 57.0 37.0 28.2 37.0 33.2 34.0 5,500+ 1943-1944... 5,986 1944-1945- 3,007 1945-1946 1946-1947 13.600 12,400 1,698 1,603 ' From Interstate Deer Herd Committee, 1946, 1947. TABLE II Buck-Doe and Doe-Fawn Ratios by Census Years Year ■ Buck- Doe ratio Doe- Fawn ratio Number of deer classified 1937-38 . -- 5.6 3.5 4.9 7.4 6.6 9.5 6.2 1 0.81 1.25 1.03 0.45 0.67 0.54 0.60 1,262 1938-39 2,882 1939-40 1,338 1943-44 5,986 1944-45 - 3,007 1945-46 1,696 1946-47 1,603 * From Interstate Deer Herd Committee, 1946, 1947. 1 Submitted for publication September, 1947. (25) 26 CALIFORNIA FISH AND GAME Significant facts revealed by comparison of these tables are (1) that a high herd population existed in 1943-44 and 1944-45 following the high doe-fawn ratio recorded for the two previous winter census years, and (2) that the last two years (1945-46 and 1946-47) indicate a drop in herd size correlated with low fawn sur\aval rates for the two previous years. Observations on breeding potential to be presented indicate that low faAvn survival and not reduced breeding potential is the effective factor in over-all productivity in the Interstate Deer Herd. Census figures of other deer herds may be cited for comparison with the Interstate Deer Herd, as presented in Table III. The significant figure in Table III is the 1 :6.2 buck-doe ratio in the Interstate Deer Herd. Data presented in this paper indicate that this relatively low ratio of bucks does not constitute a critical factor as regards herd productivity. Miscellaneous TABLE III Census of Deer H erd Composition * Herd or area Year Number deer classified Buck- Doe ratio Doe- Fawn ratio Glass Mountain, Modoc Co., California Glass Mountain, Modoc Co., California ... 1944-45 1945^6 1946-47 1936^5 1939-43 1946-47 432 587 437 12,137 2,529 1,603 1:3.8 1:3.9 1:4.0 1:3.0 1:2.9 1:6.2 1:0.71 1:0.65 Glass Mountain, Modoc Co., California 1:0.60 Fremont Forest, Oregon 1:0.63 Fish Lake, Utahf Interstate Herd .... 1:0.69 1:0.60 * Interstate Deer Herd Committee, t Robinette and Olsen, 1944. 1947. The collection of deer from the Interstate Deer Herd for critical study of food habits and parasite-disease incidence on their California winter range has furnished a source of data relating to the breeding potential, dates of breeding, and sex ratio of fawns. This study was initiated during the winter of 1945-46 and 14 deer (2 males, 12 females) were taken. During the winter of 1946-47 the study was continued and permit was granted to collect 60 female deer. Beginning in November, 1946, 10 deer were taken each month (five at the first of each month, and five at the fifteenth of each month). Collection was continued in this pattern through the fifteenth of April, 1947, following which time the seasonal spring migration to the summer range in Oregon was largely completed. Two deer killed accidentally by automobiles were also exam- ined and these records have been used to supplement the data here presented. Breeding Dates Recent studies by Cheatum and Morton (1946) on white-tailed deer in New York State, establishing a growth curve for deer embryos based on a series of specimens of definitely known ages, make possible the age determination of embryos from which breeding dates may be readily calculated. This established curve was assumed to be equally applicable to mule deer and was applied to Eocky Mountain mule deer (Odocoileus h. hemionus) embryos taken at autopsy from 43 female deer from the Interstate Deer Herd, January through April, 1947. Only those embryos DEER PRODUCTIVITY 27 -Wlo CD -ifio ■10% i% TofaJ -M3deer. Z-/-/; /8,2/ 2ZZS 2i-2? 30-3 4-7 g-// it-iS iL-i'i Decern her ZoZ3 It -27 U-31 /-V Figure 8. Seasonal distribution of breeding, based on embryo development. (Data grouped by four-day periods.) calculated to be over 50 days of age were used since accurate criteria for aging younger embryos were not available. Results of these calculations are presented in Figure 8. Examination of data indicates that 88 (88 percent) does were bred during a 22-day period (November 15th-Decem- ber 6th). The remaining five deer (12 percent) were calculated to have been bred within a 17-day period (December 18th-January 3d). Appar- ently none of the does was bred during the 11-day interval (December 7th-17th) following the primary breeding period. This hiatus would seem to indicate the occurrence of breeding on the part of some does during some recurrent period of estrus subsequent to the initial peak of breeding of the bulk of the deer herd, although no histological examination of ovar- ian tissue was made to substantiate this view. In addition to forehead-rump measure- ments of embryos for determining age, hind foot measurements were also recorded. Once the age had been arrived at by using forehead- rump measurements the determined age in daj'S was replotted in terms of hind foot length. Since hind foot length of embryos is a simple and easy measurement to take (Fig. 9), its use is suggested as being a valuable criterion for age determination of embryos by field person- nel. Figure 10 presents the pertinent data relative to use of hind foot length of embryos Figure 9. for age determination. Diagram of hind leg showing how meas- urement of the hind foot is taken ; A = measurement of hind foot. 28 CALIFORNIA FISH ANTD GAME 5 V <0 s ^ .t / y * / / / / / t • / 0 / f 1 f / .5 tj / 1 .5 / / ^ ~^ ,'' / 0 2. S £ 0 7i IC 0 iz 5 15 ■0 j-j S £listimQ. tec/ A^ e in D