Volume 36 Number 4 April1974 „r* c 1:. ^ -vV'^ •^'■/irEs o^ Marine Fisheries REVIEW National Oceanic and Atmospheric Administration • National Marine Fisheries Service SPECIAL NUMBER THE CAUFORNIA GRAY WHALE Marine Fisheries Review Vol.36, No. 4 April 1974 CONTENTS Articles 1 Preface. W. E. Evans 2 Introductory Remarks. Brian J. Rothschild 3 Respiration and Metabolism in Two Baleen Whale Calves, Eric A. Wahren- brock. Gary F. Maruschak. Robert Eisner, and David W. Kenney 9 Ballistocardiography as a Technique for Comparative Physiology. N. Ty Smith and Eric A. Wahrenbrock 15 Investigation of Blubber Thickness in a Gray Whale Using Ultrasonography. Michael P. Curran and William M. Asher 20 Surgical Attachment of a Telemetry Device to the Dorsal Ridge of a Yearling California Gray Whale. Eschiichtius lubiisiiis. John C. Sweeney and Joel L. Mattsson 22 Some Hematologic Observations on the California Gray Whale. Alfred Zettner 24 Some Coagulation Factors in Plasma from a California Gray Whale. Em hrii hiiiis nihii.\tii\. W. Medway 25 Fluorescent Karyotype of the California Gray Whale, Deborah A. Duffield 28 Some Physiological Parameters of the Blood of the California Gray Whale, William G. Gilmartin. Richard W. Pierce, and George A. Antonelis. Jr. 31 Feeding of a Captive Gray Whale, G. Carleton Ray and William E. Schevill 38 Sounds Produced by the Gray Whale. Eschiichtius nihiisiiis. James F. Fish. James L. Sumich. and George L. Lingle 45 Aerial Observations of Migrating Gray Whales, Esclirichiitis rohiisiiis. off Southern California, 1969-72, J. S. Leatherwood 50 A Note on Gray Whale Behavioral Interactions with Other Marine Mam- mals. J. S. Leatherwood 51 Aerial Observations of Gray Whales During 197.^. Paul N. Sund and John L. O'Connor 52 Telemetering of Temperature and Depth Data from a Free Ranging Year- ling California Gray Whale, Eschrichiiiis rohtisms. W. E. Evans 58 Capture and Harnessing of Young California Gray Whales. Eschrichiiiis rohiisiKs. Kenneth S. Norris and Roger L. Gentry Cover. — Alter almosi a year in capllvlly, the Calilornia gray whale. Gigi II, Is carried in a special cradle aboard ship to the site where she will later be released. Photograph, courtesy of Audio Visual Prod. Div., Naval Undersea Center, San Diego. Calif. U.S. DEPARTMENT OF COMMERCE Frederick B. Dent, Secretary NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION Robert M. White, Administrator National Marine Fisheries Service Robert W. Schoning, Director Address correspondence to: Marine Fisheries Review, NMFS Scientific Publications Staff, Room 450, 1107 N.E. 45th St., Seattle, WA 98105. Publication of material from sources outside the Service is not an endorse- ment. The Service is not responsible for the accuracy of facts, views, or opinions of these sources. Although the contents have not been copyrighted and may be reprinted freely, reference to source is appreciated. The Secretary of Commerce has de- termined that the publication of this periodical is necessary in the trans- action of public business required by law of this Department. Use of funds for printing this periodical has been approved by the Director, Office of Management and Budget, May 10, 1973. Editor; Thomas A. Manar Managing Editor; Willis L. Hobart For sale by the Superintendent of Documents, U.S. Government Print- ing Office, Washington, DC 20402. Price $1.25 (single copy). Subscrip- tion price; $12.50 a year, $15.75 a year for foreign mailing. Marine Fisheries Review Vol.36, No. 4 April 1974 CONTENTS Articles 1 Preface. W. E. Evans 2 Introductory Remarks. Brian J. Rothschild 3 Respiration and Metabolism in Two Baleen Whale Calves, Eric A. Wahren- brock. Gary F. Maruschak. Robert Eisner, and David W. Kenney 9 Ballistocardiography as a Technique for Comparative Physiology. N. Ty Smith and Eric A. Wahrenbrock 15 Investigation of Blubber Thickness in a Gray Whale Using Utrasonography, Michael P. Curran and William M. Asher 20 Surgical Attachment of a Telemetry Device to the Dorsal Ridge of a Yearling California Gray Whale. Eschiichliiis rohustus. John C. Sweeney and Joel L, Mattsson 22 Some Hematologic Observations on the California Gray Whale. Alfred Zettner 24 Some Coagulation Factors in Plasma from a California Gray Whale. Escliricli litis rohiisnis, W. Medway 25 Fluorescent Karyotype of the California Gray Whale. Deborah A. DufHeld 28 Some Physiological Parameters of the Blood of the California Gray Whale. William G. Gilmartin. Richard W. Pierce, and George A. Antonelis. Jr. 31 Feeding of a Captive Gray Whale. G. Carleton Ray and William E. Schevill 38 Sounds Produced by the Gray Whale. Eschrichtiiis rohiislus, James F. Fish. James L. Sumich. and George L. Lingle 45 Aerial Observations of Migrating Gray Whales, Esclirichtius rahiisius. off .Southern California, 1969-72, J. S. Leatherwood 50 A Note on Gray Whale Behavioral Interactions with Other Marine Mam- mals, J. S. Leatherwood 51 Aerial Observations of Gray Whales During 1973. Paul N. Sund and John L. O'Connor 52 Telemetering of Temperature and Depth Data from a Free Ranging Year- ling California Gray Whale. Escliriclilius rohusnis, W. E. Evans 58 Capture and Harnessing of Young California Gray Whales, E\i.hiii.litiiis nihusiiis. Kenneth S. Norris and Roger L. Gentry Cover. — Alter almost a year in captivity, ttie Caiitornia gray whale. Gigi II. is carried in a special cradle aboard ship to the site where she will later be released. Photograph, courtesy of Audio Visual Prod. Div., Naval Undersea Center, San Olego, Calif, U.S. DEPARTMENT OF COMMERCE Fretlerick B. Dent, Secretary NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION Robert M. White, Administrator National Marine Fisheries Service Robert W. Schoning, Director ,„o»;w^,. Address correspondence to: Marine Fisheries Review, NMFS Scientific Publications Staff, Room 450, 1107 N.E. 45th St., Seattle, WA 98105. Publication of material from sources outside the Service is not an endorse- ment. The Service is not responsible for the accuracy of facts, views, or opinions of these sources. Although the contents have not been copyrighted and may be reprinted freely, reference to source is appreciated. The Secretary of Commerce has de- termined that the publication of this periodical is necessary in the trans- action of public business required by law of this Department. Use of funds for printing this periodical has been approved by the Director, Office of Management and Budget, May 10, 1973. Editor: Thomas A, Manar Managing Editor: Willis L. Hobart For sale by the Superintendent of Documents, U.S. Government Print- ing Office, Washington, DC 20402. Price $1.25 (single copy). Subscrip- tion price: $12,50 a year, $15.75 a year for foreign mailing. ■'Ol-f, MASS. :-f. 0. 1. fflS = -0 = -i3 5 -D : CD i CD i □ The California Gray Whale Papers presented at the California Gray Wtiale Workshop, University of California, San Diego, Scripps Institution of Oceanography, 21-22 August 1972. Sponsored by Southwest Fisheries Center, La Jolla Laboratory, National Marine Fisheries Service, NOAA and U.S. Department of the Navy's Naval Undersea Center, San Diego. ^ o o % .1930 '•P CARL L. HUBBS, Chairman. W. E. EVANS, Editor. PREFACE In early March 1971 an expedition sponsored by Sea World. Inc. of .San Diego, under the direction of David W. Kenney with scientific support from the University of California. San Diego, captured a newborn female California gray whale [Eschrichiius ri>hu.'itns) in Scammon's Lagoon. Baja California Sur. Mexico. This whale, 5.84 meters long and weighing 1.952 kilograms, arrived at Sea World in San Diego on 17 March 1971. Although not the first successful capture of an immature California gray whale, this was however the be- ginning of a successful year of mainte- nance in captivity and the subsequent release into the wild, the first time for any species of baleen whale. The results of the scientific studies con- ducted during this year of captivity and the later field observations which were stimulated by the release of this unique whale, are the subject of this publication. Many important contributors to our overall understanding of the com- plexities of the biology of the Cali- fornia gray whale are not formally represented in this report as contribu- tors. The impact of the work of Carl L. Hubbs. Scripps Institution of Oceanography. University of Califor- nia, San Diego, La Jolla; Raymond Gilmore, Museum of Natural History, San Diego; and Dale Rice, National Marine Fisheries Service. Northwest 1 Fisheries Center. Seattle. Wash., as pioneers in estabUshing the basis for our present knowledge of the status of the gray whale population cannot be overstated. Special acknowledgement is also due David W. Kenney. of Poway, Calif, for his efforts in successfully capturing and maintaining in good health the immature gray whale named Gig! II. the subject of most of the research reported here. Dr. Kenney should be applauded for his persistence in overcoming seemingly insurmountable opposition. Many of Dr. Kenney 's colleagues were doubt- ful that a newly born gray whale could be successfully maintained alive in captivity for more than a few months, let alone one year. Yet, this INTRODUCTORY REMARKS BRIAN J. ROTHSCHILD It is a great pleasure to welcome you to the California Gray Whale Workshop. The Workshop is being held in a significant location and at a particularly appropriate time. The location. La Jolla. is of course, quite near the area surveyed as part of the well-known California gray whale census and is also a focal region for other studies on the dynamics and life history of the California gray whale. Some of this research will be presented at this Workshop where you will hear about such diverse topics as husbandry, respiration and metabolism, cardiovascular physiology and blood studies and behavior and physiology — all related to the California gray whale. In addition to being a region where many contemporary studies on the gray whale have been undertaken, it was also in this general area of the North American coast that Charles M. Scammon. whaler and sometime Brian J. Rothschild is Director, Southwest Fisheries Center, Na- tional Marine Fisheries Service, NOAA, La Jolla, CA 92037. goal was achieved with overwhelming success. From predictions of normal growth. Gigi should have reached a total weight of 5.946 kilograms and a length of 8.30 meters by 20 March 1972. During her last week in captiv- ity (6-13 March 1972). Gigi II was weighed three or four times. Due to the use of three different scales and two different conditions of weigh- ing (i.e., animal fasting and animal fed prior to weighing), her final weights ranged from 5,364 kg to 6,350 kg. This weight range remark- ably brackets the predicted weight previously mentioned. Her final over- all length on 13 March 1972 was 8.15 meters, also significantly close to the predicted length of 8.30 meters based on normal growth. W.E.E. captain in the U.S. Revenue Marine, undertook his early studies of the natural history of the gray whale. His studies "The Marine Mammals of the North-Western Coast of North Amer- ica." were published in 1874. Many of Captain Scammon's observations on the gray whale were made in the mid-1850's when he discovered a major nursery ground of the Califor- nia gray whale in a Baja California embayment. Laguna Ojo de Liebre. now frequently called Scammon's La- goon. Scammon was also involved in (he early, intensive harvest of this species, an activity that was terminat- ed in 1946 when the International Whaling Commission declared the gray whale a protected species. The timing of this symposium is also appropriate. There is now an unprecedented interest in marine mam- mals. TV. radio, motion pictures, newspapers and magazines have all contributed to a growing public aware- ness and concern with these fascinat- ing animals. Unfortunately, this de- luge of publicity has resulted in a mixture of fact and fiction. The tic- tion has been further fed b\ various indiscriminate interpretations which often accompany events of high pub- licity value, inadequate data collec- tion, and difficulties in interpreting the sparse marine mammal data. Fur- ther complications arise from conflict- ing and contradictory views of special interest groups that influence resource decisions. A case in point is. of course, the blue whale. Because this is also a time when significant policy and conservation decisions are being made on marine mammals, it is particularly important to concentrate on the generation of factual information. The conservation of our resources is essentially a deci- sion-making process; this process can only be effective if decision-makers are supplied with appropriate facts. Workshops such as this California Gray Whale Workshop will do much to contribute to our understanding and knowledge of marine mammals and assist in making better resource decisions which hopefully will preserve these Leviathans for the education and enjoyment of future generations. I think Herman Melville had a premonition that all of this would come to pass; that status of marine mammal stocks would be of world concern and as a small part of this concern we would be holding our workshop. In fact he could be before you now saying, as he did in Mohy Dick: "Already we are boldly launched upon the deep; but soon we shall be lost in its unshored, harborless immensities. Ere that come to pass; ere the Pequod's weedy hull rolls side by side with the barnacled hulls of the Leviathan; at the outset it is but well to attend to a matter almost indispensable to a thorough appreciative understanding of the more special leviathanic revela- tions and allusions of all sorts which are to follow. It is some systematized exhibi- tion of the whale in his broad genera, that I would now fain put before you. Yet is it no easy task. The classification of the constitu- ents of a chaos, nothing less is here essayed. Listen to what the best and latest authorities have laid down . . ." MFR PAPER 1045 Respiration and Metabolism in Two Baleen Whale Calves F.RIC A. WAHRENBROCK, GARY F. MARUSCHAK, ROBERT ELSNER, and DAVID W. KENNEY ABSTRACT Eric A. Wahrenbrock and Gary F. Maruschak are members of the staff of the Anesthesia Labo- ratory of the School of Medicine, University of California, San Diego. La Jolla, CA 92037. Robert Eisner is a member of the staff of the Physiological Research Laboratory of Scripps Institution of Oceanography. L'niversitv of California. San Diego, P^O. Box 109. La Jolla, CA 92037. David W. Kenney was formerly a member of the staff of Sea World. Inc.. San Diego. Calif.; his present address is 14220 Poway Rd.. Poway, CA 92064. W-V perfonucd rcspiiiilnry unci mcuiholic sliulics on two female gray whale calves. Allhongh one died 2 inonlhs after capture, the other thrived during a year'.f captivity, pennitting serial observations while growing, and weiglied in e.Kcess of 6.350 kg when released. They appeared to he of normal size and weight compared to whtdes in the wild. Relative increases in body length and weight, lung volume, minute ventilation, and metabolic rale were similar to those in terrestrial mammals, as was the growth efficiency. Lung volume and metabolic rate could be predicted with only partial success from the relation- ships of those variables to body weight proposed by Tenney and Kleiber, per- haps due to intniuturity in the whales. Compared to terrestrial mammals, tite ratio of tidal volume to resting lung volume in the wliule was large, while the ratio of wasted ventilation to tidal volume was small. We measured respiratory excursions of arterial Oi and CO2 tensions of 36 and 16 mm Hg, respectively, consonant with the relationships between respiratory rate, lung volume, tidal volume, and metabolic rate. INTRODUCTION Although the physiology of toothed whales. particularU porpoises, has been studied at some length (Irving. Scholander, and Grinnell. 1941: Olsen. Eisner. Hale, and Kenney, 1969; Olsen. Hale, and Eisner. 1969; Scho- lander. 1940), the study of living baleen whales has been particularly elusive. The size and dietary habits of these large mammals present for- midable obstacles to their maintenance in captivity, and these obstacles are compounded by ignorance of the whales' growth rate, dietary require- ments, metabolism, and hematologic and cardiorespiratory physiology. However, these and other aspects of the biology of baleen whales are, in many respects, unique among mam- mals: research would therefore be doubly rewarding. This line of rea- soning led to the capture and study of the two animals reported herein, and to this workshop. We were naturally inclined toward studies of especial personal interest, and recognize their limited scope and serious omissions (cardiac out- put, for example). We are here re- porting observations on growth, res- piratory function, and metabolic rate: additional reports of detailed nutritional, metabolic, biochemical and hemotologic studies; inert and anesthetic gas uptake; and respira- tory mechanics will follow. METHODS The first gray whale calf (Gigi 1) was captured in Scammon's Lagoon, Baja California, Mexico in February 1965 and brought to San Diego, where a number of respiratory and metabolic studies were performed. Although the whale at first seemed to thrive, it died of an uncontrollable infection about 2 months after it was captured. The second calf. Gigi II, was cap- tured in March 1971, again in Scam- mon's Lagoon, and was again kept in (increasingly larger) pools at an oceanarium in San Diego. Gigi 11 thrived indeed: gained in size, was weaned, was studied intensively, and was reluctantly (but inevitably) re- leased almost exactly a year after her capture. Two of the authors were members of each of the expeditions (DWK. and RE on the first, and DWK and EAW on the second) and one of us (DWK) was responsible for the medical care of both animals while in captivity. For most of the studies reported here, the water level in the tank was lowered so as to nearly immobilize the whale, leaving about 12 inches of dorsal body surface above the wa- ter level, and the blowhole barely awash. A few of the studies were per- formed with the whale completely stranded on the bottom of the empty tank. The respiratory pattern in whales and other marine mammals consists of an expiration followed by an im- mediate inspiration, followed by an interrespiratory pause during which the airway is closed. The duration of the pause in Gigi 11 was ahout I minute, and inspiration and expiration together required about 2 seconds. Two observations can be made from this respiratory pattern (commonly called ■■apncustic'"): I) a valve would be needed in order to separate inspira- tion from expiration, and 2) resting lung volume is different from that in terrestrial mammals, because in ceta- ceans it includes the tidal volume. Accordingly, we fabricated nonrc- breathing valves: first of approximate- ly 5 inches diameter, and later (for Gigi ID of 8 inch stovepipe (Figure I), thus permitting us to collect un- contaminated exhaled gas. For Gigi 1 a large, calibrated, counterbalanced, bellows-tvpe spirometer was used: and for Gigi 11. expired gas was collected in 900 liter meteorological balloons. The volume of exhaled gas was then measured by emptying the balloons through a calibrated dry gas meter (Wright Respirometer or American Meter Co.)' at a constant, known flowrate. Aliquots of mixed expired gas from Gigi I were analyzed for Og and CO2 with a .Scholander apparatus, and for Gigi II with a moditied Hal- dane apparatus (Lloyd-Gallenkamp). as were samples of end-tidal gas, ob- tained from a port just beyond the expiratory valve leaflet of the nonre- breathing device. Resting lung volume was measured in Gigi II by injecting 1.50 liters of pure helium into the inspiratory port of the nonrebreathing valve during inspiration. The subsequent expira- tion was captured, and mixed expired gas analyzed for helium with a sensi- tive, calibrated katharometer (W. F. Collins). Arterial blood was drawn Irom Gigi II bs percutaneous puncture of the digital artery in a flipper with an 18 gauge 3 inch needle, and arterial placement ensured by observing pul- sations of blood through the needle. Because of the configuration of the ' Reference to name of firm does not imply endorsement by tfie National Marine Fisheries Services, NCAA arterial and \enular system, it is pos- sible that arterial blood was contam- inated at times with venous blood. Some of the gas samples from Gigi 11. and all of her blood samples, were analyzed for O2 and CO., tensions (/'02 and ^002' w''h a hlood gas analyzer (Radiometer BMS-3). with which blood pH could also be deter- mined. From timed gas collections during which the number of breaths was also counted, respiratory rate, minute ventilation, tidal volume, oxygen con- sumption, and wasted ventilation (or •dead space" fraction. ^jIV,) could thus be determined by suitable analysis. RESULTS In the first few weeks of captivity, each whale lost weight, but gained thereafter (Figure 2). The rate of gain during the first 8 months was about 200 kg/mo in Gigi II.2 She was weaned at about 7 months of age. as are calves in the wild (Rice and Wol- man. 1971). At age 10 months, she entered a very rapid growth phase during which her food intake increased from about 1.200 to about 1.800 pounds of squid/day. and her rate of gain in weight increased almost 5 fold, to 970 kg/mo or (for those of us who enjoy such reductions) approx- imately -3 pounds/hour. Each whale gained in length regularly: although Gigi 1 was smaller than Gigi II when captured, their increases in body size were similar (Figure .^). This suggests that the infection did not seriously impede her growth. Respiratory rate (/) was counted on manv occasions; it varied with the whales' activity. It averaged 2/niin for Gigi 1 at first, and increased to 4 or .s/min after age 2 months. However, this whale had atelectasis and pneu- monia secondary to a harpoon wound. 2 Both calves were first fed by gavage. and in botti trie liquid diet was gradually changed from mainly whipping cream to a mixture of ground squid, ground bonita, calcium casemate, yeast, and corn oil For Gigi-ll. the proportion of squid in the diet was gradually increased until the lime of weaning Figure 1. — NonbreathJng valve tor Gigi II, constructed of 8 inch stovepipe and containing one quarter inch neoprene foam rubber valve leaflets. Inspiration was from the side-arm, and the inspiratory valve leaf and its supporting ring were slanted so that closure was assisted by gravity. AGE SIZE Figure 2. — The whale was weighed with an industrial heavy duly scale (Dynamometer) by lifting her from the water with a crane while supported on a canvas and pipe slrelcher, and subtracting the tare weight. Body length was measured on a straight line from lips to no4ch in fluke. Dala from Gigi I are represented by open circtes and squares, and tor Gigi ft by solid symbols. Length in meters on left hand scale; weight in thousands of kilograms on right hand scale. leaving the ineamng of this observa- tion somewhat uncertain. When Gigi II was motionless, or nearly so, /' averaged 1/min, irrespective of age. Accordingly, tidal volume ( F,) and minute ventilation were nearly equal (Figures 4, 5). Each value for F, is an average of three or more measure- ments, as we observed that \\ varied 7 6 WEIGHT LENGTH / 1-:: 5 / 4 '■5 , / 3 2 ^^^ 1- METERS Figure 3. — Weight plotted as a (unction of length in the two gray whale calves. Data from Gigi I is represented by squares, and from Gigi II by circles. At the time of the rapid weight increase Gigi II was approxi- mately 9.5 months old. Gil more (1961) reported data from one calf which died after being stranded in San Francisco Bay. Data from Rice and Wolman (1971) represent north and southbound calves (lower and upper points respectively): the difference supports the hypothe- sis that gray whales fast during the southern migration. LUNG VOLUME . 400 / IITE»S / 300- / • / 200 / /• 100 • WEIGHT kg X 10^ -[ 200 - TIDAL VOLUME / 150- / - LITERS / 100- 50- ••/ WEIGHT 1 \ 1 1— kg X 10' 1 1 1 Figure 4. — Tidal volume (V|) in a gray whale calf during the first year of life. Tlie regression equation for tlie line is: V( = (47 ^ body weigtit in metric Ions) - 70. Tlie correlation coefficient r = 0.99. MINUTE VENTILATION I 4- LITERS markedly from one breath to the next, sometimes by 50 percent. Resting lung volume. (Figure 6) necessarily varied from breath to breath also, and in addition, the mea- surement was technically difficult be- cause of the difference between in- spired and expired \\. Nevertheless, five measurements were felt to be adequate. Two measurements were made at weight = 6.150 kg. one when awash and one when stranded on the bottom of the completely drained tank. Lung volume was re- duced by about 20 percent by strand- ing, although that value was deter- mined only once. From time collections of mixed ex- pired gas. oxygen consumption was computed (Figure 7). The composi- tion of end tidal gas from Gigi I! was determined on several occasions, and did not vary systematically with age. End tidal ^02 varied from 54 Figure 5. — Minute ventilation (Vf) in two gray wtiale calves, expressed as a function of body weigfil. Ttie triangle represents data from observations in Gigi I. Ttie regression equation for Itie data from Gigi II (circles) is: V£ = (70 X body weight in metric tons) - 117. Although the r = 0.94 for this rectilinear regression, it is apparent that a sigmoid curve could be even more closely filled to the data. Figure 6. — Resting lung volume in a gray whale calf (Gigi II), expressed as a function of body weight. Resting lung volume includes tidal volume, and is the volume of gas in the lungs during the intervals between breaths. The equation for the line is: lung volume = (70 X body weight in metric tons) - 44; for which r = 0.94. Table 1. — Arterial blood gas tensions and pH, drawn at random during the respiratory cycle. Age, months 2 5 3 0 10 55 62 60 56 69 41 7 23 7,32 7 35 Pa02, mm Hg PaC02, mm Hg pH OXYGEN CONSUMPTION WEIGHT kg X 10^ WEIGHT kg X lO' H 1 1 H 3 4 5 6 Figure 7, — Oxygen consumption in liters/min (Vq.,) in two gray whale calves, expressed as a function of body weight. The triangle rep- resents data from observations in Gigi I. The regression equation tor the data from Gigi II (circles) is: VOj = (41 « body weight in metric tons) - 5.7; lor which r = 0.96. 70 -Po,= 3 6 lorr 60- . ^ '^ Pco, = 16 torr 50- ^ ^^^ 40- ^^^ ' 30- . Po CO2 20- 10- ■ Poo, 1 1 1 Figure 8. — Arterial O2 and Cq., tensions (Pao^ and PacOj) '" ^ 9"* wtiale cal'f, from se- quential blood samples drawn about every 15 sees during five respira- tory cycles. so 60 70 to 85 mm Hg, and the corresponding Pcoo varied from 75 to 54 mm Hg. We computed wasted ventilation from the difference between end tidal and mixed expired Pco2- " equalled '3.0 percent of V^ at age 3 months and 13.5 percent at age 13 months. Arterial Po2' ^C02- ^^^ P^* ^'^■'^ measured on three occasions in sam- ples drawn at random during the res- piratory cycle. (Table I). Those values also varied considerably: the differ- ences between arterial and alveolar Pq„ and Pcoo ^^"^^ difficult to inter- pret, and were sometimes negative. Therefore, we measured blood gases and pH in arterial blood drawn se- quentially during the respiratory cy- cle (about every 15 sec); the values then varied systematically (Figure 8). DISCUSSION As we are presenting data concern- ing the respiratory and metabolic changes in growing whales, we should examine the hypothesis that their size and rate of growth were normal. There is ample reason to raise the question, for confined animals fed contrived diets should always be sus- pected of exhibiting biological values which would be abnormal for the population in nature. There are two methods of examining this question: to make comparisons with other gray whales; and to look for internal evi- dence of abnormal growth and de- velopment. Data from Gilmore (1961) and Rice and Wolman (1971) comprise the first method, for they have exam- ined gray whale calves similar in age and size to Gigi II. Her weight and length at the time of release compare favorably to the other data on calves thought to be yearlings (Figure 3). As gray whales in the wild are thought to fast during the southern migration (Rice and Wolman, 1971), the obser- vation that Gigi II was slightly heavy for her length should be interpreted with caution. The internal evidence relating to the question consists of the observa- tion that Gigi II sustained an increase in body length which preceded any considerable growth in body weight, mitigating against an argument that she was grossly overweight or overfed, and which is consistent with the pat- tern of early growth in other mammals (i.e.. exponential for weight and linear for length) (Christian, 1972; Carlan- der and Ricker, 1962; Brody, 1964). Although there is some disagree- ment (Gilmore. 196 l.andpers. comm.). newborn gray whales are estimated to be 4.9 meters in length at birth (Rice and Wolman. 1971). Their birth- weight is less certain, although Rice proposes the weight of the products of conception at term to be between 1.000 and 2.000 kg. Our estimates of the birthweight of the two whales at about 1.500 kg. and the birthlength at just under 5 meters are therefore consistent, and permit extrapolation of their ages at capture to 4 weeks for Gigi I and 10 weeks for Gigi II. At age 1 year. Gigi II had increased her birthweight by about 3.5 fold, and her birthlength by a little less than 1.5 fold. Comparison of growth rates be- tween species may be deceptive due to species differences in longevity, newborn maturity, and adult body size. However, since humans and gray whales (Rice and Wolman. 1971) have similar life spans, and are both large mammals, it is of interest to consider their relative growth rates in body weight, respiration, and me- tabolism. If mature female gray whales are 13 meters in length (Rice and Wol- man. 1971; Scammon. 1874). and 30 to 35 thousand kg in weight, then the newborn whale must increase its birthweight by about 20 fold and its birthlength by about 2.5 fold. The fractional annual and ultimate in- creases in weight of the whales are similar to those in man. but the frac- tional increase in length is greater (Benedict and Talbot. 1921). Lung volume in human infants in- creases as a cubic function of body length (Cook and Hamann. 1961). a satisfying observation considering the geometry involved. The regression onto body weight is not very reliable; the regression onto length is approxi- mately; Total Lung Capacity (liters) = body length (meters) cubed. Al- though we have insufficient data for the whale to make firm conclusions (and have arbitrarily linearized the data against body weight in Figure 6). calculation of resting lung volume against body length suggests that an equation of Lung Volume = 0.62 X length' also fits the data. This rela- tionship seems reasonable, as resting lung volume in the whale is probably less than total lung capacity. Tidal volume and minute ventila- tion increased during the year's growth, and as a first approximation, we have again linearized the data (Figures 4.5). We recognize that changes in res- piratory function and metabolic rate are probably not rectilinear functions of body weight, but we also recognize that the data available to us represent only a small portion of the full curves. Tidal volume increased about 8 fold as body weight tripled: the correspond- ing value for minute ventilation was 10 or 12 fold. Comparison of this growth rate with that of terrestrial mammals is awkward, because of marked changes in their respiratory rate during growth (Watson and Low- rey. 1962). while respiratory rate in the whale was constant. In terrestrial mammals, tidal volume changes as a function of lung volume (which in turn varies as a cubic function of length), while minute ventilation changes as a function of metabolic rate (Tenney and Kemmers. 1963); a more complex function of growth, which is not linear on any conve- nient parameter of body size because of growth spurts during early and late childhood (Benedict and Talbot. 1921). The increase in the metabolic rate of Gigi II corresponded to the in- crease in her ventilation, and for a tripling of weight, increased about 10 fold. This increase is of the same order as the increase in human metabolic rate during the first year (about 8 fold) (Benedict and Talbot. 1921). and is consistent with our general impression that growth in the whale, whether of body weight, lung volume, or metabolic rate, proceeded in paral- lel with, or only slightly more rapidly than, human growth. Observation of animals at the ex- tremes of body size invites inter- species comparisons of biological phenomena. The existing data for two such correlations; of lung volume with body size (Tenne\ and Remmers. 1963), and of metabolic rate with body size (Kleiber. 1961), are par- ticularly well organized. Tenney has shown that lung volume is closely related to body mass (over a range of body mass of 5 orders of magni- tude) by the equation: log lung vol = 1.02 log body weight — 1.25, with volume in liters and weight in kg. This yields a predicted lung volume in Gigi II of 410 liters at 6,150 kg, which corresponds closely to our measurement of 428 liters, but which diverges widely from values obtained early in her growth. Tenney measured total lung capacity (TLC) of excised lungs, and we measured resting lung volume: this ordinarily considerable difference is fortuitously minimized by the fact that resting lung volume in the whale is a larger fraction of TLC than is the case for terrestrial mammals. This measurement permits considerable extension of Tenney's data, for his largest animal, also a cetacean, weighed only 1,750 kg. Kleiber studied the metabolic rates of animals also differing in body size by about 5 orders of magnitude, and concluded that metabolic rate was best related to the 0.75 power of weight, by the equation: log A/ = 1.83 + (0.756 log W) ±0.05, with M in kcal/day and W in kg. Using the con- version factor of 4.8 kcal = 1 liter of O), the whales" metabolic rates compare favorably with that regres- sion line up to a body weight of 3,000 kg. but diverge significantly there- after. The last metabolic rate mea- sured was 16.8 l/min. while the cal- culated value from Kleiber's equation is 6.8 l/min. It is notable that metab- olism in Gigi II. Benedicts elephant, and Irving's whale all differ from Kleiber's prediction, thereby raising the question of whether large mam- mals do indeed follow the 0.75 power rule. However, the value for the 70.000 kg fin whale was extrapolated from a measurement in a porpoise (Irving. Scholander. and Grinnell. 1941). and neither the elephant nor our whales were studied under condi- tions meeting Kleiber's criteria of ambient temperature neutrality, adult- hood, and basal postabsortive state. The resulting errors would be in the direction of the observed differences. Divergence from the 0.75 power rule may also be seen in growing cattle, horses, children, and rodents (Brody. 1964). During the phase of rapid weight gain. Gigi II ate from about 1.200 to about 1.800 pounds of squid per day, and gained weight at the rate of about 980 kg/mo. If we assume thai squid are about 80 percent water and the dry weight is equivalent to 5 kcal/gm (R. Lasker. pers. comm.). and make the further assumption that growing whale tissue contains the same energy (1.720 kcal/kg wet weight) as other growing mammalian tissue (Mayer. 1949), it is possible to calculate the gross efficiencies for growth of a baleen whale calf of 10.3 percent and 6.9 percent. Correcting for metabolic rates of 11.0 and 16.8 liters O'/min yields net efficiencies for growth of 12.0 percent and 8.0 per- cent (Brody. 1964). In general, growth efficiency is independent of body size (Kleiber. 1947), but is a diminishing function of metabolic age: the calculat- ed values are within the expected range for terrestrial mammals beyond the first doubling of body weight (Brody, 1964). Tidal volume equalled about 50 percent of resting lung volume, ir- respective of age or size. This is a smaller ratio than that reported for other diving mammals (Irving et al.. 1941; Olsen et al.. 1969; Scholander, 1940), although they were mature. The ratio of wasted ventilation to tidal volume (VjjVj) in Gigi II was about 13 percent, irrespective of age. This value is consistent with observa- tions in mature diving mammals (Ir- ving et al., 1941; Scholander. 1940. and Kooyman. pers. comm.). and is considerably smaller than the ratio in terrestrial mammals. However. I'j/ Vj diminishes with increasing I'^ in humans and dogs (Bouhys. 1964). a pertinent observation in view of the relatively large V^ in the divers. Fluctuations in arterial Pq and A:02 *''h respiration have been pre- dicted in man and terrestrial animals (Otis. 1964; Suwa and Bendizen. 1972) and diving animals (Irving et al.. 194 I). Those fluctuations are influenced by: 1) the relative sizes of the tidal and resting lung volumes; 2) the relation- ship between resting lung volume and metabolic rate; 3) the relationship between the fluctuating pulmonary blood flow and the fluctuating alveolar gas composition (Otis, 1964): and 4) the solubility of respiratory gases in pulmonary tissue. The greatest differ- ences we observed were A/'og = 36 mm Hg and A/coo ~ '^ "^^n Hg (Figure 8): These considerable excur- sions follow from the ratio of resting lung volume to tidal volume, which in the whale is about 2 and in man about 5; the ratio of resting lung volume to metabolic rate, which in the whale is about 20 and in man is about 10; and the very large differ- ence between human and whale res- piratory rates. Taken together, these relationships suggest that apneustic breathing in the whale is just as it seems: each breath interrupts a res- piratory pause which actually repre- sents a period of breathholding, dur- ing which appropriate changes occur in arterial blood gas tensions. Al- though tempting, approaches toward cardiac output computation are ham- pered by ignorance of the composition of mixed venous blood. Calculations of the "mean" alveolar gas or arterial blood composition are similarly ham- pered, and by imprecision in the sample collection timing as well. CONCLUSIONS 1. These two gray whale calves have provided the first opportunity for the collection of physiologic data from living baleen whales. The growth- rate in one of them was such that she became the world's largest captive animal. 2. Comparison of their size with that of whales in nature, and of their growthrate with one another and with other animals, strongly suggests that their size and growthrate were normal. 3. We observed increases in res- piratory function and metabolism during growth similar to the increases in terrestrial mammals. In particular: relative increases in body weight: and of lung volume, minute ventilation, and metabolic rate as functions of body weight, proceeded in approxi- mate parallel to the relative increases observed in man, 4. Interspecies comparisons of ab- solute lung volume and metabolic rate can also be based on body weight. Where the gray whale calves differed from correlations drawn between mam- mals including those at the extremes of body size, the departure could be explained by the whales' immaturity. 5. One of the whales entered a rapid growth phase, during which it gained approximately 1,000 kg/mo. Its gross efficiency for growth, cal- culated from the amount it ate and weighed, diminished from about 10 percent at a body weight of about 3,000 kg to about 7 percent at a body weight of 6,350 kg. 6. The relationships between tidal volume, resting lung volume, and wasted ventilation are similar in the gray whale calf to these in other div- ing mammals: although those rela- tionships are different from the ones in terrestrial animals, they follow from the apneustic respiratory pat- tern (of infrequent but very large breaths interrupting long periods of breathholding at high lung volume). 7. The apneustic pattern of breath- ing also results in respiratory excur- sions in arterial oxygen and carbon dioxide tensions much larger than those predicted in terrestrial mammals. ACKNOWLEDGMENTS Both whales were kept in pools at Sea World, Inc., an oceanarium in San Diego, Calif. The staff and ad- ministration extended to investiga- tors courtesies and facilities both large and small, ranging from hot showers and coffee to underwriting the expeditions and the subsequent upkeep of the whales: and thereby made these studies both possible and enjoyable. In particular. Bud Dona- hoo and Sue Bailey provided Gigi II and her investigators with under- standing and with expert assistance. We acknowledge with thanks the sup- port of Robert Peterson and the crew of the FiilcDii involved in the capture. transport, and maintenance of Gigi I. We are also grateful for the consider- able assistance of Jack Schultz, Ken Hamai, James Wright. Brian D' Aoust, and Morgan Wells. Finally, we are grateful to the two Gigis, for they, by patiently enduring our several insults, made possible observations new to the largest and least accessible sub- order of living mammals. LITERATURE CITED Benedict, F. G., and F. B. Talbot. 1921. Metabolism and growth from birth to puberty. Carnegie Inst. Wash., Publ. No. 302, Wash., D.C. Bouhvs, A. 1964. Respiratory dead space. In W. O. Fenn and H. Rahn (editors). Handbook of phvsiologv. Respiration, Sect. 3. Vol. 1, p. 699-714. Am. Physiol. Soc, Wash., D.C. Brody, S. 1964. Bioenergetics and growth. Hafner, New York. Carlander, K. D., and W. E. Ricker. 1962. Postnatal vertebrate development. In P. L. Altman and D. S. Dittmer (editors). Growth, p. 33.V378. Fed. Am. Soc. Exp. Biol., Wash., DC. Christian, I.. L., L. N. Hazel, J. P. Scott, M. Shelton, G. M. Sidwell. N. R. Ellis, W. W. Swett. G. S. Templeton. and G. Van Wagener. 1972. Growth: Mammals other than man. In P. L. Altman and D. S. Ditt- mer (editors). Biol, data book. p. 207-216. Fed. Am. Soc. Exp. Biol., Bethcsda. Md. Cook, C. D., and J. F. Hamann. 1961. Rela- tion of lung volumes to height in healthy persons between the ages of .S and 38 years. J. Ped. 59:710-714. Gilmore, R. M. 1961, The story of the gray whale. 2nd ed. Privately publ., San Diego, 16 p. Irving, L., P. F. Scholander, and S. W. Grin- nell. 1941. The respiration of the porpoise, Tiirsuip.'i irunciilii.s. J. Cell. Comp. Physiol. 17:14.5-168. Kleiber, M. 1947. Body size and metabolic rate. Physiol. Rev. 27:5 1 1-541. . 1961. The fire of life. An introduc- tion to animal energetics. John Wiley & Sons, Inc.. New York, 454 p. Mayer, J. 1949. Gross efficiency of growth of the rat as a simple mathematical func- tion of lime. Yale J. Biol. Med. 21:415-419. Olsen, C. R., R. Eisner, F. C. Hale, and D. W. Kenney. 1969. -Blow' of the pilot whale. Science 163:953-955. Olsen, C. R., F. C. Hale, and R. Eisner. 1969. Mechanics of venlilalion in the pilot whale. Resp. Physiol. 7:137-149. Otis, A. B. 1964. Quantitative relationships in steady-state gas exchange. In W. O. Fenn and H. Rahn (editors). Handbook of physiology. Respiration. Sect. 4, Vol, 1. p. '681-698. Am. Phvsiol. Soc, Wash., D.C. Rice, D. W., and A. A. Wolman. 1971. The life history and ecology of the gray whale (Eschruhiiiis robt4snis). Am. Soc. Mammal., 142 p. Scammon, C. M. 1874. The marine mammals of (he North-western coast of North America. John H. Carmany and Co., San Francisco, 319 p. Scholander, P. F. 1940. Experimental inves- tigation of the respiratory function in divid- ing mammals and birds. Hvairad. Skr. 22:1-131. 8 Suwa, K., and H. H. Bendixen. \912. Pul- monary gas exchange in a tidally ventilat- ed single alveolus model. J. Appl. Phvsiol. 32:834-841. Tenney, S. M., and J, E. Remmers. 1463. Comparative quantitative morphology of the mammalian lung: diffusion area. Nature 197:54-56. Watson, F.. H., and G. H. Lowrey. 1962. Growth and development of children. 4th ed.. Year Book Medical Publishers. Inc., Chicago, 384 p. MFR Paper 1045. From Marine Fisheries Review, Vol. 36, No. 4. April 1974. Copies of this paper. In limited numbers, are available from D83. Tec finical Information Division, Environmental Science Information Center. NCAA, Washington, DC 20235. MFR PAPER 1046 Ballistocardiography as a Technique for Comparative Physiology N. TY SMITH and ERIC A. WAHRENBROCK ABSTRACT The ultra low-frequency haUistocarttioi^rcini was recorded on a young Califor- nia gray whale. The tracing /.v remarkably similar to those obtained from man and mouse, both in amplitude and in form. The IJ amplitudes fr>r mouse, man. and whale were 2.6, 4,3, ami 4.6 cntlsec'-. We conclude that greater differences are caused by poor recording technique or by disease than by species differences. The major interspecies differences were seen in the timing of cardiac events, such as preejeclion or ejection time. These differences could be caused by differences in heart size. The ballistocardiograph (Beg) is a device for evaluating the mechanical function of the heart. It has been recorded in an incredible array of animals, ranging from egg embryos to cattle. One of the more interesting facts to arise from these recordings is that the tracings are remarkably similar among species, particularly mammals. This similarity holds both in form and in amplitude. It was therefore an excellent opportunity to N. Ty Smith is an Associate Professor of Anesthesia at the University of California at San Diego, Veterans Administration Hospital, San Diego, CA 92161, and Eric A. Wahrenbrock is an Assistant Professor of Anesthesia at the University of California, San Diego, extend these observations to Gigi, an animal with an entirely different mass and configuration from other mammals previously used. The Beg records the movements of the body caused by movements of blood in the body. First recorded in 1887. the Beg has undergone a series of ups and downs in its attempts to become a useful tool for measuring cardiovascular function noninvasively. Not until the 1950"s when physicists and engineers entered the held, did the Beg finally re-emerge as an accurate, relatively simple technique. Essentially, the Beg works on the principle that an attempted shift in the center of mass of a floating body is compensated for by a movement of the body in the opposite direction, so that the center of mass remains constant in relation to a fixed point. Thus, if blood moves in one direction after ejection by the left ventricle, the body will move in the opposite direction. These movements are quite small, but the reader has certainly noticed a slight bodily movement as he lies quietly on a bed or a slight movement of the pointer on a weighing scale, each movement synchronous with the heart beat. This minute body move- ment can be recorded as displace- ment, velocity, or acceleration. Figure 1 shows examples of normal tracings in man. The important fact to note is that the major components of the Beg occur during ejection of blood, particularly during the early portion. METHODS When the physical scientists entered the field, they laid down certain standards for recording the Beg, standards which were to convert bal- listocardiography from a haphazard technique to a precise one. The first requirement is that a very light bed is necessary, in contrast to the heavy ones formerly used. A ratio of 10:1 for subjectibed is minimal. Second, coupling, or binding, of subject to bed must be as tight as possible. Third. coupling to ground must be minimal, so that ambient vibrations can be attenuated. The Beg is an extremely sensitive instrument. Peak displace- ment is about \00iJ. peak acceleration, a few millig"s. g being the accelera- tion of gravity. With older instruments, vibrations from a truck outside the building were able to destroy a bal- Phono EKG Rl Hfort listocardiographic recording. Finally, the natural frequency of the entire system should be as low as possible — 0.3 Hz or less is mandatory. These four requirements imply that the ideal Beg system is one in which subject and bed tloat as a unit in space. Several ingenious systems, some simple, some complex, have been assembled to accomplish the above requirements. Beds have been con- structed from aluminum and canvas, styrofoam. balsa, or aluminum honey- comb, and suspended by wires or floated on mercury or air. The sim- plest and original bed is based on the pendulum, and was the type used in this stud\ . The Beg bed was the same stretcher used to weigh Gigi (Figure 2). The stretcher was constructed from canvas and two 20-fool heavy wall, galvanized steel pipes 3 inches in diameter. The total weight of 227 kg may seem large to most ballisto- cardiographers. but Gigi's weight at the time was 4..'i00 kg. and the whale: Figure 1. — Examples of normal ballistocardio- graphic tracings in man. From top to bottom are recorded acceleration (A), velocity (V). and displacement (D). In addition, the EKG and the major events of the cardiac cycle are given as reference points. (From Scarborough et al.. Am. J. Cardiol. 2:613-641. 1958.) bed ratio of 20; 1 was more than adequate. Six ropes supported the poles, four at the ends, each 13 feet in length, and two in the middle. A board inserted between the two middle ropes prevented injury to the animal. The six ropes were suspended by a single cable from a crane. During the recording the cable was 7'/2 meters from pulley to hook, giving a natural frequency of about 0.18 Hz. The crane was part of a truck hoist, which was ideal for isolation from ground because of the pneumatic lift and the rubber tires. Most of the water was drained from Gigi's tank to reduce her mobility and to enhance our own. She was reluctant to lie on the bed. and had to be coaxed. The coaxing process took 45 minutes. Once on the bed. she became surpris- ingly quiet, which was fortunate, since she could easil\ have demolished our fragile accelerometer. One re- adjustment of the relative position of whale and bed was required to level the bed. Acceleration was transduced in the head-foot direction with an Endevco' piezo-resistive accelerometer clamped to one of the steel poles with a large C clamp. The accelerometer was calibrated with a pendulum, ac- cording to the method of Moss (1961). Lead two of the ECG was recorded using 4 inch 18 g spinal needles. All electrical cables were supported by a rope stretched across the tank. A 60 Hz passive notch filter and a .^d Hz low pass Butterworth filter were used on both the ECG and Beg to eliminate unwanted noise and at the same time preserve timing relations. Data were recorded on a Hewlett-Packard oscil- loscope and an Ampex FM tape rec- order. 'Use of trade names in this publication does not imply endorsement of commercial products by \he National f^arine Fisheries Service. 10 RESULTS Figure 3 shows the Beg recorded from Gigi. In amplitude and form, it is similar to that seen in man. Figure 4 demonstrates that the inlluence of ventilation on the tracing is profound. In fact, during expiration and in- spiration reading the Beg is impossible. Figure 5 displays the Begs of three animals — a mouse, a man. and a whale. Their similarities are more striking than their differences. This similarity holds in spite of differences in body mass and form, amount and distribution of fat. and natural environment. Table 1 lists some measurements derived from the Bcg's of the mouse, man. and a whale. It also gives some fundamental values which are helpful in comparing the species. The Beg has been used to estimate cardiac output and stroke volume in several species. By using the Starr formula (Starr and Noordergraaf. 1967. p. 177- 180) we estimated Gigi's stroke volume to be 7.2 I. and the cardiac output as .^08 1/min (Table I). DISCUSSION One of the major postulated objec- tions to the Beg is that the amount and distribution of body fat can con- siderably alter the recording. This did not seem to be the ease in Gigi. in spite of a 3' 2 inch layer of blubber. It is true that the old direct- body Beg used in the 1950's was subject to influence by body fat. How- ever, the ultra low-frequency bed. by virtue of its light weight and strong coupling between subject and bed. has eliminated most of this inaccuracy. The fundamental natural frequency of the body ("bowl of jelly" phenom- enon alluded to by some in refer- ence to the Beg) does not depend on bod\ mass, amount of fat. or age (Burger. Noordergraaf. and Ver- hagen. 1953; Burger and Noorder- graaf. 1956; Talbot and Harrison. 1955; Tannenbaum. Vessell. and Schaek. 1956; Weissbaek. 1960a. 1960b; Tischenko. 1963). Some of Figure 2. — Gigi. Beg bed. man. and hoist. The accelerometer is being attached to the right side of the proximal pole. The truck was jammed against the retaining wall of the tank. A white rope strung across the tank supports the cables. the higher mode frequencies may depend on the amount and distribu- tion of body fat. A crucial factor in ballistocardiog- raphy is the orientation of the aorta in relation to the body. This is so because usually complexities have forced ballistocardiographers to record the Beg in one dimension, the head-foot direction, instead of the possible three dimensions and six degrees of freedom. Thus if the direction of ejection and runoff is different in different species, the com- parison would be difficult. The orienta- tion of the aorta seems to be no 11 ECG -n ULFBcq^ TIME r^ ,'* — ^ • ,o„ — ^ 1^ ^^ '~\ — ^ '~', ■ f"', — ^ f~\ — ^ r-\ J^ V/vJ^ \ . f^ ^^^v^^W'-'V Figure 3. — ECG lead two and acceleration Beg in a California gray whale. Paper speed - 50 mm/ sec. The Beg calibration of 3 cm/sec- is shown in the lower right. ECG-n '~';—.^ ';—'!' — ^/'~^(^~^,'-^^ — """f^' — "^ r~\'"~^ f'l^ f-\ '^r-^^«*- /,-^'^~~-^'' — '^r^''~~^r~^'' — ",'"'■ ULF Bcqo TIME ^^AJ';U\wA^wvA^\^;'vvv';V^ ■ ,^ , /. v^^v'^'"'^'-'^^ . J «v Figure 4. — The Beg with Gigi during one breath. Paper speed = 25 mm/sec. The respiratory influence on the Beg is considerably greater in the whale than other species. This is probably due to the necessarily rapid and large tidal exchange. MOUSE An 17.25. R I9h, 27.04g . 16.8.68 ,v— Av-v^/W-^^i^V^^ 2cm -lO.lmV MAN ULF Be q„ A^v^/yA^~^YV-^YV-'Y^ ^ ECG-n- WHALE ECG-n ULF Bcg„ TIME -V^^ — \^^ — V-^ 3cm sec 2 Figure 5. — The ultra low-frequency acceleration Bcg's in a 27-gm mouse (top record), a 73.000-gm man (middle record), and a 4.S00.000-gm whale (lower record). The ECG s are also shown. Note the more rapid paper speed in the mouse Beg. Considering the 167.000-fold difference m body mass, as well as the differences in body shape, amount and distribution of fat. and instrumentation, the records are remarkably similar. The mouse Beg is from Juznic. G., Bibl. Cardiol. 26:281-291. 1970. The human Beg is courtesy of Dr. Aaron G. Dinaburg. different in the whale from other mammals. Green (1971) describes the course and relations thus: "Leaving the left ventricle, the aorta makes the characteristic left arch before passing superficially and caudally to lie just under the center of the thoracic cavity to pass through the diaphragm." Body acceleration, which is closely related to blood acceleration, is a constant factor among various mam- malian species. A peak-to-peak body acceleration of 2.5-5 cm/sec- (about 2.5-5 millig) seems to be optimum. If the acceleration is greater, as with severe aortic insufficiency, the slight motion now becomes quite noticeable. If the whale's body acceleration were proportionateK large in relation to its mass, the motion could become un- comfortable. Why a smaller normal acceleration would not be feasible, or indeed why an initial ventricular impulse is necessary at all. is difficult to guess. Other constants occur among mammals. For example, with rare exceptions such as the giraffe, arterial blood pressure is very similar in differ- ent species (Altman and Dittmer. 197 1. p. 405-4(18). One could spec- ulate why these values are so appro- priate. If normal arterial pressure were higher, either the vessel walls would have to be of considerably stiffcr material, or the\ would have to be so thick that the ratio of wall thick- ness to lumen would be impractical. If normal pressure were lower, perfu- sion through the necessarily small capillary vessels would be diflicult. Perhaps even more pertinent a con- stant involves the relative masses of the heart and body in different mam- mals (Table 1). Apparently there is more variation within species than among species. The general form o\ Gigis Beg is very similar to that given for normal man h\ .Scarborough et al. ( 1958). One can certainly recognize an HIJ ci>m- plex and an LMN complex. It seems that greater differences in amplitude and lorni are caused by faulty tech- nique, such as a heavy bed and poor 12 coupling, or by disease states, than by differences in species. Figure 6 gives an example of this. It compares a virtually normal Beg in a dog with the Beg in a dog at the terminal stages of rejection. The latter tracing is obvious- ly grossly abnormal and demonstrates the extreme in Beg abnormality. Other conditions which can cause a greater ballistocardiographic variation within than among species include anginal attacks, severe coronary artery disease. hyperthyroidism. aortic valvular insufficiency, and congestive heart failure (Starr and Noordergraaf. 1967). Even a pro- gram of physical conditioning over several months can alter an individual's Beg to as great an extent as the differ- ences seen among species (Elsbach et al., 1970, Holloszy et al.. 1964). The major difference among the Bcg"s of various mammals seems to be one of timing of the systolic wave forms. As body size increases, the on- set of the systolic complex is delayed (QH interval) and the complex spreads out (HJ and HI. intervals. Table 1). If we consider the tip of the H wave as the onset of ejection, we shall at worst slightly underestimate ihe cardiac pre-ejection period. Certainly the relative values among species can be estimated by the QH interval. Sim- ilarly, ejection time can be estimated by the HL interval. This interval did not seem to be so relatively prolonged in Gigi as the QH. The contribution of prolonged conduction time in hearts of different sizes to the inter- species differences in systolic time intervals is probabK considerable, as is shown b\ the PR and QRS intervals in Table 1 . In general, heart rate and ejection time are inversely related. Thus part of the differences in systolic time intervals is due to heart rate differ- ences. But heart rate cannot explain all of the differences. Gigi's heart rate of 43 beats/min was not as slow as expected and occurred presumably because she was excited. An athlete with a heart rate of 40-45 beats/min does not show the prolonged pre- Table 1. — Some comparative values among mouse, man, and whale. Weight (gm) Length (cm) Heart/body mass (gm/100 gm) Heart rate (beats/mm) Beg IJ amplitude (cm/sec-) Beg IJ amplitude (corrected, cm/sec^) Bog IJ amplitude (dynes) Cardiac output (l/min) Cardiac index (Ml/mm/kg) Stroke volume (ml) Stroke index (ml/kg) PR interval (msec) QRS interval (msec) QH interval (msec) "Pre-eiection period" HJ interval (msec) HL interval (msec) "Election time" -t- With tail ■ Corrected for mass of bed IJ = Measured in Gigi I Walker, et al , 1968 - Altman and Dittmer, 1971, p. 240, ' Altman and Dittmer, 1971, p. 236-7 ^ Altman and Dittmer, 1971, p. 239. Mouse Man Whale Ratio Whale/Mouse 27 6 5-9.5 (12 5-20) + ( 0 41-0 51 (■-) 73.000 ) 180 0 44-0 57(3) 4,500.000 760 0 32-0 50(r) 167,000 38-117 0.78-0 98 300-700 (■•) 2.6(6) 60-80 4 3(6) 43 48 0.13 1.8 3.4- 4.7- 50- 1.5 73.0 250 X ^o■■' (;.») 2 27X lOr 311.000 — 5.0-8 0 70-90 (9.111) 308 68.4 — 42(") 22(11) 27 70-90 (9..I") 0 9-1 2 (9.11) 180-200 80-100 90-110 ('.») 7150 1.6 294" (320) (") 103' (90-120) (It) 320 70 12.9 11.9 43 64 140 ('.8) 320 ('.«) 205 490 4.8 7.7 /Tota!Mass\ :! '^"-"''^-" ^"t°""^^^' ^^^^' " 3"° I p„^, ..,,, I '■ Juznic. 1970 VBody Massy . Starr and Noordergraaf, 1967. « IVloss. 1961 9 Cullen, et al . 1970. I" Altman and Dittmer, 1971, p. 323- " Altman and Dittmer, 1971, p. 278. ECG n 4- 1 1 1 1- 1— ULF BCGa '-wU ^"^-^-ni| Vjw. ',yv-%AA^,^, PG Timo. In seconds Figure 6a. — These (wo tracings are from a conscious dog after cardiac autotransplantation. The Beg is essentially normal. PG = Pneumogram (Whitney gauge). ECG-n ULF BCGa -!^^-- ^-A-.v^->V' PG Time in seconds Figure 6b. — These tracings are from a dog in the terminal stages ol rejection after cardiac allo- transplantation. The difference between the ballistocardiographic records from the two dogs is obviously greater than that between Ihe tracings from a whale and mouse (Figure 5). 13 ejection period and ejection time that Gigi does (Weissler et al.. I960; Leighton et al.. 1971). We said that the Beg is used to estimate cardiac function. This is possible because of the close relation- ship between the acceleration Beg and the acceleration of blood out of the left ventricle into the aorta (Winter et al.. 1966, 1967: Smith. Van Citters, and Verdouw. 1970; Deuchar. 1966). The latter is a proven sensitive indi- cator of cardiac function (Noble. Trenchard. and Guz. 1966; Noble, Gabe. and Trenchard. 1967; Rushmer. 1964. 1970). Gigi's stroke index of 1.6 ml/kg is somewhat greater than that of man. about 1 ml/kg. However, since the heart rate was slower in Gigi, the cardiac index was closer to that of man (Table 1). Again, in comparing several species, we note that when cardiac output is plotted against body weight on a log-log scale, a straight line is obtained (Altman and Dittmer, 1971, p. 320). It does seem reason- able that stroke inde.x is roughly equivalent in different mammals, since the heart/body mass ratios are similar. Although the measurement of acceleration, as opposed to displace- ment or velocity, minimizes the in- fluence of ventilation, any movement or muscular activity can disturb the recording. Since whales must expire and inspire rapidly between dives, the muscular activity is relatively violent. As Wahrenbrock has measured. Gigi's peak instantaneous flow rate was 285 1/sec. Thus ventilation demolished Gigi's Beg recording. Fortunately, ventilatory rate was extremely slow so that the Beg had sufficient time to recover between breaths. The Beg has now been recorded in a wider range of masses in animals than any other physiologic test. The mass ratio is 1;6, 000.000. egg embryo: whale. This points out the versatility of the Beg and suggests its importance as a technique for comparative physiological and pharmacological studies. ACKNOWLEDGMENTS The authors wish to acknowledge the invaluable assistance of Gary Maruschak. They also thank the staff of Sea World who participated in this study. Without their enthusi- astic cooperation, these studies would have been impossible. LITERATURE CITED AUman. P. L., .ind D. S. Dittmer (editors). 1971. Respiration and circulation. Fed. Am. Soc. E,\p. Biol.. Bcthescda. 4tO p. Burger. H. C. and A. Noordergraaf. 19?6. Physical basis of ballistocardiography. IF The quanties that can be measured with ditferent types of ballistocardiographs and their mutual relations. Am. Heart J. 5 1:127-139. Burger. H. C. A. Noordergraaf. and A. M. W. Verhagen. 1953. Physical basis of the low-fretiuencv ballistocardiograph. Am. Heart J. 46:71-83, Cullen. B. F.. E. F Eger. II. N. T. Smith, D. C. Sawyer. G. A. Gregory, and T. A. Joas. 1970. Cardiovascular effects of fluroxene in man. Anesthesiology 32:218- 230. Deuchar. D. C. 1966. The relations of hallistixardiography to other methods of studying the cardiovascular system in man. In A. A. Knoop (editor). Ballisto- cardiography and cardiovascular dvnamics, p. 225-236,' William & Wilki'ns Co.. Baltimore. Elsb,ich. H., F. A. Rodrigo. H. W. H. Weeda. and J. Pool. 1970. The ballistocardiogram in selection for and assessment of physical conditioning in patients with ischemic heart disease. Bibl. Cardiol. 26:49-51. Green. R. F. 1971. Observations on the anatomy of st>me cetaceans and pinnipeds. In S. H. Ridgwav (editor). Mammals of the sea. Biology and medicine. C. C. Thomas. Springfield, p. 269. Holloszv. J. O.. J. S. Skinner. A. J. Barry, and T. K.. Cureton. 1964. Effect of physical conditioning on cardiovascular function. Am. J. Cardiol. 14:761-770. Juznic. G. 1970. The ultra-low frequency ballistocardiogram of the mouse. Bibl. Cardiol. 26:280-291. Leighton. R. F.. A. M. Weissler. P. B. Wein- stein, and C. F. Wooley. 1971. Right and left ventricular systolic time inter- vals. Am. J.Cardiol. 27:66-72. Moss, A. J. 1961. Ballistocardiographic evaluation of the cardiovascular aging process. Circulation 23:434-451. Noble. M. I. M.. I. T. Gabe. and D. Tren- chard. 1967. Blood pressure and flow in the ascending aorta of conscious dogs. Cardiovasc. Res. 1:9-20. Noble. M. I. M., D. Trenchard. and A. Guz. 1966. Studies of the maximum accelera- lit^n of blotid in the ascending .Kirta oi conscious dogs. In A. A. K.noop (editor). Ballistocardiography and cardiovascular dynamics, p. 243-247. William & Wilkins Co.. Baltimore. Rushmer. R. F. 1964. Initial ventricular impulse. A potential key to cardiac evaluation. Circulation 29:268-283. 1970. Cardiovascular dy- namics. 3rd ed. W. B. Saunders Co.. Philadelphia, p. 110. Scarborough. W. R., E. F. Folk. III. P. M. Smith, and J. H. Condon. 1958. The nature of records from ultra-low frequency ballistocardiographic systems and their relation to circulatorv events. Am. J. Cardiol. 2:613-641. Smith. N. T. In press. Ballistocardiography. In A. M. Weissler (editor). Noninvasive methods in cardiac evaluation. Grune and Stratton. New York. Smith. N. T.. R. L. Van Citters, and P. D. Verdouw. 1970. The relation between the ultra-low frequency ballistocardio- gram, the acceleration pneumocardio- gram. and ascending aortic flow accelera- tion in the baboon. Bibl. Cardiol. 26:198-205. Starr. I., and A. Noordergraaf. 1967. Ballistocardiography in cardiovascular research. J. B. llippincott Co.. Phila., 438 p. Talbot. S. A., and W. K. Harrison. Jr. 1955. Dynamic comparison of current ballisto- cardiographic methods. Part I: Artefacts in the dynamically simple ballistocardio- graphic methods. Circulation 12:577-587. Tannenbaum, O., H. Vessell. and J. A. Schack. 1956. Relationship of the natural body damping and body frequency to the ballistocardiogram. Circulation 13:404-409. Tischenko. M. 1. 1963. The significance of natural vibrations of the human body in shaping the ballistocardiogram. Bio- physics 8:311-319. Walker. E. P. 1968. Mammals of the world. Vol. II. Johns Hopkins Press. Baltimore, p. 921. Weissbach. G. H.-J. 1960a. Die Rolle der Tischmasse und der Wert einer zusatzlichen Diimpfung beim Elongations- ballistokardiographcn. [In Ger.) Pflue- gers Arch. ges. Physiol. 270:529-535. 1960b. Die registrier- technischen Eigenschaften des direklen ballistokardiographen. Z. Kreislaufforsch. 49:626-630. Weissler. A. M.. R. G. Peeler, W. H. Roehll, Jr., and N. C. Durham. 1960. Relation- ships between left ventricular ejection time, stroke volume, and heart rale in normal individuals and patients with cardiovascular disease. Am. Heart J. 62:367-378. Winter, P. J., D. C. Deuchar, M. N. Noble, and A. Guz. 1966. The ballistocardiogram and left ventricular ejection in the dog. In A. A. Knoop (editor). Ballistocardiog- raphv and cardiovascular dynamics, p. 248-254. Williams c<; Wilkins Co.. Balti- more. Winter, P. J., D. C. Deuchar. N. 1. M. Noble, et al. 1967. Relationship between the ballistocardiogram and the movement of blood from the left ventricle in the dog. Cardiovasc. Res. 1:194-200. MFR Paper 1046. From Marine Fisheries Review, Vol. 36. No. 4. April 1974. Copies of this paper, in limited numbers, are available from D83. Technical Informa- Division. Environmental Science Information tion Center. NOAA. Washington. DC 20235. 14 MFR PAPER 1047 Investigation of Blubber Thickness in a Gray Whale Using Ultrasonography MICHAEL P. CURRAN and WILLIAM M. ASHER ABSTRACT A captive juvenile i;ray whale. Eschrichtius robustus. was studied with tdtra- soiind using A-mode technique. Measurements of hiuhher and fat titickness by means of selected tissue interfaces were made. Suture implantation depths were also measured. Ultrasound woidd he a reliable method for measiirini; hiuhher and fat thicknesses to .y/ic insiiiht to a marine moiitmal's nutritional status. PROBLEM A captive yearling gray whale was considered for ultrasound study 1) to measure blubber and fat thickness to reflect on nutritional status, and 2) to measure depth of polyethylene suture implantations being used for an attachment of a radio transmitter de- vice on the animal's dorsal surface. PROPOSAL Using an ultrasound beam with A-mode technique, it was proposed to measure skin, blubber, fat. and muscle depth. Tissues of varying density will reflect ultrasound echoes from their respective interfaces. A porpoise. Tur- siops truncutus. model was proposed for correlation. BACKGROUND Ultrasound is a relatively new sci- ence which is meeting with intense interest and enthusiasm for medical diagnostic and research purposes. It has proven effective in detecting brain midline shifts with the echoencephalo- gram. Examinations of the heart to predict cardiac output, mitral valve activity, and presence or absence of pericardial effusions are made. B-scan examination of the abdomen to localize and characterize various masses and organs in the peritoneal cavity and retroperitoneal space is accepted prac- tice. Obstetrics has found valuable use for ultrasound in evaluating gestational age. placental location, and pelvic masses. In the field of veterinary medicine this technique has made it possible to select breeding stock by determina- tion of the fat and muscle interfaces, allowing identification of those ani- mals with the best commercial poten- tial. This latter application suggested measurements for marine animals to evaluate nutrition. MATERIALS AND METHODS Utilizing commercially available pulsed ultrasound equipment designed for medical application, multiple measurements of the echo interfaces of the gray whale were obtained at selected positions along the dorsal- lateral aspect and axilla. Additional measurements were obtained over the polyethylene sutures to determine the Lt. Conidr. Michael P. Curran, MC. USNR, and Lt. Comdr. William M. Asher, MC, USN, are both from the Department of Ultrasound and the Clinical Investigation Center, Naval Hos- pital, San Diego, CA 92134. The opinions or assertions con- tained herein are those of the authors and are not to be con- strued as official nor as reflecting the views of the Navy Depart- ment. suture depth. All of this material was displayed on a cathode ray oscillo- scope with a linear scale divided into millimeter increments. As an in vitro correlation to provide information as to which structures were providing the echo interfaces observed in the live mammal, a porpoise model with necropsy section was obtained. Using a direct visual placement of the trans- ducer in similar areas to that of the gray whale, the echo interfaces were photographed on the oscilloscope. Direct linear measurements and ana- tomical identification of the structures traversed were performed. These echo patterns correlated highly with the similar patterns obtained from the gray whale and indicated which struc- tures were providing these echoes. Thin section radiographs were ob- tained of the porpoise model, further demonstrating the density differences of tissue between the skin lines, blub- ber, areolar fat, muscle, and fascial surfaces. In all cases the measurements corresponded exactly to the visual interpretation of the fascial, fat, bone, and skin interfaces. DISCUSSION Elementary Ultrasound Physics Although ultrasonic technology in medicine is relatively new, the earliest experiments date back to the I800"s when attempts to produce high fre- quency sounds were performed. In 1883 Gallon developed an ultrasound whistle which was capable of produc- ing vibrations as high as 25,000 cycles per second. In modern terminology, the frequency of vibrations is assigned the term "Hertz"' and 25,000 cycles per second is abbreviated as 25 kilo- heriz (25 kHz). In 1929 Sokolov de- scribed an ultrasonic method for de- tecting flaws in metals. Following this, in l')47. this new modality was utilized in medical diagnosis when early workers such as Keksell. in Sweden, demonstrated the ability to delect the midline of intracerebral structures. 15 Electrical to Mechanical Mechanical to Electrica Figure 1. — Piezoelectric eftect Figure 2. — Split function concept. Pulsed ultra- sound from transducer is transmitted 10% of the time and received 90% at 400 pulses/sec. Ultrasonics, the technology of high frequency sound waves, deals with the transmission of sound or pressure waves through a medium. Sound waves, unlike electromagnetic waves, cannot be transmitted through a vac- uum. The generation of sound waves from a transducer depends on a phe- nomenon known as piezoelectric ef- fect. This effect is produced when electrical energy is applied to a crystal which, when distorted by this electri- cal energy, will produce a mechanical pressure wave. In reverse, the piezo- electric effect occurs when mechani- cal energy distorts the crystal, pro- ducing an electrical potential which can be measured. The technique of recording reflected ultrasound results from this reversible behavior. (See Figures 1 and 2.) Sound waves travel through various materials with char- acteristic velocities. The product of the density of the material and the velocity of sound through the given material is called "characteristic acous- tic impedance" (Zl. When the two substances adjacent to each other transmit sound at a different velocity, the ultrasonic reflection (/?) at the boundary is determined by the ratio of the two acoustic impedances as described in the formula A f ^=-f- 1.5 OO 5,000,000 cyC/ If the two substances have the same acoustic impedance, the numerator becomes zero and there is no reflection. On the other hand, if there is a large difference between the acoustic im- pedances, the result approaches unity, and almost all of the energy is reflect- ed. In between these two extremes some of the sound energy is reflected while that remaining passes through the interface. Since most soft tissues have acoustic impedances that are quite similar, there are relatively weak reflections at the boundaries. The air- tissue interface is the strongest biologi- cal reflector. The bone-tissue inter- face, likewise, produces a very strong reflection. As most reflections are rela- tively weak, sensitive equipment is re- quired to detect those boundaries with the less strongly reflected echoes and interfaces such as fat-muscle. What is the resolution of the sys- tem? The frequency of sound deter- mines its wavelength. The resolution is likewise dependent on the wave- length in the axial direction. The high- er the frequenc) . the smaller the wavelength; thus, we have a better resolution capabilits as determined by the formula r = X/ where r is the velocity of the sound in the medium. X is the wavelength, and / is the fre- quency. We assume that the minimum distance between two objects for dis- = 3x10"^ = 0.3 mm = A A X 1.5 = Minimum Distance Between T\a/o Objects for Discrimination. = 0.45 mm For 5 mhz Figure 3. — Formula lor resolution. crimination must be equal to at least l'/2 wavelengths. (See Figure 3.) By going to higher frequencies, however. we lose penetration in tissue due to sound attenuation: therefore, a com- promise must be made and the fre- quency selected which gives adequate axial resolution, yet adequate penetra- tion through the tissue thickness. For the mammalian models studied the frequency varied between 1 and 2 megahertz, which was adequate for penetration through the structure studied. Findings Although the size dilterence be- tween the 28 foot captive gray whale and the captive Atlantic bottlenosed dolphin {.Titrsiops nuncaliis) necrop- sy model is somewhat different, the anatomical structures of the mammals are known to be similar. During periods of illness or mal- nutrition, marine mammals of these species are noted to develop a depres- sion in the dorsal contour posterior to the axilla. It is thought that this de- pression is due to catabolism of blub- ber, areolar fat. and/or muscle mass loss. Presuming ihat areolar fat dimin- ishes in volume prior to muscle loss. Figure 4. — Radiograph of Turs/ops cross sec- tion demonstrating (1) blubber. (2) areolar lat. (3) muscle group to fascial layer, and (4) second deep muscle group to dorsal spinous process. 16 17 18 one could measure the normal thick- ness in heahhy mammals and compare with abnormal animals and any avail- able necropsy specimens. As a pilot program, echographic measurements were made in both the gray whale. E. robitstus. and the porpoise. T. nunccUiis. Necropsy cor- relation in Tursiops showed that the measurements were easy to perform and were highly accurate. (Figures 4-8.) Applications Figure 6. — A-scan of Tursiops cross section. Lettered spikes conform to radiograpfis and tissue boundaries as measured in necroscopy section: (A- B) blubber ttiickness = 2 cm. (C-D) fat thickness = 1 cm, and (D-E) muscle ttiickness = 8.2 cm. Ideally, to make this method most useful, measurements should be made and necropsy correlation measure- ments obtained whenever these mam- mals are found deceased. Due to the expense and shortage of the species, flying a small team to the animal site with the easily portable battery or generator operated scanning equip- ment should be the most effective means of collecting this invaluable data. Further observations on the nutri- tional status during development com- paring captive and free animals, as well as disease effects, should prove to be a new approach to the study of marine mammals. Such research data, if accumulated, may be of great bene- fit in the protection and treatment of valuable, trained marine mammals and their free swimming counterparts. CONCLUSION A-mode echography is an effective means of measurement of tissue layers and should be an effective tool in the study of marine mammal nutrition and health status. Figure 7. — A-scan of gray wtiale dorsal-lateral surface posterior to axilla demonstrat- ing blubber thickness of 4.1 cm (A-B) and fat thickness of 4.6 cm B-C). C represents fat-muscle interface. Figure 8. — A-scan of gray whale for polyethylene suture localization. (A) Skin. (B) Blubber-fat interface at 3.5 cm. (C) Polyethylene suture at 5.5 cm. (D) Fat-muscle interface at 7 cm. Figure 5. — Radiograph of Tursiops cross section demonstrating (A) skin-blubber interface, (B) blubber-fat interface, (C) fat-muscle interface. (D) muscle-fascial layer interface, and (E) re- flective bone (dorsal spinous process). 19 REFERENCES Ashcr, W. M.. und A. K.. Freimanis. 1%^. Echographic diagnosis of retroperitoneal lymph node enlargement. Ultrasound scan- ning technique and diagnostic findings. Am. J. Roentgenol. Radium Ther. Nucl. Med. 105:438-445. Freimanis. A. K., and W. M. Asher. 1970. Development of diagnostic criteria in echographic study of abdominal lesions. Am. J. Roentgenol. Radium Ther. Nucl. Med. 108:747-755. Grossman, C. C, J. E. Holmes. C. Jovner, and E. W. Purnell (editors). 1966. Di- agnostic ultrasound. Proc. First Int. Conf. Univ. Pittsburgh, 1965. Plenum Press, New York, 5 19 p. Lehman, J. S. 1969. Ultrasonography. Delaware Med. J. 40:24-25. Okasawa, A., and L. Hakkinen. 1969. Comparative experiments on the attenua- tion of ultrasound in muscular and fat tissue. Acta Aphthal (Kohenhavn) 47:735. Strakova, M.. and J. Markova. 1971. Ul- trasound use for measuring subcutaneous fat. Rev. Czech. Med. 17:66-73. MFR Paper 1047. From Marine Fisheries Review, Vol. 36, No. 4, April 1974. Copies of this paper, in limited numbers, are available from D83, Technical Information Division, Environmental Science Information Center, NCAA. Washington. DC 20235. MFR PAPER 1048 MATERIALS AND METHODS Surgical Attachment of a Telemetry Device to the Dorsal Ridge of a Yearling California Gray Whale, Eschrichtius robustus JOHN C. SWEENEY and JOEL L. MATTSSON ABSTRACT Siiri^iccil atuichiiu'iil of an instrument packufie moiiniinf^ device onto the dorsul rUli;e of a yenrliiii' feinnle California i-ray whale. Eschrichtius robustus, wa.\ accomplished lhroui;h the utilization of four lariie polypropylene sutures. Use of polypropylene and polyester fabric meshes to induce tissue i;ronth aroutid the sutures was not successful. Post-operative therapy was heneficial in iiisuriui.; adequate healing at the suture sites. The original polypropylene sutures were replaced the day before release by polyvinyl chloride coated stainless steel. INTRODUCTION In March 1971, an infant female gray whale was captured within Scammon's Lagoon, Baja California, and subsequently transported by boat to Sea World, Inc. in San Diego. Calif. The animal was captured for research purposes, and for the year following her capture, various studies were un- dertaken. As the animal approached 1 year of age. the financial burden to Sea World in holding facilities, personnel, and food made it necessary to design a plan for her release. At that time. W. E. Evans, of the Naval Undersea Center. San Diego, proposed (with the support of the National Oceanic and Atmospheric Administration) that the whale be released carrying a telemetry device for tracking and recording. Evans (1971) has reported the use of radiotelemetry devices attached to the dorsal fin of dolphin, using a bolt placed through the tin. Martin. Evans, and Bowers (1971) have utilized a harness for the fixation of a device onto a pilot whale. A gray whale has no dorsal fin for bolt fi,\ations. and the growth rate of this animal left the harness method undesirable. There- fore, a surgical fixation was considered the method of choice. J«»hn C. Sweeney and Joel L. Maltsson are associated with the Naval Undersea Center, San Diego, C A 91132. Sutures composed of .■* mm diame- ter polypropylene were swaged onto a stainless steel needle made from 3 mm diameter rod shaped into a 10 cm diameter half circle. Pohpropylene was chosen because of its inert nature in mammalian tissues (Usher et al., 1962) and because of its availability in the dimensions required. Two types of prosthetic mesh were used in con- junction with the sutures, polypro- pylene (Marlex®') mesh and polyester fiber (Mersilene*-). Five weeks before the scheduled re- lease, an attempt was made to place polypropylene mesh pads (2 cm X 2 cm) subdermally at the entrance and exit sites of the four proposed sutures at positions on a longitudinal plane 10 cm to either side of the dorsal ridge and 10 cm apart. The intention was to induce collagen fiber infiltra- tion within the fabric to add strength to the skin and to prevent infiltration of water once the sutures were in place. The skin was closed with simple inter- rupted nylon sutures. Four weeks before release the four polypropylene sutures, each having had a sheet of polyester fabric at- tached to it using Eastman 9-10 ad- hesive.'' were placed at the proposed sites. Depth of penetration of the su- tures was later confirmed by ultrason- ography to be from 4 to 6 cm (Curran 'Cavol. Inc., Providence. R.I. Reference to trade names does not imply endorsement by the Na- tional Marine Fisheries Service, NCAA -Ethicon. Inc , Scmerville, N J ^'Eastman Chemical Products, Kingsport, Tenn, 20 and Asher. 1974) all King within the I'attN tissue between blubber and muscle. Once in position, the suture ends were temporarily fused, each suture forming a ring enclosing the dorsal ridge (Figure 1). Each surgical procedure was done under local an- esthesia, using 2 percent Xylocaine. RESULTS Both attempts to utilize mesh fabrics were unsuccessful. Because no fascial interface is present between epidermis and dermis, or dermis and hypodermis. in cetaceans, placement of mesh pads under the skin was not accomplished. After attempts were made at two of the operative sites, it became apparent that it would be too difficult to embed the pads properly. In addition, the sutures cut through the epidermis when even light tension was applied, preventing adequate closure of the incision. Because of these problems, the procedure was not completed. Within 5 days, each of the mesh pads had been sloughed. The mesh coated sutures did not induce tissue infiltration, but rather, acted as an irritant with a consequent tissue inflammatory response. Some drainage from the suture holes was observed on the third post- operative day. and at this time, all four sutures were easily moved back and forth within their tissue bed. The exudate was composed of clear, non- viscous fluid containing tags of white coagulated matter dispersed through- out. Cellular composition was 70 per- cent mature neutrophils and 30 per- cent lytnphocytes. Swabs were taken on the third postoperative day and on two subsequent occasions. No bacteria were found. Daily flushing of each suture site with normal saline and nitrofurazone solution was done for the ne\t three postoperative weeks. At no time did the animal appear sick, nor was there any indication in her blood tests to suggest that an infection Figure 2. — Normal healing around polypropylene sutures. Figure 1. — Polypropylene sutures in position with ends (used, forming a ring enclosing the dorsal ridge. 21 was present. By the end of the 3 week postoperative period, normal healing was considered well underway (Figure 2). and there was. by then, no drainage from any of the suture sites, though the sutures were still freely movable. One week before the scheduled re- lease, the instrument package saddle was mounted onto the sutures to allow the animal time to adjust to it before adding the somewhat heavier (approxi- mately 6 kg) instrument package itself. The animal occasionally rubbed the saddle against the side of the tank until the attachment was tightened to reduce free-play of the saddle as the animal swam. On the day before re- lease, cracking of the polypropylene sutures was noticed, requiring their replacement with sutures of the same diameter composed of polyvinyl chlor- ide coated stainless steel. These were found to be more pliable and stronger than the polypropylene. At the last visual sighting of the animal on 7 April 1972. the instru- ment package was still securely at- tached despite the fact that, on several occasions, kelp had been seen trailing from it (J. S. Leatherwood. pers. comm.). At this time, we have no in- dication that this procedure has. in any way. compromised the ability of this animal to survive. LITERATURE CITED Curran. M. P., and W. M. Asher, 1974. Investigation of blubber thickness in a gray whale using ultrasonography. Mar. Fish. Rev. 36(4): lS-20. Evans. W. E. 1971. Orientation behavior of delphinids: radio telernetric studies. Ann-N.-*'. .Acad. Sci. 188:142-160. Martin, H., W. E. Evans, and C. A. Bowers. 1971. Methods for Radio Tracking Ma- rine Mammals in the open sea. IEEE Eng. in the Ocean Environ. Conf. p. 44-49. Usher, F. C, J. E. Allen, Jr., R. W. Crosth- wait, and J. E. Cogan. 1962. Polypro- pylene monofilament. A new biologically inert suture tor closing contaminated wounds. Am. Med. Assoc. 179:780-782. MFR Paper 1048. From Marine Fisheries Review, Vol. 36, No. 4. April 1974. Copies of this paper, in limited numbers, are available from D83. Technical Informa- tion Division, Environmental Science Information Center, NCAA, Washington, DC 20235. MFR PAPER 1049 Some Hematologic Observations on the California Gray Whale ALFRED ZETTNER ABSTRACT E.Kiiininalitin of llic blood of the California i;ray whale, ohlaiiwil .shortly after its arrival at Sea World, San Dieijo revealed the followiiti; data: H'BC-IJI.^ X \0->lciihic mm: RBC-2.4 X IO<^jcuhic mm: hemof^lohin-IO.O gjlOO ml: hematocrit-31 percent: MCV-128 jj-^: MCH-42.8 tijdii: MCHC-32.4 percent. Hemonlohin electrophoresis showed a sini;le hemof^lohin hand with a mobility similar to that oj human hemoi;lobiii /•'. I he whale hemoiilobin was 100 percent alkali resistant. No changes of this hemoi;lobin were seen on repeated analyses over the course of 12 months. The capture of a young, female California gray whale. Eschrichiiits rohitstiis, in .Scammon's Lagoon, and its maintenance in captivity at Sea World, San Diego for 12 months pro- Alfred Zetlner is a physiciun with the Division of Clinical Palholouy, Depart incnt of Palii- olosy. School of Medicine, L'ni- versitv of California, San Diego, CA 92103. vided the opportunity for some hema- tologic studies which are to be report- ed here. ROUTINE BLOOD EXAMINATION A heparini^ed blood sample ob- tained on 18 March 1971. one day after the arrival of the whale at Sea World, was brouuht to the Clinical Laboratories of University Hospital. University of California. San Diego. The blood was analyzed on a Coulter Counter.' Model "S". which allows the automatic simultaneous determin- ation of cell counts, mean corpuscular volume (MCV). and hemoglobin con- tent. The hematocrit, mean corpuscu- lar hemoglobin (MCH). and the mean corpuscular hemoglobin concentra- tion (MCHC) are automatically com- puted from the three parameters measured (Pinkerton et al., 1970) The instrument is standardized twice daily and performs approximately 200 analyses per day for clinical purposes. The results were the following: WBC-13.9 X lO^Vcubic mm RBC-2.4 X lO'Vcubic mm Hemoglobin- 1 0.0 g/ 1 00 ml HCT-3 I percent MCV- 128 /J-' MCH-42.8;ttiUg MCHC-32.4 percent A blood smear was prepared and stained by the automatic HEMA- TEK- technique, which employs a 'Coulter Electronics, Inc , Hialeati. Fla Refer- ences to trade names does not imply endorse- ment by ttie National tvlarine Fistienes Service. NOAA. ^Ames Company. Division of Miles Laboratories, Inc. Elktiart. Ind 22 moditicd Wrighl-Giemsa slain, and examined by oil immersion microscopy. The red cells were round, moderate- ly anisocytotic ranging from 7.5-9.5 /i in diameter, and appeared well hemo- globinated with only occasional slight central pallor. An occasional red cell displayed polychromasia. and some rare Howell-Jolly bodies were seen. No nucleated red cells were encoun- tered. A white cell differential count was as follows; Segmented neutrophils b^ percent Band forms 19 percent Metamyelocytes < 1 percent Monocytes 9 percent Lymphocytes 8 percent No eosinophils nor basophils were en- countered. The lymphocytes were all of the large type. No small lympho- cytes with the typically scant cyto- plasm and dark staining nuclei were present. Twenty-one percent of the nuclei of the mature, segmented neu- trophils had distinct '"drumstick" ap- pendages. The thrombocytes appeared as round platelets, with diameters ap- proximately one-third to one-half of those of the red cells. Their number, estimated from their frequency distri- bution on the smear in relation to the erythrocytes, was in the range of 300.000-350,000/cubic mm. HEMOGLOBIN ELECTROPHORESIS Hemoglobin electrophoresis was performed by the vertical acrylamide gel technique as described in detail elsewhere (Bierman and Zettner. 1967) (Nakaniichi and Raymond. 1963). Briefly, a toluene hemolysate of the washed red cells is prepared and elec- trophoresed in Tris-buffer of pH 9,0 for 3'/2 hours at 120 ma. The acryla- mide gel slabs are then stained with amido black and destained electro- phoretically in 5 percent acetic acid. The results are shown in Figure 1. The whale hemoglobin (Slots Nos. I and 7) migrated slightly slower than human hemoglobin A. The position SLOT I 3 4 5 6 7 6-9'71 Whale non-heme protein (Whale Carbonic Anhydrase ?) Human Corbonic Anhydrase B Humon HbAg Human HbS Gray Whale Hb Human HbA fill • Figure 1. — Vertical acrylamide gel hemoglobin electrophoresis. Tris-buffer, pH 9.0. The gel contains the toluene hemolysates of the following: Slots No. 1-gray whale; No. 2-human with A-S trait; No. 3, 4- normal humans; No. 5.6-standards; No. 7-gray whale (same as slot No. 1). Original (sample application slots) at top. Cathode-lop; anode-bottom. of the band of the whale hemoglobin was indistinguishable from that where human hemoglobin F-' would be ex- pected. No minor hemoglobin com- ponents equivalent to those found in human blood could be detected. The weakly stained band of much slower mobility, as shown in Figure I, is a non-heme protein, as indicated by the failure of this protein band to react with benzidine when a freshly electro- phoresed, unstained strip of the gel containing the whale sample was sub- mersed in a benzidine and peroxide solution. The pattern of hemoglobin electro- phoresis performed on blood samples obtained on 17 March and 27 April 1971, and 13 March 1972 was iden- tical to that demonstrated here. ALKALI DENATURATION A quantitative alkali denaturation test performed on the toluene hemoly- sate by the method of Singer, Chernoff, and Singer ( 195 1) revealed the whale's hemoglobin to be 100 percent alkali resistant. The alkali resistance of the hemoglobin was the same in all sam- ples obtained over the course of 1 year, as listed above. DISCUSSION The values of the various red cell parameters, as reported here, are in fair agreement with those published by Lenfant (1969). Relative to most ter- restrial mammals, the California gray whale appears to have lower red cell counts, hemoglobin concentrations, and hematocrits, although the MCV is considerably in excess of 100 jU^. A proportional increase of the MCV of red cells with total body length of marine mammals of different species has been shown (Lenfant. 1969). Of interest is the finding of Lenfant ( 1969) of a high proportion of nucleated red cells in the gray whale. This is in distinct contrast to the complete ab- sence of nucleated red cells in the blood samples examined here. It should be considered that the previous observations were apparently made on sick, wounded, dying, or dead animals: and that under these abnormal condi- tions, immature red cells may have been released into the circulation. The only indication of young red cells in our samples were the rare Howell- Jolly bodies and occasional polychro- masia. 23 The white cells were remarkable in that no small lymphocytes, eosinophils, or basophils were seen. Otherwise, their numbers and percentages appear to be near the normal limits. Of interest is the occurrence of "drumstick" ap- pendages in 21 percent of the mature segmented neutrophils. These were described by Davidson and Smith (1954) in human blood as a genetic sex indicator for females. They occur in 1-17 percent of the segmented neutrophils of all human females and are thought to represent the inactivat- ed X-chromosome. analogous to the Barr body observed in most somatic cells. It can be reasonably assumed that also in the whale, drumsticks in the neutrophils are indicators for the female sex. The uniform electrophoretic mobil- ity of this gray whale's hemoglobin, characteristic of human hemoglobin F. is in accordance with the finding of others (Lenfant, 1969). Of further interest was the hemoglobin's resistance to alkali denaturation. However, no conclusions can be drawn from this coincidental sharing of two physical properties with human hemoglobin F as to functional or structural similari- ties between these two hemoglobins. The reasons for the alkali resistance of certain hemoglobin variants are poorly understood. In the human this is related not only to the presence of gamma chains in the hemoglobin molecule, but also to the structural relationships of the various chains to each other. For instance. Bart's hemo- globin, composed of four gamma chains, is only half as alkali resistant as hemoglobin F, which is a tetramer of two alpha and two gamma chains. The elucidation of the structure of the gray whale's hemoglobin depends on the full analysis of its amino acid sequence. .Such an undertaking can also be expected to provide some evolutionary clues for the California gray whale. From the evidence presented here, it appears that this species possesses only one type of structurally uniform hemoglobin, although the possibility that we are dealing with two or more hemoglobins of identical electropho- retic mobility and alkali resistance cannot be entirely excluded. The band of non-heme protein ap- pears to be analogous to a similar band which is consistently seen in the electrophoretograms of human bloods. In the latter, this is known to represent carbonic anhydrase B. a red cell constituent persistently extracted with the toluene hemolysates. LITERATURE CITED Bicrman, A. H.. and A. Zettner. 1967. A simple electrophoretic method for the quantitative determination of hemoglobin A2. Am. J. e'lm. Palhol. 48: 1.19-146. Davidson. W. M.. and D. R. Smith. 19.S4. A morphological sex difference in the polymorphonuclear neutrophil Icukocvtes. Brit. Med. J. ::6-7. Lenfanl, C 1969. Physiological properties of hlood of marine mammals. In H. T. Andersen (editor). The biology of marine mammals, p. 95-1 16. Academic Press. N.Y. Nakamichi. M.. and S. Raymond. 196,1. Acrvlamide-gel electrophoresis of hemo- globins. Clin. Chem. 9: U.S. 145. Pmkerton, P. H., I. Spence, J. C. Ogilvie, W. A. Ronald. P. Marchant, and P. K. Ray. 1970. An assessment of the Coul- ter counter model S. J. Clin. Palhol. 23: 68-76. Singer. K., A. I. Chernoff. and L. Singer. 1951. Studies on abnormal hemoglobins. 1. Their demonstration in sickle cell anemia and other hematological disorders by means of alkali denaturation. Blood J. Hematol. 6:413-428. MFR Paper 1049. From Marine Fisheries Review, Vol. 36, No. 4. April 1974. Copies of this paper, in limited numbers, are available from D83, Technical Information Division. Environmental Science Information Center, NOAA. Washington, DC 20235. MFR PAPER 1050 Some Coagulation Factors in Plasma from a California Gray Whale, Eschrichtius robustus W. MEDWAY ABSTRACT .4 cilniled pkisimi sample was assayed for some couiiuhnion faelors. The levels ohiaineil were compared with those from some of ihe small tooilied whales. Factor XII activity was verx low in the i^rav whale sample, whereas toothed whales have none. INTRODUCTION Many people working with small odontocete whales in captivity have made the observation that whale blood has a prolonged clotting time. Since this observation was made two reports have described the lack of clotting Factor XII in blood in some of the smaller whales (Lewis, Bayer, and Szeto, 1969: Robinson, kropat- kin, and Aggeler, 1969). Another pub- lication reports a prolonged clotting time of blood from other small whales: however, assays for Factor XII were not made (Ridgway, 1972). There were no reports of similar studies on blood from any baleen whale: hence this report on some studies on a plas- ma sample from a captive California gray whale. Eschrichtius rohiistiis. 24 MATERIALS AND METHODS A titrated plasma sample was ob- tained from a young ( 1-2 years) female California gray whale kept in cap- tivity in San Diego. Calif. The sample was deep-frozen and shipped via air express to Philadelphia where the assays were made. The plasma sample was slighth llpcmic. The prothrombin time, partial thromboplastin time. Factor V. Factor XI, and Factor XII assays were made in the Coagulation Laboratory at the Hospital of the UniversitN of Pennsylvania. It was not possible to do a fibrinogen assay on the sample. Standard laboratory procedures em- pkning commercial reagents were used to conduct the assays, with the e.xception of Factor XII where dol- phin, Tiirsh'ps iniiucims. plasma was used as the substrate. Plasma reagent from Factor XI deficient cattle was used for the Factor XI assay. RESULTS AND DISCUSSION The results of the assays on the gray whale plasma and some results on a few odontocete whales, from the literature, are shown in Tabic I . The divergence of our results on the gray whale plasma for prothrom- bin time, partial thromboplastin time. Factor V, and Factor XI assays from those of the two species of odontocete whales can be explained perhaps on the elapsed time between sampling and assay. The presence of a low level of Factor XII in the gray whale plas- ma to the non-existence in odontocete plasma warrants some consideration. The significance of this difference teleologically is not known. One of the problems encountered by deep diving humans is decompression sick- ness. This sickness is attributed to the formation of microdots (disseminated W. Medway Is associated with the Department of Clinical Studies, School of Veterinary Medicine, University of Pennsyl- vania, Philadelphia, PA 19104. Table 1. — A comparison of some clotting factors between odontocete whales and a baleen whale The numbers in parentheses indicate the number of samples. Tursiops Orcinus orca- Eschnchtius robustus Prothrombin time (sec) Partial thromboplastin time (ptt) (sec) Factor V(%) Factor XI (%) Factor XI t {%) 17.0(14) 15.6(3) 26.5(1) 346 (15) 216 (3) 107 (1) 136 (14) 239 (3) 17 sec (1) 92.7(14) 146 (3) 24.6(1) 0 (15) 0 (3) 3.4(1) ' Lewis, Bayer, and Szeto (1969) - Robinson. Kropatkin, and Aggeler (1969). ■1 Ridgway (1972). intravascular coagulation) with re- sulting consequences. It is known that slow-moving acid blood has a pro- pensity to clot faster. This property has been attributed to activation of Factor XII and subsequent clot for- mation. Whales dive deeply and are not be- lieved to suffer from decompression sickness. Perhaps the lack of Factor XII or low levels of it is nature's way of protecting the animals. ACKNOWLEDGMENTS The author wishes to express appre- ciation to H. A. Wurzel. Director. Coagulation Laboratory. Hospital of the University of Pennsylvania, and his staff as well as to J. C. Sweeney, Naval Undersea Center, San Diego, Calif, for providing the opportunity to make this study on the gray whale. LITERATURE CITED Lewis. J. H., W. L. Bayer, and I. L. F. Szeto. 1969. Coagulation factor XII deficiency in the porpoise. Tursiops Inimatits. Comp. Biocheni. Physiol. .M:667-(-70. Robinson. A. J., M. Kropatkin. and P. M. Aggeler. 1969. Hageman factor (factor .XII) deficiency in marine mammals. Sci- ence (Wash.. D. C.) 166:14:0-14::. Ridgway. S. H. 197:. Homeostasis in the aquatic environment. In S. H. Ridgway (editor). Mammals of the Sea. p. 65.^. Charles C. Thomas. Springfield. MFR Paper 1050. From Marine Fisheries Review. Vol. 36. No. 4. April 1974. Copies of this paper, in limited numbers, are available from D83, Tecfinical Informa- tion Division, Environmental Science Information Cen- ter. NOAA. Wasfiington. DC 20235. MFR PAPER 1051 Fluorescent Karyotype of the California Gray Whale DEBORAH A. DUFFIELD ABSTRACT The Jhion-.sccnl kuryolypc of the California .i;ray nhale. Eschrichtius robustus, is presented and the aae of the fluorescent handini; tecltniqiie for distini;uishini,' between various cetacean karyotypes is discussed. The California gray whale. E\ch- (Benirschke's unpublished data cited ricliiiiis rohitstiis (Gibbosus) has a in Kulu, 1972; Arnason. 1972). Since diploid chromosome number of 44 reporting of the gray whale karyotype. 25 B. U X X il H M H n if IS II ti II II It II tt II It Figure 1. — Karyotype of the California gray wfiale, Gigi. The autosomes are arranged into four groups based on centromere positron and relative size. Tfie provisional X ctiromosomes are indicated. prepared by standard honiogeneou.s staining techniques, advances in the differential staining of chromosomes have added another dimension to tcaryotypic analysis by making it now possible to individually characterize each chromosome of the complement. Consequently, and as part of a larger cytotaxonomic study of marine mam- mals, evaluation of the gray whale karyotype by quinacrine mustard fluorescent banding was undertaken on Gigi. a captive female gray whale. MATERIALS AND METHODS Chromosome preparations were ob- tained by blood culture (Kulu. Veo- melt. and Sparkes. 1971). Exposure of the cells to 0.075 M KCI for 8 minutes was the preferred hypotonic treatment and cold, rather than tlame- dried. slides were made. The slides were stained with Giemsa for normal karyotyping or with quinacrine mus- tard (50 micrograms/ml buffer for .^0-40 minutes) for fluorescent karyo- typing. Photographs of fluorescent metaphases were taken on Kitdak' Tri-X film with an exposure time of 45-50 seconds. Ten Giemsa and eight fluorescent karyotypes were analyzed. ' Use of trade names m this publrcation does not imply endorsement ot commercial products by ttie National Marine Fistieries Servrce RESULTS Gigis karyotype (Giemsa) is illus- trated in Figure 1. The autosomes are provisionally arranged into four groups (designated A, B, C. and D). Group A is composed of five pairs of large submetacentric chromosomes. Group B of five pairs of medium-sized submetacentrics. Group C of six pairs of metacentrics, and Group D of five pairs of acrocentric chromosomes. Within each group the chromosome pairs are arranged by decreasing size. The presumptive .\ chromosomes are indicated in the karyotype. The fluorescent karyotype of Escli- ritiniiis rohuslus is presented in Figure 2. The arrangement of the chromo- somes follows that of the standard karyotype. The banding pattern of each chromosome pair is distinctive and in addition to allowing positive identification of the homologues makes it possible to characterize each pair of the complement in order to facilitate karyotypic comparison with other species. The fluorescent banding pattern of the presumptive X chromo- Dehorah A. Duftield is with the Deparlmenl of Biology at (he University of California at Los Angeles, Los Angeles, C A 90024. some is the same as that exhibited by the X chromosome of another of the baleen whales, the sei whale. BaUwiiop- icrii horcalis-, and a number of the smaller odontocete cetacean species (personal observation). DISCUSSION The karyotype of the California gray whale appears to be very similar in number and gross morphology to that of a number of other cetaceans, both mysticete and odontocete'' (Kulu. 1972: Arnason. 1972). The fluorescent karyotype of the gray whale was ex- amined in the hope that the resolution of chromosome structure afforded by fluorescent banding would indicate differences between its karyotype and that of other cetaceans not obvious by regular staining methods. In order to illustrate the level of karyotypic com- parison made possible by fluorescent banding, the larger submetacentrics which comprise Group A (pairs 1-5) in two mysticete and two odontocete species are shown in Figure 3. While there are certain similarities between the banding patterns of all four species, it is clearly possible to distinguish between the overall banding pattern of the mysticete (gray whale, sei whale) chromosomes and that of the odontocetes ['l'uisi<>p\ inincaius. Laf-- cnorhyiu hits tihliqiiidciis). Less obvi- ous differences are also present which further distinguish gray whale from sei whale and Tiirsiops from Lugeno- rhyncluis. A detailed comparison of the fluorescent karyotypes of these cetaceans is beyond the scope of this report; however, it can be concluded - Arnason (1972) tias reported ttiat ttie X ctiromo- some of B boreahs is one ot ttie larger ctiromo- somes of ttie complement, sucti as found in other ot the balaenopteran whales However, both standard and fluorescent karyotypes ot a male sei whale, tissue from which was made available to this author by the Richmond whaling station in California, indicate that the X chromo- some of 8. boreahs is of medium size and similar both in relative size and banding pattern to the provisional X chromosome of the odon- tocetes (Kulu, 1972), ■1 Of all cetaceans studied to date, only the sperm, pigmy sperm, and killer whales are karyotypically distinct by standard staining techniques. 26 Figure 2. — The fluorescent karyotype of the California gray whale. Note (hat the members of each pair have identical bands while one pair can be distinguished from any other by its characteristic banding pattern. Figure 3. — Comparison of the banding patterns of four species. Only group A chromosomes are shown and only one chromosome from each pair per species. Species 1 and 2 are mysticetes, 3 and 4 are odontocetes. 27 from these initial observations that the comparison of fluorescent banded karyotypes will significantly enhance the potential contribution which kary- otypic analyses can make to the reso- lution of the phyletic interrelationships of the modern Cetacea. ACKNOWLEDGMENTS My thanks to Sea World and Jay Sweeney of the Naval Undersea Cen- ter. San Diego. Calif, for making the gray whale samples available to me. The fluorescent technique followed in the preparation of the karyotypes is that of Helga Muller. UCLA Medical Genetics Unit. Los Angeles. Califor- nia. This work was supported by a Mental Retardation Training Grant from the Departments of Psychiatry and Medicine, UCLA Medical School. Los Anceles. California. LITERATURE CITED Arnason. U. 1972. The role of chromo- siimal rearrangement in mammalian speci- alion with special reference lo Celacea and Pinnipedia. Heredilas 70:113-118. Kulu. D. D. 1972. Evolution and cyto- genetics. //; S. H. Ridgway (editor). Mammals of the sea. Biologv and medi- cine, p. 503-.'i27. Charles C. Thomas. SpringHeld. Kulu, D. D., I. Veomctt. and R. S. Sparkes. 1971. Cytogenetic com.parison of four species of cetaceans. J. Mammal. 52' 828-832. MFR Paper 1051. From Marine Fisheries Review, Vol. 36, No. 4, April 1974. Copies of this paper, in limited numbers, are available from D83. Tectinical Information Division, Environmental Science Information Center, NCAA. VJashington. DC 20235. MFR PAPER 1052 Some Physiological Parameters of the Blood of the California Gray Whale WILLIAM G. GILMARTIN, RICHARD W. PIERCE, and GEORGE A. ANTONELIS, JR. ABSTRACT HciihUcK ril. (I Oo-Hh iliwiniiUinn curve, unci hlood vahinic luivc hccn clctcr- niiiicil fur a Ccilifoniiti .y/'d.v wIhiIc, Eschrichtius robustus. ninl ihc results arc compcircci lo sonic physioloiiical hlood properties of other celncccins. The E. robustus hii\ n hlooil volume that is similar lo values esiiiinited for lari;e whales hy oilier iiiilhors. This is the firsi lime isolopie teehnicjiies have been used to determine a lariie cetacean's hlood volume. Large cetaceans do not appear to follow the trend of most lerreslerial mammals when the body size and P50 ure compared. The P50 /'"' the E. robustus was 36.5 mm Hi; and is the hii>hest reported for any cetaccdii. The determination of the physio- logical properties of the blood of large cetaceans has been contined primarily to animals that are stranded or have been dead for many hours before blood samples can be drawn. Lenfant (1964) has summarized most of the data available on marine mammals. The capture and maintenance of Gigi. a California gray whale. E\ch- richliiis rohiistiis. has given us the opportunity, for the first time, to study a large cetacean under definable con- ditions and to determine its blood volume and oxygen-hemoglobin dis- sociation curves. METHODS On two separate occasions the whale was given lO/jCi of radioiodin- Buth William G. Giliiiartin and George A. Antunelis, Jr. are with the Naval Undersea Center Bio-Svstenis Program, San Di- ego, "CA 92132. Richard W. Pierce is with the Coastal Ma- rine Laboratory, Division of Natural Science, University of California. Santa Cruz, CA 95060. ated human serum albumin (Risa)'. The labeled compound was adminis- tered to the animal in one of the brachial vessels in the right pectoral tin. Two blood specimens were taken following each determination to insure that mixing was complete and the albumin was not being eliminated rapidly from the serum. In the first test (27 December 197 1 1 blood vol- ume determination samples were taken at 14 and 20 minute intervals and in the second test (6 March 1972) were collected at 10 and IX minute intervals after administration of (he labeled compound. The blood samples re- moved tor counting were taken from one oi the brachial vessels of the left pectoral lin and put into well-hepann- ized tubes. Three ml of the heparinized whole hlood was added to .^ ml of I ' Abbott Laboratories, Chicago, Illinois. Use of trade names in this publication does not imply endorsement of commercial products by the National fvlanne Fisheries Service. 28 Figure 1. — Oxyhemoglobin dissociation curves for three cetaceans [T. gilti. G. scammoni, E. robustus). All curves have been corrected for pH — 7.4 and determined at 37~C. percent acetic acid to iyse the red cells to permit counting of a uniform suspension without the problems as- sociated with cells settling while being counted. A standard solution was pre- pared by adding a fraction of a milliliter of the same solution injected into the animal to saline in a total volume of 1 liter. The standard was prepared for counting by the same procedure as the blood specimens. All samples were counted for 100 minutes in a 3-inch well Til crystal attached to a Packard Model 2001 Spectrometer Sealer-timer. Counts of the paired blood specimens were very close, within 5 percent in December and 3 percent in March. The reported blood volumes are the mean values of the respective paired samples. The oxyhemoglobin dissociation curve was determined on 21 January 1972. A 20 ml blood sample was secured from a puncture of a distal brachial vein the the pectoral hn. The blood was immediately placed into well-heparin- ized (250 units heparin per 10 ml blood) plastic test tubes, inverted 4 or 5 times, and then placed in an ice bath. Less than 4 hours after collection the dissociation curve was completed by a Dissociation Curve Analyzer (DCA-1. Radiometer, Copenhagen). Duvelleroy et al. (1970) have ex- plained in detail the methodologs in- volved in the operation and construc- tion of the 02-Hb dissociation curves by the DCA-1. Slight changes in pH were monitored for every point on the dissociation curve. Because Pqo changes with pH variation, corrections were made to a pH of 7.4 with the equation AlogPp^ ApH Bohr effect. The value for the Bohr effect was obtained from Lenfant ( 1969). The hematocrit (Hct) was obtained in the usual manner. A Clay-Adams Autocrit Centrifuge was the instrument used. RESULTS The hematocrit, blood volume, and Pjo of the E. robitsius as well as cer- tain physiological blood parameters of other cetaceans are presented in Table 1. The blood volume was deter- mined on two occasions and the oxy- gen binding capacity was determined with one blood sample. Typical sig- moid Oo-Hb dissociation curves are shown in Figure 1. Curves for two other cetaceans. Glohicephalci scani- luoni and Tiirsiops i;illi, determined by the same methods (Antonelis. 1972)-' are included. DISCUSSION The hematocrit of Gigi is not un- like that measured in other mammals. While Lenfant (1969) asserts that this is true for all marine mammals. Ridg- way and Johnston (1966). Horvath et al. (1968). and Ridgway et al. (1970), have demonstrated an increased packed cell volume in some of the small cetacea. Lenfant (1969) attributes such results to differences in technique or in physical condition. However, the animals who showed high hemat- ocrits were maintained in captivity. Had they followed the normal pat- ^ Antonelis, G A. 1972 Oj-Hb dissociation curves of the pilot whale. Globicephala scam- mom, and Pacific bottlenose porpoise, Tursiops gilti- (Unpubl manuscr,} tern of captive animals, the values would have been even higher if sampled in their natural environment. It has been amply demonstrated that animals brought into a captive situation soon show a reduction in both hetnatocrit and hemoglobin content (Gilmartin and Ridgway, 1969,^* Lenfant, 1969). The first blood volume for a large cetacean using isotopic methods is reported. Although H^i labeled hu- man serum albumin was used in the analysis, the similarity of the paired blood specimens taken at each test date indicates not only that mixing was complete, but also that this foreign protein was not being eliminated so rapidly that a meaningful blood vol- ume determination could not be made. Unpublished data on the killer whale are included also. Both animals have blood volumes (£. rohusuis: 6.1 and 8.1 percent; O. onu: 8.2 percent) within the range reported for other species of large cetaceans; Laurie (1933) reported a large blue whale's blood volume as 6.6 percent. Smith and Pace (1971) estimate that the blood and body fluids of large ceta- ceans to be between 10 and 15 percent of the body mass. Lawson { 1962) and Sjiistrand ( 1953, 1962) have reviewed the many factors which affect blood volume and one should be aware of them when evaluat- ing blood volume data. Since the animal is placed under highly stressful conditions as well as the imposition of unaccustomed gravitational forces as a result of removal from the water, the picture for marine mammals is complicated. Nutrition and electrolyte balance also affect blood volume. To our knowledge neither the freezing point depression nor the osmolality of the urine were determined. Osmolality can be calculated, however, using the formulas of Wolf (1958). Gigi's ex- clusive squid diet must have produced a urine whose minimum osmotic con- 3 Gilmartin, W G, and S H Ridgway 1969 Some physiological properties of the blood of the killer whale, Orcinus orca- (Unpubl, manuscr ) 29 _C0 O D) 3 CL - o c _ O 3 nr m o E^ O >.^ T3 5 E ' rtJ O : do ■ TO ^ > o =r ' E in en >fi o o (b o o> C-5 (D 1- cg tt o) '- CO en ^ CM en E ' P o CNj -a- ^ ^ -^j- en CO en O O r^ r- C\J O CT> O CO m vD ■<- ■^ Tt Tt eo ■-- CO 00 m in -^ r- en in in »- c\j m oj x: T3 5-5 S 5 E S a c 05 Q. C 3 o c E £ E 5 o m O Q — o TO C o — £ ■? (I) g nr to 1^ TO £ 5 CO O) > E o ^ III; c 5 ii o - 5^ ; ccntration was 1.670 milliOsniols/ liter. The effect of such a diet, which is isoosmotic with sea water, is un- known. The P50, the partial pressure (mm Hg) of oxygen at which hemoglobin is 50 percent saturated, is a measure of the blood's affinity for oxygen — the higher the P-m. the lower the affinity. The P50 for Gigi was 36.5 mm Hg and is the highest reported for any cetacean. In a list of fifty mammalian species in which the ^50 has been deter- mined, only four animals exhibited a higher P50 (Bartels, 1971). Horvath et al. (1968) compared the dissociation curves of several small cetacea and found that a shift to the left, or increased affinity for oxygen, relates to individual species behavior and feeding habits. Apparently this pattern does not hold for the larger cetaceans. In looking at such parameters as hematocrit, oxygen capacity, and par- ticularly the P^o- a pattern emerges and one is tempted to ascribe this to some behavioral characteristic of the animal. However, one should proceed with caution. Oxygen dissociation curves are de- termined by several methods. The method used by Horvath et al. ( l'^^68) was to treat the blood with varying levels of oxygen and sufficient CO2 to maintain a pH of 7.4. I, enfant ( 1969) and .Schmidt-Neilsen and Larimer (1958) maintained a PcO'? '^'f -*•' rnm Hg in determination of their curves. ■Schmidt-Neilsen and Larimer (1958) observed that In terrestrial animals the blood of the larger animals has the higher affinity for oxygen (low P.w). Lenfant (1969) pointed out that this does not hold for marine mammals and the calculated Pcm's using their formula supports this. .Steen (1971) has pointed out that a Pco2 ''' "^0 "I'll Hg may not repre- sent the true arterial Pcoo '-^^ ^^'^ animal, e.g., a cat is about 28 mm Hg. .Since the ^002 ^^as a profound effect on the Pm and the magnitude of the Bohr shift, one is hard put to make meanlnglul comparisons in marine 30 mammals when different methods arc used. To compMcate the picture fur- ther, Riggs (I'JftO). using a buffered system at a pH of 7.4. observed that animals of varying size had identical Pso's at that pH. In order to make meaningful evalu- ations of the dissociation curves in marine mammals, the in vivo ^002 and pH need to be determined. Rieu and Hamar (1968) point out the dif- ficulties of drawing a representative arterial blood sample although these arterial data have been collected from one species. Tiirsiops iruncalus, by Ridgway (1968). In short, more work needs to be done. ACKNOWLEDGMENTS We thank k. Suwa and E. Wahren- brock of the Anesthesia Department. University Hospital, San Diego, Cali- fornia, for making the Dissociation Curve Analyzer available for our use. and the staff of .Sea World for their cooperation. This study was supported in parts by grants from the Oceanography Section of the National Science Foun- dation (Grant #GA-3I297) and the Bureau of Medicine (Project #MF- 12524014). Ridgway, S. H. 1968. The botllcniise dolphin in biomedical research. In W. I. Guy (editor). Methods of animal experimenta- tion. Vol. .^. p. 387-446. Academic Press, New York. Ridgway, S, H,, and D, G. Johnston. 1966. Blood oxygen and ecology of porpoises of ihree genera. Science (Wash., D.C.) 15I:456-4.S8. Ridgwav, S. H., J. G. Simpson, G. S. Patton. and W. G. Gilmartin. 1970. Hemato- logic findings in certain small cetaceans. J. Am. Vet. Med. Assoc. l.';7:S66-575. Rieu, M„ and M. Hamar. 1968. Prelimi- nary results concerning the gas oT arterial and veinous blood in Dcli'luiui.\ dclphu and Sli'iR'llu .vma. Report for ONR, Contract NF6 10527 l)006.V Riggs, A. 1960. The nature and significance of the Bohr effect in mammalian hemo- globins. J. Gen. Physiol. 43:7,37-752. Schmidt-Neilsen, K... and J. L. Larimer. 1958. Oxygen dissociation curves of mammalian blood in relation to body size. Am. J. Physiol. 195:424-428. Sjostrand, T. 1953. Volume and distribu- tion of blood and their significance in regulating the circulation. Phvsiol. Rev. 33:202-228. . 1962. Blood volume. In W. F. Hamilton (editor). Handbook of physiol- ogy. Circulation. Sect. 2, Vol. 1, p. 51-62. Am. Phvsiol. Soc, Wash., D.C. Smith. A. H.. and N. Pace. 1971. Differ- ential component and organ size rela- tionships among whales. Environ. Physiol. 1:122-136. Sleen, J. B. 1971. Comparative physiology of respiratory mechanisms. Academic Press, Lond.. p. 109.112. Wolf, A. V. 1958. Thirst - physiology of the urge to drink and problems of water lack. Charles C. Thomas, Springfield, p. 344-355. MFR Paper 1052. From Marine Fisheries Review, Vol. 36, No. 4. April 1974. Copies of this paper. In limited numbers, are available from D83. Tec finical Information Division, Environmental Science Information Center, NOAA. Washington. DC 20235. MFR PAPER 1053 Feeding of a Captive Gray Whale, Eschrichtius robustus G. CARLETON RAY and WILLIAM E. SCHEVILL LITERATURE CITED Bartels, H. 1971. Blood oxygen dissocia- tion curves: mammals. In P. L. Altman and D. S. Dittmer (editors). Respiration and circulation, p. 196-197. Biological Handbook. Fed. Am. Soc. Exp. Biol., Bcthescda. Bernharl. F. W., and L. Skeggs. 1943. The iron content of crystalline human hemo- globin. J. Biol. Chem. 147: 19-22. Duvelleroy, M. A., R. G. Buckles, S. Rosen- kaimer. C Tung, and M. B. I. aver. 1970. An oxyhemoglobin dissociation analyzer. J. Appl. Phvsiol. 28:227-233. Horvalh. S. M.. H. Chiodi. S. H. Ridgway. and S. Azar, Jr. 1968. Respiratory and electrophoretic characteristics of hemo- globin of porpoises and sea lion. Comp. Biochem. Physiol. 24: 1027-1033. Laurie. A. H. 1933. Some aspects of res- piratKtn in blue and fin whales. Discov- ery Rep. 7:363-406. Lawson. H. C. 1962. The volume of blood — a critical examination of methods for its measurement. In W. F. Hamilton (editor). Handbook of phvsiologv. Circu- lation. Sect. 2, Vol. 1, p. 23-49. Am. Physiol.Soc, Wash., D.C. Lenfant, C. 1969. Physiological properties of blood. In H. T. Andersen (editor). The biology of marine mammals, p. 95- 116. Academic Press. New York. ABSTRACT Ihc fcc'diiii; of 11 captive yi'iirlini.; ft'iiuilc Eschrichtius robustus wirs oliscrvcd wliilc (II villi; with Iwr «.v well as from llw surface. Slie sucked food off the lioliom wliile \wiinniiiii; lipped over ahinil 120" so ilnil her c /uiA Ui/\ nearly parallel to the lioUoni. .An increase in inoulli viiluine is apparently caused by action of llie toni;ue, resulliui; in sironi; suction, dnriny; wliich ilie lower lip is opened and food enters tlie inoiit/i. How food is separated from water and mud or detritus is not l^nown. Tlie idiserved f>eluivior is protial^ly natural and illuminates earlier records oj sionnuli cinuents. e.\teriuil inarl\iiis;s. and asyninielrii id haleeii. Clearly, iniuli needs to he learned ahout tlie niecluuiisin of feeding; of hideeii wluiles. I'liis species' feediiii; liahits nitiy he unic/ue anioiii; tliein. INTRODUCTION Observations on the food of Escli- rielitius rohustus (Lilljeborg, 1861), the gray whale, have, been summar- ized by Zimushko and Lenskaya ( 1970) and Rice and Wolman ( 1 97 1 ), indicat- ing that the diet consists predom- inantly of benthic animals, moslK am- phipods and a few other crustaceans; incidental items include polychaete worm tubes, shells, gastropod opercula, feathers, kelp, bits of wood. sand, mud. and gravel. Tomilin (19.^7, p. -346-347) suueests that Eschrichtius r o o o ~ 0) o a * ° 0) z ._■ o B E 2S o S 32 G. Carleton Ray is with The Johns Hopkins Univenity, Bal- timore, MD 21205. His" work was partly supported by con- tracts to the University from the Office of Naval Research (Oce- anic Biologv). contract Nonr N00014-67-A-0I63-0010 03. William E. Schevill is with the Museum of Comparative Zool- ogy, Harvard University, and the Woods Hole Oceanographic Institution, Woods Hole, MA 02543. This is Contribution No. 3069 from the Woods Hole Oceanographic Institution. His work was partly supported by the Office of Naval Research (Oceanic Biologv), contract Nonr N00014-66-()241. is to some extent vegetarian (which would make it a most exceptional cetacean), supposing that seaweed found in the stomach is food and not merely incidentally swallowed. Howell and Huey (1930) found the planktonic Eiiplnuisiii pacificu in the baleen of a gray whale taken off northern Cali- fornia on 21 July 1926. Gilmore (1961. p. 11) gives a winter observa- tion of presumed feeding by gray whales, '"criss-crossing thru a dense school of small fish, like anchovies, off San Diego," and Ken Balcomb (pers. comm.) informs us that a gray whale beached 15 miles north of Grays Harbor. Wash., in April, had a gullet packed with several gallons of OsnuTus nionla.x (rainbow smelt). It would appear that EsclvicltiiKs is not limited to eating small benthic crustaceans, but will also eat a variety of other food as opportunity offers. Gray whales seem to do most of their feeding in the Bering and Chukchi Seas (Pike. 1962, p. 831-8.32). Rice and Wolman (1971. p. 24-2,S) conclude that all organisms found in the stomachs of gray whales killed on the Arctic summer grounds are "infaunal benthic species." They state that 95 percent of the food species found in one Bering Sea sample were gammaridean aniphipods 6 to 25 mm long, and that the predominant spe- cies from this sample, Anipdiscu iiuicroi cplnild. "occurs mainly en sandy bottoms at depths of 5 to 300 meters" (italics oursl. Zimushko and Lenskaya (1970) say that gray whales feed on nectobenthos. some 70 spe- cies in all. but that only six species of amphipods are of primary importance. We assume that though such active creatures as amphipods may be in- faunal at times, their well-known ten- dency, when disturbed, to move just off the bottom, would make them readily available to a sweeping whale. One of us (Ray) observed this amphi- pod behavior from a submersible in the Bering Sea in 1972. Nemoto ( 1959) has discussed probable feeding behavior of whales in the light of mouth shape and baleen characteris- tics. During the last century many authors have alluded to gray whales surfacing with mud visible on the beak or other dorso-lateral parts. Pike (1962. p. 823) cites a particularly illuminating communication from Dr. F. H. Fay, who mentions a gray whale supposed to be feeding in 5 fathoms: "As this whale surfaced close to the vessel, mud was seen washing from its back." Although Tomilin (1957. p. 347) supposes that these whales may actually dig their mouths into the bottom, scooping and plowing, it seems to us (see below) that their behavior and anatomy are better adapted to sweeping the bottom than for digging; this accords well with the evidence of asymmetrical barnacle infestation and baleen wear reported by Kasuya and Rice ( 1970). The gray whale calf. Gigi, which was captured in March 197 1 and kept by Sea World. San Diego, was initially fed an artilicial diet, but was soon taught to eat full-grown squid. Lolii^o npulesccns. By the time of our observations (28 January- 1 February and 1 1 March 1972). her daily diet was 900 kg of squid, dropped frozen into her tank in 9 kg blocks, and her weight gain was almost 40 kg a day. Our behavioral observations were made both from the water's surface and by scuba-diving with Gigi. We also used underwater motion pictures made h\ John .Seeker of Sea World when Gigi was about 6 months old. To aid in our interpretation, we have consulted her trainers (Bud Donahoo and Susan Bailey), and we have solicit- ed observations on Gigi and on other gray whales from several of our col- leagues. To them, who are mentioned below, to the Naval Undersea Center, and to the management of Sea World, we are grateful. BEHAVIORAL OBSERVATIONS Before detailing our observations, we remind the reader that a gray whale's head is roughly triangular in cross section, the gular region being the base while the cheeks form the sides, sloping inwards at about 60° towards the narrow beak-like upper jaw. The curved mouth is at about the middle of the cheeks. The mouth has effectively only lower lips; the upper lips are represented by the rabbet-like recess above the gum line into which the lower lips fit snugly. In the course of teaching Gigi to eat squid, trainers Donahoo and Bai- ley taught her to relax the edge of the left lower lip and turn it outward in response to light taps on the head. Food was placed by hand in the open- ing thus created, passing into the throat either through or under the baleen. This was in contrast to the feeding of the artificial liquid diet, when the jaws were opened while accepting the feeding tube; during the hand-feeding of squid, the jaws re- mained closed and the lip was opened. as was also the case later on when one of us thrust an arm down her pharynx. Training Gigi to move her lip volun- tarily was critical, for normally the lip was held so tightly shut that a man could not forcibly pry it open. This training was done while she was grounded in the tank almost empty of water; it was not long before she would thus accept food while swim- ming. Soon thereafter she was feeding freely without the aid of her trainers. Gigi was always fed from the left side (Donahoo has mentioned having been i2> 34 o 5 * in n 3 — a o 35 o n |« 0) ■ tg n 36 a horsLMiian before hecoming acquaint- ed with whales), which may account tor the left-sided sweeping behavior described below; Kasuya and Rice (1970) reported that of 34 gray whales that they investigated, 3 1 were right-sided. We observed that the edges of the lips could be turned out and down through about 60°, either one or both sides at a time. Motion pictures further show a fluttering of the pos- terior part of this edge during hand- feeding, especially near the major flexure. Voluntar\ feeding was as follows: The frozen blocks of squid floated at the surface and, as they thawed, the squid mostly sank slowly to the bottom. Gigi often "nibbled"' at the thawing corners of the blocks, using the left side of her mouth and usually, but not always, holding the block at about the place where the fluttering had been noted. The nibbling was oc- casionally accompanied by a noisy pulsation called "earthquaking" by the trainers, and splashing or jetting of water and air for nearly half a meter (Figures 1 and 2). The jet was usually at this same place near the after end of the mouth, but it sometimes ran nearly the entire length of the baleen (not quite to the forward end of the mouth). Often the jetting was on both sides of the mouth. When Gigi's mouth was at the surface, air was involved in the jetting, but not always when her mouth was completely submerged, and not at all when she was on the bottom of the tank. We assume that this air was adventitiously taken in. as in eating soup. After most of the squid had fallen to the bottom of the tank. Gigi's be- havior altered markedly. As she ap- proached them, she would roll over toward her back some 120°, so that her cheek was nearly parallel to the bottom and about 10-20 cm above it. As she swam over the squid, she left a clean swath 30-50 cm wide. It was apparent that the squid were being sucked up in a sort of pulsation, as some squid briefly reappeared after their first disappearance into her mouth. It is presumed that she could easily see the squid lying in her path. In the cylindrical tank she described a track slightly dorsad of straight ahead, so that she swept over the squid at about a 30° angle to the mouth (Figures 3 and 4). Then three separate actions were seen: ( 1 ) an opening of the edge of the mid to posterior part of the left lip so as to fold it away from the baleen. (2) a swelling of the gular region and expansion of the gular grooves (Figure 4). and (3) an opening of the right side of the mouth, during which squid were sometimes jetted out. The third item may merely mean that it is easier to open both sides of the mouth symmetrically, though Gigi had showed us that she could flex her lips one side at a time. Since we could not see all these parts of the whale at once, we can only infer the presumable sequence of these re- lated events. Then Gigi righted herself and swam away; sometimes turbid jets could be seen pulsing from both sides of her mouth. ANATOMICAL INTERPRETATION Our understanding of the mecha- nisms involved is hampered by our ignorance of the myology and other soft anatomy of this species. We have been able to find only osteological anatomical descriptions and have had no carcass available for even rough dissection. W. C. Cummings and J. Sweeney made, on our account, some exploratory sections of the lower lips of dead neonates found on the beaches of Laguna Ojo de Liebre, Baja Cali- fornia, and found them to be well muscled. D. W. Rice reminds us that the tongue is also well muscled, much more so than in Btilucnopicni; it is well figured and described by Andrews (1914, p. 254. pi. 2 1. fig. 4. and pi. 22, fig. 6). All this, as well as observations of behavior, strongly indicates that the gray whale's oral anatomy is adapted for suction and thai motion of the lips is voluntary. We had but limited opportunity to manipulate Gigi's mouth ourselves; one of us (Schevill) had his arm in her mouth several times while she was "earthquaking" and could feel no motion at all of the tongue and only a slight agitation near the larynx. But W. E. Evans (in litt.) states that "the tongue cannot be pulled back and forth very easily; however, it can be raised high, dis- placing a reasonably good percentage of the volume of the mouth cavity". Donahoo had his hand in Gigi's mouth repeatedly; both he and Evans have emphasized the tongue's strength and mobility. Donahoo asserts that it moves so as virtually to vacate the oral cavity and that this involves a shape change. He further asserts that the shape change travels rearward and that this movement of the "ball" of the tongue can be seen from outside, as the gular grooves expand. This posteriorly moving expansion of the gular region was also seen by one of us (Ray) underwater. Further, Dona- hoo said that as the tongue moves back, a strong inflow appears at the out- folded lip. He added that Gigis feeding was not simply accepting, but quite selective. When presented a mixture of squid, "Pacific mackerel " (chub mackerel, Scomhcr juponiciis). and "whitebait" (probably jacksmelt. Atlu'iinopsi\ culiforiiiciisis. or top- smelt. Alhcrinops affinis). all three were sucked from the bottom, but only squid were retained, the others being rejected. CONCLUSIONS Nothing benthic of the size of squid has been reported in the diet of Eschiichlius. so we should be cautious in interpreting this captive's feeding style as indicative of natural behavior of the species, bearing in mind that Gigi was completely isolated from her kind throughout captivity. Neverthe- less, her bottom-sweeping habit we suppose may be natural, since it ap- pears appropriate for catching the animals that comprise the recorded 37 natural food of this species of whale. Our captive's habit of sweeping a few centimeters off the smooth tank bot- tom does not deny the probabilits that sweeping a soft or irregular bottom at sea could get mud on the sweeper's back (cf. Fay in Pike, 1962. p. 823), especially if the prey is actually benthic. Cetological literature is full of poor- ly supported conjecture, and we hesi- tate to add more. Although we have learned a number of things from the captive Gigi, there is still much un- known. For one thing, her jetting water in pulses from a particular re- stricted part of her mouth seems to imply, perhaps, a special activity of the tongue. Furthermore, we do not understand the mechanics of the hy- draulics that bring the food-bearing water into the mouth. This is no mys- tery in whales that swim along with the mouth wide open, but it is not so obvious in a whale which swims along rather slowly with only a narrow slit open, as did our Esclirichiius. Here it seems necessary to increase the volume of the mouth to cause useful inflow of water. We are handicapped by our imperfect understanding of the func- tions of the muscular tongue. W. E. Evans (pers. comm.) has told us that Gigi's tongue once pressed his hand painfully hard against her palate. Such pressure might serve to push the gular region downward, enlarging the mouth cavity, and this idea fits with the ob- servations of Donahoo and Ray of the migrating tongue-bulge visible from beneath. Thus we suppose, from the assorted evidence, the following concatenation of events in feeding; First the whale rolls over far enough so that the cheek is about parallel with the bottom, and the lip is opened as the tongue, press- ing against the palate, pushes the gular region away so that it expands, pro- ducing an inflow which brings in the epibenthic food. Then the tongue rcla.xes and the gular musculature tightens, reducing the size of the mouth cavity and expelling water; the food IS trapped in the baleen fringes. We do not know exactl> what happens next; perhaps a slight re- newed suction of water removes the food from the baleen fringes, and swallowing presumably follows. LITERATURE CITED Andrews. R. C. 1^*14, Monographs of the Pacific cetacea. I. The California gray whale {RInuhtanccU's tiUmcita Cope). Mem. Am. Mus. Nat. Hist. (New Series) 1:2:7-287. Gilmore, R. M. 1961. The story of the gray whale. 2ncJ ed. Privately published. San Diego. 17 p. Howell, A. B., and L. M. Huey. 1930. Food of the gray and other whales. J. Mammal. 11:321-322. Kasuya, T., and D. W. Rice. 1970. Notes on baleen plates and on arrangement of parasitic barnacles of gray whale. Sci. Rep. Whales Res. Inst. 22:39-43. Nemoto, T. 19?9. Food of baleen whales with reference to whale movements. Sci. Rep. Whales Res. Inst. 14: 149-290. Pike. G. C. 1962. Migration and feeding of the gray whale {E.\chruhiiiis nihhusiis). J. Fish. Res. Board Can. 19:815-838. Rice. D. W., and A. A. Wolman. 1971. The life history and ecology of the gray whale (E.schnchtius nihusius). Am. Soc. Mammal.. Spec. Publ. No. 3. 142 p., 18 tables. 38 text figs. Tomilin, A. G. 1957. Kitoobraznye. Zveri SSSR i prilezhashchikh stran (Cetacea. Mammals of the USSR and adjacent coun- tries.) 9. 756 p. (Engl, transl. Smithson. Inst., 1967.9,717 p.) Zimushko. V. V., and S. A. Lenskaya. 1970. O pitanii serogo kila (Eschrichinis gib- hosiis Erx.) na mestakh nagula (Feeding of the gray whale [E.schnclunis nihhosiis Erx.) at foraging grounds). Fkologiya Akad. Nauk SSSR l(3):26-35. (Engl, transl.. Consultants Bureau. Plenum Publ. Corp., 1971. Fkologiya 1(3):205-212.) MFR Paper 1053. From Marine Fisheries Review, Vol. 36, No. 4, April 1974. Copies of this paper, in limited numbers, are available from D83. Technical Information Division. Environmental Science Information Center. NCAA. Washington. DC 20235. MFR PAPER 1054 Sounds Produced by the Gray Whale, Eschrichtius robustus JAMES F. FISH, JAMES L SUMICH, antj GEORGE L. LINGLE ABSTRACT U ndcrwawr \iiuihIs pnuliKcil hy a yniiiii; cupiivc yn/y uluilc arc described. A "iucudUc-\t>it}idiiii> pulsed signal." consisliiiii of H lo 14 pulses in hursts Uisliui; up Id 2 sec was the niosl c<>nuiu>n vocalization. Other souitds included a low- frequency "i;ro\\l" or "moan." similar lo a sound recorded from L;ray w/iales at sea: a short, hroiulhand. "i;riinllike" sound: a low-piit hed "hlowluile rumble": aiul a loui; "ntctaUic-souiuliui; pulse train" tlial meiiicd into a low-frequency "Kroan." The sounds ctnild not be correlaled with specific behaviors. Also de- scribed are "clicks" recorded in the presence of the whale wlien site was returned to \ea ami similar "iliiks" recorded from i;ray whales in liii kaninnish Bay. I'ancoin er Island. Caitoila. This report describes a variets of sounds recorded from Gigi, a young gray whale. Eschrichtius robustus. while she was in captivity at Sea World, a marine park in San Diego, Calif., and sounds recorded in the vicinits of the whale when she was returned to the ocean nearly a year later. Also described are the sounds recorded in the presence of gray whales in Wickaninnish Bay, Van- couver Island. Canada. 38 Table 1. — Summary o( previously published data on gray whale sounds. Eberhardt & Evans. 1962 Painter. 1963 iWenz. 1964 Rasmussen & Head. 1965 2Gales. 1966 Hubbs, 1966 Asa-Donan & Perkins. 1967 Cummings et al , 1968 Poulter. 1968 Pulse Repetition Pulse Peak Duration Frequency Pulses per rate duration energy Signal type (sec) (Hz) burst (per sec) (msec) (Hz) "Croaker-hke 40-700 80-300 grunts" ■Low-frequency 40-700 80-300 rumbles ' "Pulses" 4-6 100 "Low-pitched 4-9 pulses Approx 33 11 grunting" per grunt "Clicks" <200->3.000 10 No sounds "Clicks- <200->3,000 10 No sounds "Ectiolocation- 70-3.000 5-22 3-7 1-15 400-800 like pulses" "Variable whistles" "Moans" 1 5 20-200 "Underwater Approx. 1 15-175 <1C0 blow" "Bubble-type 0 7 15-305 sounds" "Knocks" to 350 "Croak-like grunts" "Rumbles" "Cries" "Grunting" "Rasping" 1 to several "Pulses" 5-18 "Chirps" 2-5 8 "Bong" "Clicks" to 12,000 3-5 '■- Both references show data on sounds recorded by Asa-Donan in 1955 Vocalizations have been recorded from migrating gray wiiales off the southern California coast (Wenz, 1964. and Gales. 1966. both reporting on recordings made by P. V. Asa-Dorian in 1955; Asa-Dorian and Perkins. 1967: Cummings. Thompson, and Cook. 196S) and from gray whales in the lagoons of Baja California. Mexico, where the whales breed (Eberhardt and Evans. 1962; Painter. 1963; Poulter. 1968). Unsuccessful attempts to obtain sounds from gray whales off southern California and in the lagoons have been made by Rasmussen and Head (1965) and by Hubbs (1966). The published data on gray whale sounds are summarized here in Table 1 . Gigi had already been in captivity at Sea World and hand-fed by her trainer for about 2 months before the tank recordings were made. Although she seemed quite content in her un- natural surroundings, her behavior was certainly not representative of a free-ranging gray whale of the same age. Hence, the sounds may or may not be similar to sounds emitted by a young gra\ whale in its natural en- vironment. A second problem with any tank recording is the effect of tank resonance and reverberation on the physical characteristics of the sounds. Certain frequencies were probably accentuated in amplitude and extended in time. Nevertheless, the data at least represent the general James F. Fish is with the Naval Undersea Center, San Diego, CA 92132. James L. Sumich is with Grossmont College, El Cajon, CA 92020. George L. Lingle is with SEACO, Inc. al the Naval Undersea Center, San Diego, CA 92132. frequency range and variety of a young captive gray whales sound emissions. SOUNDS OF GIGI AT SEA WORLD Sounds were recorded simultane- ously in water and in air on a 2-track tape recorder (Uher 4200)' at 19 cm/sec. The hydrophone (Wilcoxon M-H90-A). connnected to one chan- nel of the recorder, was suspended 1 m above the bottom of the circular concrete tank (11 m wide X 4 m deep). The frequency response of the underwater recording system was 40 Hz to 16 kHz. ±.^ dB. The micro- phone, connected to the other channel. was lowered over the lip of the tank ' Use of trade names in this publication does not imply endorsement of commercial products by the National Marine Fisheries Service. 39 ap 13A31 3Aii\n3a i A>. .^ '«' :A ilK 1 uii ^ iu ^. , (, ^ . u il. i ij ^A. 1 ill ap -\3H31 3AllV13a J* \' ap '13A31 3Ali\n3i) (Qi zHi AONSnOaaj I 1 I I ■ 1-' O O O O ^ » -i <>i - ° ZH>1 A3N3n03dJ ..'.'*1 4 "O CO = < ^ 0 a a oil . » c Q a - * c ?|S ON* «Z « - ^ "O i"i li! s s ° ogf ■ °-S > = Siu = "Si, « O 0) g ■» ^ •" - 3o 5" O" S -S w £*?£ 1 Eo o 51 S « -^ o t o * = « = =i§~ 5 2 »< • a. ». = s ^s * = £ o CD CM .■?:£ -_ •E so i>.S.£ 2 ■■TJ E £ = o k « . 0) o > E a : 51 £• a.- "I £ J: ap "I3A31 3AliV13d ap 13A31 3AUW13U §= * <:' i g »■- i 3 2 i? * 0) a> rf T O) > o — « o - ? o •= E " .^S S E 1 ■ '^ M li>l .it*. bJ (W) I! 'H>l ADN3n03dd • E *-o — (0 a - ' ±: (0 -o — » ■ 2 uj « H 3 "5 a J? Q- £ 3 Q. <0 •Oct.* •n c o « c6 - * « =o « — 2 - c — O 0» ■ -.A. 1 ; .: V . '*!* • ir. ^ , r.. - v: 1 - - . . — ■• ' 'f^ ■At ^^ m. * J) -'! -4 4 1 is- ^ ^ o o > . *" * o2 a = I o OT> = o £ o tM -O Q 3 0> ■ o C Ul ^ N ■ • C m (0 a F o Q. >> 10 o «) u £- 0) o> « E o ■o rn b ? r> o T o (B to determine if these sounds, which were unlike any recorded from Gigi at Sea World, actually came from the whale or from another un- seen biological source in the area, we now believe they were emitted by Gigi. The clicks were nearly identical to the clicks we have recently recorded in the presence of gra\ whales in Wick- aninnish Bay, Vancouver Island. Can- ada. The clicks recorded in the presence of Gigi are shown in Figure 2. Their principal energy occupied a band from about 2 to 6 kHz, centered at 3.4 to 4.0 kHz. Click duration was I to 2 msec. Eight minutes and 15 sec after the whale entered the water most boats in the area shut down their engines for our recording. The first burst of 29 clicks was recorded 6 sec later. Three minutes and 49 sec later the boats started their engines and we had to terminate our final recording of Gigi. During the 3 min and 55 sec of quiet-ship conditions we recorded 1.304 clicks. The number of clicks per burst (or train) varied from I to 833 and the click repetition rate from 9.5 to 36.0/sec. The longest click train, containing 833 clicks at an average repetition rate of 19/sec. began about 1 min after the boats had shut down their engines. Although the amplitude of the signals varied with time, we could not correlate signal level with the location of Gigi because the animal was not seen dur- ing the entire time of the recording. SOUNDS RECORDED FROM GRAY WHALES OFF VANCOUVER ISLAND The system used to record sounds in the presence of gray whales in Wickaninnish Bay on the west coast of Vancouver Island, Canada, con- sisted of a cassette recorder (Sony Model TC-126) and a portable under- water listening set (InterOcean Model 9()A Bio-Acustik). The useable fre- quency range of the system was 100 Hz to 10 kHz. The hydrophone ar- rangement shown in Figure 3 resulted in good quality recordings with the small boat system. Since 1967, as many as seven gray whales have been sighted at one time in Wickaninnish Bay. However, all of the recordings described here were from single whales or pairs. At 1725 hr on 10 August 1973. several click trains were recorded from a single feeding gray whale in 10 m of water, 1.200 m friim shore. Ver\ little wind 42 and calm seas made recording condi- tions ideal. The first clicks, shown in Figure 4F, began 1 mm after the whale started a 3-min-J!5-sec-long dive. at a distance of 50 to 70 m from the hydrophone. Additional click trains (Figure 4G) occurred simultaneously with the first exhalation after the dive. Twenty sec later, noise from an unseen boat began and continued for 95 sec. A third click train was emit- ted 50 sec after the boat noises ceased and 50 sec prior to the next blow. By then, the whale was 80 to 100 m from the hydrophone and the received level of the clicks was 5 to 7 dB lower than the level of the clicks recorded when the whale was half that distance from the hydrophone. On 18 August 197.^. the click train shown in Figure 4H was recorded from a single feeding gray whale at 0900 hr. The whale was about 600 m from shore in 4 m of water. The sur- face was calm with about a Im swell. At the time the click train was emitted, the whale v\as 100 to 150 m from the hydrophone. Twenty min later a sin- gle harbor porpoise, Phocoena pho- coena. was observed in the area. About 5 hr of recordings uere made in the presence of the gray whales in Wickaninnish Bay and much additional monitoring was done without recording. Although at times nearly continuous very faint clicking could be heard, only about 250 of the recorded clicks had good signal-to- noise ratios. The number of clicks per train varied from I to 96 with repeti- tion rates of 8 to 40/sec. The principal energy of these clicks occupied a band from about 2 to 6 kHz. centered at 3.5 to 4.0 kHz. The average click duration was a little under 2 msec. DISCUSSION striction (similar to the sound of air' escaping from a scuba regulator un- derwater). Since this whale sound generally was not associated with ex- halation or blowhole movement, if it were, in fact, generated by escaping air. the air must have passed from one internal chamber to another. No bub- bles v\ere observed coming from the mouth or blowholes. Although the possibility exists that another species of marine mammal could have produced the clicks re- corded when Gigi was released off San Diego and the clicks recorded in the presence of gray whales in Wick- aninnish Bay. we think the evidence indicates that the clicks did come from the gray whales. The acoustic param- eters of the clicks recorded from the geographic areas are nearly identical. The only marine mammals, other than gray whales, observed in either recording area was the single Phocoena phocoeiw observed a half hour after the recording was made on 18 August 1973 in Wickaninnish Bay and a small group of Dclphiniis dclphis. about 2 km awa\ from the site of Gigi's release a half hour before she was released. Phocoena phocoena. however, has not been observed off San Diego, and clicks of Delphinits have a much higher frequency content than described in this report. Also, the level of the clicks recorded in the presence of Gigi was too high for the sounds to have come from the Del- phinits as the clicks appeared to origi- nate from a single source rather than from a group of animals. We have no evidence that the clicks recorded in the presence of gray whales have an echolocation function, but if the\ do. their frequency range (2 to 6 kHz) probably would be too low for the sounds to be useful for locating small individual food organ- isms. However, they could be helpful for finding dense concentrations of organisms or for ranging off the bot- tom to feed or navigate. Despite four seasons of recording in the presence of hundreds of migrating gray whales off San Diego, Naval Undersea Center personnel have never recorded similar clicks from the whales. But. accord- ing to most authorities, gray whales do not feed on their long migrations (Rice and Wolman. 1971). If the clicks were associated with feeding, we consequently should not expect to TAPE RECORDER AMPLIFIER CORK FLOATS,^ HYDROPHONE LINE (60 FT LONG) SPAR BUOV (BICYCLE NNER TUBEI BRASS SWIVEL 8" DAMPING DISC - ^CORK FLOAT FOR NEUTRAL BUOYANCY We do not know how any of the sounds discussed in this paper were actually produced by the gray whales. The ""metallic-sounding pulsed signal" produced by Gigi at Sea World sound- ed like air bubbles escaping from an area of high pressure through a con- Fjgure 3. — Hydrophone suspension system used to record underwater sounds in Wickaninnish Bay, Vancouver Island, Canada. 43 1 a> - x iii- O O w « 2 « E - CO £ a 0) C (A k •* - .CD C ) CO u) c u . ■" — u. >, a ffl in M -a j2 Sen? o c .- = 5 ■E.SJ 2 .? a o < » i' » S^o ■ "52 X a a o a c « £ * C Of » u £ a - SI S° o a m " * o> S; o •SOS 11"= = _ „ O (0 .£ c 5! i Of '^ "Is o » o c 5 f- " - » E J3 a. . O *- Dl = o E « E o m ■; ° " na>< ^1 = — ■ 2 ° .2 « i O r; ■= = in Q) * S o tj a " 0 o 5 "• c "> 3 t . S ■ o u a> -c < i3 > -D W 1 « tt> o ai ^ n c 7 j< O * *■ o> « .z: S ■ 3 o * a .E "*^ *- (0 <0 U. O Tl U ^ 8P laABl 3MiV13a zH*i ADNanOadd 13A31 3Alitf13a encounter them in this area of migrat- ing whales. When the clicks were recorded in Wickaninnish Bay, the gray whales were feeding. Why Gigi emitted clicks when released is un- known. In this case, their function could have been orientation since it is unlikely that she was looking for food so soon after being placed in a new environment. The clicks dis- cussed here are only slightly like those recorded by Asa-Dorian in 1955 (see Wenz. 1964). They are not similar to any other reported gray whale sounds. Other recent evidence for mysticetes producing click-type sounds has been reported by Beamish and Mitchell (19711. Their recordings in the pres- ence of blue whales included clicks with peak energy in a band from 2 1 to 3 1 kHz. ACKNOWLEDGMENTS We are grateful to Wilburn G. ("Bud") Donahoo for his help at Sea World during the recording session; to William C. Cummings for his advice and assistance in the recordings of Gigi at sea. and to William E. Evans and Fay Wolfson for their suggestions on the manuscript. This work was supported by the Naval Undersea Center. Independent Research funding, and the Office of Naval Research. Oceanic Biology Branch. Grant No. NR 104-123. LITERATURE CITED Asa-Donan, P. V., and P. J. Perkins. 1967. Ttie controversial production of sound by the California gray whale, Eschricluiiu gihhosus. Nor. Hvalfangst-Tid. (Norwe- gian Whaling Gazette) 56:74-77. Beamish, P., and E. Mitchell. 1971. Ultra- sonic sounds recorded in the presence of a blue whale, Bakwrniplera tnit^cultis. Deep-Sea Res. 18:803-809. Cummings, W. C, P. O. Thompson, and R. Cook. 1968. Underwater sounds of mi- grating gray whales, Eschruhtius kUiucus (Cope). J. Acoust.Soc. Am.44:1278-1281. Eberhardt, R. L., and W. E. Evans. 1962. Sound activity of the California gray whale, Eschrichnu.s glaiiciis. J. Aud. Eng. Soc. 10:324-328. Gales, R. S. 1966. Pickup, analysis, and interpretation of underwater acoustic data. Ill K. S. Norris (editor). Whales, dolphins, and porpoises, p. 435-444. Univ. Calif. Press, Berkeley and Los Angeles. Hubbs, C. L. 1966. Comments. In K. S. Norris (editor). Whales, dolphins, and porpoises, p. 444. Univ. Calif. Press, Berkeley and I os Angeles, Painter, D. W., II. 1963. Ambient noise in a coastal lagoon. J. Acoust. Soc. Am. 35:I458-1459(L). Poulter, T, C. 1968. Vocalization of the gray whales in Laguna Ojo de Liebre (Scammon's Lagoon) Baja California, Mexico. Nor Hvalfangst-Tid. (Norwegian Whaling Gazette) 57:53-62. Rasmussen, R. A., and N. E. Head. 1965. The quiel gray whale ( E.schnchinis glaiicu.s). Deep-Sea Res. 12:869-877. Rice. I). W., and A. A. Wolman. 1971. The life history and ecology of the gray whale {Escliricluiiis robuxius). Spec. Publ. 3. Am. Soc. Mammal., 142 p. Wenz, G. M. 1964. Curious noises and the sonic environment in (he ocean. In W. N. Tavolga (editor). Marine bio- acoustics, p. 101-123. Pergamon Press. New York. MFR Paper 1054. From Marine Fisheries Review, Vol. 36, No. 4, April 1974. Copies of this paper, in limited numbers, are available from D83. Technical Information Division, Environmental Science Information Center, NCAA, Washington. DC 20235. MFR PAPER 1055 Aerial Observations of Migrating Gray Whales, Eschrichtius robustus, off Southern California, 1969-72 J.S. LEATHERWOOD ABSTRACT Miiiratini; iiray hIuiIcs were observed from lielicopler und fi.\ed-\\ini; (linnifl from central Ccdifoniici .soiilh lo Cedros mid Giuididiipe Islunds. Baja California. Me.xico. Willi ihe primary .\ii;/ilini.; effort off southern California. Peak nundiers were observed off soiit/iern California in January for tlie southward iniiiration and in Marcli for tite iiortliward inii;ratioii. Individuals were observed with the same relative frequency 80-160 km offslun-e as they were within 80 km of shore. Cows witli calves were seen from February through May. primarily inshore, and tended lo be alone or with other cou s with calves. Yearling whales were seen insliore from February through April and also tended to be solitcuy or with other yearlings. Average speed of movement for lunthward migrants was 2.8 knilhonr. Results of aerial surveys compare favorably with published summaries of the liming of migration based on sliore and ship samples and support the \'alue oj aerial surveys us u tool in cetacean population studies. INTRODUCTION Since shortly after its population began to recover from a second near- e.xtermination by man in the 1920's and I930's (Gilmore, 1955), the Cali- fornia gray whale, Esclirichtius ro- bustus, has been the subject of more public interest and more scientific research than perhaps any other spe- cies of large whale. Because of their spectacular nature and proximity to shore along much of the route, the migrations of the species have been rather exhaustively described by Scam- mon (1874), Hubbs (1959), Gilmore (1960a and 1960b), Rice (1961), Pike (19621. Hubbs and Hubbs (1967). Adams ( 1968). and Rice and Wolman (1971). Observations from shore sta- tions (primarily at Point Loma in 45 San Diego, and at Yankee Point near Monterey) supplemented with aerial observations and boat surveys, have fixed the timing and described most aspects of that migration in detail. Even so. several interesting gaps still exist in our knowledge of the mi- grating animals. For instance, although Gilmore (1969) has discussed move- ment patterns of yearling whales on the southern migration, there are no reports on the movements of yearlings during the northern migration. Simi- larly, although Hubhs (1959) reported that "cows with calves seem to take a more offshore path." actual data on - _ - I97Zn - 1971^ 19700 - ^ 19S9n - ' - GRAND TOTALS - - 74 FLIGHTS 279.70 HOURS _J — j U 1 1— r-r ^ p-r^ !^^^x^4' JAN FEB MM APR MAY JUN JUL AUG SEP OCT NOV DEC Figure 1. — Flight hours, 1969-72. the movements of mothers with calves after they leave the breeding lagoons are so scant that Rice and Wolman (1971) simpl>' report that '"the route taken by females and calves during the spring migration is unknown." Finally, although average rates of movement for the population have been computed from dates of peak passage at two separate shore stations, there are actual numbers for rates of movement of individual animals to test those averages only for the south- ward migration (W\rick. 1954; Cum- mings, Thompson, and Cook. 1968). Since February of 1969. the author has been conducting routine aerial surveys of the cetaceans off southern California, primarily in the area from lat.34°N south to Islas Todos Santos and offshore as far as 280 km. Additional flights have surveyed the coast from Point Mugu north to Mon- terey Bay in March and the area from San Diego to Cedros and Guada- lupe Islands in January and February. Ill 3^41(UP3 3 1 3^^,„„„ ^-J 2 1 1 2 5lM 4 1 2 1^^ T|?1l 1 1 1 4 911 5 4 2 I'l'jJCEAN 1J2|1 IJ 2^^5 4 5 5 62" '™^ Wlfri 1 !i8 5 4 7 9 9 8 ijzil'l 1 2 2 3 412 62431*^ 142 15 3 2 12 3 I02J3221 1 2 23322533366 y 3!2 2 2 1 1 14 2^ 1 2 1111 1*1-|32' Figure 2. — Survey effort by 10-minute blocks, southern migration, 1 October to 15 February. Each number represents total number of times that area was surveyed during this time period. METHODS Flights were made in Navy H-3 helicopters and S-2 reconnaissance aircraft, and in twin-engine rental air- craft. Survey altitudes ranged from 150 to 300 meters depending on weather conditions. Detailed observa- tions were made from as low as 15 meters. Although gray whales were not the exclusive target of the survey, for every gra\ whale sighting the number and estimated size of indi\id- uals. their location, swimming direc- tion and speed, and details of behav- ior were recorded. Through I July 1972 we made 74 flights totaling 279.7 hours of obser- vation time (Figure 1). Sampling ef- fort was accelerated during March. April. May. and June 1972 in support of the radio track of the gray whale Gigi (Evans. 1972. and this publica- tion) and of a common dolphin. Dcl- pliiiui\ ilclphis. subsequently tagged and radio-tracked from aircraft (Evans and l.eatherwood. 1972). In general, surveys were more extensive during the period of the northern migration (approximaieh mid-February through Mav). J. S. Leafherwood is a member of the staff of the Bio-Systems Program. Naval Undersea Cen- ter, San Diego, CA 92132. To facilitate data analysis, the study area was divided into 10-minute blocks, and tallies were maintained of the number of times each zone was surveyed for cetaceans whether or not animals were sighted. Zones were not recorded as surveyed if cloud cover, fog. or surface water conditions pre- vented adequate observation in the area. I V 1 1 1; T^ r s ^ ^ 1 >rT\ ^ 1 112 2 iVa 1 2 2 2 2 4^ " X 1 1 1 2 6 5 8 11J4 9 5 e"^ 4 r,.». =T 1 2 1 1 1 1 14 4 3 131SiB9 10 7 7^7. i |l r 1 3 5 8 10171210 8 7 OCEAN r2 I'l 1 1 2 1 5 f,\3 4 9 25131414 3, -| 1 l' :i'2 'l 1^4 8101631lt,„ 1 4 4 5 5 6 5!8 4 8 14153139 s« 1 1 1 3 3 3 3^2(4 3 5 5 1015232^ 1 1 2 2 2 3 5 V 2 2 1 2 4 4 3 3 3 2 1 2 3 1 1 1 1 1 - 1 1 1 1 1 1 liiii 1 1 » 1 1 1 1 1 \ 1 12C " 119" HE • 117 Figure 3, — Survey effort by 10-mtnute blocks, northern migration, 16 February to 1 June, Each number represents total number of times that area was surveyed during this period. Figures 2 and 3 summarize the to- tal number of times each zone was surveved during the periods of the southern migration ( I October to 15 February) and northern migration (16 Februar> to I June) of gray whales. Effort was concentrated off San Di- ego during both periods because all three airfields used are located there. The substantial increase of effort in the southern San Pedro Channel from the southern to the northern migra- tion is the result oi the aerial radio- tracking mentioned above. During the three migratory seasons, gray whale groups were sighted 91 times in the stud> area. Of these. 23 groups included mothers with calves, 19 included yearling whales, and 8 sightings represented observations of the same animals on successive davs. 46 RESULTS Migration Peaks and Offshore IVIovements The picture of migration peaks ob- tained from the aerial surveys agrees with the summaries of Hubbs (1459) and Gilmore (1960). The earliest animals were seen in the third week of December and the latest during late May. The largest numbers of animals were seen during the first and second weeks of January and the sec- ond and fourth weeks of March. Be- cause the amount of aerial survey effort varied from month to month, indices of apparent abundance were computed for data in blocks of a month by dividing both the number of aerial observations and the number of individuals seen by the amount of survey effort during that time period. These indices (Figure 4) also clearly indicate the periods of greatest abun- dance off San Diego as January and March. During both legs of the migration many whales were sighted far offshore. (Figure 5) presumably taking what has been called the "inter-island leg" (Gilmore. 1969). For instance, with- in the 64 km wide band between lat. 32°I5'N and 32°55'N. southern mi- grating gray whales were encountered during 4.7 percent of the flights in the first 80 km from shore. 5.0 percent of the flights in the second 80 km. and 1 percent of the flights over the next 48 km. Similarly on the northern migration, grays were sighted 6.4. 9.2, and 3.3 percent respectively of the times the three zones were sur- veyed. These findings support the con- tentions of Rice (1965) and Rice and Wolman (197 1) that at least since 1965 a rather high percentage of the whales have passed offshore, out of sight of Point Loma. Though most of the animals taking the offshore route apparently strike for the coast shortly after they pass bv the southernmost of the Channel 5.0- 4.0 3.0 2.0 1.0 5.38 2.36 TOTAL DBS. 1" TOTAL FLT. HRS. 2.20 1.50 .38 .02 14.0 - TOTAL ANS. 2 "TOTAL FLT. HRS. 12.6 12.0 - 10.0 - 8.0 - 6.1 6.0 — 4.91 4.0 " 2.4 2.0 " .9 1.04 OCT NOV DEC JAN FEB MAR APR IMAY JUN OCT NOV DEC JAN FEB MAR APR MAY JUN Figure 4. — Indices of apparent abundance (Ij) ol gray whales (rom aerial surveys. 1969-72. 34° 33 Figure 5. — Aerial survey gray whale sightings, 1969-72. 32° 1?0° 119° 118° 117° Islands, some do pass offshore toward Guadalupe Island. Gilmore (1955) re- ported Hubbs' sighting of three mothers with calves outside Guadalupe in February of 1950. In February 1972. I located two gray whales on the outside of Guadalupe near the southwest tip. A third animal, too close to the cliffs to permit close ex- amination, was also believed to be a gray. The two verified sightings were both adult animals 1 1 or more meters in length. Cow-Calf Groups As was noted earlier, the routes taken by females with calves during the spring migration have been un- known. Twenty-three northward migrating groups containing mothers with calves were observed during the aerial sur- veys (Figure 6). The earliest was sighted 18 February, the latest on 18 May. Although the majority of those sightings were well inshore, this may 47 be a result of the heavy sighting effort inshore in 1972 during the times of the northern migration. The few sight- ings of mothers with calves late in the season, however, were more off- shore. Of the 23 times mothers with calves have been observed, in 18 mothers and calves have been either by them- selves or with other mothers with calves. In only four instances were they in the company of other adults. This observation may be supported in part by the fact that females with calves are not receptive to breeding because a female calves and breeds in alternate years (Scammon. 1874; Gil- more. 1961; Rice and Wolman. 1971). Yearlings There is still little information in the literature on the distribution and movements of yearling gray whales. Hubbs (1972 pers. comm.) has ob- served solitary yearlings migrating south very near shore off La Jolla. Gilmore (1960b) reported that year- lings frequently travel with larger adult animals on the southern migra- tion, presumably learning the migra- tion route, but that solitary individuals are also seen. Based on the growth curve of gray whales (Rice and Wolman. 1971) and on estimates of size range at time of weaning (Gilmore, 1961). all whales estimated in our surveys to be be- tween about 6 and 9 meters (20-30 feet) long were classified as yearling whales. The opportunity to observe Gigi (8.26 m |27 ft] long) from the air for nearly an hour in early March 1972 verilied the accuracy of my previous size estimates and increased confidence in the reliability of the classification in subsequent sightings. The room for error in this estimate notwithstanding, yearling-sized whales were observed with higher frequency than expected (Figure 7). A total of 21 yearlings or groups of yearlings was observed in the study area. Of those. 16 were observed after the re- lease of Gigi (Evans. 1972) all during Figure 6. — Locations of sightings of mottier-calf groups during aerial sur- veys. 1969-72. Figure 7. — Locations o( sightings ot probable year- ling gray whales (estimat- ed size. 20 to 30 feet) dur- ing aerial surveys, 1969-72. ^Z"""'"'^''^i^9> liiiiiiiiiii '^..rrr^ "m^ 1 *--%..---— >^;;|lliil s ;■;■;: • NOV '^ \ ANGEL • DEC »~"\ :■:;: ' JAN ■\^ ' FEB • MAR • ^ • APR '^ \ OCEAN- » MAY <=^ * vicis; Iv *\'"m V - NO SIGHTS OF YEARLINGS SOUTH THIS CHART **^i - NO SIGHTINGS OF YEARLINGS OFFSHORE ♦ 1 - 27 AND 28 APRIL 1972 X 8 YEARLINGS FROM A PT CONCEPTION NORTH TO MONTERREY BAY ♦ r 34° 33° 32° 120° the period of the northward migration. No yearlings were seen south of the Coronado Islands, but a total of 16 was encountered on a 2-day surve\ flight north to Monterey Bay in April. All were within 5 km of the beach. No yearlings were observed in the offshore areas where other whales were seen. Further, like cows and calves, yearlings tended to be either by themselves or with other yearlings. In only 4 of the 2 I cases were year- lings accompanying adult animals. This absence of yearlings with adults may be a result of the forced rejection 119° 118° 117° h\ the mother at the lute summer weaning in the north. Rates of Movement Estimates of rates of movement for southward migrating whales have ranged from 7.7 km/hour calculated over the entire migration route (Pike. 1962) to 10.2 km/hour calculated over a small segment of the route (Cummings et al.. 1968). Rice and Wolman (1971) used ihe times of peak passage at two separate shore stations to calculate the average distance trav- 48 eled In 24 hours as 185 kni. Pike (1962) used the same calculations to determine that northward migrants traveled from 56-80 km/day at about Vi-'/i the rate of southern migrants. During this study, natural markings on three whales observed on successive days permitted the calculation of speeds of movement along two areas of the coastline. Rates of movement of all 3 are comparable to Pike's calculations. Two 12-1.^ meter individuals, one distinctly marked with white brush markings on the tail stock and flukes, were seen 11. 12. and 13 April 1972. During the 49.5 hours between the first and third sightings, they moved approximately 129 km from the Coronado Islands to near .San Cle- mente. Calif., an average speed of only 2.6 km/hour. A 12-meter individual with a nearly all white tail fluke and a wide white band across the tail stock was seen with four other animals off Point La Jolla on 27 March 1972. The same animal was observed again on the 28th just northwest of Newport Beach and on the 29th 13 km south- west of Point Vincente. Net movement in 44 hours was 128 km or 2.9 km/ hour. Finally, an unusually dark yearling observed just south of Point .San Luis 27 April 1972 had moved 64 km to the north when it was resighted 23 hours later northwest of Point Estero. It had moved at an average rate of 2.8 km/hour. SUMMARY Results of periodic aerial surveys are comparable to those from ship and land-based surveys in defining the timing of migration of gray whale populations past southern California. Peak densities were observed in Janu- ary for the southward and in March for the northward migration. Over half the population observed passed more than 64 km offshore from San Diego. Cows with calves were seen from February through May primar- ily inshore and tended to be alone or with other cows with calves. Yearling whales were seen inshore from Feb- ruary through April and tended to be solitary or with other yearlings. Fi- nally, average speeds observed for three individuals over small segments of the northward migration route were comparable to estimates based on peak movements past shore stations. ACKNOWLEDGMENTS I am indebted to many people for help with this project. John Hall and Larry Tsunoda each flew some of the survey flights. George Lingle and John Moore helped summarize the data. Raymond Gilmore. Dale W. Rice, and William F. Perrin read the manuscript and made useful sugges- tions. Marita Doerflein. Marty Allen, and Shirlee Preis typed the manu- script. Finally. I am indebted to the officers and men of Carrier Antisubmarine Air Groups 53 and 59 for their skill, patience and helpful spirit, and to LCDR Al Zollers for scheduling air- craft. This research was part of NUC IR Project 150550 "Marine Mammal Populations," W. E. Evans principal investigator. LITERATURE CITED Adams, L. 1968. Census ol the gray whale, 1466-67. Nor.Hvalfangsl-Tid. 57:41-43. Cumniings, W. C, P. O. Thompson, and R. Cook. 1968. Underwater sounds of mi- grating gray whales, EsiluiLiuiiis i;Uiiicus (Cope). J. Acoust. Soc. Am. 44: 1278-1281. Evans. W. E. 1972. A mobile maruie en- vironmental survey vehicle. NUC TN No. 758. Evans, W. E., and J. S. Lealherwood. 1972. The use of an inslrumenled marine mam- mal as an oceanographic survey platform. NUC TP No. 311, 11 p. Gilmore. R. M. 19??. The return ot the gray whale. Sci. Am. 192(l):62-74. . 1960a. A census of the Cali- fornia gray whale. U.S. Fish Wildl. Serv., Spec. Sci. Rep. Fish. 342. 30 p. 1960b. Census and migration of the California gray whale. (In Engl, and Norw.] Nor. Hvalfangst-Tid. 49: 409-43 1 . 1961. The story of the gray whale. 2nd ed. Privately published, San Diego, 16 p. 1969. The gray whale. Oceans 1:9-20. Gilmore, R. M., and G. Ewing. 1954. Calving of the California grays. Pac. Dis- covery 7(3): 13-15. Hubhs, C. L. 1959. Natural history of the grav whale. Proc. XVth Int. Congr. Zoo!., Sect. III. Pap. 46, 3 p. Hubbs, C, L.. and L. C. Hubbs. 1967. Gray whale censuses bv airplane in Mexi- co. Calif. Fish Game 53:23-27. Pike. G. C. 1962. Migration and feeding of the grav whale iE.Mhncluins >;ibbosiis). J. Fish Res. Board Can. 19:815-838. Rice. D. W. 1961. Census of the Califor- nia grav whale. 1959-60. (In Engl, and Norw.] Nor. Hvalfangsl-Tid. 50:219-225. . 1965. Offshore southward mi- gralion of gray whales off southern Cali- fornia. J. Mammal. 46:504-505. Rice. D. W.. and A. A. Wolman. 1971. The life history and ecology of the gray whale {Eschruhliiis nihiisiiis). Am. Soc. Mammal. Spec. Publ. No. 3. 142 p. Scammon. C. M. 1874. The marine mam- mals of (he north-western coast of North America. John H. Carmany and Co.. San Francisco. 3 19 p. Wyrick, R. F. 1954. Observations on the movements of the Pacihc gray whale. Eschnchinis i^taicciis (Cope). J. Mammal. 35:596-598. MFR Paper 1055. From Marine Fisheries Review, Vol. 36, No. 4, April 1974. Copies of this paper, in limited numbers, are available from D83. Technical Information Division, Environmental Science Information Center, NCAA. Washington, DC 20235. 49 MFR PAPER 1056 A Note on Gray Whale Behavioral Interactions with Other Marine Mammals J. S. LEATHERWOOD With the exception of reports of killer whales, Orciniis urea, attacking gray whales. Esihricltuus nihti.siii\. (Scammon, 1874; Andrews. 1914; Gilmore. 1961; Burrage. 1964; More- John, 1968; and Baldridge. 1972) there are no accounts in the literature on the behavioral interactions between gray whales and other marine mam- mals. During aerial surveys of south- ern California cetaceans, (Leather- wood. 1974). I often observed gray whales in close association with other marine mammals (Figure I). Though the abundance of all these species in the area during the winter and spring makes coincidental association likely. the following incidents represent be- havioral interaction; Four days after her release, when she was first relocated by aircraft, the gray whale Gigi (Evans. 1974) was swimming with a small group of Pa- cific bottlenose dolphins Tiirsiops sp. in the surf zone just north of the San Clemente. Calif, pier. Though the dolphins left the whale shortly after the aircraft began to circle the area. when first seen they were closely clustered about the head of the gray whale as if riding its pressure wave. Since Gigi was housed during almost her entire internment at .Sea World with an Atlantic bottlenose dolphin. iursiops iniiu alii.s. this association in the wild may have been a result of the captivity. However. I have ob- served gray whales swimming with bottlenose dolphins in the wild in six other instances, in three of which the porpoises were also riding the whales' pressure waves. Further, bottlenose dolphins arc common along the Baja California portion of the gray whales" migration route and in the breeding lagoons and have been reported mov- ing freely among California gray whales (Evans and Dreher, 1962). On 19 January 1972. three adult gray whales were observed heading southwest over Sixty-Mile Bank (lat. 32°()5'N. long. 1 18° lO'W). The entire area was rich with birds and the sur- face action of many schools of small fishes and a large aggregation of odon- tocetes (including over 1.000 northern right-whale dolphins. Liwoclclphis htircalis. approximately 500 Pacific common dolphins. Dclphiiiiis dclphis. approximately 500 North Pacilic white-sided dolphins. Liiiicnoihynclius ohUqKuicns. and at least 3 Dall por- poises. Phocoenoidex dcilli) was pres- ent. The whales were observed at close range from a helicopter for nearly 45 minutes and dolphins and porpoises were observed riding the pressure waves of the whales for the entire J. S. Leatherwood is with the Naval Undersea Center Bio- Svstems Program, San Uiego, CA 92132. time. All species were involved in the interaction. In addition, during this same period gray whales were observed riding the large glassy swells which moved through the area. This behavior is common among small dolphins (e.g.. 1 iirsidps. Di'lphiiuis. La^enorhyiuhiis, Lissodctphis) and is perhaps not sur- prising for the gray whale in the light of its reported surf-riding (Cald- well and Caldwell. 1963), In March 1971. several gray whales were observed along the west side of Catalina Island where an estimated 200 pilot whales. Glchiccpliald sp., were distributed in small groups from Ben Wesson Point to the northwest tip of the island. One gray whale was turned belly up in the midst of a pod of 12 or 15 pilot whales, and an adult pilot whale was swimming over the belly of the inverted gray whale. Both were alarmed by the aircraft and sounded on our approach. In the other instances (Figure 1) the animals were simply swimming close to each other. With one excep- tion, that of Gigi. all the observed associations between gray whales and other cetaceans involved adult whales. Figure 1. — Locations ol sightings of gray whales associated with other ma- rine mammals (1969-1972). IURSIOPS SP DEIPHINUSDELPHIS GLOBICEPHALASP PHOCOENOIOES DALLI LAGENORHYNCHUS OBLIQUIOENS LISSODEIPHISBOREALIS - Z = ZALOPHUS CALIFORNIANUS 120 iir 118° 117 50 all greater than 30 feet in length. Furthermore, in all cases the gray whales have appeared to be passive participants in the interaction. LITERATURE CITED Andrews. R. C 1914. Monographs of the Pacific Cclacea. I. The California gray whale {Rhiichuinecifs gUiiicus Cope). lis history, habits, external anatomy, osteology and relationship. Mem. Am. Mus. Nat. Hist. (New Ser.) 1:227-287. Baldridge, A. 1972. Killer whales attack and eat a gray whale. J. Mammal. 53:898- 900. Burrage, B. R. 1964. An observation re- garding gray whales and killer whales. Trans. Kansas Acad. Sci. 67:5.'^0-5? 1. Caldwell, D. K., and M. C. Caldwell. 196.3. Surf-riding by the California gray whale. Bull. South. Calif. Acad. Sci. 62(2):99. Evans, W. E. 1974. Telemetering of tem- perature and depth data from a free rang- ing yearling California gray whale, £.«7i- richtnis rohiisiiis. Mar, Fish. Rev. 36(4): 52-58. Evans. W. E., and J. J. Dreher. 1962. Ob- servations on scouting behavior and the associated sound production by the Pacific bottlenosed porpoise (Tiir.siopi i;illi Dall). Bull. South. Calif. Acad. Sci. 61:217-226. Gilniore, R, M. 1961. The story of the gray whale, 2nd ed. Privately published, San Diego, 16 p. Leatherwood, J. S. 1974. Aerial observa- tions of migrating gray whales, Eschrich- liiis robustus, off southern California ( 1969- 1972). Mar. Fish. Rev. 36(4):45-49. Morejohn, G. V. 1968. A killer whale- gray whale encounter. J. Mammal. 49: 327-328. Scammon, C. M. 1874. The marine mam- mals of the North-western coast of North America. John H. Carmany and Co., San Francisco, 3 19 p. MFR Paper 1056. From Marine Fisheries Review, Vol. 36. No. 4, April 1974. Copies of this paper, in limited numbers, are available from D83. Tecfinical Information Division. Environmental Science Information Center, NOAA. Wasfiington. DC 20235. MFR PAPER 1057 Aerial Observations of Gray Whales During 1973 Radio communications with shore observers permitted coordination of observational efforts. Time, location, numbers of whales, and behavior ob- servations were noted for the sight- ings and photographs were attempted on occasion. 122* OO'W I MONTEREY OAV 1 N / / ^^MONTEREY ^: " CYPRESS -r YANKEE PT,.f AOBSERVATION -A SITE LOBOS ROCKS l % PT SUR -^ •^... obsefved from ptore V S§ A„. oDierved from shore SCALE 1 250.000 Figure 1. — The area off California observed for gray whales. 15-23 January 1973. PAUL N. SUND antd JOHN L. O'CONNOR During their annual southward migration California gray whales. Eschrichliiis rohiisnis. were observed between Monterey Bay and Point Sur. Calif. (Figure 1) from an air- craft during the period 15-23 January 1973. An aerial survey was initiated in response to recommendations of the Joint Naval Undersea Center — National Marine Fisheries Service (NMFS). Southwest Fisheries Center Gray Whale Workshop (held in La Jolla. California in August 1972). that the accuracy of the annual NMFS shore census taken near Yankee Point be checked. The survey was designed to compare shore observers' estimates of numbers with those of aerial ob- servers; to test the estimate that 95 percent of the gray whales migrating by Yankee Point pass within 1.9 km (1.2 miles) of the shore (Rice and Wolinan. 1971); and to provide ob- servations of gray whale behavior and associations with other marine mam- mal species. The utility of aerial sur- veys in cetacean research has been demonstrated by Levenson (1968) and Leatherwood ( 1974a. b). This paper reports on simultaneous shore and aircraft observations and discusses the problems inherent in each method. METHODS Five flights, totaling 13.6 hours, were made between Monterey Bay and Point Sur. Calif. (Figure I) in a Cessna 172 flown by a professional spotter-pilot at altitudes ranging from 150 m (500 ft) to 900 m (3,000 ft). RESULTS AND CONCLUSIONS From the aerial observations made in the sector scanned by shore obser- vers, the following points were deter- mined: Of 24 paired observations (individuals or groups observed by both air and ground personnel), ini- tial visual contact was made by a ground observer in eight instances and by an airborne observer in ten in- stances. Hence, ground and aircraft observers apparently were equally adept at initially sighting whales. Of the 24 paired sightings, the aerial observers were able to correct the Paul N. Sund is with the Pacific Environmental Group, National Marine Fisheries Service, NOAA, Monterey, CA 93940. John L. O'Connor, P.O. Box 1942, Newport Beach, C A 92660. 51 numbers recorded by the shore ob- servers six times. In three instances of poor (white caps and 4-6 foot swells) sea state conditions, on the other hand, the aerial observers were unable to contirm groups or individuals sighted by the shore observers. These data suggest that, although aerial observa- tions may be more directly limited by sea conditions, they are useful in quantifying the number of whales in groups. Further, resolution of num- bers present is faster from the air than from shore. (It often takes the shore observers up to 30 minutes to determine their count for a given group — during which time the in- dividuals in the group may dissociate or join with others.) Resolution of numbers of whales in groups is more rapid and apparent- ly more accurate from the air than from shore. With a professional spot- ter pilot working a limited area — such as that scanned by the shore ob- servers— in good sea state conditions, essentially no whales will pass unno- ticed. "Misses" by the aerial observers were due to leaving the area premature- ly in order to accomplish other tasks; had the aircraft been consistently in the shore observers' area (and immedi- ately outside to prevent unnoticed passage of individuals offshore) none would have gone unrecorded. The aerial observers made ."^O ob- servations of whales involving 149 animals. All these observations oc- curred within 7 miles of the shoreline, even though the area surveyed ex- tended to 25 miles seaward. Of these sightings. 98 percent were within 5 miles of shore. 96 percent within .^ miles, and 94 percent within I mile. Distances were estimated by making timed runs at constant speed from pi>sitions offshore to the coastline. The observations of this study tend to confirm Rice and Wolmans state- ment that 95 percent of the whales pass within 1.9 km (1.2 miles) ot the shore near the Yankee Point site. Gray whales have been reported interacting with other marine mam- mals by Leatherwood (1974b). but during this study no other marine mammals were observed "associating" directly with gray whales. Feeding behavior was observed on two occa- sions. A calf was seen accompanied by an adult. These two latter observa- tions are of particular note and the senior author intends to publish the details elsewhere.' ' Sund. P N Manuscript Evidence of feeding during migration and of an early birtti of the California gray whale LITERATURE CITED Leatherwood. J. S. l'J74a. Aerial observa- tions of migrating gray whales. Eschrich- liiis rubusitts, otT southern California (1969-1972). Mar. Fish, Rev. 36(4):45-49. . 1974h. A note on gray whale behavioral interactions with other marine mammals. Mar. Fish. Rev. 36(4):49-?0. Levenson, C. 1968. Factors aftecling bio- logical observations from the ASWEPS aircraft. U.S. Naval Oceanogr. Off., In- formal Rep.No. 68-102, 6 p. Rice. D. W., and A. A. Wolnian. 1971. The life history and ecology of the gray whale {Eschnchtnts nihusius). Am. Soc. Mammal., Spec. Publ. No. .3. 142 p. MFR Paper 1057. From Marine Fisheries Review, Vol. 36. No. 4. April 1974. Copies of this paper, in limited numbers, are available from D83. Technical Information Division. Environmental Science Information Center, NOAA, Washington. DC 20235. MFR PAPER 1058 Telemetering of Temperature and Depth Data From a Free Ranging Yearling California Gray Whale, Eschrichtius robustus W. E. EVANS ABSTRACT //; /y6(S' //((■ iiinlinr iiiiluilcti a .scries nf Miii.lics iisiiii; icidic iniii.sniillcr.s lo jollow ilw nidViincnls iiiitl sliidy ilw cliviiii^ hchiivior ol snuill Icollwil whales. This paper dc.si ril'cs the miulifu iilit'irs tij this ccpiipniciU necessary lo use this Icchniquc on larj^cr wTnilcs. in this case a yciirliiii; California ,t,'/((y wliale, Eschrichtius robustus. In addition lo the iransinission of positional data, i.e. azinuilh anil deplh of dive, the ittsininicnlalion pnekaf^e used in this study was desii;ncd lo trausnui environmental data (tcinperaturc-al-depihl. The animal used in this study, a Jemalc E. robustus, U(/.v captured on /.■? March 1971. in Smnimon's Lagoon. Baja California Siir. Mexico, hy Sea World, Inc., San Diei.;o, and released on 13 March 1972. at hit. 32''4I.5'N. lonn- 1 17^^ 20.5' W {off Point Loina. San Die.i^o. Calif.) hy the Naval Undersea Center (NUCI. San Diei;o. Rtulio contact was maintained with the animal iinlil .'^ May 1972. Deplh oj dive and leinperalure-al-deptli data w ere idnlniuouslv mniiiloreil for a 24-hoiir period. INTRODUCTION The present stud\ is an extension of a 6-year research program designed io evaluate the feasibility of usmg medium-si/ed lo large cetaceans, in- strumented with a combination data collection and transmission system. to measure physical oceanographic parameters at various depths, and to evaluate the relationship of these parameters to cetaceans' movement patterns and secondary productivity (Evans. 1970. 1971. in press). Because of the impending release of a yearling California gra\ whale 52 W. E. Evans is with the Naval LJndersca Center. San Diego, C A 92132. (Gigi II) captured by Sea World, Inc., San Diego, on 13 March 1971, in Scammon's Lagoon. Baja California. Mexico, and the timing of the northern migration of CaMfornia gray whales (March-Aprill, the program was ac- celerated to take advantage of this opportunity. The prototype data trans- mission/acquisition system had been designed and bench-tested in anticipa- tion of tests on a Pacific pilot whale. ClohiccphaUi cf. sctiniiiuini. in mid- summer 1972. The unit was repack- aged and the test dates subsequently moved up to coincide with the planned release of the Sea World captive year- ling gray whale which was scheduled for 13 March 1972. It was then field tested attached to the ,Sea World gray whale when she was relased at 0905 hours at lat. 32°4I.5'N. long. 117° 20,5'W into a group of four to five California gray whales moving north. DATA PARAMETERS Since one of our primary purposes for using a data system attached to a cetacean was to measure environ- mental parameters associated with the animafs movements below the air-sea interface, the instrumentation used must indicate the depth at which the measurement was made. The follow- ing parameters were considered as po- tential indicators of productivity and important correlates of cetacean movement; 1. Temperature at depth. 2. Ocean current speed at surface and at depth. 3. Salinity-derived from conduc- tivity measurements 4. Dissolved gases: a. O2: b. No; c. FreeC02. 5. Light; a. Absorption loss due to molec- ular absorption, particulate matter; Figure 1. — Block diagram of telemetry transmitter attactied to yearling California gray wtiale (Gigi). b. Backscattering from particu- late matter; c. Light level at depth. After consideration of all these parameters, temperature was selected as the most desirable for this phase of the program because; 1) methods of measurement are straightforward elec- tronically. 2) considerable bathyther- mal data exist for the California C ur- rent region, 3) data transmitted from the instrumented animal could be easily checked by use of currently available expendable bathythermo- graphs, and 4) a great deal of data relating the thermal structure of the water columns to primary and secon- dary productivity are available in the scientific literature (e,g. Eckman, 1953). INSTRUMENTATION Data Transmission System The data acquisition system mount- ed on the yearling gray whale pro- vided measurement of the depth of each dive and the water temperature at that depth, and served as a radio beacon for tracking. Data measured was telemetered by an 1 I meter trans- mitter (27.585 megaHertz) to either a surface vessel, shore station, or air- craft-based receiving set which would also demodulate the data being trans- mitted. Directional information for tracking was obtained by a special fast response automatic direction finder developed several years ago specifical- ly for this type of application (Ocean Applied Research Corporation, San Diego, Model ADF210).i A block diagram of the telemetry transmitter is shown in Figure I . Func- tion and operation are as follows; Pressure is measured by a semi- conductor strain-gauge bridge excited with constant current. The output voltage is amplified by three opera- tional amplifiers connected in an "instrumentation amplifier" configura- tion and the peak pressure reading stored (remembered) on a capacitor which is followed by an insulated-gate field-effect transistor (LET). This peak detector is inside the feedback loop of the amplifier which maintains accuracy and also yields a digital zero at point A when pressure is de- creasing from the peak depth. This level is used to hold the temperature reading. ' Use of trade names in this publication does not imply endorsement of commercial products by the National Marine Fisheries Service 53 Temperature is measured by a therm- istor composite which is pressure protected in a thin-wall stainless steel tube. The thermistors' conductance is measured by an "operational trans- conductance amplifier" (OTA) whose output is gated by the digital signal from the pressure sensor. The output of the OTA drives a capacitor which serves as a temperature-reading mem- ory. It is also followed by an insulated- gate FET whose high input impedance prevents memory discharge. These two voltage analogs are con- verted to frequency analogs by voltage controlled oscillators (VCO). The fil- tered outputs of the VCO's are summed and the resulting composite fed to the amplitude modulator of the 3-watt peak transmitter. A programmer is also included to provide a 4-second data transmission time when the animal first surfaces followed by a series of short pulses which are adequate for the tracking system. A seawater connection be- tween the antenna tip and the instru- ment case generates a delayed reset for all capacitor memories and the programmer. In the package used on the yearling gray whale two batteries were included Figure 2. — Photograph of the Ocean Applied Re- search Corporation data transmitter Model WDT- 920 attached to the Sea World yearling gray whale (Gigi) just prior to release. (Photo courtesy of J. S. Leatherwood.) Figure 3. — Aerial photograph of lest animal taken on 16 March 1972. as she was swimming through kelp beds off San Clemente, California. (Note kelp trailing behind the transmitter package.) (Photo courtesy of J. S. Leatherwood.) in the system. One had a capacity of 1.^ ampere hours and was used to power all electronics which were on when the animal was at the surface. The second, smaller, battery, which had a 1.2 ampere hours capacity, powered the depth and temperature instrumentation continuously. The ex- pected life of the smaller battery was approximately I month while the larger battery with its greater capacity and reduced duty cycle should con- tinue to provide tracking transmis- sions for as much as 9 months. The entire system packaged and attached to the whale is shown in Figure 2. During the first month of operation. V '/, WAVE MARINE ANTENNA BAND PASS FILTERS TEMPERATURE DISCRIMINATOR n DEPTH DISCRIMINATOR _ - DIGITAL READ OUT TAPE RECORDER Figure 4. — Block diagram of the telemetry data receiving and recording system. performance of the Instrument/Bea- con package was satisfactory with the notable exception of transmission range which was initially more than 25 miles. Subsequent tests indicate that the antenna, which is a top loaded stainless steel whip antenna, had sus- tained some damage. The animal was. on two occasions, observed swimming through kelp and kelp was seen hang- ing on the antenna. Figure 3. Cali- fornia gray whales are also known to rub on the bottom, a behavior which could have abraded or even severed the loading coil from the antenna, drastically reducing its radiation ef- ficiency. The estimated useful range of the damaged system was on the order of 10 miles. The original antenna design em- ployed on beacon transmitters for ma- rine mammals (specifically porpoises) was an adaptation from a design which had been in use for some time on radio beacons used for the recovery of oceanographic instruments. It con- 54 Figure 5. — Automatic direction finding antenna (loops) and data acquisition antenna (whip) attached to the belly of a U.S. Navy S-2 tracker aircraft. (Photo courtesy of J. S. Leatherwood.) sisted of a solid fiberglass tapered rod onto which was wound a conductor and loading coil. An aluminum tip served both as a seawater contact and as a section whose length could be trimmed tor peak field strength. A proprietars coating protected the con- ductor and coil from seawater. The antenna was entirely successful on Delphiinis species (Evans, 1971). but problems were encountered when a similar design was used on captive whales such as pilot whales and killer whales. The captive whales invariably broke the antennas by rubbing on structures or boats and in the instance of the release of a pilot whale into the wild, the antenna was broken by sea- weed. Subsequently, a spring-wire antenna was designed which could be severely bent without catastrophic damage and has been used success- fully on the aforementioned whales (Martin. Evans, and Bowers. 1971). This type of antenna was used on the gray whale pack. Subsequent simula- tions of various types of damage to this antenna indicate that modifica- tions would be in order before em- ploying this type of antenna again. Specifically, the arrangement of the spring at the base should be changed to allow the antenna to be bent double against the transmitter case without damage. The antenna should be length- ened somewhat to reduce the variation in impedance for a given variation in the relative position of the ground plane (sea surface) and the loading coil should be fully encapsulated in the nonmetallic antenna's structure to completely eliminate the abrasion damage potential. Data Receiving System The data receiving and recording system illustrated in Figure 4 was originally tested on board the NUC RV Cape. Subsequent to the initial tracking and data acquisition attempts following the release of the whale on 13 March 1972. the system was placed on board a U.S. Navy S-2 tracker aircraft. The antenna mounting con- figuration used on this type of aircraft is shown in Figure 5. The whip anten- na is shown in the retracted mode. The loop antenna used in conjunction with the automatic direction finding system is adjustable and was aligned prior to every flight by using a shore-based radio beacon. Several relocations of the animal were made using this system. The short transmission range of the damaged transmitter system attached to the whale seriously limited the acquisition of temperature and depth data from the aircraft-mounted system. Tests >-*%► .„ r*-^?25B»-^ /-""':.' pz::^ f^% -P Figure 6. — California gray whale breaking the the back. The normal sequence of a blow is note exposure of the dorsal ridge. (Photo courtesy surface exposing only the head and fore-part of shown right to left at the bottom of the figure, of J. S. Leatherwood.) 55 Gray Whale Relocation Records Enlargement Of ThiB Area Figure 7. — Map of California coastline showing (Gigl) 13 March-5 May 1972. conducted following the release of the whale using a similar data transmitter with one-third the power of the system used on the test animal and a modified antenna have yielded data acquisition ranges up to 40 nautical miles. RESULTS During the initial 2 hours after re- lease of the test animal, signals were very intermittent and seldom longer than 2 seconds in duration. Ohserva- tions lead us to believe this was a behavioral problem since the animal frequently broke the surface of the water showing onl\ her blow hole and mid-portion of her back as illustrated in Figure 6. Since the data transmitter was mounted on the dorsal ridge (on the last half of the body) the antenna either did not break the surface of the water, thus no transmission, or only the tip of the antenna broke the sur- face, resulting in a very short duration transmission. locations o( the Sea World yearling gray whale This resulted in limited data recep- tion during the first 2 hours after re- lease and subsequent loss of the ani- mal's location and movement pattern. Those signals over 2 seconds in dura- tion that were received during this time period did indicate temperature- at-depth values reasonable for the lo- cation and time of year (e.g.. above 20 meters temperatures of 13°-I4°C and below 20 meters a temperature of 7.4C'). A 20-meter isothermal layer is not uncommon at this location. Since the quality of radio signal ac- quisition was quite poor, the search from the RV Cupc was abandoned in favor of an aerial search. The animal was relocated on i.^i March between 1300 and 1500 hours on a bearing of 320°T south of Oceanside. The animal was relocated again on 16 March close inshore off San C'lemente. Calif., working slowly north. The photograph shown in Figure 6 was taken at this time. On this flight and those that followed, although the animal could be easily located, acquisition of use- able temperature-at-depth data was limited I) by the long time interval between adequate exposure of the an- tenna, and 2) by the apparent short range of the transmissions received. Areas of visual relocation and radio contact from 16 March 1972 to 5 May 1972. are illustrated in Figure 7. After a period of 5 to 6 days, the animal's swimming pattern changed and longer and more frequent trans- missions were being received. In order to verify these observations and. if possible, to collect temperature-at- depth data over a 24-hour period, the RV Ciipc left San Diego at approxi- mately 1600 hours on 20 March 1972 for the Dana Point-San Clemente, Calif, area. At IS4() hours. 3.'^ nautical miles from San Clemente. Calif., we acquired weak signals from the animal bearing 340°T. At 2300 hours, signal level had increased and we were re- ceiving bearing and temperature-at- depth data. Initial data indicated tem- peratures of 12°-I4°C at depths of l.'^-20 meters. At 2350 hours the animals diving behavior changed and indicated some dives to depths of 170 meters. Triangulation placed the ani- mal at a location approximately on the 100 fathom curve. 1.7 nautical miles off Laguna Beach. Calif. (Aliso Can- yon). Although the depths recorded at this location were realistic if the animal was diving to the bottom, the water temperatures at those depths appeared to be anomalous. At this HktlMUM DOWH TIME - 16 m Figure 8. — Mean down times and depths of dive as a function ol time of day recorded 20-21 IVIarch 1972. 56 time of the year one would expect sur- face temperatures between 12° and i4°C. and temperatures at 170 meters of 7°-8°C or less. Data from the animal, however, indicated tempera- tures-at-depths of 100-170 meters ranging from 10° to 14°C. If these levels were indeed accurate, a signifi- cant temperature inversion layer was present. This cruise was terminated at 2100 hours on 21 March 1972. after having recorded data for approximate- ly 24 hours. In addition to the temper- ature-at-depth data, the following observations were made: 1. The animal was offshore 1-2 nautical miles after sunset, moved inshore 100-200 meters from the beach post -sunrise. 2. The diving pattern at night was regular, as compared to an erratic pattern during daylight hours. 3. The animal was observed in Dana Cove along with three other gray whales of a similar size range. All four animals left the Cove in late afternoon. 4. The mean time between trans- missions was significantly longer from 1600 to 0400 hours than during the remainder of the day (Figure 8). Since transmissions were more pre- dictable after sunset, our aircraft data acquisition flights were scheduled at night. Under this plan, data were col- lected on 28 and 29 March from the S-2 tracker aircraft in the vicinity of Dana Point, Calif. The recorded data from these flights indicated dives of 50-80 meters and temperatures of I2°-14°C. The observations that the animal moved offshore (1-4 miles) at night were verified. No readily apparent explanation was available for the relatively high temperatures recorded at depth on 20-21 March. To check on these measurements, the RV Sen Sec was sent to the Dana Point area to work from 6 April 1972 through 10 April 1972. equipped with an expendable bathythermograph (XBT) system ca- pable of measuring temperature versus depth over a range of 0°C-30°C to depths of 450 meters. During the Figure 9. — A composite of three expendable bathytliermograph plots collected 2 miles oil Dana Point, Calilornia, at 1700 hours on 10 April 1972. period 6-7 April, the area south of Dana Point was searched and no con- tact was made with the animal, al- though one small 7-8 meter whale was sighted. The XBT data, however, in- dicated surface temperatures of approx- imately 13°C which dropped to 6°C at 300 meters, with no obvious Iher- mocline or temperature inversion. Late on 7 April, a search was made north of the Dana Point area by auto- mobile and signal acquisition was made from the Huntington Beach pier at 1600 hours. Observers on the pier claimed to have sighted a small Cali- fornia gray whale with a radio pack swimming north 100 meters off the end of the oi'^'- at 1000 hours on that same day. Our signal acquisition was on a bearing of 280°T which would 1 1 J - ••-"(• - - J lOCAIION. \.J mlieS OFF LAGUNA lEACH. ' j CAlIf Il*tl. IBOS / ■ ANGE TEMPCRATUIt ATDCPTM RCCOIDfD / HIS, 10 m 7] TO 0830, 31 in 73 Figure 10. — A composite of three expendable bathythermograph plots collected 1.7 miles off Laguna Beach, California, at 1800 hours on 10 April 1972, compared to temperature versus depth data collected from Gigi on 20 March 1972. place the animal between Seal Beach and Santa Catalina Island. On 10 April 1972. the RV Sea See started a search north of Dana Point at 1600 hours. The first XBT station was at 1700 hours. 2 miles off Dana Point. A plot of temperature versus depth representative of the three mea- surements taken at this location is presented in Figure 9. The vessel moved north to approximately the same location where the temperature- at-depth data were collected from the whale on 20 March. Of major interest here is indication from the XBT data that a rather significant temperature inversion did exist in this area. A plot of the XBT station taken at 1800 hours on 10 April. 2 miles off Laguna Beach compared to the temperature- at-depth data transmitted from the whale is illustrated in Figure 10. It should be noted that although the re- lationship between the XBT and whale data appears to be comparable at depths of 100-200 meters, these are preliminary data. Conclusion should not be made without further verifica- tion of the thermal inversion shown in Figure 10. It is possible that the outfall of the San Onofre nuclear power plant north of this location is dumping warm water back into the sea. It has also been shown that at this time of year the mean geostrophic flow at 200 meters has northbound components (Wyllie, 1966). Depend- ing on the temperature, volume, and depth of the San Onofre effluent it is not inconceivable that inversions such as that shown in Figure 9 could result. This, however, is pure speculation at this point. ACKNOWLEDGMENTS This study was accomplished under funding from NASA. Defense Pur- chase request A-70496A, RTOP 160- 75-81, Task 01, Ames Research Cen- ter, Moffett Field, California. Addi- tional funding support was received from the Naval Undersea Center, San Diego, California, Independent Re- search project ROOO-OI. All of the electronic equipment used to instru- 57 nient the whale and subsequently track and obtain data Ironi it was de- signed and manufactured by Ocean Applied Research Corporation. San Diego, California. Hugh Martin and Romaine Maiefskl. both from this organization, actively participated in the attachment of the instrumentation to the animal and the initial stages of tracking. J. S. Leatherwood. J. Hall. Bruce Parks, and L. McKinley. of the Naval Undersea Center. .San Diego. California, and the Commanding Of- ficer of the RV Cape and his crew were directly instrumental in the suc- cess of this project. The radio contact with the instrumented whale on 5 May 1972 was accomplished by Paul Se- besta. NASA Ames Research Center. Moffett Field. Calif., using equipment supplied b\ the author. due to the destruction or displacement of melanin in the epidermis of the area treated. LITERATURE CITED Eckman. S. 1953. Zoogeography ol llie sea. Sidgwick and Jackson Ltd.. Lond.. 417p. Evans. W. E. 1970. Uses of advanced space technology and upgrading ihe future study of oceanology. AIAA 7th Annual Mtg. and Tech. Display. Houston, Tex., Pap. No. 70- 1:?.^, p. I-.^. . 1971. Orientation behavior of delphinids; Radio telemelric studies. Ann. N.Y. Acad.Sci. 188:142-160. . In press. Radio lelenietnc studies of two species of small odonlocete cetaceans. In W. E. Schevill (editor). The Whale Problem. Harvard Press, Cambridge, pp. 385-394. Martin, H., W. E. Evans, and C. A. Bowers. 1971. Methods for radio tracking marine mammals in the open sea. IEEE Eng. in the Ocean Environ. Conf.. p. 44-49. Wylhe. J. G. 1966. Geostrophic How of the California Current at the surface and at 200 meters. Calif. Coop. Oceanic Fish. Invest. Atlas No. 4. ,\iii + 288 charts. MFR Paper 1058. From Marine Fisheries Review, Vol. 36, No. 4, April 1974. Copies of ttiis paper, in limited numbers, are available from D83. Technical Information Division, Environmental Science Information Center, NCAA. Washington. DC 20235. MFR PAPER 1059 POSTSCRIPT During the period 2 January 197.^- 21 March 1973. the author investigated 37 reported resightings of Gigi. Al- though most of these reports did not check out, on 5-6 January, a Captain Paul Roth. USN. and a Mr. and Mrs. Sherwood of San Diego independently described behavior of a 9-10 meter California gray whale sighted inside the kelp off the Sunset Cliffs area of Point Loma. San Diego. California. In both cases the whale, light in color. approached close to small vessels less than 10 meters, rolled, and frolicked around. On 15 March we received a report from the MV Loiii; Bench Prince that a whale of similar size and with white tail Hukes (see Figure 3) and a fiO cm X 60 cm square white scar behind the blow hole was sighted frolicking around the vessel by 178 whale watchers. The location of this sighting was 3-4 miles off Point Fermin. This latter sighting is es- pecially interesting since on 6 March 1972, one week prior to release, Gigi II was branded using cryogenics with a 60 cm x 60 cm mark, midline on the back just posterior to the blow hole. This form of marking, called "freeze branding. " results in a white scarring Capture and Harnessing of Young California Gray Whales, Eschrichtius robustus KENNETH S. NORRIS antd ROGER L, GENTRY ABSTRACT 1 lii\ paper reptirls mi the tleuiils i>f capture , liarnessiiii;. ircukiiii;. ami lianiess release for three suckluiii i:ra\ u/ki/cv. These lesls are ihe firsl steps in a pr(ii;raiii Id ilevelop new means af clala acqiiisilion and recovery jri'in wliales diirini; iheir mii^raiiinis. I) is hoped hy tliese means u> develop new infornuilion ahoiil popiilaliini routes and hence population immhcrs to assist nianai;einent. Capture was hy tail noosiiii^ and liead nelliiii; from a fishins; vessel equipped with a swonljisli plank. The liarness. placed on the inptive ashore, was held in place over tlie pectoral fins and hcuk hv means of a pair of inelal plates held together hy a \oliihle nnc.;ne\inm holt . Trackiiii^ was hy radio. INTRODUCTION Informed whale management re- quires adequate knowledge of popula- tion numbers. Uncertainly about mi- gratory pathways and population mi.\- ing makes determination of such num- bers uncertain for some whales such as the humpback {Mci^aptera novaeaii- Siliae). the blue whale {Balaenoptera iniisciihis). the (in whale iBalaenop- lerii phxsaliis). and the minkc whale {Balaenopiera aciorostraia). Thus pre- cise information on migration routes of these and other marine mammals would materially assist in the develop- ment of sound management practice (Anonymous, in press). In spite of decades of work with Discovers and other tagging methods (Clarke, 1957) our knowledge of whale migration remains highly incomplete. Because such information is needed for some protected species, new tag- 58 Figure 1. — Map ol capture locality. Nuinbers indicate the capture sites for the ttiree harnessed animals. ging methods that do not require kill- ing are now required. These methods seem to fall into two categories; (1) those involving the capture of whales, placement of harnesses and equipment on them, tracking along the whale's route, and subsequent release and re- covery of data packages; and (2) those involving placement of data or tele- metering packages on whales without capture, followed by tracking. The first method will allow data collection from a few animals, while the latter will presumably allow less complete data collection from more animals and from those species that cannot be captured. The tests de- scribed here are of the first sort; that is. they involve capture and harness- ing. The experiments of Evans (this number of Marine Fisheries Review) with Gigi are also of this sort, though surgical attachment rather than har- nessing was used. We chose our subject, the California gray whale, because large numbers of suckling calves are available in their Mexican breeding lagoon during January and February of each year and because the calm working condi- tions in the lagoon would assist these preliminary tests. We expect that the majority of results obtained on this relatively well-known animal will be applicable to more oceanic species. Our tests were restricted to capture, harnessing, and very short term track- ing, since we expected that our results would require harness redesign prior to long-term tracking. This proved to be the case. We attempted to capture suckling animals only because of the obvious dangers and seamanship problems pre- sented by adult whales. The rationale supporting this choice is that a suck- ling calf, harnessed and instrumented, should keep station with its mother and. hence, give a true migratory route. To our knowledge five baby gray whale captures or handlings have been reported. Eberhardt and Norris ( 1964) report working with a stranded baby gray whale in Scammon's Lagoon. Robert Eisner (pers. comm.) detailed a capture of a baby gray whale in Scammon's Lagoon from a small cata- maran by use of a superficial harpoon followed by netting. David Kenney (pers. comm.) directed the capture of Eisner's animal and the capture and transportation of Gigi. the gray whale calf caught in Scammon's Lagoon and held for 12 months in Sea World. The latter whale was captured with a tail noose from a small fishing vessel equipped with a bow plank. The ship was reportedly damaged slightly by the mother when the baby was brought alongside. Theodore Walker (Cous- teau. 1972) is shown manipulating a stranded baby gray whale in circum- stances much like those discussed by Eberhardt and Norris (1964). Spencer (1973) reported on the drug-assisted capture of adult whales in Scammon's Lagoon. THE STUDY SITE We chose northern Magdalena Bay. Baja California Sur. Mexico, near Boca de Soledad for our work because of an abundance of whales living in a system of shallow bays and rather narrow channels and because Kenneth S. Norris and Roger L. Gentry are associated with the Coastal Marine Laboratory, Uni- versity of California, Santa Cruz,' Santa Cruz, CA 95064. the Mexican government has recently declared the better known Scammon's Lagoon (Laguna Ojo de Liebre) a whale reserve. Headquarters were es- tablished in the small government cannery town of Lopez Mateos. which fronts on the main lagoon channel 8 km southeast of Boca de Soledad (Figure 1). In this region the channel is about 800 m wide and averages 1 1 m deep in mid-channel. To the west a low ridge of dunes separates the lagoon from the sea. The shore along the dunes drops precipitously into deep water. The eastern bank is typically bordered with dense mangrove thick- ets often cut by shallow bays and channels. The shore along the man- grove coast usually shelves gradually over a broad tidal flat to the main channel. This difference in bottom con- tour proved crucial to capture and harnessing. While whales were found through- out the deeper parts of the channel, one concentration occurred just in- side Boca de Soledad and another oc- curred at a broad expanse of water just north of Colina Coyote (see Figure 1). It was here, or somewhat closer to Lopez Mateos. that our captures took place. Our counts showed approximate- ly 86 whales in residence in the entire channel system. Most were mothers and young, but a few males were pres- ent, as indicated by copulations ob- served inside the channel. WHALE CAPTURE AND HARNESSING Capture of suckling gray whales proved to be rather simple, once the basic techniques were established. Four whales were netted in 3 days (27-29 January 1973). One was released be- cause it was clearly too large for our 59 harnesses. The other three were suc- cessfully harnessed, released to their mothers, and tracked. Capture was performed from the swordfish boat Loiison. a 15-m vessel equipped with a II .5 m welded aluminum pipe pulpit projecting from its bow. During cap- ture Captain Tim Houshar occupied the basket at the end of the pulpit, while the helmsman steered from a remote station atop the crow's nest. The vessel was maneuvered behind a whale pair, attempting to place the netman in the pulpit over the animals as they surfaced to breathe. At the same time another crewman in a speedboat zigzagged around and in front of the animals in an attempt to direct and distract them. This attempt succeeded often enough that surfacing whales rather regularly allowed the pulpit to pass over them. The tendency to surface beneath the pulpit varied rather widely from pair to pair and seemed most consistent in mothers with small young. Once a pair surfaced under the pul- pit a noose of 1.25 cm nylon line was placed over the small animal's head by means of a large metal hoop cut through at its outer margin and held together inside a piece of plastic tubing (Figure 2). The rather slow speed of the whales (usually less than 7 knots) and the relatively long time they spend at the surface during res- piration make this a reasonably sim- ple process. At this point the nylon noose which was tied to the metal hoop with light twine was pulled loose. The hoop separated over the animal and was pulled away, leaving the noose to slip back to the tail stock of the little whale. Another crewman on the pulpit pulled the noose tight over the tail stock. The noosed young took out a modest amount of line, usually less than 100 m. before the line was belayed around a Samson post. The young did not dive for extended periods (less than 1 minute) but towed the vessel for a time in this position. The mother always stayed in close attendance. Figure 2. — Capture of the baby whale. Note hoop and noose being placed over the baby. Note also the swordfish plank which is maneuvered over the mother-young pair. often sliding over the line or coming up underneath it. At times she lifted the young on her snout or back, and occasionally she thrashed at the re- straining line with her flukes. Once the young animal began to slow somewhat, it was brought back under the pulpit by bringing in line. The mother came with it and swam under the pulpit or slightly off to the side. Never did a female attempt to hit the boat or the pulpit, though our small sample may not be representative. A head net bag of 5 cm nylon mesh, also containing a noose of 1.25 cm nylon line and similarly positioned on a hoop frame, was placed over the baby's head. Optimally this net was deep enough to extend from the tip of the snout to just posterior to the pectoral flippers. In practice our nets were too small for all but one animal and placed the noose anterior to the pectorals. Even so. the noose did not slip loose. With lines fore and aft the young animal was severely hampered and could be pulled in rather easily by hand. During this time the boat and skiff had been maneuvering the pair toward the east bank and its shallow shelf. Two plastic trash barrels containing the coiled head and tail lines were lift- ed into a waiting skiff and payed out to the restrained whale until the shallow shelf was reached. Then the lines were taken ashore and the men. usually four to six. pulled the baby sideways onto the shelf. Usually the mother's efforts were strenuous at this time, and occasionally she looped the line over her body or tail giving an irresistable pull, but always she rapidly slipped free and the baby could be towed in again. The baby was beached in about 0.7 m of water. 10 m or so from the shelf edge. The mother was unable to enter such shallow water, though she did patrol the shelf edge, and in one case partially stranded herself, seem- ingly in an attempt to reach the baby. Thus protected from the obvious ire of the mother, it was rather simple to 60 place ihc harness on the baby. The danger from the mother was made clear when a crewman began working within a few meters of one. The female whale lifted her tail, bent it back and thrashed the flukes around in a semi- circle, horizontal to the water surface. She missed the man by quite a dis- tance but the force of the blow was enough to send a sheet of water over everyone nearby. The baby remained rather quiet during the harnessing process. The harness was usually slipped on under the snout and v/orked posteriorly to the pectorals which were then inserted through the harness. The harness was then tightened in place until snug over the baby's body. At this point, timing for harness release began as a corrosi- ble magnesium bolt which held the release mechanism began to corrode away in salt water. Three or four men pushed the baby back into deep water over the shelf taking care to avoid the mother. In all but one case she was nearby and quickls took up station with her off- spring. In one case the mother left before the baby was launched and was a kilometer or so down the bay shore when the baby began to swim in deep water. This baby cruised quietly for a short time and then, when about 300 m from the mother, turned as if on a signal and raced toward her. The mother did the same, turning toward the baby and beginning to swim rapidly. Once they were near the mother circled the baby, thrashing the water with her flukes. It was prob- able that an acoustic recognition sig- nal was involved. This young animal had been emitting short low frequency signals while stranded. Even if the young did become separated from the mother by some distance, chances for reunion remained excellent because of the restricted channels available for swimming. In all cases the presence of the har- ness had no visible effect on the be- havior of the mother-young pair. HARNESS DESIGN The harness was constructed of four lasers of one-way stretch Lino 241,' commonly used in fabricating girdles and corsets, that permitted expansion and contraction around the whale's circumference. The two legs of each harness half (Figure 3) were attached together ventrally by "D" rings to a timed-release mechanism. Dorsally they were bolted to a curved metal plate holding the radio trans- mitter. Horizontal rows of grommets 5 cm apart in the heavy plasiic- impregnated nylon reinforcing band at the dorsal ends of the harness legs allowed adjustments to animals of different circumferences and allowed the harness to be secured under differ- ent degrees of tension. We pulled the harnesses snug on our animals, which prevented flutter from water passing around the swimming animal and kept the harness in place during dives (the harness was 40 cm wide and 1 12 cm long). The strength feature of the harness was a 2,5 cm wide by 0.6 cm thick woven nylon strap in the leading and trailing edge of each harness half. These straps, held in sewn folds of the harness, were sewn to the harness only near the ventral "D" rings, thus per- mitting harness and straps to be ad- justed independently to the whale's circumference. The grommeted ends of both the harness itself and the strengthening straps were attached to bolts on the dorsal plate by means of knurled nuts. A plastic cup on each side by mid- body simulated an instrument housing, and a poK vinyl chloride rod sewn across the harness above the pectorals acted as a batten, preventing bunching of the harness in the anterior-posterior direction. The timed-release mechanism con- sisted to two aluminum plates held together by a central spring-loaded ' Reference to Irade names does not imply en- dorsement by the National Marine Fishieries Service, NCAA magnesium bolt. One plate had four tapered corner posts that tit into four receptacles on the other plate. The "D" rings of the harness legs slipped over the posts and over four strong springs that assisted in forcing the plates apart during jettisoning. All tensions of the harness and nylon straps were e.xerted against these posts. The magnesium bolt bore only the vertical strain of a spring between the two plates. The wall thickness of the magnes- ium bolt determined the interval be- tween submergence in seawater and the time of breakage. When the bolt broke the springs forced the two plates apart and released the "D" rings from their posts. Corrosion of the bolts was insured by a central copper sleeve that promoted rapid electrolysis. The dorsal plate to which the har- ness attached was constructed of ? mm curved aluminum, designed to fit over the body contour of a baby whale. An Ocean Applied Research Model PT-202 radio transmitter was secured to the center of this plate, and a paint- ed yellow cap moulded of high density polyurethan foam was fitted over the transmitter for flotation. Foam neo- prene sheeting was glued to the ventral surface of this plate to prevent chafing the whale's skin. To fasten the harness around the animal, the two halves, connected ventrally to the timed-release mechan- ism, were slid under the animal and the pectoral flippers inserted through the harness. The radio, float, and plate were placed on the dorsal midline, and each harness half was pulled tight; the appropriate rows of grommets in the harness were fitted over bolts in the dorsal plate and the nuts tightened down. Then the excess rows of grom- mets were cut off with a knife and the heavy nylon straps secured in place and similarly trimmed. Finally straps from the float were attached, and the calf was ready to be launched to its mother. Figure 4 shows the harness and radio in place as the released calf joins its mother. 61 Figure 3. — The harness, radio transmitter and timed release mechanism: (A) OAR PT-202 radio transmitter (B) 5 mm curved aluminum dorsal plate (C) Plastic-impregnated nylon re- inforcing sewn on harness of Lino i^ 241 material (D) Nylon reinforcing strap sewn into harness and bolted to dorsal plate (E) Rows of grommets (F) Knurled nuts holding harness to dorsal plate (G) Instrument housing (H) Polyvinyl chloride bat- ten (I) Harness legs with "D" rings (J) Polyurethan flotation device attached by straps to dorsal plate (K) Timed-release mechanism (L) Alu- minum corner posts to which "D" rings of har- ness legs attach (M) Receptacles for above posts — spring loaded (N) Magnesium bolt passes through spring loaded hole in top plate and secured with a nut. Dimensions: (1) Harness width 40 cm (2) Harness length 112 cm from timed — release mechanism to first row of grommets <3) Distance between each of five rows of grommets — 5 cm (4) Length of harness legs 40 cm (5) Timed release mechanism 10 x is cm. TRACKING AND HARNESS RECOVERY The three harnessed whales re- mained within a few hundred meters of their release points (see Figure 1). Visual tracking in daylight was greatly assisted by the bright yellow float and upper harness which were visible even a foot or two underwater. in the first release, after some time in the water, the calf swam purpose- full> toward the Unison, turned on her side, and rubbed the harness against the hull and keel of the boat — breaking the float partly loose, releas- ing one "D" ring, and snapping the fiberglass radio antenna. Transmission of radio signals immediately ceased. This damage could have been prevent- ed by our maintaining a greater dis- tance from the harnessed animal. The timed-release mechanism contained a ."^-hour bolt which had not released by the time darkness fell. The harness was recovered 2 days later in vegeta- tion along the channel edge, about 2 km from the release point. The second release, timed for some- what less than 5 hours, went flawlessly, including radio tracking and harness release. The third release was planned for 20 hours, with tracking overnight from the Loiisim. To assist after dark should the radio malfunction, a water- proof lifejacket light was ti.xed to the float. Though both radio and light functioned at release, thev failed before 62 Figure 4. — Mother and young swimming with harness and radio in place. dark, and the animal was lost during the night. However, shortly after dawn the released harness was found floating within 60 m of the vessel. Details of these releases and trackings are presented in Table 1. DISCUSSION The capture methods described here for suckling gray whales are remark- ably effective and simple. Except when the mother is under the pulpit or at the edge of shallow water, the methods seem relatively safe. Given enough shipboard power the noosing methods would work with larger animals, though the sheer bulk of an adult would make any movement by the whale, purposive or not. dangerous. This would certainly be a prime con- sideration in any attempt to affi.x a harness on an adult. The harness described here would, with minor modifications, serve nicely for short-term tracking and instru- mentation of small gray whales. Be- cause a whale attains 66-72 percent of its adult size in the first year (Rice and Wolman. 1971). growth during the first months is e-xtremely rapid. Harnesses for periods of more than a week must therefore include a device that allows for growth but also keeps a constant tension and locks if the Table 1. — Harnessing and tracking of gray whale calves. Animal Planned Netting to number Girth Length bolt life beachir '9 Beaching to Date and name Sex (m) (m) (hr) (mm) release (m in) Tracking 1/27/73 (1) Carl(a) F 2 41 4 80 5± 30 ± 37 ± 4 hr, 45 mm track, release time uncertain 1/28/73 (2) Lee M 2 17 4,20 5± 18 ± 14 ± 3 hr, 16 mm 1/29/73 (3) Baia F 2.51 5 16 20 ± 28 ± 8± 17 hr. 23 mm to harness recovery. Time to release uncertain. animal rubs the harness against under- water obstructions. Another concern on any long-term track is abrasion of the harness. The purposive rubbing of whale No. 1 against the capture ship and its mother caused damage to the radio antenna and serious abrasion to the lower har- ness legs. On whale No. 2 the abdomi- nal legs of the harness were abraded through the girdle fabric and into the flat nylon strap in several places, even though the animal wore the harness for only ?• hours. 16 minutes. Behavi- oral observations suggest that much harness wear results when the baby rubs against the barnacle-covered back of the mother and slides to one side as she surfaces. None of these problems was more than very minor in these tests. But clearly long-term tracking with increased exposure to obstacles along the migratory path will exacerbate these problems greatly. More durable materials, such as metal or the strongest fabric, and more re- silient radio antennae will be needed for successful long-term tracking. The release mechanism dependent upon magnesium bolt corrosion worked adequately, but variations in water temperature and salinity could un- predictably alter release time. Long release times (more than a week) may require a new system, such as the use of electroexplosive or electronic re- lease mechanisms that might allow an operator to release the harness upon command. Harnessing is probably the least injurious means of attaching instru- ments to cetaceans, and harness place- ment around the pectoral flipper area is probably optimal. Pectoral place- ment insures maximum exposure of the antenna, minimal body movement 63 during swimming, and relatively little change in girth during diving. Further, when physiological data are to be tak- en, most important vital areas (lungs, heart, brain) are nearby. In our opinion package volume could be relativeh high, providing it is weight compensated until nearly iso- static. A baby whale might well carry 15-20 kg of instruments properly housed and shaped to reduce drag. Instrument placement is probably best just above or between pectorals where it would cause the least disequilibrium. In these positions it would be most difficult for the whale to rub the instru- ments loose. Any such package, of course, would have to be strongly protected from impact and abrasion. The harness used here was designed with a float at the top to suspend the antenna with the harness hanging be- low so that when cast off it rode easily with the antenna in the vertical posi- tion for good transmission. In conclusion, the first steps of whale capture and instrumentation have been taken, but much remains to be done to transfer the methods to (I) long term trackings. (2) other species which must be caught and handled at sea, and {}) adult whales. Jose Castello of the Consejo Nacional Ciencias y Tecnologi'a, Mexico City; and Jaime Dommguez and Mario Camparan of the Escuela Superior de Ciencias Marinas, Ensenada, Baja California Norte, Mexico. We thank Frank Brocato for con- sultation on whale capture and for constructing much of our gear. We are especially grateful to Edwin Janss and Richard Wheeler of the Janss Foundation for support of the field study. A National Aeronautics and Space Administration subcontract No. 23196 (NA.SA NAS2-68601 al- lowed harness preparation. LITERATURE CITED Anonymous. In press. Report of Working Group on Bio. and Nail. Hist. In W. E. Schevill (editor). The Whale Problem. Harvard Press, Cambridge, pp .''-10. Clarke, R. \^^1. Migrations of marine mammals. [In Engl, and Norw.] Nor. Hvalfangsl-Tid. 46:609-6.K). Cousteau, J. Y. 1972. The whale. Mighty monarch of the sea. Doubleday &. Co., Garden City, .104 p. Eberhardt. R. L., and K. S. Norns. 1964. Observations of newborn Pacific gray whales on Mexican calving grounds. J. Mammal. 4.S(1):88-9.S. Rice, D. W.. and A. A. Wolman. 1971. The life history and ecology of the gray whale {Exchruiuiiis rohusiti.s). Am. Soc. Mammal.. Spec. Publ. No. .1, 142 p. Spencer. M. P. 197.1. Scientific studies on the gray whales of Laguna Ojo de liebre (Scammon's Lagoon), Baja California, Mexico. Natl. Geogr. Soc. Res. Rep., 1966 projects, p. 23-*'-25.1. MFR Paper 1059. From Marine Fisheries Review, Vol. 36, No. 4, April, 1974. Copies of this paper, in limited numbers, are available from D83, Technical Information Division. Environmental Science Information Center. NOAA, Washington. DC 20235. ACKNOWLEDGMENTS Permission to study the gray whale came from both the Mexican and United States governments, and many people helped. Prominent were Carl L. Hubbs of Scripps Institution of Oceanography; George Gross, U.S. Fisheries Attache, U.S. Embassy, Mexico City; and Philip Roedel and Robert Miller of National Oceanic and Atmospheric Administration, U.S. Department of Commerce. We thank our willing and skillful field crew: Captain Tim Houshar and the crew of the Louson, Richard Pierce, Ken- neth Balcomb. and Thomas P. Dohl of the University of California, Santa Cruz; Gerald Kooyman of Scripps Institution of Oceanography; Robert Gibson oi the Franklin Institute Re- search Laboratories. Philadelphia; Opposite. — Gigi II, witti transmitter affixed to back, awaits release at sea off San Diego. Ptioto by J. S. Leattierwood, courtesy of Naval Under- sea Center. San Diego, Calif. Vf GPO 799 418 64 UNITED STATES DEPARTMENT OF COAAMERCE NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION NATIONAL MARINE FISHERIES SERVICE SCIENTIFIC PUBLICATIONS STAFF ROOM 450 1107 N E 45TH ST SEATTLE WA 98105 FOURTH CLASS POSTAGE AND FEES PAID U S DEPARTMENT OF COMMERCE COM-210 OFFICIAL BUSINESS '^?6-l9l^ < \