SOUND PRODUCTION, SCHOOLING, AND FEEDING HABITS OF THE MARGATE, HAEMULON ALBUM CUVIER, OFF NORTH BIMINI, BAHAMAS!

WILLIAM C. CUMMINGS,2 BRADLEY D. BRAHY,

AND JUANITA Y. SPIRES Institute of Marine Science, University of Miami

ABSTRACT The behavior of a school of margates, Haemulon album Cuvier, was studied with hydrophones and an underwater television system. Margates entered the acoustic-video underwater observation area about sunrise. They schooled during the day and dispersed in late afternoon. Feeding and other activity increased considerably at night. Common food orga- nisms included bivalve mollusks, crustaceans, and small fishes. Nighttime and daytime diets were of similar composition. The sounds of feeding and other activities were recorded on magnetic tapes. Underwater television observations were made of margates schooling, feeding, and being preyed upon by amberjacks and barracuda. Identifiable natural characters and Petersen disc tags were used to determine that after nocturnal foraging, most margates returned to school in the same place each morning. Large margates, however, were not observed to school.

INTRODUCTION Margates, Haemulon album Cuvier, are grunts of the family Pomada- syidae. They are uncommon in Florida waters but their range includes Florida and the Bahamas to Brazil (Courtenay, 1961). In the Bahamas, margates as large as 50 em are taken by fishermen using hand lines or wire traps. This study developed from previous observations of underwater sounds associated with margates (Cummings et a1., 1964; Kumpf, 1964). Earlier magnetic tape recordings indicated feeding and general activity of margates were greater during the day than at night. These findings did not agree with literature on other grunts, or with the authors' field experience. Consequently, additional tape recordings were made in con- junction with underwater television and SCUBA diving observations, stomach content analyses, and tagging of the margates. The major objec- tive was to determine the schooling and feeding habits of a particular school of margates under relatively natural conditions.

'Contribution No. 699 from the Institute of Marine Science, University of Miami. Work supported by Office of Naval Research, Contract Nom 840(13). 'Present address: U. S. Navy Electronics Laboratory, San Diego, California. ] 966J Cummings et al.: Sound Production of the Margate 627 Margates produce at least three underwater sounds of relatively low intensity: I-a burst, which occurs in a series of 3 to 10 rapid pulses, each with principal frequencies in the range of 50 to 1600 Hz; 2-a pop, consisting of a single pulse of short duration with principal frequencies from 20 to 700 Hz; and 3-a blast, in the frequency range of 10 to 500 Hz with a duration of 0.2 to 1.4 sec (Cummings et al., 1964). The burst is a stridulatory sound associated with bottom feeding. The pop, associated with feeding in the water column, and the blast, are probably caused hydrodynamically by sudden forward movements or changes in direction of the fish. Grunts are notorious for producing grating sounds while they are held in the hand, either in or out of the water (Burkenroad, 1930; Tavolga, 1965). The authors noted similar sounds produced by hand-held margates; however, it is questionable whether these sounds have any behavioral significance in the natural life of the animal. In fact, these grating sounds were never heard from margates in their natural environment during 5 years of bio-acoustic studies in the Bahamas. Published information relative to schooling and feeding of margates was scattered, with few or no supporting data. Jordan & Evermann (1902) dcscribed the margate as a deep-water fish which schools when spawning in early summer. They noted that margates entered shallow water at night to feed upon crabs, crawfish, and worms. Longley & Hildebrand (1941) reported that large, adult margates occurred offshore from Loggerhead Key, Florida, whereas smaller fish were more common inshore. La Monte (1946) described the margate as an offshore fish which frequents coral and rocky areas. Longley & Hildebrand (1941) noted that bluestriped grunts, Haemulon sciurus (Shaw), fed at night and schooled by day. They also reported that schools of French grunts, Haemulon [lavolineatum (Desmarest), broke up at dusk and scattered over the reefs to feed, mostly on crustaceans, mollusks, annelids, and small ophiuroids.

METHODS The period of study was April 1963 to April 1964. The area of study was located about 1 mile off the west coast of north Bimini, Bahamas. Most observations were made with the Acoustic-video System, Institute of Marine Science, University of Miami. Capabilities of the system were described by Steinberg et al. (1962), Kumpf & Loewenstein (1962), Steinberg & Koczy (1964), and Kronengold et al. (1964). These refer- ences and one by Cummings et al. (1964) list techniques used in the present study. They include making magnetic tape recordings of under- water sounds, simultaneous sound and video observations with underwater television (UTV), underwater observations with SCUBA and the sub- marine, CUBMARJNE,and still and movie photography. The underwater 628 Bulletin of Marine Science [16(3)

7 BLASTS, MOVEMENT SOUNDS ------7 DAYS APR.-OCT. 1963 5 " DAYS OCT.-DEC. 1963 3

1- I I I 2400 0400 0800 1200 1600 2000 2400 30 en UJ U 26 OPS, PLANKTON FEEDING SOUNDS Z UJ 22 ------14 DAYS APR.-OCT. /963 a: a: II DAYS OCT. -DEC. 1963 :::> 18 u u a /4 LL. /0 a 6

r I I I I 1 -r 1 2400 0400 0800 1200 1600 2000 2400 UJ (!) BURSTS, BOTTOM FEEDING SOUNDS « 8 0:: ------"DAYS APR.-OCT. 1963 UJ 6 8 DAYS OCT.- DEC. 1963 «> 4 j'-/vvJ\ /:~0\ \ 2 " ,/\ ,l ~ I •••••,,\ ,~, ." /'\ ,/ \ '\ l \ t V h • \ /1, 1'\ .\ .'~\. , '~...•' \, / "'....: \. t'o":,/ \ / \ /\ l \ ; \ ''. -," '\ l • , ., •••••• , I ,,,' l,..... •.•••••• \ .'\ I '.: ',\,' ~ .-r- ,- 1 'I 1 I '. r ¥ I" I '-"I'-"---~I -j 2400 0400 0800 1200 1600 2000 2400 TIME OF DAY FIGURE 1, The daily occurrence of three types of sounds showing the increase after October 1963, when a dense school of margates had collected around the underwater instruments. The ordinate shows the average number of sounds, over the number of days indicated, which occurred dueing each half hour of the day, Note the high frequency of sound occurrence during daylight, when the fish were concentrated in a school, and the low frequency of occurrence at night, when the fish dispersed. 1966] Cummings et at.: Sound Production of the Margate 629 120

100 :r /'.. (J) I.L

I.L 80 0 a:: 1LI r CD ,A/\-. :::E 60 / . :::l / / Z

1LI c:> 40 ct a:: .J 1LI ~ 20

-;-••••-;- I ~~... " I I I I I I I I I I I 1·-( I j-·'t-., r I 2400 0300 0600 0900 1200 1500 1800 2100 2400 TIME OF DAY FIGURE 2. Average number of margates in the field of view throughout the day. Counts were made on the half hour. An average of 22, 5-second counts per day were made on 12 separate days between January and April 1964. television camera and the hydrophones were bottom-mounted at a depth of 60 feet (18.3 m) in an area of sparse sea grasses. Details of the habitat and its fauna were given by Kumpf (1964) and Steinberg et al. (1965). Approximately 250 hours of live UTV monitoring and 35, 24-hour magnetic tape recordings were used in this study. A comparison was made of the food ingested by day-caught and night- caught margates that had been captured by hook and line fishing. Other specimens were taken with longlines and wire traps, but these methods were comparatively inefficient. A total of 210 margates were collected in the study area. Contents of the esophagus, stomach, and gut were removed within 3 hours after capture. The contents were fixed in 20 per cent formalin and preserved in 40 per cent isopropyl alcohol. Volume of the material was determined by water displacement in graduated cylinders.

RESULTS Schooling and Movements.-Margates were occasionally sighted from April 1963, when the equipment was moved to the study area, to October 1963. By mid-October 1963, a school of about 50 margates had collected, and 2 months later, there were 300 to 400 fish clustered around the equipment. The increased number of fish was reflected by a corresponding increase 630 Bulletin of Marine Science [16(3 )

IZ •.... w w LL. 10 Z

:E ~ 8 •...... / 0 a:l 0\.~ LL. 6 . ..•/'\. ..•. LL. - 0 .....J 0 0 :I: 4 (.) \fVJ en LL. 0 •.... 2 :z: (!) w :z: 2400 0300 0600 0900 1200 1500 1800 2100 2400 TIME OF DAY FIGURE 3. Average height off the bottom of margates which schooled at the study site during the daylight hours. Ninety-four estimates were made over 6 days during January 1964. of feeding sounds (Fig. 1). No other margate schools were noted within 600 ft (183 m) of the study area. Each day the fish assembled at the video site from about 0530 to 0830 hours (Fig. 2). The school was formed by small groups and individuals which swam in from various directions. Movement at this time of day was random. The fish were scattered, and feeding in the water column was frequent. The fish were highest in the water column during the morning hours (Fig. 3). At about 0900 hours, the distribution was more uniform and compact; the fish headed into the water current and were less active. When predators approached, activity increased as the margates milled about and crowded under the camera. A gradual reduction in numbers was observed from 0930 to 1800 hours (Fig. 2). Larger margates (up to 55 cm) swam by during the day without joining the school of smaller fish (20-40 cm). Observations in the nearby areas, including SCUBA dives to 250 feet (77 m), revealed no schools of large margates. Larger fish occurred individually or in very small, scattered groups which quickly swam over the bottom, stopping occasionally to feed. Numerous schools of small margates near rocky areas were noted by the senior author during dives in several other areas in the Bimini Islands. 1966] Cummings et al.: Sound Production of the Margate 631

..c :::t. I OJ \ "'0 \ , •• . \' U) .\ , \ .. tI) I.f"I ",-:",_.. ... ,_', \ fo~'.;..J If) \\ --r ~~\ \ \ \ Z \ .\', '::;jN. \ ...... ~N.\ \'.\ ~ j' ,...... \ ~~,.~~ -.J \ \ ; \ . \ \ . lLJ \, ", _.\ .. 1 , \' 'i \ .. i I +2 • I. I. _: 1.. \ .• .\ - \ .. : . 1.' > -~\; i.:... \\ .. lLJ .r-... . ! . \ \ I -.J _.~__L~~.+- ! '..~i ..• : ::.\ : '..i: .. iil. lLJ , I 0 , j ,i I f, +.). - f a: i.r I i => --.--t- en -2 . i ; en I I lLJ -4 I a: a.. -6 z0 -/0 0=> -/4 en 2200 2/00 TIME OF DAY FIGURE 4. Ambient noise recording in the 200 to 2000 Hz band, taken 28 August 1963. This is an example of many such recordings which showed the increase in noise level during illumination. The sudden movement of margates when the lights were switched off caused a blast-like sound shown as a high spike in the above recording at about 2225 hours.

The school under study became more active at about 1800 hours. After this time, individuals and small groups swam away until all the fish had disappeared from view (Fig. 2). Underwater floodlights were used for viewing after dark. Margates were seen only occasionally during short (5 to 15 seconds) periods of illumination (Fig. 2). They became plentiful only after the floodlights remained lighted for about 5 minutes. Although the dispersal of margates at sunset explained the paucity of their feeding sounds at night (Fig. 1), the initial question of their nighttime feeding activity remained unanswered. Feeding and Food.-Pop sounds were recorded as margates snapped with convulsive body movements at plankton. Plankton captured by margates 632 Bulletin of Marine Science [16(3 )

<.D 2: C\J NO. OF FI SH (,) I z <.D SIZE DAY NIGHT :J: /6 -26 78 24 I- -"ן (.!) m 27-37 19 24 Z I L&J I"- ..J C\J 38-48 5 14

C Q:

in the field of view included larval and juvenile fishes, and smaller, uniden- tified organisms. Notwithstanding frequent conditions of excellent visibility, good UTV image resolution was not attained with very small objects which moved quickly through the field of view at close range. Burst sounds were recorded from bottom-feeding margates. A margate about to feed on a benthic crustacean would assume a nearly motionless head-down position, with its head 5 to 15 em, and its tail 10 to 35 em, above the bottom. This inclination often lasted as long as a minute. Then, it would suddenly plunge its snout into the sand and seize the prey. Shortly thereafter, the fish would assume a level attitude and burst sounds would be heard as sand was expelled from the mouth and opercular openings. Daytime television observations revealed no outstanding period of bottom feeding. This was shown more quantitatively with the sound data (Fig. 1). However, plankton feeding was conspicuously frequent from about 0700 to 0800 hours, just after the morning assemblage at the UTV site. This observation is supported with evidence from the sound data (Fig. 1). 1966] Cummings et al.: Sound Production of the Margate 633 TAHLE 1 GASTRO-INTESTINALCONTENTSOF MARGATES

Night-caught fish (N=32) Day-caught fish (N =23) Fish with item Fish with item Item No. % No. % Calcareous sand 22 68.8 13 56.5 Manatee grass 13 40.6 10 43.5 Sponge spicules 1 4.3 Polychaetes 7 21.9 4 17.4 Sipunculids 3 9.4 Stomatopods 11 34.4 3 13.0 Amphipods 2 6.3 Shrimp 9 28.1 2 8.7 Crabs 19 59.4 8 34.8 Pelecypods 5 15.6 3 13.0 Echinoids 3 9.4 Fishes 5 15.6 3 13.0

Plankton was attracted to the site at night, presumably by the under- water floodlights. When the area had been illuminated for 3 or 4 minutes, margates entered the field of view and fed upon the plankton. At no other time of day were the fish more active. Pop sounds from plankton-feeding margates and blast sounds from their rapid swimming movements consid- erably increased the ambient noise level in the lighted hydrophone area (Fig. 4). When the lights were switched off, after the margates had accu- mulated, loud blasts were heard. This occurred more than 50 times in the course of the study. When the area was relighted immediately after such a blast, the margates were no longer in the field of view. Lagler et al. (1962) state that the sphincter and dilating muscles in irises of higher bony fishes, when present at all, are poorly defined. Accordingly, the iris of a margate may adjust slowly to the sudden darkness, causing temporary blindness and startled movements. Between 22 January and 17 September 1964, 102 margates were col- lected in the area of study from 1300 to 1600 hours, and 62 from 0200 to 0530 hours. This collection was made to study their feeding habits by examining stomach and gut contents. Thirty-seven per cent of the day- caught fish and 82 per cent of the night-caught fish contained some solid food material. Fish that contained food were divided into three size groups. In each group, the average food volume was much greater in night-caught fish than in day-caught fish (Fig. 5). This confirmed earlier observations which suggested heavy feeding at night. In addition to the quantitative examination, the food content of 32 night-caught and 23 day-caught fish was examined qualitatively (Table 1). 634 Bulletin at Marine Science [16(3)

140 0(1) N = 131 4 3 120 W=9xIO- L

o (3) en 100 LIJ (.,) Z=> 0 80 z o (6) r- 60 :r: (!) LaJ- ~ 40 0(7) o (10)

20 o (27) 0 (69) 0(8)

20 30 40 50 60 STANDARD LENGTH IN eM

FIGURE 6. The weight-length relation of 131 margates captured at the under- water television camera. 1966] Cummings et at.: Sound Production of the Margate 635 Small crabs were the most common food items in both groups of fish. Crustaceans in general were more abundant in night-caught fish. Less common items were polychaete worms, bivalves, and small fishes, including several garden eels, Nystactichthys halis (Bohlke) . Except for large sipunculid worms (2.5 X 20.0 cm) and small fishes, the food material was reduced to small fragments. Most margates had ingested small amounts of sand and bits of manatee grass, Syringodium filiforme Kutzing, with their food. The capture of margates by hook and line may have introduced sampling bias. First, it is highly probable that these were comparatively hungry fish. Secondly, some food may have been regurgitated as the fish were brought to the boat. However, these factors, if operative, were assumed to equally affect both day and night samples. A source of bias not accounted for is the possibility that the average food volume of both night-caught and day-caught fish was underestimated. Weight-length, Sexual Development, and Tagging.-The weight-length statistic, in addition to being of taxonomic importance, is of interest in studies of biomass and energy relations of coral reef communities. The weight-length relation of 131 margates, including both sexes, was fitted by the equation, W = 9 X 10-4L3, where W is weight in ounces and L is standard length in cm (Fig. 6). A point of inflection appears to be at the 37.5 cm grouping. This is approximately the size of the smallest fish with well developed gonads. Of 210 margates examined, no ripe fish of either sex was noted from the school under study. To determine if the margates which were observed during the day remained in the general vicinity at night, and if those caught at night were part of the daytime school, a sample of each group was tagged. Black Petersen disc tags with large white numbers were attached to 17 day-caught margates, and white tags with black numbers were attached to 10 night- caught margates. The numbers were easily read from the television screen, and within 4 days after release, five different night-tagged fish and five different day- tagged fish were observed during the day. Daytime observations during these 4 days were continuous. At night, IS-second spot checks were made at half-hour intervals, since more extended use of the floodlights attracted margates. Night checks revealed only one day-tagged fish and no night- tagged fish. Sometimes tagged fish were observed to rub their tags against the instrument cables, and some appeared with wounds from one side of the nape to the other indicating that they had lost their tags. Tagged margates appeared repeatedly for 3 weeks after release. After the fifth week no more tagged fish were sighted, but scarred fish which had lost their tags, appeared as long as 3 months later when the camera was taken ashore for repairs. 636 Bulletin of Marine Science [16(3)

FIGURE 7. Top-A photo from the television screen showing the wound inflicted upon a margate by a great barracuda. Bottom-Margates blocking field of view by clustering around camera and tripod. 1966] Cummings et al.: Sound Production of the Margate 637 Predalion.-During the day margates were preyed upon by the great barracuda, Sphyraena barracuda (Walbaum) and by amberjack, Seriola dumerili (Risso). One or two barracuda regularly frequented the general area, and amberjack occasionally appeared in groups of two or three. Amberjack were observed to swallow whole margates about 20 em long. Some margates were deeply scarred, presumably by predators. A photo was taken off the UTV screen of one which had just been bitten by a barracuda (Fig. 7A). Two deeply scarred fish, distinguishable from the rest of the school, appeared repeatedly from September 1963, to January 1964. Similarly, a third fish, with a piece of monofilament line hanging from its mouth, appeared consistently from July 1963, to January 1964. The reappearance of these fish offers further evidence that the margates returned to the same place of schooling. When predators approached, the entire school moved to the bottom and toward the camera, where the fish formed a dense cluster, often blocking the field of view (Fig. 7B). Blast sounds often accompanied the rapid mass movements of margates under attack. At night, barracuda attacked margates which were feeding upon plankton in the lighted area. Blaxter & Parrish (1958) made similar observations with underwater television off the Scottish coast. They noted that mackerel attacked sprats, and whiting attacked herring, as the prey in turn fed upon plankton attracted by underwater lighting.

CONCLUSIONS 1. The accumulation of margates around instruments at the video site indicated the structures were an attraction in the otherwise barren area. The unfailing response of margates under predatory attack to swim under the camera tripod indicated that natural interstices must also have signifi- cant survival value as protection for prey. 2. Frequent predation observed via underwater television, the high occurrence of sounds associated with predation, and the presence of numerous scarred or maimed fish, showed that the schooled margates were heavily preyed upon. The predators included amberjack and great barracuda. 3. Smaller margates occurred in stationary schools during the day and dispersed at night. Large margates probably do not school. 4. Stomach content analyses indicated that schooling margates feed more heavily at night than during the day, but the composition of their diet does not differ greatly. 5. Nightlighting indirectly attracts margates; however, the sudden absence of light apparently startles the fish causing them to disperse immediately. 6. The weight-length relation of margates is estimated to be W = 638 Bulletin of Marine Science [16(3 )

9 X 1O-4L3,where Wis weight in ounces and L is standard length in cm. No sexually mature fish were noted from the school. 7. Tagging results were necessarily limited by small numbers of fish tagged. They indicated, however, that daytime-schooled margates remain in the general vicinity at night, and each morning school in the same place. 8. Recordings of characteristic sounds associated with feeding and movement can be used to monitor the occurrence of these activities. ACKNOWLEDGMENTS The authors are indebted for the advice and criticism offered by J. C. Steinberg, A. A. Myrberg, Jr., C. R. Robins, and W. Davis. Laboratory and resident facilities were provided by R. F. Mathewson, Resident Director, Lerner Marine Laboratory. E. P. Koschen offered technical assistance. The Perry Submarine Co., Fort Lauderdale, Florida, kindly made the submarine, CUBMARINE,available for surveying the general area of study. SUMARIO PRODUCCI6NDESONIDOS,CARDlJMENESY HABITOSDEALIMENTACI6NDEL RONCOBLANCOHaemulon album CUVIER,FRENTE A NORTHBIMINI, BAHAMAS La acumulacion de roncos blancos alrededor de los instrumentos en el lugar de video indico que las estructuras eran una atraccion en el area que de otro modo estaba desierta. La indudable respuesta de los roncos blancos de nadar bajo el tri'pode de la camara frente a los ataques de los predatores indicaba que los intersticios naturales deben ser de significativo valor como proteccion para la presa. La predacion frecuente, observada par television submarina, la gran ocurrencia de sonidos asociados con la predacion y la presencia de nume- rosos peces con lesiones 0 cicatrices mostro que los roncos blancos que forma ban parte de cardumenes eran muy perseguidos. Los predatores incluian coronados y barracudas. Los roncos blancos mas pequeiios se presentaron en cardumenes estacionarios durante el dia y dispersos en la noche. Los mas grandes probablemente no forman cardumenes. El analisis del contenido alimenticio indico que los roncos blancos que forman cardumenes se alimentan mas durante la noche que durante el dia, pero la composicion de su alimento permanece aproximadamente la misma. Observaciones de video sugirieron que los roncos blancos que se alimentan del fondo, manipulan los materiales ingeridos para devolver las sustancias no nutritivas y retener el alimento. La iluminacion nocturna indirectamente atrae a los roncos blancos, sin embargo, la subita ausencia de luz aparentemente espanta el pez haciendolo dispersarse inmediatamente. 1966] Cummings et al.: Sound Production ot the Margate 639

La relaei6n peso-]ongitud de los roneos b]aneos se estima que es W = 9 X 10-4L3, donde el peso (W) es en onzas y la longitud (L) es en em. No se not6 ningun pez sexua]mente maduro en el eardumen. Los resultados de marear fueron neeesariamente limitados por las pequenas muestras, sin embargo indiearon que los roneos blaneos que forman eardumenes diurnos permaneeen en ]a veeindad general durante la noehe, y eada manana se agrupan en el mismo ]ugar. Reportes de sonidos caracteristieos asociados eon ]a alimentaei6n y los movimientos pueden ser usados para deteetar la oeurreneia de estas actividades, suponiendo que los animales que emiten sonidos esten dentro del area aeustiea.

LITERATURE CITED

BLAXTER, J. H. S. AND B. B. PARRISH 1958. The effect of artificial lights on marine organisms at sea. Scottish Home Dept., Mar. Res. 1958 (2): 24 pp. BURKENROAD, M. D. 1930. Sound production in the Haemulidae. Copeia, 1930 (1): 17-18. COURTENAY, W. R., JR. 1961. Western Atlantic fishes of the genus Haemulon (Pomadasyidae): systematic status and juvenile pigmentation. Bull. Mar. Sci. Gulf & Carib., 11 (1): 66-149. CUMMINGS, W. C., B. D. BRAHY, AND W. F. HERRNKIND 1964. The occurrence of underwater sounds of biological origin off the west coast of Bimini, Bahamas, pp. 27-43 in Tavolga, W. N., Ed., Marine Bio-acoustics. Pergamon Press, New York, xii + 413 pp. JORDAN, D. S. AND B. W. EVERMANN 1902. American food and game fishes. Doubleday, Page & Co., New York, 572 pp. KRONENGOLD, M., R. DANN, W. C. GREEN, AND J. M. LOEWENSTEIN 1964. Description of the system, pp. 11-25 in Tavolga, W. N., Ed., Marine Bio-acoustics. Pergamon Press, New York, xii + 413 pp. KUMPF, H. E. AND J. M. LOEWENSTEIN 1962. Undersea observation station. Sea Frontiers, 8 (4): 198-206. KUMPF, H. E. 1964. Use of underwater television in bio-acoustic research, pp. 45-57 in Tavolga, W. N., Ed., Marine Bio-acoustics. Pergamon Press, New York, xii + 413 pp. LAGLER, K. F., J. E. BARDACH, AND R. MILLER ]962. Ichthyology. John Wiley & Sons, Inc., New York & London, 545 pp. LA MONTE, F. R. 1946. North American game fishes. Doubleday & Co., Inc., Garden City, New York, 202 pp. LONGLEY, W. H. AND S. F. HILDEBRAND 1941. Systematic catalogue of the fishes of Tortugas, Florida. Carnegie Inst. Wash., Pub!. No. 535, 331 pp. STEINBERG, J. C., M. KRONENGOLD, AND W. C. CUMMINGS 1962. Hydrophone installation for the study of soniferous marine animals. J. Acoust. Soc. Amer., 34 (8): 1090-1095. 640 Bulletin of Marine Science [16(3)

STEINBERG, J. C. AND F. F. Koczy 1964. Objectives and requirements, pp. 1-9 in Tavolga, W. N., Ed., Marine Bio-acoustics. Pergamon Press, New York, xii + 413 pp. STEINBERG, J. C., W. C. CUMMINGS, B. D. BRAHY, AND J. Y. MAcBAIN (SPIRES). 1965. Further bio-acoustic studies off the west coast of North Bimini, Bahamas. Bull. Mar. Sci., 15 (4): 942-963. TAVOLGA, W. N. 1965. Review of marine bio-acoustics, state of the art: 1964. Tech. Report, NAVTRADEVCEN 1212-1: 100 pp.