Ser. Cien!. INACH 42:95-J03, 1992

U nderwater observation of Antarctic fishes and invertebrates with a note on collection and transportation techniques for

research and exhibition in the aquarium

TETSU SATOl

HIROSI SAKURAI l , AKINORI TAKASAKI l

KAKURO WATANABE2 and Y ASUO HIRAN02

ABSTRACT

Underwater observation and collection of Antarctic fishes and benthic invertebrates were conductedat the innermost part ofFildes Bay, King George lsland, South Shetland lslands, usíng scuba. Two distinct substrate types with differentfaunal compositions, namely rocky shores and clumps of submerged drifting algae, were recognized in the bay, and most animals were found associated with characteristic microhabitat on each substrate . At the shallow rocky shore, sedentary animals were found only in concave areas at the base of large rocks, where the effects of ice in winter seemed to be minimum. A wide variety of animals were unexpectedly found associated with the clumps of submerged drifting algae on the sand/mud bottom, which, asfar as we know, had not been described as an important habitat ofmarine animals in the Antarctic coast. Successful collections of various live animals were obtained and they were transported to Japan fo·r research and exhibition in the aquariums. Collection, transportation and rearing techniques of Antarctic marine life are described, and the significance of submerged drifting algae as a habitat for fishes and invertebrates in the iMer bay environment was discussed.

Key words: Antaretie marine fishes and benthie invertebrates, mierohabitat utilization, eolleetion and transportation teehniques, clump of submerged drifting algae.

Observaciones subacuáticas sobre peces e invertebrados antárticos, con técnicas de recolección y transporte para investigación

y exhibición en acuarios

TETSU SATO l , HIROSI SAKURAI l , AKINORI TAKASAKI l

KAKURO WATANABE2 y YASUO HIRAN02

RESUMEN

Mediante buceo autónomo se realizaron observaciones subacuáticas de peces e invertebrados bentónicos antárticos, en el sector más profundo de baMa Fildes, isla Rey Jorge , islas Shetland del Sur. Se reconocieron dos tipos de sustratos distintos, con diferente composiciónfaunística, tales como playas rocosas y masas de algas sumergidas a la deriva. La mayoría de los animales fueron encontrados asociados con microhábitat característicos en cada sustrato.

En las rocas poco sumergidas de la playa se encontraron animales sedentarios sólo en áreas cóncavas en la base de grandes rocas, donde los efectos del hielo en invierno parecen ser mínimos. Una amplia variedad de animaLes se encontraron inesperadamente asociados con las masas de algas a la deriva, sobre un sustrato de arena/fango el que, hasta donde sabemos, no había sido descrito como un importante hábitat de animales marinos en la costa antártica.

Se recolectaron exitosamente varias muestras de animales vivos, los que fueron transportados a Japón para

lTokyo Sea Life Park, 6 Rincaicho Edogawa-ku Tokyo , 134 Japan. 2Port of Nagoya Publie Aquarium, e/o Nagoya Kowan Kaikan, 2-1-17 lrifune Minato-ku Nagoya, 455 Japan.

95

Sato. T .. H. Sakurai. A. Takasaki. A. Watanabe and Y. Hirano

im'estigación y exhibición en acuarios. Se describen las técnicas de recolección. transpon e y crianza de f auna marina antártica \' se discute el significado de las algas sumergidas a la deri\'G, como hábitat para peces e invertebrados en el ambiente profundo de bahía Fildes.

Palabras claves: Peces e invertebrados bentónicos antárticos , utilización de microhábitats, técnicas de recolección y transporte . masa de algas sumergidas a la deriva.

INTRODUCTION

The coastal waters of Antarctica and its adjacent islands are known to have fish and invertebrate fauna characteristic ofthat region (Dayton etal ., 1970; Gon and Heemstra, 1990) . A considerable amount of knowledge on the distribution and ecology of marine organisms along the coast has been accumulated by virtue of recent advances in underwater observation techniques such as scuba diving and underwater photography (Peckham, 1964; Dayton et al. , 1970; Nakajima et al ., 1982; Numanami et al. , 1984; Hamada et al . , 1986; Numanami et al" 1986; Ekau and Gutt , 1991 ). Around the Antarctic Peninsula , Daniels and Lipps (1982) had conducted detailed analysis of habitats and distribution of fishes. Despite these efforts , however, information on natural habitats of Antarctic marine organisms still remains fragmentary , and few observations have been made on their microhabitat utilization . In addition to direct observation in the natural environment , observations in captivity (that is , in the aquarium) can provide significant information on the behavior and ecology of Antarctic marine life . However, until only several years ago , transporting and rearing techniques for Antarctic marine life had been at the early stage of development (Sakakibara and Tobayama, 1984).

Tokyo Sea Life Park (TSLP) has conducted fish collection expeditions at the coast of King George Island in 1989 and 1990 for research and educational purposes under the permission and cooperation of the Chilean Government. In total, 6 fish species and 18 species of benthic invertebrates (246 individuals) has been successfully collected using bait traps and hook and line and transported to Japan from these expeditions. Five fish species and 11 invertebrates have been maintained in the aquarium for a long period , among which three species have spawned in captivity (unpublished data). However , information on the natural habitat of collected organisms had not been obtained in these expeditions.

In 1991 , TSLP and Port of Nagoya Public Aquarium (PNPA) , a new aquarium (Public Foundation) which will open in 1992 in Nagoya City , organized a joint expedition team to conduct intensive underwater observation and collection of Antarctic marine life at King George Island in order to accumulate knowledge on the ecology of the Antarctic marine life in its natural habitat as well as to establish and enlarge captive populations for future researches. Scuba diving was conducted at two different habitats in Fildes Bay, and micro-habitat utilization of various marine organisms was recorded. In the present paper, results of collection in the 1991 expedition and characteristics of microhabitats utilized by the collected organisms are described , together with a brief note on collection and transportation techniques.

METHODS

Collection period and site

Collections and underwater observations were made at Fildes Bay King George Island , South Shetland Islands (62°S, 59°W) . from March 13 to 19, 199 1 (Fig . I). Scuba diving was conducted al the innermosl part of Fildes Bay in front of the Teniente Marsh Base of Fuerza Aérea de Chile and al ¡he easlern shore of Becerra Island . The former site (site A) was sand-mud slope down to 20 m deplh . and collections were made at deplhs from 2 to I4 m. The Iatter site (site B) was a shallow

%

Collection and transportation techniques of marine fauna

rocky shore mainly consisting of pebbles and stones, and collections were made at depths from 2 to 15 m. Additional collections were made at another rocky shore at the northem side ofthe Duran Peninsula using scuba (site C), and al so at the sand-mud bottom along the northem shore of Ardley Island (site D) using bait traps.

Collection methods

Collections and underwater observations were mainly made during scuba dives by five diverso Divers were equipped with dry suits made of 5 mm thick neoprene (Nippon Scuba), a MR-12 (Mares) or Blizzard (Sharwood) regulator and a 12liter, 200 atm tank. With these equipments, the divers could stay in the water (O to 1 degree centigrade) for up to one hour. Tanks were filled using a Utilus-l O air compressor (Bauer). Invertebrates were collected mainly by hand, and fishes were collected using hand nets and, where necessary, a fence net. Sea algae was collected by carefully removing holdfasts from substrate using a knife. In total, 21 dives were conducted.

Bait traps were used to collect gastropods and a dominant fish species, Notothenia neglecta, on the sand-mud bottom. The traps were semi-oval in shape with a size of 1 m in longer axis at the bottom and 50 cm in height (diameter of the entrance: 5 cm). Three series of traps (4, 3 and 3 traps, respectively) connected with a rope at an interval of 10 ro were set on the bottom approximately 10 to 15 m deep on March 15 and retrieved on 16.

Storage and transportation of organisms

Collected organisms were stored in lO-liter plastic bags inside 18 thermo-isolated shipping containers (162 liter capacity each) on the ground. One third to two thirds of each plastic bag's water was exchanged at least once a day . The animals were not fed during storage and transportation . Mortality during storage period was negligible.

Trasportation of the organisms was conducted using the same shipping containers. The organisms were packed in 2-ply plastic bags containing 5 to 10 liters of water together with oxygen. Then 2 to 3 of these bags were placed inside the partitioned area in the center of each container. The space surrounding the partitioned area in the container was then filIed with pieces of ice to keep water temperature between O to 1 degree centigrade. The containers were transported from King George Island to Tokyo by air via Punta Arenas, Santiago and New York. Ice was resupplied and sorne plastic bags were refilJed with oxygen at Punta Arenas. One third to all of the water in alI plastic bags were replaced with artificial sea water and ice was again resupplied at Santiago. The total transportation period from King GeorgeIsland to Tokyo was 98 hours (43 hours from Santiago to Tokyo).

RESULTS

Micro-habitat utilization of fishes and invertebrates

Two distinctive habitats with different faunal compositions were recognized in the collecting sites; cIumps of submerged drifting algae on the sand-mud bottom (site A), and rocky shores (site B and C, see Fig . 1).

At site A, the cIumps of algae were found on the bottom at depths between 4 and at least 14 m. In shalIower areas down to approximately 10m, the cIumps were mainly composed of fragments of several species of brown algae (mainly a species tentatively identified as Ascoseira mirabilis) , whereas in deeper areas below 10 m, clumps composed of a single species (Desmarestia anceps) predominated. Both algae species were of rocky shore origin, and seemed to have drifted and clumped on the bottom by tidal movement.

97

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Sato, T. , H. Sakurai , A. Takasaki , A. Watanabe and Y. Hirano

SS"SS'V .

Ki n g George l sland

Fildes Bay

o " si t e B

" siteD

........ .. : .... ··· -·.4 ......

Ardley lsland

Fig. 1. Schematic map of collection sites . See text for details of substrate types of each site .

Glyptonotus antarcticus (Order Isopoda) . Urticinopsis antarcticus (Order Actiniaria), a nemertean (Lineus corruga tus) an unidentified starfish (Order Phanerozonia) and a sea cucumber (Order Dendrochirotida) were especially abundant in the shallower clumps. A large number of G . antarcticus were found among and undemeath the algae, which may have been utilizing the algae as a refuge . U. antarcticus , a sea cucumber and an unidentified tunicate (Order Pleurogona) utilized the algae as an attaching substrate. The sea cucumber seemed to be planktivorous . A small number of large individual s of Notothenia neglecta and Lepidonotothen nudifrons and a scale-worm (Order Errantia) were also found in this habitat.

The faunal composition of the deeper clumps of Desmarestia anceps differed markedly from that of the shallower clumps. The den sities of G. antarcticus and of an unidentified starfish in this habitat were apparently lower, and sedentary or adhesive invertebrates were absent , possibly due to brushy morphology of the algae which does not serve as an attaching surface . At least three small notothenid species were associated with the algae. One of them , Trematomus newnesi hovered in water column over the algae , l to 1.5 m from the bottom, in schools of 5 to 10 individuals. As a diver approached , they quickly retreated into the algae. T newnesi have been known to feed on planktonic organisms in water column (Target , 1981), and they have al so fed on floating food in aquana at TSLP but did not pick up food on the bottom unIess they became acclimated to do so .

The sand-mud bottom around the algae clumps were densely populated with a bivalve (Latemula elliptica). Juveniles of a few fish species , incIuding those of Harpagifer antarcticus , were found in shallow areas. Juveniles of T. newnesi around 3 to 4 cm in totallength were also found in the same areas.

The rocky shores (sites B and C) were densely colonized by vanous species of sea algae , including those found in algae cIumps on the sand-mud bottom. Odontaster validus (Order Phanerozonia) and Sterechinus neumayeri (Order Echinoidea) were especially abundant in th is habita!. and many NaceUa concinna (Order Archaeogastropoda) were found in shallow zones .

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Collection and transportation techniques of marine fauna

Another species of sea cucumber (Order Dendrochirotida) and a sea slug (Order Nudibranchia) were found in low density. A tubeworm (Order Sedentaria) had a very limited micro-distribution, and was found only in concave areas at the base of large rocks, where a brachiopod species (Order Telotremata) and sponges exhibited very high density. Urticinopsis antarcticus was also found in this habitat.

Among fishes, H arpagifer antarcticus and Lepidonotothen nudifrons shared a common habitat under small pebbles. A small number of medium-sized Notothenia neglecta were found near the base of pebbles and stones.

Several species of gammarids (Order Amphipoda) were found ubiquitously in aU habitats and their density was extremely high . The species composition of gammarids has not yet been determined.

ColIection

Collection using scuba diving proved to be a very efficient method. The diversity of species and number of collected organisms increased compared to previous expeditions by TSLP, even though the collecting period was actually much shorter (in total, 201 individuals from 23 species during 12 days of collection in 1990 compared to 315 indi viduals from 30 species during 7 days in 1991). Furthermore , scuba diving from sandy beaches was possible even during blizzards when collections by the other methods would virtually be impossible.

Species composition and numbers of collected individuals are represented in Table l. Two species of fishes and six species of invertebrates had not been éollected in previous expeditions, suggesting their accesibility only by ski n or scuba diving.

Transportation

Three individual s out of five Notothenia neglecta died during transportation from Santiago to Tokyo, possibly due to accumulation of ammoniun in the water. Plastic bags with larger water capacity should have been used for larger fishes. Most individuals of starfished (sp . A) and one sea anemone died shortly after arrival in Japan . The former seemed to have suffered in poor water conditions during transportation, and the latter either by transportation or bad handling at collection . Care should be taken, especially for the former species, to lower the density during transportation. The transportation techniques for other organisms seemed to work satisfactoryly .

Rearing in the aquarium

Mortality of collected organisms in aquaria at TSLP and PNPA from March 24 to April 20, 1991 are summarized in Table 2. In general, fishes seemed to remain in good condition, although difficulties were found in planktivorous invertebrates such as a brachiopod, two species of sea cucumber, tubeworms and tunicates (though actual mortality was very low). In aquaria with c10sed circulation systems, these animals are invariably kept in a small enc10sure with a limited water flow in order to feed them efficientIy . The high density in such small enc10sures may cause significant damage over long periods of time. Further sophistication in rearing conditions is needed.

Nacella concinna seemed to be a herbivore mainly feeding on epilithic algae, and a sea slug (Nudibranchia) seemed to have very limited food repertoire . Neither species have been observed to feed on standard food items in the aquarium, and it may prove difficult to maintain them in the aquarium using conventional rearing techniques.

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Sato, T . . H. Sakurai , A. Takasaki, A. Watanabe and Y. Hirano

Table I LIST OF COLLECTED ORGANlSMS AND THEIR MAIN HABITA T TYPE

~o of

individuals

Speeies TSLP PNPA method eolleeting main habitat site type

Fishes Harpagifer antarcricus 4 Seubalh B Cnder pebbles H. antarcricus (juvenile) 4 Seubalh A Shallow sand bonom Lepidonotorhen nudifrons 9 Seubalh B Under pebbles Tremaromus newnesi 8 7 Scubalhn, fu A Deep algae cJump Trematomus sp. 2 Seubalhn , fu A Deep algae cJump Notorhenia neg/ecra 4 Trap, seubalh B, D Ubiquitous

Invenebrates Braehiopod (Teletremata) 30 Seubalh B Coneavity of rocks Lineus corruga tus 20 Trap D Ubiquitous Uricinopsis antarcticus 5 5 Seubalh A, B Surfaee of rocks and

Drifted algae Se ale worm (Errantia) 2 Seubalh A , B Under pebbles, alga Tube worm (Sedentaria) 10 Seubalh B Coneavity of rocks Clam worm (Sedentaria) 2 Seuba/h B Under pebbles Nacella concinna 15 15 Beaehlh A Rocky Littoral eh/anidora e/ongara 5 Trap D Sand-mud bottom Neobuccinum eatoni 10 Trap D Sand-mud bottom Laremu/a elliprica Seubalh A Sand bottom Sea slug (Nudibranehia) 2 Seubalh e Rocky shore Trophon nucelliformis 23 Seuba/h e Rocky shore Sero/is beddardi Seuba/h A Shallow algae cJump G/ypronotus antarcricus 20 12 Scubalh A Shallow algae clump Paraceradocus sp. (Amphipoda) 8 3 Seuba/h B Under pebbles Garnmarid sp. A (Amphipoda) 2 Seubalh B Under pebbles Odonasrer \"O/idus 7 5 Scubalh B,C Rocky shore Starfish sp. A (phanerozonia) 6 5 Seuba/h A Shallow algae cJump Starfish sp. B (Phanerozonia) 8 Seuba/h B, e Rocky shore Srerechinus neumayeri 9 7 Scubalh B Rocky shore Sea eueumber sp. A

(Dendrochirotida) 18 5 Seubalh A Shallow algae clump Sea cucumber sp. B

( Dendrochirotida) ~ Seubalh B.e Rocky shore Tunicate (Pleurogona) 4 Seuba/h A Shallow algae clump

Algae Desmaresria anceps (juvenile) 2 Seuba,h e Rocky shore Leprosomia simp/ex Seubalh e Rocky shore

TOlal number of species and indjviduals . TSLP: 213 individuals from 28 species (exeept juveniles of H. antarcricus ). P:--;PA: 102 individuals from 13 species.

Abbreviations (method 1: h: by hand . hn: hand nel. fn : fence nel. For c'o lk.: ting s i t~ and main habitat type . see text and Fig . 1 for details .

Except for a planJctivorous fish species (Trematomus newnesí) which was fed with mysids in the aquariJ. <.1.11 other fish species seemed to be omnivorous. mainly feeding on benthic organisms and detritus . These species were easily maintained in the aquarium with standard food items.

100

Collection and transportation techniques of marine fauna

Table 2 MORT ALITY OF THE COLLECTED ORGANISMS IN TOKYO SEA LIFE

PARK (TSLP) AND PORT OF NAGOYA PUBLIC AQUARIUM (PNPA)

Species

TSLP Lepidonotothen nudifrons Uticinopsis antarcticus

Laternula elliptica Paraceradocus sp. Starfish sp. A Sea cucumber sp . A Tunicate

PNPA Notothenia neglecta Lineus corrugatus Nacella antarcticus Starfish sp. A Sea cucumber sp. A

1 6

4

Mortality rate (%)

119 (11) 115 (20)

111 (lOO). 118 (13) 6/6 (lOO) 1118 ( 6) 1/2 (50)

112 (50) 1/ 13 ( 8) 1115 ( 7) 4/5 (80) 115 (20)

DISCUSSION

Characteristics of microhabitat utilization

Possible cause of death

Infection Transportation or Damage at collection Rearing condition Rearing condition Transportation Rearing condition Unknown

Transportation Accident Unknown Unknown Unknown

In general , the present results of habitat utilization among rocky shore fishes and invertebrates are consistent with previous observations (Daniel s and Lipps, 1982; Hamada et al .; 1986; Tucker and Burton, 1987) . Both at MacMurdo Sound (Dayton et al., 1972) and at Syowa Station (Nakajima et al., 1982), sedentary invertebrates were virtually absent or at least very rare in shallow areas , a phenomenon thought to be due to the effect of ice . This view was further confirmed by present observations. In very shallow rocky areas at site A, sedentary animals such as sponges, tube worms and brachiopods were found exclusively in the concavity at the base of large rocks where the effect of ice grazing seemed minimum. The dense aggregation of brachiopods also suggested the existence of certain attraction mechanisms .

.The most noteworthy feature found in the present study was the diverse fauna associated with clumps of submerged drifting algae on the shallow sand/mud bottom, which have not been described elsewhere as far as we know. The species composition of associated animals differed markedly between clumps composed of different algae species, suggesting specific association between animals and algae. In fact , a notothenioid fish , Trematomus newnesi, found associated with Desmarestia clumps on the sand/mud bottom in the present study, was also observed in a previous study to be abundant in Desmarestia beds in shallow rocky areas at Arthur Harbour, indicating close association with this algae (Daniels and Lipps, 1982). Such algae clumps provide refuges for motile animals on the open sand/mud bottom and may be utilized as a food resource for detritivores. As the descomposition rate is normally very low in cold water, these algae clumps may serve as a stable habitat for benthic animals. Therefore, the algal clumps described here seemed to playa significant role in the benthic animal community in inner bay environments. Further quantitative study on the species composition and analysis of stability of the clumps are needed.

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Sato, T. , H. Sakurai. A. Takasaki, A. Watanabe and Y. Hirano

Rearing in the aquarium as a research and educational tool

In the present joint expedition of TSLP and PNPA, individuals belonging to various species, both fishes and invertebrates , were successfully collected and transported to both aquariums, together with information and knowledge regarding the microhabitat utilization of these organisms.

As conservation of the marine environment has beco me a worldwide concem, aquariums throughout the world are more and more expected to play an important role in social education on marine biology and environmental conservation. For this purpose, the exhibitions in the aquaria should simulate a cross-section of underwater environment as precisely as possible, and information on the ecology of exhibited organisms should be provided to visitors. Knowledges pertaining to the micro-habitat utilizations of various marine organisms, as described here, is indispensable for both establishing proper exhibitions and providing information.

However, collection and observation in the present study were carried out in a very limited locality. The species collected seems to represent the fauna in shallow waters of inner bay environments , and it remains difficult to establish an exhibition duplicating deep rocky areas or exposed areas. In order to diversify exhibition, as well as to understand generalized characteristics of underwater environments around Fildes Bay, further collections and observations in various environments are needed.

Long term maintenance of Antarctic marine organisms in the aquarium can provide materials for various researches which cannot be conducted in the natural environment. As transportation and rearing techniques of many species have been well established and spawning in captivity has been observed in sorne species, data on breeding behaviour and early development of these species will be obtained in the near future. Further sophistication of rearing techniques are needed to establish breeding populations ofvarious species in the aquarium, which will contribute to our understanding of life history of Antarctic marine Jife.

ACKNOWLEDGEMENTS

We would like to express our gratitude to Instituto Antártico Chileno, Ministerio de Relaciones Exteriores, for providing research and collection permission at King George Island; the Chilean Embassy in Japan for their help and suggestion in getting permission; Servicio Nacional de Pesca, Ministerio de Economía, Fomento y Reconstrucción for issuing exportation permission for collected organisms; Operaciones Fuerza Aérea de Chile for their valuable cooperation; and Armada de Chile for providing a boat. We are deeply indebted to the New York Aquarium for their kind cooperation to transportation of collected organisms, and to Drs . Hideki Numanami, Tetsuo Iwami and Jiro Tanaka for identifying organisms and their valuable suggestions. We would like to thank the Japanese Embassy in Chile and Mr. Issac Tsunekawa for their kind hospitality and support during our stay in Chile .

REFERENCES

D":>J IELS, R.A . and J .H . LIPPS , 1982. Distribution and ecology of fishes of the Antarctic Peninsula. J. Biogeography.9: 1-9.

D.-\YTo:-;. P.K., G .. 4. . ROBILlARD, and R.T. PAINE, 1970. Benthic faunal zonation as a result of anchor ice at \1c\lurdo Sound . Antarctica. In : Holdgate, M.W. (ed .) Antarctic ecology, vol. 1: 244-258. Academic Press. London .

EKA L" , W and J . GUTT. 1991. Notothenoid fishes from the Weddell Sea and their habitat , observed by underwater photography and television. Proc . NIPR Symp. Polar Biol. 4: 36-49.

Go :-;. O . and P.e. HEE\l STRA (eds .), 1990. Fishes of the Southem Ocean. J.R.B. Smith Inst. /cthyol., Grahamstown , .¡61 pp.

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HAMADA, E . , H . NUMANAMI, Y NAITO and A. TANIGUCHI , 1986. Observation of the marine benthic organisms at Syowa Station in Antarctica using a remotely operated vehicle . Mem. Nat!. Inst. Polar Res., Spec. Issue . 40: 289-298.

NAKAJlMA, Y., K. W ATANABE and Y NAITO, 1982. Diving observation of the marine benthos at Syowa Station, Antarctica . Mem . NatI. Inst. Polar Res., Spec. Issue . 23: 44-54.

NUMANAMI, H., M . KOSAKA, Y. NAlTO and T. HOSHIAI, 1984. Distribution of camivorous benthic invertebrates in the northeastem part of Lutzow-Holm Bay, Antarctica. Mem . NatI. Inst. Polar Res., Spec. Issue . 32: 105-111.

NUMANAMI , H., E . HAMADA , Y NAITO and A. TANIGUCHI , 1986. A biomass estimation of epifaunal megabenthos by stereophotography around Syowa Station, Antarctica. Mem. NatI. Inst. Polar Res., Spec. Issue . 44: 145-150.

PECKHAM, Y. , 1964. Year-round scuba diving in the Antarctic . Polar Record . 12: 143-146.

SAKAKIBARA, S. and T . TOBAYAMA, 1984. Rearing of Antarctic marine organisms in Japan . Mem. NatI. Inst. Polar Res., Spec. Issue. 32: 103-104.

TARGET, T.E. , 1981 . Trophic ecology and structure of coastal Antarctic fish communities. Mar. Ecol . Prog. Ser. 4: 243-263.

TUCKER, M.J. and H.R. BURTON, 1987 A survey of the marine fauna in shalIow coastal waters of the Yestfold HilIs and Rauer Islands, Antarctica. ANA RE Res . Notes . 55 : 1-24.

Recibido: 22 .08 .91. Aprobado: 29. 11.91

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