Zero of Animal Life probably about 300 fathoms



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INTRODUCTION

Undeterred by Forbes’ (1844: 170) notorious

observation “Zero of Animal Life probably about 300

fathoms”, the scientific exploration of the Levantine

bathyal biota commenced with the extensive voyages

of the Pola (1890-1893). In 1910 the Danish

Oceanographic Expedition to the Mediterranean,

aboard the Thor, sampled nine sites along the western

limits of the Levantine Sea, from Cyrenaica to

THE BATHYAL FAUNA OF THE LEVANTINE SEA



63

SCI. MAR., 68 (Suppl. 3): 63-72

S

CIENTIA


M

ARINA


2004

MEDITERRANEAN DEEP-SEA BIOLOGY. F. SARDÀ, G. D’ONGHIA, C.-Y. POLITOU and A. TSELEPIDES (eds.)



The limit of the sea: the bathyal fauna of

the Levantine Sea*

BELLA S. GALIL

National Institute of Oceanography, Israel Oceanographic and Limnological Research, P.O.B. 8030,

Haifa 31080, Israel. E-mail: bella@ocean.org.il

SUMMARY: In the present study, the fish, molluscs, crustaceans and echinoderms collected at depths between 734 and 1558

m during a series of cruises conducted between 1988 and 1999 off the coast of Israel, supplemented by a photographic sur-

vey carried out southwest of Cyprus at a depth of 2900 m, were analysed. The main objectives were to determine the faunal

composition of the bathybenthic assemblages in the southeastern Levantine Sea, and to compare them with the western

Mediterranean assemblages in order to elucidate whether general trends in their bathymetric distribution and population den-

sity may be related to environmental/geographic factors. Considering the sampling effort, the diverse gear used and the

extended period of sampling, we may assume that the low number of species and specimens recorded actually reflects a low-

diversity, low-density deep water fauna. The faunal scarcity may cause a different parcelling of the populations which is

reflected in bathymetric distributions that in many cases extend to greater depths than in the Western Mediterranean. The

Levantine bathybenthos is composed of autochthonous, self-sustaining populations of opportunistic, eurybathic species that

have settled there following the last sapropelic event. 

Key words: Mediterranean Sea, Levantine Sea, bathyal, diversity, abundance, bathymetric distribution, new records, fish,

Decapoda, Amphipoda, Cumacea, Mollusca. 

RESUMEN: E

L LÍMITE DEL MAR

LA FAUNA BATIAL DEL MAR



L

EVANTINO


. – En este estudio se analizan los peces, los molus-

cos, los crustáceos y los equinodermos recolectados a profundidades entre 734 y 1558 m, durante una serie de campañas de

muestreo realizadas entre 1988 y 1999 delante de las costas de Israel. Estas muestras se complementan con fotografías sub-

marinas realizadas a 2900 m de profundidad al suroeste de Chipre. El objetivo es determinar la composición faunística de

las asociaciones batipelágicas en el sureste del mar Levantino y compararla con las asociaciones del Mediterráneo occiden-

tal, con el fin de observar si existen tendencias generales en su distribución batimétrica y en las densidades de las pobla-

ciones, de manera que puedan ser relacionadas con factores geográficos y ambientales. Considerando el esfuerzo realizado

en muestreo, los diversos artes usados y el amplio período de muestreo, podemos asumir que el bajo número de especies y

especímenes registrado refleja realmente la baja diversidad y la baja densidad de la fauna de las aguas profundas. La escasa

fauna puede causar un distinto parcelado de las poblaciones que se refleja en su distribución batimétrica la qual en muchos

casos se extiende hacia las más grandes profundidades del Mediterráneo occidental. El batibentos levantino esta compuesto

por especies autóctonas, poblaciones de especies oportunistas auto-sostenibles y euribáticas, que colonizaron estos fondos

desde el último evento sapropélico.

Palabras clave: mar Mediterráneo, mar Levantino, batial, diversidad, abundancia, distribución batimétrica, nuevas citas,

peces, Decapoda, Amphipoda, Cumacea, Mollusca. 

*Received June 9, 2003. Accepted January 27, 2004.

sm68s3063-13  7/2/05  20:09  Página 63




Rhodes. However, as that expedition was concerned

mainly with plankton investigations, and “dredgings

were only occasionally made … the result will thus

necessarily be but poor” (Stephensen, 1915). The

Lamont Geological Observatory research vessel Vema

collected few deep benthic samples in 1958 (Barnard,

1964). Four deep-water shark species were collected

in five hauls using bottom long-line at depths of 1330-

1440 m off the Mediterranean coast of Israel in 1985

(Golani, 1987). The German research vessel Meteor

[cruise 5] in 1987, collected benthic samples at sites

between Crete and Israel at depths ranging between 95

and 4396 m during a ten-day sojourn (Janssen, 1989).

The handful of deep sea fishes gathered persuaded

Klausewitz (1989) that “this collecting trip confirmed

the paucity of the deep sea fish fauna in the eastern

basin of the Mediterranean”. The Meteor returned in

1993 [cruise 25], to collect deep-sea biota from the

region between Crete, Cyprus and Egypt at depths

ranging between 194 and 2812 m, as well as sea bed

litter (Galil et al., 1995). The fauna of Eratosthenes

Seamount, south of Cyprus, was briefly sampled by

the  Poseidon [cruise 201/2] in February 1994 (Galil

and Zibrowius, 1998). Among the faunistic explo-

rations of the Levantine bathyal, only Gilat and

Gelman (1984), and Jones in Priede and Bagley

(2000) made use of photographic equipment to

observe the deep fauna in its environment. 

The meagre number and extent of the explo-

rations prompted Fredj and Laubier (1985), in their

review on the deep Mediterranean benthos, to

declare that “...the southern part of the Levant Sea

has practically never been studied”. 

The present study analysed the data obtained

from samples collected by a box corer and a bottom

trawl fitted with a plankton net during a series of

cruises conducted between 1988 and 1999 as part of

pollution monitoring surveys by the Israel

Oceanographic and Limnological Research (IOLR)

off the coast of Israel, at depths between 734 and

1558 m, supplemented by a photographic survey

carried out southwest of Cyprus, at a depth of 2900

m. The main objectives were to determine the faunal

composition of the bathybenthic assemblages in the

southeastern Levantine Sea, and to compare them

with the western Mediterranean assemblages in

order to elucidate whether general trends in their

bathymetric distribution and population density may

be related to environmental factors. Although

restricted to a small area and to the depth range men-

tioned above, this study has significantly increased

our knowledge of the Levantine deep sea fauna.

STUDY AREA AND METHODS

The Levant Sea occupies the easternmost

Mediterranean, east of the line connecting Rhodes

and the coast of Cyrenaica. It is isolated from the

deep Atlantic waters by the topographical and

hydrological barriers posed by the shallow Gibraltar

Straits and the Siculo-Tunisian sill. The Levantine

deep water mass is distinguished by salinity and

temperature values that are higher than in the rest of

the Mediterranean (T < 13.8ºC, S < 38.74, below

700 m) (Hecht et al., 1988). The Levantine Sea is

ultra-oligotrophic (Berman et al., 1984; Krom et al.,

1991): Chlorophyll concentrations are as low as

0.4 µg l


–1

nearshore, and decrease offshore to 0.05

µg l

–1

(Berman et al., 1986; Yacobi et al., 1995).



The area investigated is located off the coast of

Israel, at depths between 734 and 1558 m. The mate-

rial was collected during monitoring surveys of two

deepwater waste-dumping sites: an acidic sludge dis-

posal site off Haifa (between 33°00’N 34°37’E and

33°01’N 34°47’E), a coal fly ash disposal site off

Hadera (between 32°38’N 34°02’E and 32°36’N

34°16’E), and a control site off Atlit (between

32°53’N 34°10’E and 32°51’N 34°23’E). The sam-

ples were collected aboard the R/V Shikmona (720

HP; 27 m), using a modified Agassiz benthic trawl

(2.3 m width and 0.9 m height), a 45 ft Marinovich-

type deep water trawl (codend mesh 6 mm) with a 0.5

mm plankton net secured atop, and a 0.062 m

2

box-


corer with an effective penetration of 40 cm (Ocean

Instruments model 700 AL) (Table 1). The samples

were preserved in 10% buffered formalin aboard ship.

In the laboratory, the samples were washed and

sieved through a 500 µm mesh, preserved in 70%

alcohol, stained in Rose Bengal and sorted. 

The photographic survey took place southwest of

Cyprus, at depth of 2900 m. A total of 80 hours of

video were recorded utilising a remote operating

vehicle (Remora 6000, Phoenix).

RESULTS

Fishes 

A total of 566 specimens identified to 31 species

were collected during the study. Four species were

new records for the eastern Mediterranean, four

species were new records for the Levantine Sea and

five species were newly recorded from the Israeli

coast (Galil and Goren, 1994; Goren and Galil,

64

B.S. GALIL

sm68s3063-13  7/2/05  20:09  Página 64



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