ANNAl.ES • Ser. hist. nat. • 12 • 2002 • 1
origina! scientific paper	UDC 597.3(262-11)
received: 8. 1. 2002
CAPTURE OF A FEMALE BASKING SHARK, CETORHINUS MAXIMUS (GUNNERUS, 1765); FROM SOUTHERN TURKEY
Hakan KABASAKAL Ichíhyoíogical Research Society, Atatürk mahaliesi, Meniejoglu caddesi, idil apt., No 30, D 4, TR-Omraniye 81230 Istanbul E-mail: hakankabasakal@hotmail.com
ABSTRACT
On December 2001, a subadult female basking shark (Cetorhinus maximus) was accidentally captured in ¿i gill-net set for the bonito only WO metre s off the shore in the Gulf of Antalya (southern Turkey). This is the second confirmed record of this shark from the seas of Turkey.
Key words: basking shark, Cetorhinus maximus, Turkish seas, gili-net fishery
CATTURA Dl UNA FEMMINA DI SQUALO ELEFANTE CETORHINUS MAXIMUS (GUNNERUS, 1765) NELLA TURCH1A MERIDIONALE
SINTF.SI
Nel dicembre 2001 una femmina subadulta di squalo elefante (Cetorhinus maximus) é sfata catturata accidentalmente in un tramaglio per scombridi, ad appena WO metri dalla riva nel Golfo di Antalya (Turchia meridionale). La cattura dell'esemplare risulta essere il secundo avvistamento confermato per lale specie nei mari della Turchia.
Parole chiave: squalo elefante, Cetorhinus maximus, mari della Turchia, pesca con tramagiio
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ANNALES • Ser. Iiist. nat. ■ 12 • 2002 • 1
Nakan KABASAKAl: CAPTURE OF A FEMALE OASKlMC $1 iARK. CfJOto-ltNUS MAXIMUS <CUNNCRUS, I76S>. EROM SOUTHERN TURKEY, .SI-3J
INTRODUCTION
Basking shark, Cetorhmus maximas (Gunnerus, 1765), is the largest of all Mediterranean sharks (Quero, 1984). Most basking sharks are under 9 m in length, but some may grow to 15 m (Compagno, 1984). it is a typicaI planktivorous shark and its seasonal and regional occurrence is well correlated with zooplankton density (Sims et a/., 1997). Although local records of the basking sharks throughout the Mediterranean Sea are well documented (see, for example, Lipej ef a!., 2000 in Adriatic: Sea; Najai, 1980 in Tunisian waters; Podesta & Mag-naghi, 1988 in Italian waters), there is almost no information available concerning its presence along the coast of Turkey. The only previous local record of the basking shark is from Gulf of Iskenderun (eastern Mediterranean coast of Turkey) (Kideys, 1997). Therefore, it is not clear whether the occurrence of the basking shark in the seas of Turkey is incidental or exhibits a seasonal regularity.
in ecological terms, the basking shark is considered a typical 'k-selected species' because of its slow rates of growth, attaining the first maturity at a very late age and
22* 24" 26' 28*
_i__i_____i________i__
giving birth in very small numbers. Parker & Stolt (1965) suggest a 3.5 years gestation period for the basking shark. It is therefore one of the shark species most vulnerable to over-fishing and today it is one of the threatened species of elasmobranchs mentioned in the lljCN Red List of Threatened Animals (Fowler, 1996), Due to the above reasons, local populations of basking sharks should be monitored carefully.
The present paper aims to make a contribution to the knowledge of sharks occurring in the seas of Turkey.
MATERIAL AND METHODS
A female basking shark has been accidentally captured on December 2001 in 3 gill-net set for bonito only 100 m off the shore (depth nearly 7 m) in the Gulf of Antalya (36"32'01", N 30°31'02" E; Fig. 1). Body-measurements were taken with a hand meter following the guidelines by Compagno (1984). Unfortunately, the shark has been immediately sold at the fish market and therefore it was not possible to examine the internal organs of the specimen.
30" 32° 34° 36°
__i_i_t..........*
Fig. 1: Location of the sampling site (it) in the Culf of Antalya. Si. 1: Lokacija vzorčišča i*)v Antalijskem zalivu.
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ANNALES • Ser. Iiist. nat. ■ 12 • 2002 • 1
Hjk.11% KABASAKAL: CAPTURf OF A FEMALE BASKING SHARK, CI'tORHIKUS MAXIMUM(CUNNERlIS. 1765t, FROM iOUTHtSN TURKEY. 31-3*
Tab. 1: Body measurements of the female basking shark (Cetorhinus maximus), accidentally captured in the Culf of Antalya.
Tab. 7: Mere samice morskega psa orjaka (Cetorhinus maximus), naključno ujete v Atitalijskem zalivu.
Measurement	cm	% of TL
Total length	600	-
Girth in front of the 1!1 dorsal fin	205	34.16
Length of the 1* dorsal fin	98	16.33 i
Length of the 2!'d dorsal fin	60	10
Distance between the 1" dorsal and pelvic fins	97	16.16
Dorsal caudal margin	145	24.16 |
Ventral caudal margin	90	15 j
Preorbital length	45	7.5 i
RESULTS AND DISCUSSION
This specimen of the basking shark entangled in a gill-net in the Gulf of Antalya is the second confirmed recording of this species from the seas of Turkey. Body measurements of the specimen are given in Table i.
Basking sharks are known to become mature when reaching the length between 8.1 and 9.8 m {Compagno, 1984). Therefore, it could be assumed that the female basking shark (6 m TL) captured in the Gulf of Antalya is a subadult individual.
Although Parker & Boeseman (1954; sensu Sims et al., 1997) proposed that basking sharks migrate from coastal to deep waters in September and October, no information is available to explain the reasons for the winter occurrence of this female basking shark in the shallow coastal waters. However, migrations of the basking sharks in the seas of Turkey, particularly in the coastal waters where an intensive gill-net fishery is carried out, should be determined in detail for reducing the possible impacts of by-catching on this vulnerable shark.
SAMICA MORSKEGA PSA ORJAKA CETORHINUS MAXIMUS (GUNNERUS, 1765),
UJETA V VODAH JUŽNE TURČIJE
Hakan KABASAKAL Icblhyological Resoatch Society, Ataturk inahallesi, Mentejoglu c.addesi, idil apt., No 3£>, D 4, TR-Umraniye 81 230 Istanbul E-mail: h3kankabdsakai@ttotrnail.corn
POVZETEK
Decembra leta 2001 se je v stoječo mrežo palamidarico, postavljeno 100 m od obrežja v Antalijskem zalivu (južna Turčija), ujela samica morskega psa orjaka (Cetorhinus maximus). To je drugi potrjeni zapis morskega, psa orjaka iz turških voda. Glede na njeno celotno dolžino (6 m) gre bržkone za skoraj odrasel osebek. Avtor meni, da bi bilo nujno skrbno spremljanje morskega psa orjaka v turških vodah, da bi se zmanjšal vpliv v mreže naključno ujetih osebkov na tega ranljivega morskega psa.
Ključne besede; morski pes orjak, Cetorhinus maximus, turške vode, ribolov s stoječimi mrežami
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ANNALES • Ser. Iiist. nat. ■ 12 • 2002 • 1
Mak.ii! kABASAI-;,-v.. CAPTURE OF AFtMALï BASKINC SHARK, CCTOIO(INUSMAXIMUSCGUNHERU5, I 76», TROM SOUTHERN fURK'tY, Jt-54
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