The IUCN/SSC Shark Specialist Group
Shark News 11: July 1998
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Shark and ray fisheries in Turkey
Hakan Kabasakal, University of Istanbul, Turkey
Because of the unusual appearance of sharks and rays, the smell
of their meat, and the religious beliefs of the Turkish people, only
limited quantities of these fish are eaten in Turkey. However,
recent drastic reductions in the stocks of traditional commercially
important sea fishes mean that chondrichthyan fishes are now
actively being considered as new opportunities for fisheries
development.
Istanbul Harbour. Photo: Paul Goriup.
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In Turkey, the main fishing areas for sharks and rays are in the
Black Sea and the northern Aegean. Fishermen use otter trawls,
purse seines, bottom long-lines and shark nets. The shark nets used
by fishermen are a form of gill net. Combinations of 12 to 20 of
these nets are set on the bottom. Each net is 200 m long by 6 m
deep, with a mesh size of 12 cm (knot to knot). Seabream and
turbot long-lines are also commonly used in the shark fishery, but
the gear is made from stronger materials.
Spiny dogfish Squalus acanthias, thornback ray Raja clavata
and smooth-hounds spp. Mustelus are the species targeted. The
first two species are commonly caught in the Black Sea. Spiny
dogfish and thornback rays are, according to Kutaygil and Bilecik
(1976), very important among the Black Sea's demersal fish fauna,
and constituted 18.1% and 5.7%, respectively, of the total demersal
catch on the Turkish coasts of the Black Sea at this time.
Thornback rays are abundantly caught on the western Black
Sea coasts of Turkey between 30 and 50 m depth (Kutaygil and
Bilecik 1979). The main fishing grounds of the large individuals
(80-110 cm TL) of spiny dogfish are the coasts of the central Black
Sea (Kutaygil & Bilecik 1977). Fishing depths for the spiny dogs
ranged from 90 m to 110 m or a little deeper.
| Annual spiny dogfish and thornback ray landings (tons) in Turkey, 1994. |
|---|
| Fishing area | Spiny dogfish | Thornback ray |
| Black Sea | | |
| Eastern part | 463 | 341 |
| Western part | 1,969 | 346 |
| Sea of Marmara | 79 | 60 |
| Aegean Sea | 129 | 165 |
| Mediterranean Sea | 240 | 326 |
| Total | 2,880 | 1,238 |
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(From 1994 Fishery Statistics, State Institute of Statistics,
Prime Ministry of Republic of Turkey.) |
(From 1994 Fishery Statistics, State Institute of Statistics,
Prime Ministry of Republic of Turkey.)
Unfortunately, we do not have detailed information on the
present status of the stock structure and population dynamics of
these chondrichthyans in Turkish seas.
Many of the smooth-hounds landed in Turkey are taken by
shark nets, particularly in the northern Aegean Sea. The lesser
spotted dogfish Scyliorhinus canicula is another shark caught in
the Sea of Marmara and the northern Aegean Sea. The length of
this species rarely exceeds 50 cm and it is therefore usually
discarded by fishermen.
Large sharks are not subjected to a targeted commercial fishery
in Turkey, but they are accidentally caught during the fisheries for
other commercially important species. The commercial swordfish
long-line fishery in the Gulf of Antalya (on the Mediterranean
coasts of Turkey) takes thresher sharks Alopias vulpinus incidentally.
The bycatch of these vessels is mostly landed for export. Purse
seine vessels only rarely land bluntnose sixgill shark Hexanchus
griseus bycatch in the Sea of Marmara.
| Annual landings (mt) of sharks and rays in Turkey, 1989-1994. |
|---|
| Species | 1989 | 1990 | 1991 | 1992 | 1993 | 1994 |
| Smooth-hounds |
| ( Mustelus spp.) | 5,140 | 1,715 | 2,292 | 2,404 | 1,436 | 2,880 |
| Angelfishes |
| ( Squatina spp.) | 25 | 34 | 17 | 13 | 13 | 15 |
| Skates |
| ( Raja spp.) | 2,028 | 1,056 | 1,209 | 1,557 | 1,557 | 1,238 |
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(From: FAO yearbook, Fishery statistics (Catches and
landings), 1994.) |
The meat of the spiny dogfish and smooth-hounds is typically
processed (smoked or salted) for export, or marketed as fresh
whole carcasses. Fins and oil-filled livers of sharks are processed
and exported, but no data are available on production quantities.
Rays and skates are typically processed as wings, and marketed
frozen and without skin.
Our knowledge of the life history parameters (i.e. age and size
at first maturity or breeding season) and the population dynamics
of sharks and rays in Turkish seas is very scarce. Furthermore, no
management measures have been implemented for sharks and
other species of chondrichthyan fishes. These two points are
possibly the major factors hindering the development of a
sustainable chondrichthyan fishery in Turkey.
| Exported chondrichthyan production of Turkey, 1994. |
|---|
| Product | Quantity | Value |
| | (kg) | (US$) |
| Shark fillets, smoked | 2,145 | 2,698 |
| Spiny dogfish, fresh/chilled | 8,423 | 21,222 |
| Lesser spotted dogfish,fresh/chilled | 220 | 518 |
| Spiny dogfish, frozen | 33,680 | 66,590 |
| Spiny dogfish and lesser spotted dogfish, frozen fillets | 45,640 | 69,827 |
| Shark fillets, frozen | 66,950 | 122,140 |
| Shark fillets, fresh/chilled | 25,864 | 50,823 |
| Shark fillets, smoked | 7,361 | 35,810 |
| Shark fillets, salted | 130 | 377 |
| Shark fillets, processing type unknown | 2,790 | 4,464 |
| Total | 193,203 | 374,469 |
| (From 1994 Fishery Statistics, State Institute of Statistics,
Prime Ministry of Republic of Turkey.) |
References
Kutaygil, N., and Bilecik, N. 1976. Observations sur les principaux produits
démersaux qui sont pêchés sur les côtes Turques de la mer Noire. Rapp.
Comm. Ýnt. Mer Médit., 23, 8:75-77.
Kutaygil, N., and Bilecik, N. 1977. Recherches sur le Squalus acanthias L.
Du littoral anatolien de la mer Noire. Rapp. Comm. Ýnt. Mer Médit.,
24, 5:81-83.
Kutaygil, N., and Bilecik, N. 1979. La distribution du Raja clavata L. sur
le littoral anatolien de la mer Noire. Rapp. Comm. Ýnt. Mer Médit.,
25/26, 10:95-98.
Hakan Kabasakal, M.S.
University of Ýstanbul, Fisheries Faculty,
Department of Marine Biology,
Ordu cad., No. 200, Laleli 34 470,
Ýstanbul, TURKEY
Fax: (90) 212 514 03 79
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