Megalofonou et al .: Incidental catch and estimated discards of pelagic sharks in the Mediterranean Sea 621 



Figure 1 



Map of the Mediterranean Sea, showing the nine study areas used for sampling sharks during 

 1998-2000. l = Alboran Sea. 2 = Balearic Islands area, 3 = Catalonian Sea, 4=Tyrrhenian Sea, 

 5 = Straits of Sicily, 6=Adriatic Sea, 7 = Ionian Sea, 8=Aegean Sea, and 9 = Levantine basin. 



target species because their current low market value 

 now appears to be increasing. Many of the data re- 

 quirements of pelagic shark assessment are similar 

 to those for assessing other highly migratory species: 

 knowledge of stock structure, age and growth rates, 

 natural mortality rates or fishery statistics. However, 

 there is scant information about either the population 

 biology or the catch levels of most incidental species. 

 Primary literature on pelagic shark incidental catch 

 in the Mediterranean Sea is rare and relates only to 

 subareas that are not studied in a coordinated manner 

 (De Metrio et al., 1984; Filanti et al., 1986; Buencuerpo 

 et al., 1998; Di Natale, 1998; Mejuto et. al., 2002). IC- 

 CAT reports on pelagic shark catch show great annual 

 variation in catch statistics and are fragmented because 

 not all countries submit data for the entire time series. 

 Catches of Selachii reported by FAO statistics for Spain, 

 Italy, and Greece in the Mediterranean amount to 4209 

 metric tons in 2000, but include pelagic and benthic 

 sharks, skates, rays, and chimaeras together. 



Given the scarcity and heterogeneity of the available 

 data, an international project was established (Megalo- 

 fonou et al. 1 ) to collect fishing and biological data with 

 standardized methods from all commercial fisheries of 

 the European countries that catch pelagic sharks in the 

 Mediterranean. This article presents the results of the 



Megalofonou, P., D. Damalas, C. Yannopoulos, G. De Metrio, 

 M. Deflorio, J. M. de la Serna, and D. Macias. 2000. By- 

 catches and discards of sharks in the large pelagic fisheries 

 in the Mediterranean Sea. European Union Project 97/50 

 Directorate General XIV/C1, 336 p. Directorate-General 

 for Fisheries and Maritime Affairs, European Commission, 

 Rue Joseph II, 99, B-1049 Brussels. 



investigations carried out by observers at landing sites 

 and onboard fishing vessels that target swordfish and 

 tunas with longlines and driftnets. The main objective 

 of this study was to analyze shark incidental catch and 

 discards and to provide information on species composi- 

 tion, distribution, and abundance. The status of each 

 shark brought on board (alive, dead, or damaged) and 

 the disposition of sharks caught on some vessels (kept 

 or discarded) were examined by using onboard obser- 

 vations to obtain essential data for effective fisheries 

 management. 



Materials and methods 



Sampling areas 



The Mediterranean Sea is a semi-enclosed area with 

 pronounced oligotrophy in the surface waters due to 

 small amounts of nutrient discharge from the land. The 

 shallow and narrow Strait of Gibraltar connects it to the 

 Atlantic. It consists of two nearly equal-sized basins, the 

 eastern and the western basin, connected through the 

 narrow and shallow Straits of Sicily. A network of sam- 

 pling ports throughout the Mediterranean was estab- 

 lished in order to cover a wide range of fishing grounds, 

 fleets, and gears. The sampling areas, shown in Figure 

 1, were the following: the Alboran Sea (1), the Balearic 

 Islands area (2), the Catalonian Sea (3), the Tyrrhenian 

 Sea (4), the Straits of Sicily (5), the Adriatic Sea (6), the 

 Ionian Sea (7), the Aegean Sea (8), and the Levantine 

 basin (9). Researchers from Greece, Italy, and Spain 

 were involved in data collection concerning incidental 

 catch of pelagic sharks in the Mediterranean Sea. 



