The status of marine mammals and their interaction with fisheries along the Central Turkish Aegean coasts

This study was carried out to assess the distribution and strandings of marine mammals as well as their operational interactions with the fisheries in the central Turkish Aegean national waters. Within this context, the general scopes of the study were 1. inquiries with the questionnaires among the fishermen at the fishing ports located between Ayvalık on north and Didim-Taşburun on south and namely Ayvalık, Dikili, Foça, Urla, Dalyanköy, Sığacık, Kuşadası and Taşburun between 11 November 2003 and 24 November 2004, and 2. assessment of the stranding events collected opportunistically between 1993 and 2004. For the questionnaire applications, while at least 30 % of the professional artisanal fishermen were inquired at the each fishing port, in decreasing order 32 %, 31 % and 27 % of the entire fleet of seine, purse-seine and trawl fishermen operating in the study area were inquired. When categorised, the questionnaires were assessed by the artisanal, trawl, purse-seine and seine fishermen with a total of 2.643 (n=112), 544 (n=25), 628 (n=26) and 371 (n=16) man-years experience respectively. According to decreasing reporting frequency, Tursiops truncatus had an increasing occurrence tendency on the north of Çeşme, Stenella coeruleoalba in the south of Çeşme and Delphinus delphis in the North Aegean Sea, and Phsyeter macrocephalus at the entrances of Kuşadası and Saroz Gulfs. Moreover, the cetaceans species rarely reported were Grampus griseus, Mysticete, Orcinus orca, Phocoena phocoena, Ziphius cavirostris ve Pseudorca crassidens. The only pinniped species Monachus monachus was reported to have concentrated between Foça and Sığacık. In response to questionnaires 86 % fishermen reported to have a certain degree of interaction with marine mammals. When reported cetacean interactions including encounters around fishing operation area, depredations, driven fish from fishing gears away and economic loss taken into consideration, the most affected fishermen in decreasing order were purse-seine, artisanal, seine and trawl fishermen. It was believed that depredation on fishing gear was made by Tursiops truncatus, Delphinus delphis and Monachus monachus. According to fishermen reports it is estimated that 180 Cetacea were by-caught from 2003 to 2004, and these were happened during interactions with mainly purse-seine ? this is the first marked affect of this fishery in the Mediterranean Sea ? and artisanal fishermen, and with a minor contribution of trawl fishermen. Tough all these negative reports, fishermen claimed that instead of marine mammals the main responsible ofdepletion of fish stocks was the fishery sector. However, they have been cautious in their approach for the conservation of marine mammals and showed a tendency in favour of culling.