Akdeniz fokunun (Monachus monachus, Hermann 1779) Kuzeydoğu Akdeniz'deki geçmişi, bugünkü durumu ve geleceği.


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Türkiye

Tezin Onay Tarihi: 2006

Tezin Dili: İngilizce

Öğrenci: Meltem Ok

Danışman: ALİ CEMAL GÜCÜ

Özet:

Status and distribution of the Mediterranean monk seal in the northeastern Mediterranean were studied between October 2003 and December 2005. In total, 7 research cruises and 8 research visits were carried out to the region in the study period. The study was generally focused on two regions. First region was mainly around the Cilicia basin in the northeastern Mediterranean where a known Mediterranean monk seal colony (the Cilician colony) inhabits. Second region was around the Gulf of İskenderun where the population status of the monk seals was unknown.In the northeastern Mediterranean, all monk seal caves especially those used for breeding have been checked for whelping and monitored during the study period. In total, 7 pups were found including one death pup in the study period. Observations of the breeding behavior of the species indicated that, whelping also takes place in 2 new caves in addition to the 39 caves already reported for the study area in the earlier studies. Increase in the number of breeding caves showed that the breeding sites of the species has been expanded within the last 5 years. The Cilician colony size was estimated as 30 individuals in 2005. Identification catalog for each individual in the Cilician colony was prepared. Finally, population viability analysis (PVA) for the Cilician monk seal colony was carried out by evaluating the vital parameters of the species, which have been collected since 1994. This analysis was carried out for both pre-conservation phase and the post-conservation phase. In post conservation phase, the survival and fecundity rate of the Cilician colony was found as 0.976 and 0.169 respectively whereas these values were estimated as 0.902 and 0.200 respectively in pre-conservation phase. It was found that there is a 26.9% risk that the monk seal colony abundance will fall below the existing level (30 individuals) at least once during the next 20 years and there is also 0.2% risk that the monk seal colony abundance will fall below 12 at least once during the next 20 years. The risk was found as 21.7% by evaluating the status of the colony in preconservation phase. It was the first PVA study for this species, in which all the parameters used in the analysis were based on the study population, instead of the congeneric Hawaiian Monk Seal. Prior to this study, although monk seals have been frequently sighted by local people in the region, status of the Mediterranean monk seals and presence of the suitable habitats for the species in the Gulf of İskenderun was unknown. Therefore, population status of the Mediterranean monk seal in the Gulf of İskenderun and suitable habitats were investigated. In total, 30 caves were discovered and 7 of them were classified suitable for the Mediterranean monk seal. In addition, a monk seal information network was established in the region in order to gain information about the species especially when the individuals are sighted (alive, injured or death). In total, 51 sighting reports were obtained from local people via the Mediterranean monk seal information network during the study period. Since there are sampling difficulties due to critical status of the Mediterranean monk seal, alternative sampling techniques were investigated in order to find answers to questions related to the monk seal colony inhabiting in the northeastern Mediterranean. For identification of the individuals, comparison of the individuals and monitoring the individuals, 3D model construction technique from photographs was tested as an alternative photoidentification technique for the Mediterranean monk seal. It was found that at least 100 reference points were needed to construct the 3D model of the monk seal.