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T-PVS (99) 73

Up-date Report and Review of the Status of the Nile soft-shelled Turtle, Trionyx triunguis, in Turkey. Report for the 19th Meeting of the Standing Committee of the Convention on the Conservation of European Wildlife and Natural Habitats (Bern Convention). Report prepared by an independent wildlife consultant commissioned by MEDASSET The Mediterranean Association to Save the Sea Turtles September, 1999

The setting The Nile soft-shelled turtle, Trionyx triunguis, occurs in the eastern Mediterranean, where it is seriously threatened. It was included in Appendix II of the Convention on the Conservation of European Wildlife and Natural Habitats in December 1996. The strongest populations in the Mediterranean are found in Turkey, with additional populations occurring in Israel, Egypt, Syria and the Lebanon (plus a single record in Greece). Already in 1991, the Standing Committee of the Convention on the Conservation of European Wildlife and Natural Habitats recommended that the Government of Turkey ensures protection of all important populations of Trionyx triunguis (recommendation no. 26, 6 December 1991). During a progress review in 1994, Turkey reported both achievements and difficulties in putting this recommendation into practice. The Group of Experts subsequently decided that recommendation no. 26 should be still valid and should be considered a national priority. The Trionyx issue was again on the agenda of the Standing Committee Meetings in 1996 and 1997, but as no adequate progress was shown in the protection of this species, MEDASSET commissioned an independent wildlife expert in 1998 to carry out a field survey in Turkey and to review conservation needs and progresses. As the report was inadequately discussed in the 1998 Standing Committee Meeting, and no conclusion as to open a file on this species was drawn, MEDASSET continued its efforts in assessing the status and conservation needs of this species in the Mediterranean in 1999.

Population Status During a new field survey carried out by MEDASSET in summer 1999, two formerly unknown population were found: !

Mouth of Aksu River and Acisu (east of Antalya): Whereas soft-shelled turtles are only rarely found in Aksu and the nearby sea, they occur regularly in the lower course of Acisu which is situated some 1.5 km to the west of Aksu. Acisu is a small, somewhat brackish water body close to the sea. It is also called Üzlü or Kundu in its upper course, and has no regular outlet to the sea; during most times of the year, sand dunes close up the connection between the river and the sea. The area where soft-shelled turtles are found is relatively small, about 1 km long, and situated next to the sea. There are interactions between the turtles and fishermen who come to Acisu for fishing. Fishermen reported that soft-shelled turtles are destroying fishing nets, but they also claimed that they do not harm or kill them. According to local fishermen, soft-shelled turtles of all sizes occur, indicating that the species reproduces here. There are two tourist installations (one luxury hotel and a summer facility of the Turkish Ministry of Justice) between Aksu and Acisu; it appears that they do not harm the turtle populations.


River mouth of Köprü River (Köprü Çayi) and Acisu (west of Manavgat): The population of soft-shelled turtles in Köprü River and the nearby Acisu seems to be smaller than in Aksu/Acisu. In the lower course of Köprü River, soft-shelled turtles were reported by fishermen to occur rarely, although the lower river course provides suitable habitats including mud, sand and shingle banks, oxbows, islands, etc. The occurrence of soft-shelled turtles in the nearby Acisu

may also be only occasional. Anglers interviewed along the river were not aware that softshelled turtles live there. It should be noted that the name Acisu is applied to both water bodies, to the one to the west of Aksu, and to the one to the west of Köprü Çayi. According to our current knowledge of the occurrence of soft-shelled turtles in Turkey, the populations can now be classified as follows: Class I: Largest population with the highest conservation priority


Class II: • Relatively large populations which are in strong • need for conservation • • •

Dalyan Aksu/Acisu Anamur Göksu Cukurova (Ceyhan, Seyhan, Tarsus/Ber-dan: exact status unclear).

• • • •

Patara Fethiye (information insufficient) Köprü Cayi/Acisu Bozyazi (status unclear, latest information from 1988) Orontes (Asi) River (status unclear, no recent information)

Class III: Relatively small populations, but conservation required for the survival of the species

Recommendations for Conservation and Management The following chapter lists those recommendations already brought up by MEDASSET in 1998, and additional recommendations for the newly found Trionyx populations. Furthermore, plans for the construction of a marina in Dalaman were rumoured but confirmation is required. A marina would seriously threaten the largest population of soft-shelled turtles in the Mediterranean. Regarding the DALAMAN POPULATİON, it is recommended that the Government of Turkey: •

avoids any tourist and other development of the beach around the mouth of the outlet of Kükürt Gölü into the sea, especially the construction of a marina.

takes immediate steps to stop the discharge of waste water from the Incebel summer village into Kükürt Gölü, thus avoiding further eutrophication of the lake.

cleans the most polluted parts of the lake through an artificial increase of the circulation of the water of the lake (prepare a hydrological feasibility study prior to practical action).

takes care that the road along the north-eastern shore of Kükürt Gölü does not harm the softshelled turtle population through disturbance (no up-grading and no repair of the road, no opening of the closure to Incebel summer village).

considers to take, if appropriate and feasible, legal action against the owners and managers of Incebel summer village, as they pollute the natural water bodies around the summer village.

immediately stops all kind of fishing (with nets, lines, guns, and dynamite) within Kükürt Gölü, Kargin Gölü, and in Taslicay.

stops the ongoing construction of buildings on the peninsula south-west of Incebel summer village, between Kükürt Gölü and Taslicay channel, and within the coastal wetland to the south of Kükürt Gölü.

strictly limits the usage of boats in Taslicay channel between Incebel summer village and the sea.

rehabilitates and creates nesting habitats (which may also serve as basking sites) through: ⇒ clearance of the sand dune in the south-east of Kükürt Gölü from vegetation. An area where soft-shells can easily approach the dune (clear the scrub between the dune and


the water, if necessary) should be selected, and an area of some 20x5 m of blank sand dune should be provided. ⇒ widening of the southern arm of Kükürt Gölü towards the beach and clearing it of vegetation. ⇒ accumulation of sand in areas which are secure from human disturbance, and where soft-shells may lay their eggs. Possible candidate areas for the creation of artificial nesting sites are the peninsula between Kükürt Gölü and Taslicay channel, and some areas on the northern shore of Kükürt Gölü, and at the northern edge of Kargin Gölü. All rehabilitation measures should be carried out under scientific supervision, and after preparation of a feasibility study. It is particularly important to avoid any habitat destruction and significant disturbance through the proposed measures. •

makes sure that the interchange between the sub-populations of Kargin Gölü and Kükürt Gölü is always possible (keep the connection of Kargin Gölü with Taslicay open from vegetation and do not close it with fishing nets).

declares Kükürt Gölü, Kargin Gölü and adjacent wetlands a protected area, and monitor the effectivenes of protection measures on a regular basis.

Regarding the DALYAN POPULATİON, it is recommended that the Government of Turkey: •

initiates a scientific study of the impact of tourist activities on the activity pattern of soft-shelled turtles.

supports the assessment of the population size and a survey on the spatial distribution of the population within the Köycegiz/Dalyan wetland complex.

closes the dead arm of the Dalyan River near the thermal springs for boats and establishes thus an area into which soft-shelled turtles may escape from the continuous disturbance through the heavy boat traffic, and which they may use for basking and mating.

considers the closure of other areas for boats once the results of the study on the spatial distribution have become available.

considers the establishment of artificial nesting habitats by depositing sand in certain areas along the shores of Dalyan River (prepare feasibility study prior to practical action).

immediately stops boats from landing outside the already established mooring site in the lagoon to the rear of Dalyan beach.

prohibits people walking on the rear side of the sand spit which separates the Dalyan estuary from the sea outside the already established mooring site.

cleans the shores of the lagoon to the rear of Dalyan beach of litter.

integrates nest protection measures against natural predators into any programme which is carried out for the protection of marine turtles on the Dalyan beach.

strictly enforces the limit of speed boats in the Dalyan River and the estuary.

Regarding the PATARA POPULATİON, it is recommended that the Government of Turkey: •

initiates a population assessment and a survey on the spatial distribution within the Patara area.

considers the flattening of the banks of the channel at a few places. This would provide upstream nesting habitats, and may attract soft-shells to nest at a rather safe place rather than at the mouth of Esen River with continuous tourist activity.

Regarding the newly found populations at AKSU/ACİSU and KÖPRÜ CAYİ/ACİSU, it is recommended that the Government of Turkey: •

initiates a survey of the spatial distribution and movements within both areas in order to demarcate the habitats.

avoids any further development of the river banks.

establishes protected areas around these sites.


Regarding the OTHER POPULATİONS İN TURKEY, it is recommended that the Government of Turkey: •

initiates and supports a complete survey of possible areas where populations of soft-shelled turtles may exist.

assesses the impact of killing soft-shelled turtles by fishermen on the population.

takes steps against the killing of turtles by fishermen through awareness-building among them.

General Considerations Taking into account that the Nile soft-shelled turtle is under serious threat in the Mediterranean, and that so far only a few significant populations (Dalyan, Dalaman, Aksu/Acisu, Anamur, Göksu delta, Cukurova) have been identified along the Turkish coasts, conservation efforts should be concentrated on the main populations, and an appropriate stakeholder involvement should take place in order to enhance the effect of conservation measures. IT İS THEREFORE RECOMMENDED: That donor agencies, including the Commission of the European Union: • support the Government of Turkey in the implementation of these recommendations, in particular for implementing the proposed habitat rehabilitation measures. That MEDASSET and other non-governmental organisations: • provide technical expertise for assisting the Government of Turkey in the implementation of these recommendations. •

launch an international campaign in order to assist the Turkish authorities in the implementation of these recommendations.

extend the field survey started in 1998 to the Cukurova area (Tarsus, Seyhan and Ceyhan rivers) and other less known populations.

That the Standing Committee of the Convention on the Conservation of European Wildlife and Natural Habitats: • opens a file on Trionyx to monitor progress made in the implementation of the recommendations to the Government of Turkey.

References Baran, I. & M. Kasparek (1989): Marine Turtles Turkey. Status Survey 1988 and Recommendations for Conservation and Management. – WWF. Heidelberg. Gramentz, D. (1990): Beobachtungen an der Afrikanischen Weichschildkröte Trionyx triunguis (Forskal, 1775) in der Türkei. – Herpetofauna 12: 22–25. Gramentz, D. (1993): Beobachtungen und Untersuchungen zur Ethologie und Ökologie von Trionyx triunguis in West-Anatolien. – Salamandra 29(1): 16-43. Kasparek, M. (1994): Die Nil-Weichschildkröte – eine stark bedrohte Reptilienart im Mittelmeergebiet. – Herpetofauna 16: 8–13. Kasparek, M. & R. Kinzelbach (1991): Distribution and bionomics of the Nile Soft-Shelled Turtle, Trionyx triunguis, in the Eastern Mediterranean. – Zeitschrift für angewandte Zoologie 78(2): 137–159. MEDASSET (1998): Status of the Nile Soft-shelled Turtle, Trionyx triunguis, in Turkey with recommendations for conservation. - Convention on the Conservation of European Wildlife and Natural Habitats, Document T-PVS (98) 59. Yerli, S. V. & A. F. Canbolat (1998): Özel Cevre Koruma Bölgeleri’nde Deniz Kamlumbagalarinin Korunmasina Yönelik Yönetim Plani Ilkeleri. - Turkish Ministry of the Environment. Yerli, S. V., A. F. Canbolat, H. Ulug & O. Dogan (1998): Bati Akdeniz Bölgesi’nde Deniz Kampulbagalarinin Korunmasina Yönelik Yönetim Plani Ilkeleri. - Turkish Ministry of the Environment. Yerli, S. & F. Demirayak (1996): Marine Turtles in Turkey: A Survey of Nesting Sites and Status. – Dogal Hayati Koruma Dernegi, Istanbul.


T-PVS(99)73: Specific Site, Trionyx triuguis, in Turkey, update report and review.