The commercial export of the land tortoises (Testudo spp.) from the territory of the former Yugoslavia: a historical review and the impact of overharvesting on wild populations

Abstract

Previous data have shown that the Former Yugoslavia had a significant role in exports of land tortoises (Testudo spp.) during the past century. In this paper we present historical exploitation and compare dynamics of the trade in land tortoises in the former Yugoslavia according to Federal Statistical Office and Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) database. Also we examine impact of long-term harvesting on the health of populations by calculating the condition index (CI) in the sample populations of the most common tortoise in the former Yugoslavia (Testudo hermanni). According to the Federal Statistical Office's records of international trade, a total of 2615 metric tonnes of tortoises (T. hermanni and T. graeca) were exported from the Former Yugoslavia within a 41-year period during the 20th century. These exports represented a total of 2.142 million specimens. The quantities of tortoises exported peaked at a value of 236 tons in 1972. Since 1929, tortoises have been exported to 19 countries. The largest importers were Germany, Italy, Belgium-Luxembourg and Great Britain. These countries accounted for 77% of the total exports. We found many discrepancies between official Federal records and CITES records for the period from 1975 onwards. Differences were found in the quantities exported, the identities of the importing counties and their relative shares of the total export of tortoises. The current optimal CI values in examined tortoises suggest a response to overharvesting through density-dependent processes. The paper discusses a current situation in tortoise farming and trade and further perspectives on conservation of tortoise populations in the region of the former Yugoslavia.