Spread of Trachemys scripta ssp. (Testudines, Emydidae) in Serbia, with overview of possible reproduction

Abstract

The Red-eared slider (Trachemis scripta elegans) is among the world’s most invasive species, and recently its related subspecies (T. s. scripta and T. s. troostii) were also being introduced in Europe. Herein, we present data on introduction of the Red-eared slider and its related subspecies in Serbia, gathered during more than ten years. The number of reports of these turtles across Serbia almost doubled since 2015. The introductions are concentrated around Belgrade and Novi Sad cities where large populations were detected, and all cases of possible reproduction: nest digging females and findings of hatchlings. The lakes, ponds and canals in the lowland habitats (less than 100 m a.s.l.) were more vulnerable to the introduction of alien turtles – more than 73% of found alien turtles were detected at low altitudes. The two other subspecies (T. s. scripta and T. s. troostii), which emerged in the pet trade as a “substitute” after the ban on import and trade of Red-eared sliders, were also recorded at the few localities. They can hybridize with the Red-eared slider (T. s. elegans) and possibly increase its invasive potential. The stricter enforcement of the existing legislature in Serbia is needed, together with raising public awareness of the problem and eradication of established populations. Building of turtle sanctuaries is also suggested as an ethical and ecologically safe alternative for disposal of unwanted pets.