Data on the largest specimens of Testudo graeca ibera Pallas, 1814 found in Bulgaria with five new records

Very large specimens of T. graeca ibera were found in Bulgaria, but mostly in the 20th century. Presently, such tortoises are almost absent in the country. Here we summarise data about the largest spur-thighed tortoises registered in Bulgaria and provide information about five new large-sized individuals. We also draw attention to the fact that large specimens can hardly be found in the country today and discuss some possible negative effects of the extinction of these specimens on the existing populations. The maximum straight carapace length of the largest T. graeca ibera ever found in Bulgaria was ≈ 389 mm, but the maximum straight carapace length of the newly measured tortoises was 298 mm. Considering the rarity of such tortoises in the country today, the genes that determine the potential to reach larger sizes may gradually disappear. Thus, the institutions responsible for the conservation of nature should pay attention to areas where the presence of large-sized individuals has been established. This might help preserve the natural genome of T. graeca ibera in the country and therefore the existence of large individuals

First survey on the invasive Pond slider (Trachemys scripta) in Bulgaria: historic development and current situation

Crvenouha kornjača (Trachemys scripta) postala je popularni ljubimac u Bugarskoj od 1990. Kroz godine sve veći broj jedinki zabilježen je i u divljini. Iako su negativni učinci na izvornim kornjače su opsežno studirao negdje drugdje, nema posebne studije (osim kratkih izvješća) obratili invaziju T. scripta u Bugarskoj. Ova studija se temelji na više od 25 godina praćenja na terenu i predstavlja prvi izvor detaljne informacije o raspodjeli Pond klizača u Bugarskoj. Ukupno 293 UTM (10 × 10 km) kvadrata sa staništa pogodna za slatkovodne kornjače ispitano. Prikupili smo 64 zapisa za 173 osoba, od 19 UTM kvadrata. Od svih promatranih osoba, samo dvije su od nominirati podvrste - ostatak pripada T. Š. elegans. U našem istraživanju je uočeno samo jednoga djeteta. Do danas nije uspješno leženja zabilježena, iako su registrirani uspješni overwinterings. Mi smo razgovarali o raznim mjere ublažavanja koje se moraju brzo pokrenut ograničiti buduće izdanje Ribnjak klizača i za uklanjanje ne-izvornih uzoraka s bugarskim ekosustava. Akcije su zahtijevali posebno da se izbjegne potencijalne epidemiološko događaja uzrokovanih parazitima s vrlo smrtonosnim učinkom na autohtonim vrstama. Takve pojave potencijalno mogu imati veći utjecaj na autohtone vrste kornjača jezerce od raznih oblika natjecanja s T. scripta.Pond sliders (Trachemys scripta) have become a popular pet in Bulgaria since 1990. Through the years a number of released specimens were observed in the wild. Although the negative effects on native turtles have been studied extensively elsewhere, no specific studies (besides brief reports) have addressed the invasion of T. scripta in Bulgaria. The present study is based on over 25 years of field monitoring and represents the first source of detailed information on the distribution of the Pond slider in Bulgaria. A total of 293 UTM (10×10 km) squares with habitats suitable for freshwater turtles were surveyed. We collected 64 records for 173 individuals, from 19 UTM squares. From all observed individuals, only two were from the nominate subspecies – the rest belong to T. s. elegans. In our study only one subadult was observed. To date no successful hatching has been recorded, although successful overwinterings have been registered. We discuss various mitigation measures that must be rapidly initiated to limit future release of Pond sliders and to remove the non-native specimens from the Bulgarian ecosystems. Actions are demanded especially to avoid the potential epizootic events caused by parasites with highly lethal effect on native species. Such outbreaks might potentially have greater impact on the native pond turtle species than various forms of competition with T. scripta