Danube Crested Newt
Triturus dobrogicus (Kiritzescu, 1903)
Molge cristatus Laurenti, 1768: Kovatscheff, 1912: 73 (part.); Triturus cristatus danubialis (Wolterstorff, 1923): Buresch & Zonkov, 1941: 214; Triturus cristatus dobrogicus (Kiritzescu, 1903): Beskov & Beron, 1964: 7.
Order Caudata
Family Salamandridae
Conservation status: in Bulgaria: Vulnerable VU [A4c], BDA-III; International: IUCN-NT, BeC-II, HD-II.
General distribution. The valleys of the basin of the river Danube, from Krems in Austria to the delta, the Danubian territories of Bulgaria, the farthest southern parts of Moldova and the lower course of the Dnieper, probably also the lower courses of the larger rivers between the Danube and the Dnieper.
Distribution and abundance in Bulgaria. It is found only along the river Danube: near Vidin, Oryahovo, Svishtov, Belene island, Ruse, Lipnik forest park, the village of Obraztsov chiflik, the village of Nova Cherna (Tutrakan region), the village of Srebarna and the city of Silistra [1, 2, 3, 4, 5, 6]. Singular individuals are known from most habitats. During 1985-2005 in the region of Kalimok (the village of Nova Cherna) during the autumn migrations from the water to the ground, hundreds of individuals were observed. There are no older data of numbers in the past. Probably, in many of the Danubian marshes and flooded areas dried up in the 1920-1960 period, populations in large numbers existed.
Habitats. Marshes, flooded areas, river mouths, irrigation and drainage canals with fresh water and ample vegetation along the Danube and some Danubian islands.
Biology. In the spring, after hectic wooing under the water, the male sticks spermatophore on underwater objects, that the female takes with its cloaka. Then it lays from several tens to several hundred slightly longitudinal eggs singularly or in small "chains" on the underwater plants. In the autumn, the newts leave the water and start living on the ground, where during the night they feed on worms, small mollusks, insects, etc. More intensive is their feeding during the "water period" of their life: on water insects and their larvae, small crustaceans, the larvae of frogs, etc. It winters on the ground in underground shelters.
Similar species. Triturus karelinii and T. cristatus. It differs from T. karelinii in the colouring of the neck: in the Danube crested newt it is amost entirely black, with scarce white and yellow dots; in the T. karelinii the neck is yellow, with dark spots. It differs from T. cristatus with the relatively shorter limbs and the markedly spotted belly.
Negative factors. Drying up many of the Danubian marshes and flooded areas in the previous century; the correction of the lowest courses of some of the Bulgarian Danube tributaries; pollution of some of the inhabited water basins with industrial and domestic waste, crude oil products, etc. The fish Percottus glenii accidentally introduced in the river Danube may have a durable negative effect on the populations of the species, which has already been proved in other countries [7].
Conservation measures taken. Some of the habitats are included in protected territories (the biosphere Srebarna reserve, Persinski marshes near Belene). Most of the wet zones near the Danube fall within the European Natura 2000 ecological network.
Conservation measures needed. Protection of the water basins close to the Danube appropriate for the existence of the species against drying up, pollution with crude oil products, pesticides for combating pests and mosquitoes, etc.
References. 1. Kovatscheff, 1903; 2. Kovatscheff, 1905; 3. Kovatscheff, 1912; 4. Buresch & Zonkov, 1941; 5. Undjian, 2000; 6. Beshkov & Nanev, 2002; 7. Litvinchuk & Borkin, 2002.
Author: Vladimir Beschkov
