TRITURUS DOBROGICUS (KIRITZESCU, 1903)
DANUBE TRITON

Order Caudate Amphibious Class - Caudata Scopoli, 1777 or Urodela Latreille, 1825

Family Salamandrids or True Salamanders - Salamandridae Goldfuss, 1820

Genus Newts - Triturus Rafinesque, 1815

The Danube Triton, Triturus dobrogicus (Kiritzescu, 1903) is on of the 14 European and west Asian species of this genus. On the territory of Ukraine, it is represented by two subspecies: nominative, Triturus d. dobrogicus (Kiritzescu,1903), which is prevalent in the lower reaches of the Danube and the Dnieper (probably, the Dnister and the Bug) in Odesa and Kherson oblasts, and Triturus d. macrosomus (Boulenger, 1908), which in Ukraine is found on the territory of Pannoniyska lowland, Transcarpathia Oblast.

The length of the body of amphibians of this species averages approximately 115 mm. From close species of tritons of this group they differ in the first place through a more elongated body with a usual number of their body vertebrae of 16-17 and the Waltershtoft Index (WI is the correlation between the length of a fore limb and the span between the fore and hind limbs) is usually less than 54,0%. Palatine teeth look like two elongated lines which meet in the front and part in the back. The front of the nose is somewhat rounded, the eyes are small; the head is connected with the body through a slight narrowing of the body. The tail is somewhat thicker on the sides. Swimming membranes on the fore limbs are non-existent and on the hind limbs they are weakly developed at the base of the digits. Skin is coarse-grained, the general background of its coloration consists of darkly spotted brown and black colors, the lower part of the head, neck and further the sides are scarcely spotted with white. The belly is bright red and orange with large black spots which often blend and thus sometimes create the effect of development of red and orange spottiness on the black background. During the mating period, males develop a serrated crest in the upper part of the body, which runs from the head to the base of the tail, then stops and resumes further along the upper and lower tail. Upon the spawning season, the crest decreases abruptly though does not disappear completely (sexual dimorphism is displayed through this character and a more prominent cloaca).

Status. II Category of the Red Book of Ukraine - "endangered species"; the species is also listed in the Appendix II of the Bern Convention ("animal species under special protection").

Biotopes. The expansion of the Danube Triton on the territory of Transcarpathia is related to floodland biotopes. Here it can be found on water-meadows, swamps, shrubberies and altered anthropogenic areas. In the Danube and Dnieper deltas, it was found in steppe biotopes: floods of small rivers, water pits and overflow lands. According to special research, in Transcarpathia it is found in areas not lower than 125 m above sea level, and in the Danube lowlands - up to 50 m above sea level.

Number and Tendencies to Change. According to the records, in Transcarpathia its number reaches 5-12 ones per 100 m of the coast line or 1 triton per 1-50 m2 of a water body area. According to another research, the density of its population here makes up in some places 60 tritons per 100 m of the coast line and in the Danube lowlands - up to 150 (the vicinity of the town of Vilkovo). In May 2002, the number of tritons of this species in a 20 m² water body amounted to 0.4 ones/м².

Biological Characteristics. Winter hibernation in Transcarpathia ends around March (sometimes in late February). Data about reproduction is fragmentary and is limited to information of the beginning of the mating season which falls on March-April. Mating games happen in slow and still water bodies, in canals and ditches. The female lays each spawn berry separately wrapping it in leaves of aquatic plants. The majority of larvae complete their metamorphosis at the end of July – August though some of them remain in water until October. It is probably characteristic of females to skip mating seasons. It is not improbable that the Danube Triton is more resistant to higher temperatures, which allows it to live in more southern parts of the natural habitat (as compared to the Cristate Triton) and this also determines its expansion in Transcarpathia lowlands. After the reproduction season, these tritons leave water and remain active almost till the end of October. In winter, they use practically the same shelters as Cristate Tritons: holes, hollows, moldering tree stumps etc. Probably, these animals can hibernate in water as well. They become reproductively mature at the age of approximately 2 years old, the maximum life span - 10 years.