Stone Loach
Barbatula barbatula (Linnaeus, 1758)
Cobitis barbatulus Linnaeus, 1758: Kovatcheff, 1923: 96; Cobitis barbatula Linnaeus, 1758: Morov, 1931: 65; Noemacheilus barbatulus (Linnaeus, 1758): Karapetkova, Zivkov, 1995: 130.
Order Cypriniformes
Family Balitoridae
Conservation status: in Bulgaria: Vulnerable VU [B2a,b (i, ii, iv)]; International: IUCN [DD], BeC-III.
General distribution. In almost all of Europe, excluding the northernmost and the southern regions. In the north, it reaches the basin of the Baltic Sea, and in the east, the Kolima River in Siberia.
Distribution and abundance in Bulgaria. In the past, the species was recorded in the upper and some of the middle reaches of most Danube tributaries: Ogosta [1, 2]; Iskar River and its tributaries Panega, Blato, Malak Iskar, Palakariya and Bistritsa [1, 2, 3, 4, 5, 6]; Vit River near Teteven [1, 3]; Osam River and its tributaries Beli Osam and Cherni Osam [1, 2, 3]; Yantra River and its tributary Vidima [1, 2]. It was also recorded in the Kamchiya River basin: the Rakovska River near Zheravna and the Luda Kamchiya River near Ichera [7]. Later, the species was found in the rivers Nishava and Iskretska [8], Palakariya [9], Iskar near Samokov, and the rivers Archar, Tsibritsa and Cherni Vit [10]. It was introduced to the Dospat Reservoir [11]. It was also found in the Vacha River of the Aegean Sea drainage basin [10]. As early as the 1970s, its range started to decline and the species disappeared from the rivers Yantra and Kamchiya [12, 13]. Its occurrence in the Osam River is not confirmed. At present, it is found in the rivers Nishava, Vidbol, Archar, Tsibritsa, and the upper reaches of the rivers Lom, Ogosta and Vit [our data].
Habitats. It inhabits the upper and partly the middle reaches of permanent rivers with sandy and gravel bottom, and cold, fast-flowing water.
Biology. A typical reophilic species. It reaches sexual maturity at the age of 2-3 years. The spawning occurs in the period April-May. Eggs are laid among stones, where they develop for about 40 days. The fecundity of females ranges from 500 000 to 800 000 eggs. It feeds on benthic invertebrate animals, mainly during the night. The life span is 8 years [1, 14].
Similar species. The Struma loach (Barbatula bureschi), from which it is differentiated by the truncated caudal fin (in the Struma loach it is deeply notched).
Negative factors. River regulation by dams, barrages and weirs; deforestation (especially in the mountain regions); water pollution.
Conservation measures taken. None.
Conservation measures needed. Imposition of restrictions on the construction of barrages and weirs, as well as of micro-hydro power development in the upper reaches of the Danube tributaries; control of deforestation in the mountain regions; protection of the rivers against pollution.
References. 1. Drensky, 1928; 2. Drensky, 1951; 3. Kovatcheff, 1923; 4. Chichkoff, 1939; 5. Paspalev, Peshev, 1952/1953; 6. Bulgurkov, 1958; 7. Chichkoff, 1934; 8. Michailova, 1970; 9. Dikov et al., 1988; 10. Sivkov, 1991; 11. Zivkov, 1987; 12. Karapetkova, 1972; 13. Karapetkova, 1974; 14. Maitland, 2000.
Authors: Tihomir Stefanov, Teodora Trichkova
