Balkan Spined Loach
Sabanejewia balcanica (Karaman, 1922)
Cobitis balcanica Karaman, 1922: Drensky, 1928: 169; Cobitis aurata balcanica Karaman, 1922: Drensky, 1951: 125; Sabanejewia aurata balcanica Karaman, 1922: Karapetkova, Zivkov, 1995: 134.
Order Cypriniformes
Family Cobitidae
Conservation status: in Bulgaria: Vulnerable VU [A1a, c], BDA-II; International: IUCN [DD], BeC-III, HD-II.
General distribution. Central and Eastern Europe.
Distribution and abundance in Bulgaria. In the past, it was recorded in the upper and middle reaches of most Danube tributaries, and in many of the tributaries of the Maritsa River. It was also recorded in the Struma River and its tributary the Rilska Reka, in the rivers Dospat and Kamchiya [1]. Later, the species was confirmed repeatedly in the rivers of the Danube basin – Iskar and its tributaries [2, 3, 4, 5, 6], Ogosta [3, 7], Vit [3, 8, 9], Osam [3] and Yantra [3, 9, 10]. It was also found in the rivers Archar and Lom [7]. Gradually, the species disappeared in the Aegean Sea rivers. Initially, it was reported in the Struma River downstream and upstream the Studena Reservoir, as well as in its tributary the Matnitsa River [5], but during the following investigations in the region it was not found [11]. In the Maritsa River basin, the occurrence of the speceis was confirmed only in the Mechka River [9], the Arda and its tributaries, and the Byala Reka [12]. In the rivers Mesta and Kamchiya, it was not confirmed [13, 14]. Recently, the Balkan spined loach has been found in the rivers Voynishka, Vidbol, Archar, Lom, Tsibritsa, Ogosta, Iskar and Vit [our data].
Habitats. The middle and upper reaches of permanent rivers with sandy-gravel bottom and fast current.
Biology. A benthic, reophilic species. The spawning period is from late April to early June. The fecundity of the females is low: about 300 eggs, which are laid directly on the stones. It feeds on benthic invertebrate animals and fish eggs [1, 15].
Similar species. The Danube spined loach (S. bulgarica). The Balkan spined loach is distinguished by the elongated body with lower depth, and by the presence of higher number of spots, smaller in size, on the sides of the body.
Negative factors. Loss of habitats, as a result of river regulation activities; water pollution; clear-cutting in the mountain regions resulting in increase of river siltation and flooding.
Conservation measures taken. The species was included in Annex II of the Biological Diversity Act (2002).
Conservation measures needed. Restriction on regulation activities and micro-hydro power development in the middle and upper reaches of the Danube tributaries; control of deforestation in the mountain regions; protection of the rivers against pollution.
References. 1. Drensky, 1928; 2. Chichkoff, 1939; 3. Drensky, 1951; 4. Paspalev, Peshev, 1955; 5. Bulgurkov, 1958; 6. Dikov et al., 1988; 7. Michailova, 1970; 8. Karapetkova, Dikov, 1986; 9. Sivkov, 1991a; 10. Karapetkova, 1972; 11. Michailova, 1965a; 12. Pehlivanov, 2000b; 13. Apostolou, 2005; 14. Karapetkova, 1974; 15. Karapetkova, Zivkov, 1995.
Authors: Tihomir Stefanov, Teodora Trichkova
