Nerophis ophidion (Linnaeus, 1758)
Conservation status: in Bulgaria: Endangered EN [B2b (i, ii)].
General distribution. The species inhabits the British Isles and the Atlantic coast from Trondheim (Norway) to Northern Morocco, the Mediterranean and adjacent seas: the Adriatic Sea, the Aegean Sea, the Sea of Marmara and the Black Sea.
Distribution and abundance in Bulgaria. In the past, it was found everywhere along the Bulgarian Black Sea coast, in the rivers Kamchiya, Ropotamo, Veleka and in some of the coastal lakes – Durankulak, Varna, Beloslav, Burgas and Mandra [1, 2, 3, 4, 5]. Recently, single specimens have been caught in the region of Cape Kaliakra, Varna Bay and the Dyavolska River [6, 7, 8].
Habitats. A phytophylic species. It stays close to the shore, usually amidst the eel-grass fields (Zostera sp.).
Biology. It spawns repeatedly from May to August. The females attach their eggs to the male ventral surface in front of the anal opening. The fecundity varies from 28 to 70 eggs. The straightnose pipefish is the only species of the family, which has a free larval stage due to preserved embryonal fins. Juveniles are found in the algae zone from June to early September . It feeds on plankton and fish fry [2, 9].
Similar species. Another six species of pipefishes are found along the Bulgarian Black Sea coast: Syngnathus abaster, S. acus, S. schmidti, S. typhle, S. tenuirostris and S. variegatus. The straightnose pipefish differs from them by the absence of a well-differentiated brood pouch and a reduced caudal fin.
Negative factors. The main threat to the species is water pollution.
Conservation measures taken. The species was listed in the Red Book of the Black Sea (1999).
Conservation measures needed. Protection of the lower reaches of the Black Sea rivers, the coastal lakes and the Black Sea coast against pollution.
References. 1. Drensky, 1951; 2. Stojanov et al., 1963; 3. Gheorghiev et al., 1960; 4. Gheorghiev, 1967; 5. Karapetkova, 1976; 6. Sivkov, 2000; 7. Sivkov, 2003; 8. Trichkova et al., 2006; 9. Svetovidov, 1964.
Authors: Yanaki Sivkov, Tihomir Stefanov, Teodora Trichkova