European Mud-minnow
Umbra krameri Walbaum, 1792
Order Esociformes
Family Umbridae
Conservation status: in Bulgaria: Critically endangered CR [B1a, c]; International: IUCN [VU A1ace], BeC-II.
General distribution. The middle and lower reaches of the rivers Danube and Dniester, and some of the adjacent lakes. It was introduced to some European countries, such as: Great Britain, Germany and Poland.
Distribution and abundance in Bulgaria. In the past, the species was found in most marshes along the Danube River [1]. Then, for a long time (over 80 years), it had not been recorded, and therefore, it was not included in the comprehensive works on the ichthyofauna of Bulgaria [2, 3]. In 2004, the species was found again in Srebarna Lake, in the canal connecting the lake with the Danube River [4]. There are no data about the state of the Bulgarian population.
Habitats. It is found only in permanent fresh water marshes and flooded areas of rivers overgrown with dense macrophytic vegetation.
Biology. The species reaches sexual maturity at the age of 2 years. It spawns in the period between March and April, building peculiar nests that are guarded by the females. The fecundity of the females ranges from 1 500 to 3 000 eggs. It feeds on zooplankton and insect larvae. The life span is about 7 years [5].
Similar species. In Bulgaria, none.
Negative factors. Loss (degradation) of habitats, as a result of draining of marshlands; water pollution.
Conservation measures taken. The only habitat of the species in Bulgaria is included in the Srebarna Biosphere Reserve.
Conservation measures needed. Preparation of an Action Plan for the protection of the species in Bulgaria and development of a programme for the reintroduction of the species into Srebarna Lake.
References. 1. Kovatcheff, 1923; 2. Drensky, 1951; 3. Karapetkova, Zivkov, 1995; 4. Velkov et al., 2004; 5. Froese, Pauly, 2006.
Authors: Tihomir Stefanov, Teodora Trichkova
