Freshwater fish species within the Natura 2000 National Network in Bulgaria: Achievements and Problems

Transcription

1 Freshwater fish species within the Natura 2000 National Network in Bulgaria: Achievements and Problems Lachezar Pehlivanov (1), Milen Vassilev (1), Apostolos Apostolou (1), Boris Velkov (1), Tihomir Stefanov (2), Stoyan Mihov (3) (1) Institute of Biodiversity and Ecosystem Research, BAS, (2) National Museum of Natural History, (3) WWF Bulgaria

2 231 NATURA 2000 Sites under the Habitat Directive (92/43/EC) are declared in Bulgaria covering about 33% of the country area. Three NATURA 2000 sites (Srebarna Lake, Upper Mesta River and Lower Mesta River are proposed also as sites of the LTER-Europe Network

3 Totally 26 species of the Bulgarian freshwater ichthyofauna are protected in the approved 142 sites of the Natura 2000 National Network Latin name/ English name Alosa immaculata/pontic shad Cottus gobio/bullhead Umbra krameri/mudminnow Aspius aspius/asp Barbus bergi/crimean barbel Barbus petenyi/balkan barbel Alburnus danubialis/danubian shemaya Alburnus schischkovi/rezovian shemaya Alburnus mandrensis/mandra shemaya Leucicus souffia/varion Pelecus cultratus/ziege Rhodeus amarus/bitterling Romanogobio kessleri/kessler s gudgeon Latin name/ English name Romanogobio uranoscopus/danubian longbarbel gudgeon Cobitis elongatoides/spined loach Cobitis strumicae/struma spined loach Cobitis pontica/struma spined loach Cobitis elongatа/danube loach Sabanejewia balcanica/golden spined loach Misgurnus fossilis/weatherfish Gymnocephalus baloni/danube ruffe Gymnocephalus schraetzer/stripped ruffe Zingel streber/danube streber Zingel zingel/zingel Eudontnmyzon mariae/ukrainian brook lamrey

4 Achievements: Habitat coverage The percentage of the identified potential habitats of different fish species covered by the proposed Natura 2000 National Network in relation to their total potential area all over the country varies from 15% to 83%. The habitats of 3 species only, may be considered as totally covered by the Natura 2000 National Network in Bulgaria: 1. Umbra krameri occurs only in the Srebarna Lake; 2. Misgurnus fossilis in wetlands adjacent to the Danube

5 Achievements: Habitat coverage 3. Leuciscus souffia occurs in one high mountain lake (Pirin Mountain - South West Bulgaria)

6 Achievements: Mapped distribution of priority species The Bitterling Rhodeus amarus is the species of the widest distribution represented in 109 Natura 2000 sites covering of about 53 % of its habitats. This species is absent only in the high mountain water bodies.

7 Achievements: Mapped distribution of priority species Barbus petenyi occurs in all rivers within the Danube drainage basin. Fifty one Natura 2000 sites cover of about 45 % of the potential habitats of this species protecting about 80% of its population in Bulgaria.

8 Achievements: Mapped distribution of priority species Barbus bergi occurs only in the rivers inflowing directly into the Black Sea. Although the proposed Natura 2000 sites cover only about 15% of the potential habitats of this species they protect about 85% of its national population.

9 Achievements: Mapped distribution of priority species The national population of Aspius aspius is distributed mainly in the Danube River and in the related water bodies but this species occurs also in several rivers of the Aegean Sea basin.

10 Achievements: Mapped distribution of priority species Special attention deserves the Bullhead Cottus gobio, probably the most endangered species in Bulgarian freshwater ichthyofauna. The potential habitats of this species are partially protected in the Natura 2000 sites Central Balkan buffer and West Stara Planina but significant habitats currently remains out of the Natura 2000 National Network.

11 Achievements: The highest species richness occurs in the sites covering zones of the Danube River. Some additional protected areas were proposed to extend the initially declared sites and currently they can be considered more or less sufficient for adequate protection of the habitats of 10 resident and 1 diadromous fish species enlisted in the Directive 92/43/EC: Alburnus danubialis, Aspius aspius, Romanogobio vladykovi, Pelecus cultratus, Cobitis elongata, Gymnocephalus baloni, Gymnocephalus schraetzer, Eudontomyzon mariae, Zingel zingel, Zingel streber, Alosa immaculata. TTTTTTT

12 Problems: Species identification Some fish species enlisted in the Annex 2 of the Habitat Directive what is a prerequisite for difficulties in conservation activities. That s why 8 fish species of the Bulgarian ichthyofauna of conservation value have not their own status in the Natura 2000 documents but are considered equivalent of the above mentioned species: Barbus petenyi = Barbus meridionalis Sabanejewia balcanica = Sabanejewia aurata Cobitis elongatoides, Cobitis strumicae & Cobitis pontica = Cobitis taenia Alburnus danubialis, Alburnus schischkovi & Alburnus mandrensis = Chalcalburnus chalcoides

13 Problems: Management of the river basins & water bodies Morphological changes and water pollution are identified as the main threats to the most part of fish species

14 Problems: Invasive species The competition of non-native fish species as well as change the environment by some invertebrates (such as Dreissena spp.) must be also pointed as threats for the native fish communities

15 Problems: Sustainable using vs. overfishing & poaching: Some species, such as: Alosa immaculata, Aspius aspius, Barbus bergi, Barbus petenyi and Zingel zingel, are identified potentially threatened by overfishing and poaching

16 Therefore the protection of habitats is of primary importance for the conservation of target fish species.