Lake Fertő Fish Fauna and Fisheries present situation and future perspectives

1. Lake Fertő Fish Fauna and Fisheries present situation and future perspectives László Stündl and Zoltán Karácsonyi University of Debrecen 8th LAKEPROMO Seminar and Meeting, Budapest, 10-14 October 2007

2. Introduction • Main features of the lake: • 5th largest lake in Europe • Shallow lake (avg. depth < 1m) • Total salt cont. > 2000 mg/l, pH >8.0 • Small watershed: 1200 km2, lake: 310 km2 (ratio 3:1 !) • Water regime strongly depending on precipitation (2 smaller rivers, Hanság drainage channel) • 1/4 thof the Lake (75 km2) is in Hungary • 15% open water, ~1% „locked” lakes 84% reed 8th LAKEPROMO Seminar and Meeting, Budapest, 10-14 October 2007

3. Fisheries 1. • Features of the fish fauna: • Fisheries data from the 16th Century (!) • Fauna: 23-24 species • 30 endemic and 2 adventive species in the 50’s and 60’s (eel - Anguilla anguilla & Black bullhead -Ictalurus melas) • Stocking with Eel, Pike-perch, Pike, Common carp, European catfish from 1975 • Overstocking with Eel (4 million fingerlings/year) in the long-run (15-20 years) had negative effect 8th LAKEPROMO Seminar and Meeting, Budapest, 10-14 October 2007

4. Fisheries2. • Present practice: • Fishing right: Nat’l Park & Water Authority • Recent fauna: only 17 endemic and 6 adventive species • Fisheries: 9 professional small-scale fisher-man (of which 7 locals): 2500 fyke nets, 3500 m gill nets, 300 m trammel nets, 3 seines. Electric fishing machine has been banned for several years • Overfishing in the Hungarian side 8th LAKEPROMO Seminar and Meeting, Budapest, 10-14 October 2007

5. Faunistic data: Source: 1) Heckel és Kner 1858, 2) Herman 1887, 3) Vutskits 1918, 4) Seligo 1926, 5) Mika és Breuer 1928, 6) Varga és Mika 1937, 7) Sauerzopf és Hofbauer 1959, 8) Kritscher 1973, 9) Faludi 1974, 10) Hacker és Meisriemler 1978, 11) Hacker 1979, 12) Keresztessy 1991, 13) Herzig 1994. Legend: * Present species, + Extinct species 8th LAKEPROMO Seminar and Meeting, Budapest, 10-14 October 2007

6. Commercial fisheries landings Average yields (kg/ha) Fishing ground: 1744 ha 8th LAKEPROMO Seminar and Meeting, Budapest, 10-14 October 2007

7. Anglers’ catches 8th LAKEPROMO Seminar and Meeting, Budapest, 10-14 October 2007

8. Continuous monitoring from 2003 Sampling sites 8th LAKEPROMO Seminar and Meeting, Budapest, 10-14 October 2007

9. Recent fauna of Lake Fertő 8th LAKEPROMO Seminar and Meeting, Budapest, 10-14 October 2007

10. Evaluation of the fish fauna • The recent fish stock is not adequate regarding both quantity (biomass) and composition • Decreasing stock of commercial species, younger groups are missing (no spawning) • Stabile and dominant species (bleak, bream, zope) Reasons & solutions • Limited natural spawning (due to water level) • No reproduction and significant fishing pressure • Stocking is not sustainable! (2+ 3+ C.carp, predator fingerlings) • Solution: spawning ground development and their canalisation to drive back the juveniles into the lake • Financing: EU funds 8th LAKEPROMO Seminar and Meeting, Budapest, 10-14 October 2007