Historical review and new initiatives for sturgeon
fisheries, aquaculture and caviar production in Serbia and Montenegro
Nikcevic1, M., Lenhardt2, M., Cakic2, P., Mickovic1, B., Kolarevic1, J. and Jaric1, I.
1Centre
for Multidisciplinary Study, University of Belgrade, Kneza Viseslava 1, 11000
Belgrade, Serbia and Montenegro,
2Institute
for Biological Research, 29 novembra 142, 11000 Belgrade, Serbia and Montenegro
The Acipenseriformes include only 27 species in
comparison to 20,000 existing teleost species. For biologists, acipenseriforms
are interesting as a group which exists for more
than 250 million years having survived the cataclysmic events that extinguished
many other forms of lives; for the public, they are prize exhibits in aquaria
and, of course, the source of much prized caviar (Bemis and Findies 1994).
Seven species of all existing Acipenseriformes were recorded in waters of
Serbia and Montenegro (Jankovic and Krpo-Cetkovic 1995): beluga (Huso huso
Linnaeus, 1758), Russian sturgeon (Acipenser gueldensatedtii Brandt,
1833), ship sturgeon (Acipenser nudiventris Lovetzky, 1828), stellate
sturgeon (Acipenser stellatus Pallas, 1771), European Atlantic sturgeon
(Acipenser sturio Linnaeus, 1758), Adriatic sturgeon (Acipenser
nacarii Bonaparte, 1836) and sterlet (Acipenser ruthenus Linnaeus,
1758). Today, Acipenser sturio is one of the most threatened freshwater
fish species worldwide (Arne and Williot 2002) while Acipenser nudiventris
is very rare in the Danube River Basin and can be found
only occasionally in the catches (Hensel and Holcik 1997). Ŕll other species
are listed on Appendix II of the Convention on International Trade in
Endangered Species of Wild Flora and Fauna (CITES).
Since 1997 all sturgeon species have been listed on CITES. They are also listed on the Natura 2000 list, on Appendix II of the Convention on the Conservation of Migratory Species of Wild Animals (CMS, or Bonn Convention) and some species are listed on Appendices II or III of the Convention on the Conservation of European Wildlife and Natural Habitats (Bern Convention).
Despite of all these
measures, illegal and poorly regulated legal harvesting of these species for their
much-prized caviar still goes on and populations are continuing to decline. The
major cause for this is the absence of multilateral fisheries management for
shared stocks and unsustainable fishing efforts.
Solving of this problem should be one of priorities
for countries in transition, concerning the high value sturgeon resources have
for their socio-economic features.
At the end it should be noticed that the Danube River
is the only reverie system in Europe, which still bears a reasonable chance of
preserving sturgeon biodiversity.
The Acipenseriformes live almost exclusively in the
Northern Hemisphere inhabiting temperature waters above 30th
parallel in northern Europe, Asia and North America. Half of the extant number
of species occurs in Europe, mostly in the Ponto-Caspian region (Billard and
Lecointre 2001). Biogeographic analysis suggests that Acipenseriformes
originated in Europe and that early diversification took place in Asia (Bemis
and Kynard 1997).
Impact of Iron
Gate I and II construction on sturgeon populations in Serbian part of the River
Danube
Construction of Iron Gate I and Iron Gate II in 1970 (943 km) and in 1984 (863 km) on the Danube
River prevented sturgeons in reaching their historical place of spawning and
significantly decreased catch of sturgeon in Serbian part of the river. Today,
migratory sturgeon species (beluga, Russian sturgeon, stellate sturgeon) can be
caught only in 17.8 km stretch of the Danube River.
The beginning of Iron Gate I construction prevented migration of
anadromous species and at first induced increase in catch during 1965-66. At
the time Iron Gate I was finished, stellate sturgeon was very rarely caught and
the same thing happened with Russian sturgeon after completion of Iron Gate II.
Due to very low catch of these two sturgeon species in the Serbian part of the
Danube River, they were protected in 1995 with the Act on the
protection of natural rarities (SGRS No 50/93). This act is one of the most
important legal acts issued in the Republic of Serbia, which deals with
protection of Acipenser sturio, Acipenser gueldenstaedtii
and Acipenser stellatus (Sekulic 1999). The effects of dams building
were also expressed on catch of beluga but with certain time delay in comparison
with stellate and Russian sturgeon, which is probably in correlation with
longevity of life span for these species.
Sturgeon catch
Inhabitants of the Greek colonies in the area noted the catch of
sturgeon in the Lower Danube River in 5th and 6th century B.C. By the beginning
of the 16th century sturgeon catch decreased in the Middle Danube
River and in the 18th century fishing of migratory sturgeons in the
Austrian Stretch of the Danube River was abandoned. From 19th
century over fishing and river modification become main reasons for decrease in
sturgeon population, with water pollution becoming one of the most important
factors in 20th century. Statistical data of catch of anadromous
sturgeon species in Serbian part of the Danube River in period from 1960-1997
showed that the maximum value for catch of stellate sturgeon was in 1965 (8605
kg), Russian sturgeon in 1975 (17 588 kg) and for beluga in 1975 (20 710 kg).
Nowadays due to very rare catch of stellate and Russian sturgeon these species
are protected, while the official data about beluga catch are not reliable due
to existing strong black market in last 5 years.
Caviar
The first written record of caviar was made by Batu Khan (grandson of
Ghengis Khan) in 1240’s. Caviar industry started in Eurasia and in
Mediterranean. At the beginning sturgeon roe was heavily salted and packed in
wooden casks. Possibility for longer caviar preservation on ice helped the
further development and expansion of caviar trade and industry. The whole caviar craze began in the mid 19th
century.
Most of the populations of sturgeons all
over their areal were crashing around the time of World War I. World War I and
II gave sturgeons a break.
In 1950s and 1960s building of series of dams on rivers resulted in cutting off sturgeons spawning grounds.
To solve this problem Russians started building hatcheries for sturgeon
artificial spawning. After former USSR fell apart in 1991 lots of hatcheries
were forced to close down together with lots of other factories due to very bad
economic situation in successor countries. Similar scenario happened in former
Yugoslavia as well.
Fishing
Company Kladovo
In the period from 1947-2000 Fishing Company Kladovo was the User of
the Fisheries District in lower part of the Danube River in Serbia, where catch
of anadromous sturgeon was performed. In that period well-known Kladovo
sturgeon caviar was produced but there are no data about annual production of
caviar in that period. Nowadays, CITES quota for export of caviar from Serbia
and Montenegro is 850 kg for 2002 and 2003 (www.cites.org/common/quotas).
Sturgeon aquaculture in Serbia made its first step with construction of
state hatchery facilities as compensation for shortening of sturgeon migration
way by construction of Iron Gate I. The hatchery started to work in 1990 with
successful sturgeon artificial spawning in period from 1990 to 1996, but with
unsolved problem concerning transfer of larvae from endogenous to exogenous
feeding. Due to unfavorable socio-economic conditions in Yugoslavia at the end
of past century the Fishing Company “Mala Vrbica” collapsed.
At the beginning of 2000 they were no longer in charge of Danube waters
downstream Iron Gate II and they had no money for purchasing the fish from
local fishermen.
Political and
economic changes in lower Danube region
Last decade of XX century was a very stormy period, both politically
and economically, for countries in the lower Danube region. This transition,
which still goes on, affected all segments of society. Among other things
strict fishing controls seized to exist, which led to the excessive, clearly
unsustainable, fishing, pressure on lot of Danube fish species.
Major factor driving unsustainable legal and illegal sturgeon fisheries
in this region can be assigned to the fact that beluga caviar is one of the
most prized fish product worldwide.
Having in mind that the Danube River is International River, there is
an urgent need for establishment of inter-state agreement and co-operation in
conservation management, stock assessment and monitoring, quotas and their
allocation, fishing effort control, and surveillance or statistical sampling of
commercial catches.
Complex
anthropogenic impact on sturgeon population
Russian scientist analyzed sturgeon eggs in Caspian Sea population and
found that every single egg had some kind of deformity, which were probably the
results of existing water pollution. This
situation can have serious repercussion on sturgeon reproduction and
development. It can make mature specimens less fertile and it can also lower
fingerlings survival rate.
Pollution together with dam building and historical harvesting of
sturgeon species makes complex of anthropogenic impact on sturgeon population.
State of
sturgeon scientific investigation
The most significant research on the biology and
cultivation of sturgeon from the Ponto-Caspian region was conducted in the
former Soviet Union. Until the second half of the 20th century
Soviet scientists had a monopoly on sturgeon studies. After 1950, Western
Europe, America and Far-East programs for restocking local population of
sturgeon were initiated. In spite of the fact that many of European scientists
are involved in sturgeon research, no effort was done for better exchange and
dissemination of the information and experience between scientists from Western
Europe countries where aquaculture of sturgeon is well developed and scientists
from countries in the Lower Danube Region where aquaculture of sturgeon at the
beginning, but still has existing natural sturgeon population.
Investigation concerning sturgeon in Serbian part of the Danube River
was conducted mainly by Jankovic (1958, 1993) and Ristic (1963).
Perspectives
for aquaculture development and restocking
While aquaculture of sturgeon is well developed in Western European
countries, it is at its beginning in the lower Danube region countries,
including Serbia and Montenegro. The development of sturgeon aquaculture in
this region could be useful as well as for possible restocking as for
diminishing pressure on natural population. Connected with restocking programs
a need for genetic variability analysis of sturgeon stock is also expressed.
Social and
economic policy issues relevant to sturgeon fisheries and aquaculture
The main sturgeon related problems in Serbia and Montenegro today are
connected with need for better integration of knowledge and skills from
different disciplines. Together they should create relevant basis for sturgeon
aquaculture development that integrates social, economical and environmental
parameters.
The urgent need exist for improving communication among scientists,
fisheries and wildlife managers due to implementation of an adaptive management
approach as an interim measure until full scientific assessment on sturgeon
stocks is available.
References
Arne, L. and Williot, P. 2002. Genetic aspects of conservation of the common sturgeon Acipenser sturio. Annual Meeting, Society for Conservation Biology.
Bemis, W.E. and Findeis, E.K. 1994. The sturgeons’ plight. Nature 370, 602.
Bemis, W.E. and Kynard, B.
(1997). Sturgeon rivers: an introduction to Acipenseriform biogeography and
life history. Environmental Biology of Fishes 48, 167-183.
Billard, R. and Lecointre, G. 2001. Biology and conservation of the sturgeon and paddlefish. Reviews in Fish Biology and Fisheries 10, 355-392.
Hensel, K. and Holcik, J. 1997. Past and current status of sturgeons in the upper and middle Danube River. Environmental Biology of Fishes 48, 185-200.
Jankovic, D. 1958. Ecology of Danube sterlet (Acipenser ruthenus L.). Institute for Biological Research, Belgrade, 145 pp.
Jankovic, D. 1993. Populations of Acipenseridae prior and after the construction of the HEPS Djerdap I and II. Ichthyologia 25(1), 29-34.
Jankovic, D. and Krpo-Cetkovic, J. 1995. Diverzitet slatkovodnih riba (Osteichthyes) i kolousta (Cephalaspidomorpha) Jugoslavije sa pregledom vrsta od medjunarodnog znacaja. Biodiverzitet Jugoslavije sa pregledom vrsta od medjunaradnog znacaja, 425-445. Ekolibri, Bioloski fakultet, Beograd.
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