The Caspian Sea is located in an inland depression on the border of Europe and Asia1. It is the largest enclosed sea in the world, with a catchment area of 3. 5 million square kilometers, and is brackish, with salinity up to 13. 7 ‰1. The significant changes in water levels that occur combined with the presence of large shallow areas constitute a potential threat to biodiversity and to the many endemic species1. The rate of biological endemism in the Caspian Sea is extremely high and it has a large number of representatives from almost all major phyla on earth1.
The most important fauna of the Caspian Sea is the sturgeon, which constitute 85% of the standing stock of the world’s sturgeon population1. If there can be a single generalization about sturgeons, it is that they tend to be poky at life: their heart beats slowly; they respire slowly; they move deliberately, mature slowly, reproduce infrequently, and are slow to die4. These conservative life history traits have served sturgeons well over geological time scales4.
These fish species, which are living fossils, are now on the verge of extinction due to reduction of reproduction grounds, overfishing and water pollution by pesticides, heavy metals and oil products2. Poaching has dramatically increased during recent years and is thought to be among the main causes for the population decline of the sturgeon2. This paper discusses the urgent need to determine the ecological effects of overfishing sturgeons for caviar production including the steps taken for sturgeon conservation.
The current regulations being implemented for commercial caviar production and trade are also reviewed. Sturgeon Conservation 3 Sturgeons in the Caspian Sea Six species of sturgeon exist in the Caspian, belonging to the genera Huso and Acipenser1. During the early 20th century, the beluga (Huso huso), considered as the biggest sturgeon, accounted for approximately 40% of the sturgeon catch. Presently, the beluga accounts for less than 10% of the sturgeon catch1. The Russian sturgeon (Acipenser guldenstaedtii) accounts for between 40 and 50 % of the catch1.
The other species include: Persian sturgeon (Acipenser persicus); Sevryuga sturgeon (or starred sturgeon) is represented by the north Caspian (Acipenser stellatus stellatus) and the south Caspian (Acipenser stellatus stellatus natio cyrenis) forms1; Spiny sturgeon (or bastard sturgeon, or ship; Acipenser nudiventris); and Sterlet sturgeon (Acipenser ruthenus)1. North American Sturgeons Several of the 27 sturgeon species have a high commercial value on international markets, for caviar, meat, as well as sport fishing in North America3.
Populations are declining through increased poaching, illegal trade, habitat loss due to dam construction (preventing migration to spawning grounds), pollution, inefficient aquaculture and re-stocking techniques, lack of regional co-operation in conservation programs, and poor law enforcement3. As sturgeons are migratory fish that regularly cross international borders as part of their life cycle, international cooperation is a critical component of any plan to conserve them3. Sturgeon Conservation 4 Caviar Production and Possible Market Crisis
Caviar is made with unfertilized eggs from the female sturgeon, which can produce up to 15% of its body weight in eggs5. The fish is killed, the ovaries removed and the roe (ovaries containing mature eggs) is mixed with salt and canned for export to the lucrative international market, or for sale locally5. In the Caspian Sea, Russian anti-poaching officials and border guards have so far found more than 70 tons of sturgeon entangled in illegal nets, which is estimated to be only a small fraction of the illegal catch5.
Overfishing, for both legal and illegal markets, has continued to undermine the conservation prospects of the species and could herald the collapse of the stock and the international caviar market5. In theory the legal trade in caviar should act as an incentive to the governments around the Caspian Sea, but this trade is in severe risk of ending unless urgent action is taken to clamp down on the illegal trade5. Conservation
In the late 1990s, in response to international concern over the survival of sturgeon, both the Convention on the Conservation of Migratory Species of Wild Animals (CMS) and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) included sturgeon on their lists of concern3. Sturgeon Conservation 5 Recommendations While recognizing the complex nature of issues facing sturgeon conservation, the experts’ recommendations for future action include the following3: • Control poaching and illegal trade in caviar through:
• development and implementation of regional trade and law enforcement agreements; • improvement of social and economic conditions of people in the sturgeon range states; • improved enforcement of existing laws. • Improve efficiency in aquaculture, stock assessment and re-stocking through: • development of a unified method for stock assessment and monitoring; • Formulation of a “code of conduct” for each species that will increase the effectiveness of re-stocking programs. • Improve regional and international cooperation for sturgeon conservation through:
• regional agreements for sturgeon conservation and management particularly for the Amur River, the Black Sea, Azov Sea, and the Caspian Sea; • identification of potential protected areas in sturgeon Sturgeon Conservation 6 habitat; • national level action stimulated by NGOs, the United Nations Food and Agriculture Organization (FAO), conventions and other organizations; • funding support for sturgeon conservation from major financial and economic mechanisms such as the Global Environment Facility and World Bank as well as the private sector;
• increased public awareness of the threats facing sturgeon and opportunities for their conservation; • an information exchange network involving all parties involved in sturgeon conservation including FAO, Convention on Biological Diversity, Sturgeon Specialist Group, Convention on Migratory Species, and IUCN’s European Sustainable Use Specialist Group. Cited References 1. Mamaev, Vladimir. The Caspian Sea. European Environmental Agency. Europe’s biodiversity, biogeographical regions and seas. 2. [cited 2008 December 3]. Available from http://www.
caspianenvironment. org/newsite/Caspian-EnvironmentalIssues. htm 3. [cited 2008 December 3]. Available from http://www. ecoworld. com/Animals/articles/articles2. cfm? tid=262 4. Secor DH, Anders PJ, Winkle WV, Dixon DA. Can We Study Sturgeons to Extinction? What We Do and Don’t Know about the Conservation of North American Sturgeons. [cited 2008 December 3]. Available from http://www. cbl. umces. edu/~secor/sturgeon. html 5. [cited 2008 December 1]. Available from http://www. panda. org/about_wwf/what_we_do/species/news/index. cfm? uNewsID=2171