Stocking inland

waters of the

Islamic Republic

of Iran

Devin M. Bartley1 and K. Rana2
1Fishery Resources Officer
Fishery Resources Division
2Fishery Statistician (Aquaculture)
Data and Statistics Unit



In 1992, the Government of the Islamic Republic of Iran's (IRI) policy for the fisheries, livestock and poultry sectors was aimed at increasing production to meet domestic needs. Today there is also a policy to increase non-oil exports from IRI, as well as a desire to improve the nutritional food security of Iranians through increased consumption of fish. Shilat, the government agency in charge of fisheries and aquaculture, aims to increase per capita fish consumption from the current level of approximately 5kg/yr to 13.5 kg/yr and to increase aquaculture production from approximately 60,000 mt/yr presently to 102,000 mt/yr over the next five years through both direct and indirect assistance. Large restocking programmes for several species of fish in the Caspian Sea and smaller inland water bodies are actively supported by Shilat and play a major role in many fisheries. The purpose of this article is to highlight some of the issues surrounding the stock enhancement practices primarily of the Caspian Sea in IRI.

Although inland fishery production has increased over the long term (Figure 1), an unknown proportion of the increase has been due to large-scale restocking efforts and many of the fisheries may be severely threatened. The fisheries of the Caspian Sea are being heavily impacted by environmental degradation and illegal fishing activities. Extensive oil exploration and extraction are increasing throughout the region. In the past, the Soviet Union was a major regulator of the fisheries in the northern sections of the Caspian Sea. Now however, this regulatory force no longer exists and there are extensive poaching and illegal fishing activities. Many of the Caspian Sea's anadromous fishes, such as sturgeon, Caspian trout, Salmo trutta caspius, and mahi sephid, Rutilus friisi kutum, can no longer access inland spawning grounds because of riverine water diversion and dam development, and the fisheries are now heavily dependent on stocking.

Sturgeon produce the most valuable fishery product from the Caspian Sea _ caviar, estimated to be worth approximately $US 45 million in IRI, but these fishes are very susceptible to overfishing and environmental degradation. In Asia and the former USSR, sturgeon fisheries have drastically declined and illegal harvest has presumably increased substantially. This decline has been seen elsewhere in the world and as a result, all sturgeons are now listed on Appendix II of the Convention on International Trade in Endangered Species (CITES).

In the last issue of FAN we reported that Drs D. Bartley and K. Rana travelled to the Islamic Republic of Iran on a mission to help Shilat evaluate stocking programmes and the management of aquatic genetic resources in aquaculture. This article reports on some of their findings concerning stocking; findings on aquaculture will be presented in a future issue of FAN.


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Stocking programmes - status

Stocking the Caspian Sea with sturgeon started in Russia in the 1950's and in Iran in the 1970's. Although many of the former Soviet Union hatcheries are no longer producing fingerlings for stocking, in IRI fingerling production for restocking of sturgeon, mahi sephid, and Caspian trout, pike-perch, and bream has increased from around 15 to 196 million from 1978 to 1996; the mahi sephid accounts for the majority of the production (Table 1).

Table 1. 1996 fingerling production from Shilat hatcheries for restocking the Caspian Sea and other inland water bodies. (N = number of fingerlings stocked (millions)).


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There is evidence that the harvest of these enhanced or culture-based fisheries is correlated with stocking intensity and that stocking has, in fact, maintained these fisheries (Abdoulhai, personal communication). The mahi sephid fishery, which collapsed in 1980, has risen from 500 tonnes in 1981 to around 10,000 tonnes in 1996 following restocking from around 400,000 fingerlings/yr in 1981 to around 142 million/yr in 1997 (Figure 2).

Shilat is examining the stocking programmes as part of a national programme to increase fish production and conserve valuable aquatic diversity. Other approaches are also being used to manage the sturgeon fisheries in addition to the large scale sturgeon restocking programme. For example, the government has bought back fixed gill nets from 4,000 fisherfolk and trained them to use beach seines at a cost of approximately US$ 10 million. This was deemed necessary because, in addition to the targeted species, these nets also inadvertently trapped juvenile sturgeon and Caspian trout. There is a newly created Sturgeon International Research Institute that has, or is developing, programmes on genetics, nutrition, water quality, physiology, and fish health.


The potential to optimise fishery rehabilitation strategies is substantial in IRI based on the following:

• Well developed hatchery facilities for artificial reproduction and larval rearing in several areas along the Caspian Sea shore (Figure 3);

• Increasing capacity in aquaculture related sciences, such as genetics, physiolology, biotechnology, etc (Figure 4).

• Extremely high value of certain fishery products, (caviar);

• Interest from the international community in rehabilitating Caspian Sea fisheries;

• Commitment of Shilat to restore fisheries of the Caspian Sea (Figures 5-7).

Similarly, for pike-perch and bream, landings increased from around 5-10 tonnes in 1990 to around 35-40 tonnes in 1996. However, the stocking program-me in IRI is expensive; the cost of running the Shilat hatcheries was reported to be one billion tuman (3.3 million US$, 300 tuman = 1 US$). In addition, little information exists on the biology and ecology of many of the stocked species; levels of natural spawning/reproduction are unknown and difficult to determine because hatchery releases are not tagged.

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Figure 2. Mahi sephid broodstock traps and egg incubators. Broodstock are collected and spawned at riverside. Approximately 90% of migrating adults are intercepted. Photo courtesy of Shilat.


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Figure 3. Shaheed Beheshti Fish Propagation and Rearing Complex produces sturgeon and bony fish fingerlings for stocking. In 1997, 9 million 3-5 g sturgeon were produced here. 50-60% of facility is devoted to production of live food for larvae and fingerlings.

The IRI has overcome many constraints to aquaculture and fishery development, but problems persist with rehabilitation of Caspian Sea fisheries. These include:

• Long generation time of key species, such as sturgeon;

• Lack of general awareness of, and extension services for genetic technologies in some areas;

• Extensive activities that immediately threaten the fisheries, e.g. oil extraction, illegal fishing, habitat degradation;

• Lack of regional/international coordination and commitment to the problem;

• Poor information base on stock structure, stock biomass, migration routes, and genetic stock structure of key species; and

• Lack of accurate assessment of alternatives to restocking.

The mission of Drs Bartley and Rana identified some broad activities that could assist in the rehabilitation and conservation of Caspian Sea fisheries:

Measures to ensure the immediate safety of the resource through ex situ conservation are urgently required in light of the numerous threats facing several of these fisheries, e.g. oil pollution, illegal fishing, and habitat loss, and the difficulty in addressing them in a timely fashion for in situ conservation. Ex situ measures such as gene banks of both live fish and frozen semen can be developed in IRI in conjunction with on-going activities at the International Sturgeon Research Institute and in the Kelardahst region.

• Efforts should be made to evaluate more rigorously the benefits of the stocking programme; stocking strategies need to be optimised and put into a broader fishery management context that includes habitat protection/rehabilitation, education and outreach, fishery management, and enforcement.

• International workshop on stock rehabilitation in the Caspian Sea should be convened to bring all stakeholder in the region together. Management of sturgeon and other stocks is being hampered by lack of regional coordination and by insufficient data on the population genetic structure and size of the stocks. The extent of the migration routes of many species is not known, therefore it is difficult to determine whether the products of Iranian enhancement are harvested by other littoral States. The States bordering the Caspian Sea are beginning to claim control of their EEZ and this may affect many of the migratory fish stocks that are shared by more than one country.

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Figure 4. The capacity of Iranian fishery scientists has improved due to participation in advanced training both in Iran and abroad. Drs Bartley and Rana provided a one day training course on genetic resource management in stocking programmes, aquaculture, and ex situ conservation.

Concluding remarks

The release of hatchery-raised fish to maintain or increase fishery production is controversial; if done incorrectly, stocking programmes can endanger wild resources and be a financial drain on the public institutions that support the hatchery. Others feel that stocking is a good means to provide fish in habitats that are affected by development and to increase production from managed water bodies, e.g. reservoirs.


Evidence in the Caspian Sea suggests that stocking has maintained several important fisheries for a number of years. However, the future of these fisheries is uncertain and the IRI is to be commended for its efforts to examine critically the role of hatcheries in fishery enhancement and conservation.

We would like to gratefully acknowledge the assistance of Shilat and especially Mr Maygolynedjad, Mr Abdoulhai, Mr Yousefpor, and Mr Pourkazemi.

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                         Figure 5. The ships sturgeon, A. nudiventris, like many sturgeon, has declined in Iranian waters  and efforts to restock and to create genebanks (live and frozen) are underway.


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Figure 6. Caspian trout broodstock, collected from Tonekobon River for restocking the Caspian Sea. Two males are used to fertilize eggs from 2 females. Due to cold water temperature fish reach only 10 g in 10 months.

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Figure 7. Dr Krishen Rana examining sturgeon fry at Shaheed Beheshti Fish Propagation and Rearing Complex. Larvae begin feeding at about 4 d on live food such as Artemia, daphnia, and oligochaetes. At 60-80 mg, larvae are transferred to earthen ponds and stocked into major rivers at 2-5 g.