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SECTION 2. THE BIOLOGICAL ENVIRONMENT 2.1. Species 2.2.1 Zoogeographical Realms The modern Caspian was originated as part of an ancient, brackish pontic lake-sea since 5-7 million years ago. Thus, the oldest living organisms in this region are among the group of autochthonous, brackish water organisms. Among this group, there is a high percentage of endemic species and even genera. The rest of modern assemblage of organisms in the Caspian is derived from the following three major origins:
The zoogeography of land animals and plants are discussed in relevant chapters. 2.2.2. Plants and Animals A. Forests Nature of Iranian Forests The Iranian forests belong to the European-Siberian growth region in the Holoarctic. This region includes parts of Europe and Northern Asia. The climate varies from cold to moderately warm weather. From the flora perspective, this region could be divided into the sub-regions of Northern, Atlantic, Central Europe and Pontic. The Pontic sub-region in the Middle East are represented by Accino-Hircnai Province. This sub-region includes northern Turkey’s mountains, the northern slopes of the Alborz mountains and the coastal areas in its vicinity. This is well adapted for the growth and expansion of forests and its annual rainfall is more than 1,000 mm. A part of this region enjoys summer rainfall as well. The flora of this region consists of 40% European-Siberian species, 22% Mediterranean-European-Siberian and 8% Iranian-Turanian. One of the most notable features of this region is its suitable environment for those groups of flora that were in danger in Europe at the expansion phase of cold weather in the later years of the Third Period (Newgeon Period). This grouping of flora expanded rapidly in this region and became part of the endemic species. There are other sub-provinces called the Hyrcanica that has less richness, but still enjoys a variety of tree species. It is divided into three groups. One of these groups is the Alnetea Hyrcanica, which includes various species like the forests of the Caspian coastal area. Iranian forests can be categorized ecologically as consisting of the following biomes:
Caspian Forests These forests belong to the broadleaf deciduous biome, which is widely distributed from North America to Europe and Asia. These forests receive considerable precipitation, between 750 – 2,200 mm. Temperatures are moderate but there are four well-distinguished seasons. Temperatures during the winter often drop to below 0° C making the winter months the season one of vegetation dormancy for trees. The average annual maximum temperature during the warmest months ranges from 28° -34° C and the average annual minimum temperature during the coldest month ranges from 1° -2° C. The absolute minimum temperatures are between 1° -10° C. There are close similarities in the physionomic and taxonomic aspects between Caspian forests and European and American deciduous forests. The following genera are common between North American, European and Caspian Forests: Beech (Fagus) Maple (Acer) However, North America has some exclusive genera such as Hickory (Carya), Tulip tree (Liriodendron), Sweetgum (Liquidambar), Witch hazel (Hammamelis), etc. There is more similarity between European and Caspian forests. Many species are common, especially the Herbaceous species. The following species are common to both Caspian and European forests: Acer cappadocicum Cerasus avium The following species are found exclusively in Caspian or Hyrcanian forests: Parrotia persica Fagus orientalis The Caspian forests have a high moisture content, so forest trees are host to many epiphytes such as mosses, ferns, lichens, mistletoes and some flowering plants. Soils are productive and rich in minerals and organic matter. There are many well-known communities in these forests, the most important ones being:
The last three communities cover the top of high mountains or the zone between the timberline and sub-alpine grasslands. There are some relics of Betula pendula forests on the high mountains of Taleqan, Shahrestanak and Semnan of the Alborz range. Stratification in forest structures is well developed. The main commercial trees, Fagus orientalis or Caspian beech make a canopy as high as 40 m. Subdominant, medium and shrub strata also exist if there is adequate light which penetrates from the canopy. When the canopy is tightly closed and there is no more than 1%-2% of light, there will be no herbaceous strata. With a light intensity of more than 2%, some characteristic species of beech forests can be found on rich moist soils, such as: Epimedium pinnatum Euphorbia amygdaloides These species are the same as those in European forests. With increasing light intensity, especially when it is more than 10% -15%, other species of “light-seekers” can be found. In beech forests, some important commercial trees are present in very low density. These include Ulmus glabra, Acer velutinum and Acer cappadocicum. They are not, however, climax communities. The Caspian forest areas are among the most unique and splendid biomes of the world. Serious efforts should be made to save these areas from devastation, a danger that intensifies year by year. Over-exploitation is an increasingly serious threat to this biome. According to an estimate made by the Forest and Range Lands Organization, the total area of the Caspian forest in 1963 was 3,420,487 ha . In 1980, a new inventory was made which estimated the total forest area at 1,900,000 ha. During the last 13 years, there has been a continuing degradation of forest area, so much so that today the total area of the Caspian forest is approximately 1,800,000 hectares. If the areas that receive more than 500 mm of precipitation were considered forests, the total area would be about 3,600,000 ha. In addition to dimensional degradation, the forest’s standing crop or biomass is also being destroyed. Before destructive exploitation, the average biomass of the Caspian forest was about 300 tons per ha. Today the average is less than100 tons per ha. In altitudes lower than 600 meters, the areas have been almost completely cleared of valuable timber. The situation is similar in high altitudes where the inhabitants of sub-alpine pastoral areas have devastated the sub-alpine forests by selective removal and later by complete removal of vegetation. Forest Distribution and Specifications Golestan Province: The entirety of the southern and southwestern areas as well as parts of the eastern regions of the Gorgan plain is covered with forest, totaling an area of 421,373 ha in 1998. There are three forest parks totaling 1,224 ha and there is 2,930 ha of artificial forests. The total production from these forests is estimated at 269,022 cubic meters. Mazandaran Province: The total area of the forest in this province is estimated at 965,000 ha which is mainly comprised of broad leaf trees. The forests in the east of the province are connected to the Minoodasht and Golestan forests and are distributed at two major regions, Sari (645,000 ha) and Nowshahr (320,000 ha). From these forests, 487,195 ha are used commercially, 184,000 ha are protected and the rest are regarded as forest lands or over-used forests. There are 11 forest parks totaling an area of 5,494 ha and 29,877 ha of artificial forests. The total of the forest woods used in this province is estimated at 770,551 cubic meters. Gilan province: There were 567,524 ha of forests in Gilan province in 1998 out of which, the Astara area with about 80,000 ha ranks first in the region. These forests are graded 1-2-3 with an area of 107,894; 182,758 and 211,972 ha respectively. The area of artificial forests in 1998 was estimated at 1,062 ha, there are also 16 forest parks totaling 5,394 ha, and 5 forest biospheres totaling 2,373 ha. The commercial and non-commercial utilization is 310,375 cubic meters (184,202 cubic meters for commercial and 126,173 cubic meters for non-commercial use). Importance and Condition of Iran’s Commercial Forests Now only 1.3 million hectares of forests in the Caspian Sea region are commercially exploited. The remaining areas have been nearly much degenerated, destroyed or have been designated as protected areas. According to climatic and ecological conditions, the potential annual growth is estimated to be about seven cubic meters per ha (Dorostkar, 1988), or a total of approximately nine million cubic meters per year [1.3 million * 7 = 9.1 million] . However, given the socioeconomic condition of the local population, at present, there is an actual maximum annual growth of only three cubic meters, translating into a harvest of about four million cubic meters per year [1.3 million * 3 = 3.9]. According to studies carried out in 1987 in the Hyrcanian forests in northern Iran extending from Astara in the west to Golidaghi at the northeast end, there are 103 watershed areas (98 primary and five secondary areas). The total forested land in the watershed areas is 1,900,000 ha. Of this, 77,842 ha are shrub land in need of afforestation. The general situation of the forest areas can be described as follows:
In terms of slope, approximately 544,529 ha of forest areas have a slope of less than 15° and 882,584 ha have slopes between 15° -30° . About 124,989 ha have slopes between 30° -50° and 7,636 ha have slopes of over 50° . The minimum altitude in forest areas is 20 meters (in basin areas 2 and 4) and the maximum is 3,808 meters (in basin area 40 A). The existing area of commercially usable forest stand is estimated at 260 million cubic meters. Because commercial forests are limited, the per capita commercially usable forest in 1991-1992, with respect to a population of about 60 million, was 0.02%. Thus, the commercial northern forests of the country are extremely important in providing the raw materials for the wood industry and the wood and lumber needed for workshops nationwide. The important species of trees on commercially usable forests are: Beech Fagus orientalis Forest Users According to statistics from 1987, in the northern forest regions, there are 4,316 populated areas, of which, 60% has one to 20 families and the rest over 20 resident families. 3,401 of these population areas are located inside the forests and the rest on the outskirts of the forest areas. The total population inside the forests is 464,562. The total number of families in permanent dwellings in 1987 was 165,071 and their total population was 1,061,391. In the entire northern watershed areas, there are 33,107 livestock units with 4,370,516 head of livestock. In terms of herding methods, the ratios are as follows:
Regarding the number of animals, 78.4% of the herding units had less than 200 head of sheep and goats or 40 head of cattle. The remainder of the units had greater numbers of livestock. In addition to these animals, there are 1,427,030 livestock units for domestic (katool) animals in the watershed area dwellings. The work force of the livestock units is 50,054 people, of whom, 32,258 breed animals and 17,796 are shepherds. About 40% of the breeders are above 50 years of age, while 48% of the shepherds are between 10-18 years old. The annual consumption level of fuel wood by animal husbandry units totals 2,875,815 cubic meters and 84,690 cubic meters of wood were cut for use in stables. The total number of animal husbandry camping groups inside forest areas is 28,521 and 57,042 ha of forests have been cleared to make room for these places. The major destruction inflicted on forests in the north region includes:
B. Rangelands Area and Classification of Rangelands According to available data and estimates, the area of Iranian rangelands is 90m ha which is approximately 55% of the total land area of the country. The national rangeland’s can be divided into the following three vegetation groupings (Figure ?). Grass ranges with good to average condition cover 14m ha. These are primarily located in mountainous regions and climatically good areas. Shrub-land ranges with weak to average conditions cover an area of 60m ha and are found mostly in semi-steppe regions with rainfall of less than 200 mm. Desert ranges covering an area of 16m ha are found in areas with rainfall of less than 100 mm. Table ? summarizes the condition and forage production of Iranian rangelands and Table ? provides a distribution of rangelands according to province.
Rangeland Classification Iran’s vegetation cover is divided across various geographical areas with respect to climate factors and other ecological conditions. They are:
Khazar (Caspian or Hyrcanian ) Flora This foliage enjoys humid conditions throughout the year according to the prevailing climatic factors. There is no dry period for this flora, or if there is, it is of very short duration. These areas have forests or trees, or forest saplings bearing autumn leaves. In the verdure three ground levels can be discerned: lowland, medium-land and upland. In the lowland area, with the exception of a narrow coastal strip where special annual rangeland plant species grow, there is no significant rangeland or grazing ground growth. Annual Graminae (especially Oplismenus undulatifolius, Setaria spp. ) are much more common than perennial Graminae. Of the latter, the following plants can be mentioned: Andropogonischaemum glomerata, Brachypodium pinnatum and Poa spp. Dactylus. In very dry valleys and slopes are found Aristella bromodes and varieties of Melica, phleum Boemeri spp., Festuca ovina and Stipa spp. Cereal family plants are very low in number while particularly prominent are species of clover, annual or perennial Trifoloium, and several kinds of the perennial genus Onobrychis. Medium lands with altitudes of between 800 to 2,000 meters enjoy the maximum suitable atmospheric heavy rainfall, and in the areas receiving direct sunlight, rich varieties and species of perennial plants are produced including: Dactylis glomerata, Brachypodium sylvaticum, Poa spp., Bromus spp., Melica spp, Agropyron Panormitanum, Aristella bromoides, Festuca montana and phleum bocmeri. Forage plants of the cereal family are very rare and include the following species: red clover, Trifoloium pratense, and white clover Trifolium repens and lotus corniculatus and Coronilla spp., and Cypress Onobrychiss spp. In very high altitude regions it is possible to find thorny Astragalus which is one of the elements of Irano-Turanian flora. High elevations (from altitudes of 200 to about 2,700 meters have a very dry and very cold climate and an resemble semi-steppe high-altitude ranges. Grass growth everywhere is very rich, but differs according to the level of precipitation, soil and general conditions of the land. Gray perennial Graeminas consist of Dactylis glomerata, Bromus persicus and Festuca spp., Trisetum spp., Poa spp., and Agropyron spp.Forage cereals are almost the same as those mentioned for the previous region but Astragalus is much more abundant. In very dry or eroded regions, hemispherical vegetation related to the high-altitude Irano-Turanian mountains such as Onobrychis cornuta and Astragallus spp.proliferate. In fact, the range area of this region is greatere than its forest region, particularly at the upper heights. Grazing grounds and ranges located above 2,700 meters are of the steppe, or Alp type, and are generally considered part of the Irano-Turanian region. Variety of Users Users of rangelands can be divided into the following three main groups:
Nomadic Herders Nomadic herders are those range managers or livestock owners who during various seasons migrate between summer and winter ranges for feeding their animals. This group is further sub-divided into two classes:
Migratory Nomadic Herders This group is part of the migratory herders, but due to special social conditions, they have a distinct nomadic system and hierarchy, and differ from other non-sedentary herders. The group is inter-related through specific clan, tribal and sub-clan relations, and in the past, they trekked as a group from winter to summer ranges. Ranges were specific, separate and limited for each sub-clan or clan but, in general, the tribal land of any single tribe was specific during an historic era. This group controls about 30 m ha of the country’s rangelands. Most of the tribes migrate limited distances, but there are some, which move from region to region, or even between provinces. In this system most of the tribal families move along with their livestock and their main profession is herding and livestock breeding.
Migratory Non-nomadic Herders This group also migrates for feeding its livestock and uses summer and winter quarters. They do not have however a special tribal social structure and sometimes they trek between winter and summer quarters individually or very rarely in groups. This group is probably the remnants of settled nomads of the past, or peasants who copied the ways of the migratory nomads by adapting to ecological conditions.
Semi-sedentary Headers This group of headers only migrates in one season and usually resides in rural or semi-urban areas. In this season they take their livestock to the winter or summer quarters with the entire family sometimes moving with the herd. In some cases only part of the active herding force migrate with the livestock and they spend the rest of the season working in their place of residence. Their main profession is herding but farming is a complementary activity.
Rural Herders This group’s main form of livelihood is agriculture while herding is a complementary activity. They rarely have more than 100 head of livestock and move them by way of seasonal co-operation to neighboring villages. Usually they employ a shepherd to herd their livestock.
Nomadic Tribes and Traditional Rangeland Management Techniques In view of its ancient history and land topography, Iran was one of the first regions to become populated by nomadic tribes. There are known records indicating that circa 700 BC, the Persian population was divided into six sedentary tribe dwelling villages and towns and two nomadic tent-dwelling tribes who were the forefathers of a number of the present nomadic tribes in Iran. These were the people who took their livestock to the Middle East to sell their cattle, sheep and goats and to trade their surplus production of meat, wool and hides on the flourishing markets of the middle East. These nomadic tribesmen were the first to saddle the horse. They selected seeds of alfalfa from wild plants and planted them extensively around their tents. The Chinese took alfalfa and other fodder crops with them to China on the horses bred and trained by the nomadic tribes of Persia. Nomadic tribes were the ones to discover the medicinal value of many herbs and plants. They were also the first to develop industrialization of crops and learn how to use alizarin and terebinth. Nomadic tribes believed that migration was a source of revitalization and a factor contributing to their prosperity. Hence, they were never attached to a sedentary mode of life and never stayed in one area all year round. They believed that livestock and rangeland were the two determining factors in their life and tried their utmost to preserve and develop them. These migratory pastoralists were very resourceful and were the first to dig wells and use the wheel to bring water to the surface for their animals. These virile, proud and independent nomads lived in harmony with nature and came to terms with its irregularities. Through practical experience, they learned a great deal concerning the principles of natural and environmental sciences. They continued to enrich their experiences and hand them down to their descendants for furthering the harmonies methods of treating the environment. The following section deals exclusively with these nomadic people’s experience in the field of rangeland management. C. Zooplankton Zooplankton constitutes the secondary production in all water bodies. As a whole, the Caspian Sea is not rich in species diversity of zooplankton and their number is limited relative to the area of the sea. There are different reports concerning the zooplankton diversity in the Caspian, such as: Ghasemov (1987) mentioning 315 species and Bagherov (1983) citing 235 species. Generally, marine species are dominant and comprise 72.1% of total species. If some fresh water species of Ural and Volga rivers were included, then the total number would exceed 315 species. Originally, they are endemic, Arctic and Mediterranean regions. The endemic and Arctic species are more abundant in deeper waters while the Mediterranean species are found almost throughout the sea and regarded as Euryhaline species. In the south Caspian, Copepoda are dominant during the year. In spring and summer, they comprise 98.4% and 68.1% respectively. The second abundant group belongs to Celadocera and the third are invertebrates. In winter, different kinds of Calanipda, Hydritemora and Galicilcopes are abundant in coastal waters. Others including Cladocera, Molluscan larvae, Mysids and Gammarids also exist but in small number. The average biomass of zooplankton in the west of the south Caspian has been reported at 0.13 gr/m3. In winter, the average biomass is 0.025 gr.m3 in the west and 0.046 gr/m3 in the east. In the central parts, Copepoda and Mysids are dominant during the winter with an average biomass of 0.097 gr/m3. In summer, average biomass increases to 0.97 gr/m3. The Balanus larvae are the most abundant species of the biomass even more than Copepoda. In the Caspian’s central reaches , the biomass is about 1 gr/m3 and most o of which are Larvae of crabs and crustaceans. In autumn, biomass increases but not in offshore waters. In such a way, the biomass in near shore waters is 0.25 gr/m3 while in 50m depth is only 0.017 gr/m3. Generally, among the all diversities and biomass, Copepoda are the most abundant group of which Eurytemora Grimi, that constitutes 80-90% of the kilka's food regime, is the most abundant species. A list of 34 zooplankton species available in southern Caspian is presented in Table 1 and comprises of Cladocer (20 species), Cirripedia (2 species), Ostracoda, Protozoa, Rotatoria, Foraminifera, and Caelenterata. According to a new survey carried out for Copepoda of the southern Caspian waters, three sub-orders including Calanoida, Cyclopoida and Harpacticoida have been recognized. Calannoids are the main group with five species ( Acartia clausi, Limnocalanus grimaldii, Calanipeda aquae dulcis, Eurytemora grimmi, and E. minor). In spring, Copepoda are the main population. In 1996, the total number of zooplanktons was between 4.8 to 20143 (0.025 mg/m3) in spring, 7812 to 65742 (0.04-0.4 mg/m3) in summer, 10850 to 34406 (0.06-0.2 mg/m3) in autumn, and 4510 to 20576 (0.02-0.1 mg/m3) in winter. Ecologically, Acartia belongs to the Black Sea and Calanipeda is a Mediteranean species. Limnocalanus is an Arctic species and Eurytemora is an endemic to the Caspian. Acartia, which has been transferred to the Caspian since 1980, has been dominant in the coastal waters since 1996. A list of available species and distribution maps of benthos are presented in Table 1 and Fig. 1. D. Zoobenthos The Caspian Sea benthos fauna is divided into four geographical divisions comprising endemic, Mediterranean, Arctic and freshwater species. They consist of micro benthos and macrobenthos. Ghasemor (1978) estimates that the total Caspian benthos species number 885, out of which uni-cellar, nematodes, mollusks and crustaceans are the main groups. Accordingly, ciliata have 305 species, nematodes 52, mollusks 116, amphipods 74 and ostracods have 46 species. The number of species is most abundant in coastal waters (0-50 m) and in deep waters (500-1,025 m) the Arctic crustacean species are found. Bagherov (1983) holds that the total number of benthos in the Caspian is 795 species, out of which microbenthos are 367 species and forms (16 foraminifers, 305 infauna and 46 ostracods ) and macrobenthos are 428 species. He estimates that the number of macrobenthos in the southern Caspian is 145 species (193 middle and 90 north) among which endemic species are predominant. According to Ghasemov (1987), there are about 589 species of benthos out of which 47% (279 species) are ciliata. On the west coast, there are 223 species mostly living in depths of 10-50 m. The dominant species are bivalves (mytilaster, abra and dresisena) which comprise about 70% of the total benthos. The second group belongs to crustaceans among which balanuses (68.3%) and crabs (25.1%) are dominant. The first investigation of zoobenthos along the Iranian coasts of the south Caspian was carried out by Vladimir Sekaya in 1973. He investigated coastal areas of a depth of 0-30 m in the western end of the sea and found many major groups including foraminifers, nereis, nematodes, oligochaetes, ostracods, balanus, comacean, gammarids, crabs, abra, mytilaster, hypania and snails. The highest number was found at a depth of 19 m with 64.1 gr/m2 and at a depth of 24m with 49.2 gr/m2. The lowest number was found in Morghal Bay with 3.1 gr/m2. From a biomass point of view, abra with 40.4 gr/m2, then, cerastroderm with 7.6 gr/m2, crustaceans with 13.2 gr/m2 and nereis with 7.2 gr/m2 were the most dominant species. The biomass of oligochaetes was 0.6, balanus 0.1, comaceans 0.3 and amphartids was 0.8 gr/m2. He calculated the average biomass of zoobenthos in the whole of the southern Caspian as 18.24 gr/m2; the number specimens at 7,995 /m2; and the total biomass from shore to the depth of 100 m, equal to 49250 tons. The most abundant groups were (1) amphartida, (2) abra, (3) comaceans, (4) nereis and (5) cerastoderm respectively. From that, 85.7% were Mediteranean and Atls fauna (crustaceans) and only 14.3% were endemic. Another research was carried out in 1989-1990 by Gilan Fisheries Research Center. This focused on the Sefid Rood estuary down to a depth of 100 m., the following groups were recognized: nereis worm (average 21.09 gr/m2 ), tobifax worm ( 18.13 ), gammarusc (1.18 ) , chraphium (1.65) hypania (1.13 ), cardium ( 148.26 ) , abra ( 46.29 ) and mysis ( 6.8 gr/m2 ). The benthos average biomass was measured 30.61 gr/m2 which is much greater compared to Sekaya’s study. The average biomass in the central part of Babolsar was 15.4 gr/m2 and 8.6 gr/m2 in the eastern coasts in Gomishan and the Torkaman fishing area. Therefore, the benthos biomass decreases gradually from west to east. The investigation of Ghasemov (1987) shows that the biomass of benthos in the whole Caspian decreases from the south Caspian to middle and then to the north. The biodiversity of the south Caspian is also more than upper parts of the sea. Table 1 shows these results. In the latest research on determination of species richness and biomass of benthos, the following results have been obtained: 57 species belonging to major toxa including bivalves (5 species), crustacean (47), polychaetes (4) hyrodinea (1) and other groups (balenus, chironomidae, oligochaeta and nematoda ). polychaetes comprise 38.5% of all benthos and then amphipoda (26%), oligochaeta (16%), cumacea (15.3%), bivalves (3.2) and others 13.4%. The maximum numbers were observed in spring (7,354 /m2) and the minimum in autumn (4,309 /m2 ) The amount of biomass increases from west to east and a decrease from shallow to deeper depths. The average biomass for the whole area was equal to 10.8 (min. 7.6 0- max. 14.4) gr/m2 that is less in comparison to other parts of the sea. In Table ?, the list species identified to date by different researchers are represented. In addition, in Figure ?, the distribution maps of benthos biomass are shown. E. Molluscs, Crustaceans and others Molluscans, especially bivalves and gastropods are among the major groups of mollusks in Caspian Sea. Several studies have been carried out to investigate and identify their biodiversity, distribution and biomass along the southern coasts, since they are regarded as one of the main food sources for many fish species, especially sturgeon fish. So far, at least 50 species of bivalves belonging to 19 genera, and at least 86 species of gastropods belonging to 18 genus have been identified in Iranian side and more research is underway to thoroughly investigate them. The list of these aquatics along with other organisms such as amphipods and decapods are provided in Table ?. F. Fishes In Caspian Sea some 100 fish species have been identified which is less diverse in comparison to open waters. As an example, there are 540 and 180 fish species in the Mediterranean and Black Sea. From the Caspian fishes, clupeidae, cyprinidae and gobidae are the most abundant group and constitute more than 70% of the total. The endemic species belong to clupeidae and gobidae. The first origin of Caspian fish is different. Some such as clupeidae and gobidae are saltwater in nature and the others are originally freshwater species such as acipenseridae, salmonidae, cyprinidae, perch and pikeperch. Acipensers are found all over the sea and there is an established fishery for them in all Caspian littoral countries. Many exotic fish species have been introduced to the Caspian ecosystem, such as mullets and atherinidae. In the south Caspian or the Iranian coastal zone, more than 85 fish species live, a list of which are presented in table 23. Among the different Caspian fish species, acipensers are regarded as a protected species and their utilization is severely controlled by fishery regulations imposed by the government. This consists of size control, fishing reason, tackle restrictions, etc. There is also an intense breeding program for the rehabilitation of the population. A fingerling release scheme has been in place for the past decade. It is an established and important routine for fisheries management. In table 24, statistics for different species are represented, which include kutum, acipensers, salmon, roach, etc. In spite of the fingerling release program the salmon population has not recovered and is still regarded as a rare and over-fished species in the last years. The white fish population has been revived and has led to a catch increase since the beginning of program. This is also the case for other species, e.g. sea bream, pike- perch and roach. G. Birds According to statistics, there are 9,648 bird species in the world, out of which 497 species are found in Iran. 30 of these species have been reported only once or twice in the country, therefore it is certain that Iranian bird species are at least more than 460 species. From these, 140 species are endemic and 95 species are migratory. They leave the country with the onset of autumn and move to warmer regions in other countries, especially Africa. 100 other species are semi-migratory species. From 100 migratory species, 80 migrate to Iran in autumn, especially to the Caspian region, only for wintering. The other 20 species fly over the country and do not remain during winter (Birds of Iran, 1983) It is estimated that there are about 200-250 bird species in the Caspian region, some are native, some migratory or semi-migratory. According to the IUCN checklist, some of these birds are rare or endangered and are protected by law. The Department of the Environment of Iran has accordingly provided a regulatory list for the hunting of birds, especially protected migratory species. The list of at least 250 bird species is provided in annex. This list has been prepared according to the areas they have been found. These areas are protected, therefore it doesn’t mean that these birds are not found somewhere else. |
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