Siberian Crane Wintering in Iran

By Yuri Markin, George Archibald, Sadegh Sadeghi Sadegan

Siberian Cranes of the western population, that breeds on the wetlands west of the town of Uvat in western Siberia, spend the winter on the Caspian lowlands of northern Iran. In both the spring and autumn, major resting areas during their 3,500 km migration include the Naurzum Nature Reserve in Kazakhstan and the Astrakhan Nature Reserve in Russia. Both are protected areas. The cranes remain at these staging areas for 1-3 weeks while at other stops they remain only overnight or for a few days. From Astrakhan, the cranes fly along the west side of the Caspian over Dagestan and Azerbaijan. Wetlands in Azerbaijan and near the Ardebil airport in northwest Iran are also brief stopping places.

Two province in Iran border the Caspian Sea ; Gilan in the west and Mazandaran in the east. Siberian Cranes were first reported in lowland area of Gilan in the early part of the 20th century. However, during comprehensive mid-winter waterfowl counts conducted by the Iran Department of the Environment since the 1960s, cranes were not sighted in Gilan. In 1978, a small group of 10-12 cranes were discovered near the coastal town of Fereydoon Kenar in Mazandaran Province. They were wintering on three duck and goose trapping complexes called "damgahs" located on flooded rice fields within a stretch of 6 km. In the Persian language (farsi) "damgah" means “the place where birds are caught in a net".

The largest damgah ( 200 ha ) is near the town of Fereydoon Kenar while the other damgahs are smaller and lie to the west near the villages of Esbaran (25 ha) and Sorkhrud (25 ha). The Siberian Cranes move between these damgahs and occasionally to rice field bordering the damgahs. The cranes usually select ankle deep water where they forage on a variety of aquatic food items including tubers of sedges, small aquatic animals, larvas, insects, seeds and the green vegetation. Typically, they did in the mud for their food.

Each damgah consists of a large acreage of harvested rice fields flooded artificially to 10-30 cm and bordered by a narrow strip of forests with trees standing about 10 m tall. The inner side of the forest strip is lined by a wall of woven reeds standing about 1.5 m, a wall that must be rebuilt annually before the arrival of the migratory birds. Trappers hide in the forest and behind the wall where they manage their ingenious traps. Thousands of ducks, geese and shorebirds rest on the waters of the damgah during the daylight hours. At dusk and at night they fly to other rice fields to feed, protected from hunters by darkness.

The majority of the waterfowl that gather in the damgahs are dabbling ducks. Common Teal, Mallard, and Pintail are the most abundant while Gadwall, Shoveler, Eurasian Widgeon, Garganey are not uncommon. There are lesser numbers of diving ducks including Common and Red-crested Pochards and Tufted Duck. The geese are predominantly Graylags, although there are fair numbers of Greater White-fronted Red-breasted Geese. Flocks of thousands of Black-tailed Godwits, hundreds of cormorants, many egrets and herons, and a variety of raptors also find sanctuary in the damgahs.

The Siberian Cranes

The three damgahs provide sanctuary for Siberian Cranes. From the discovery of the cranes in 1978 until the later 1990s, the population remained at 9-14 birds and usually included one or two juveniles. Within the large damgah near Fereydoon Kenar, pairs defended large territories against the intrusion of other cranes. It appeared that the damgah could only support three-four pairs. The smaller damgahs did not support territorial pairs suggesting they might not be large enough for such a function. However, these damgahs were often used as feeding and roosting sites non-territorial cranes, which were perhaps unpaired and subadult birds. The small damgahs are also used if the cranes are frightened from the large damgah. Because of the space demands of the cranes, the population failed to increase above 9-14 birds. The other cranes might have been forced to use other wetlands on the Caspian lowlands - wetlands where waterfowl are hunted, not trapped. Perhaps mortality of cranes outside the damgahs is partly responsible for the failure of the population to increase despite excellent productivity. The three damgahs were instrumental in the protection of the remnant population of Siberian Cranes.

The territorial behaviour of the Siberian Cranes on the wintering grounds, was instrumental in the discovery of their breeding grounds. Usually the Siberian Cranes remain inside the damgah. However, January of 1996 when two captive-reared male Siberian Cranes were placed in a holding pen near the damgah, the nearby territorial pair tried to attack them. The male of the wild pair was captured in an enclosure built adjacent to the enclosure of the captive birds and satellite radio was saddled on him. That spring his migration was monitored along the west side of the Caspian and then northeast across Kazakhstan and on to vast wetlands west of Uvat, in West Siberia. Through aerial surveys in June of 1996, Russian biologists located a pair of Siberian Cranes. One female and one juvenile were captured and color-banded, and in subsequent years three more birds were color-marked on the breeding grounds. The male captured in Iran was re-captured, his satellite radio replaced and his migration route was traced back to Iran. He followed exactly the same route he had used in spring. A total of six cranes were colour marked in the western population.

After the male was captured on the wintering grounds in 1996, the crane family remained inside the damgah. Subsequent efforts to capture wild cranes on the wintering grounds failed because birds could not be induced to leave the damgahs and researchers are unable to work inside the damgahs because to do so frightens the waterfowl away from the trappers.

Then the population started to decline. The male marked in 1996, was only seen in Iran again during the winters of 1996-1997. One adult female marked on the breeding grounds in 1996 was seen on the wintering grounds for four years, one year in company with a marked juvenile. The population declined to 9 birds in 1996-1997 and 1997-1998 (2 marked birds), 7 in 1998-1999 (1 marked birds), 5 in 2000-2001 (1 marked bird) and to just 3 during the winter of 2001-2002 and 2002-2003 (no marked birds). Aerial surveys over other wetlands in Mazandaran province in 2000 failed to find Siberian Cranes. Comprehensive ground surveys in both Gilan and Mazandaran provinces in 2000 failed to locate cranes.

Damgahs and Trappers

Like the Siberian Cranes, damgahs are also endangered. In former times, there were hundreds of damgahs across the Caspian lowlands. Today there are few. Perhaps the introduction of firearms made it easier to harvest waterfowl by shooting than by trapping.

Each trapper "douma-chee" owns or rents a small portion of the forest "douma" in which he establishes his traps, builds a small shelter for himself "koumeh" and an enclosure for the 20-30 domestic but flight-capable mallards to attract wild ducks. The success of the trappers is predicated upon their skills with domestic ducks and traps, and the presence of large numbers of waterfowl in the damgah near their traps. It is imperative that the inner core of the damgah be a place where the birds remain undisturbed. Paths and roads leading to the damgahs are blocked and sometimes guarded so that only trappers are allowed to approach the damgah. Hunting with guns is prevented within 1-2 km of the damgahs.

In his "douma" a typical trapper has three methods to catch ducks; the fly-in trap (Doumchal), the swim-in trap (Keres), and the aerial nets (Gezer). Over generations, each method of trapping has been meticulously crafted to coordinate the actions and the tools of the trapper with the behaviour of the wild ducks.

Trapping Method 1.The Fly-in Trap (Doumchal)

Behind the woven wall of reeds, a wedge-shaped area of forest is cleared with the large end of the wedge bordering the woven reed wall that lines the inner side of the forest strip, and the pointed end of the wedge extending almost across the width of the forest strip. One side of the wedge is covered by dense forest and bushes, while the forest on the other side is bordered by a woven reed wall behind which a canal leads across the forest strip. Most of the area of the wedge is covered by low bushes. However at the end of the wedge is a small triangular-shaped pond bordered on either side by woven reed walls extended up several meets. The trapper either uses a small boat or a pole to drive a flock of domestic ducks from their holding pen the out along the canal that borders the outer woven reed wall of the wedge. At the end of the canal, the ducks enter a small chamber formed in part by the reed wall that lines the inner side of the damgah. A door is closed to keep the ducks in this chamber. The trapper also enters the chamber and carefully looks out over the top of the woven wall into the core of the damgah. When he sees wild ducks flying near his area, he carefully and skillfully tosses domestic mallards toward them. The domestic duck sometimes joins the wild ducks and leads them back to the small pond at the end of the wedge in the douma. As soon as they land, the trapper pulls a rope which in turn drops a net over the pool. The wild duck is captured and the domestic ducks are rewarded with food.

A woven reed wall borders a triangular shaped and netted-over pond that extends from the inner wall of the damgah towards the koumeh of the trapper. An opening measuring about 2 m wide and 1.5 m high penetrates the inner wall of the danger. On the inside of this opening is a door that can be elevated by a rope to about 5 meters above the water. The domestic ducks are herded down the same channel used for the Fly-in Trap, but rather than being held in a chamber at the end of the channel, a small opening in the wall of that chamber allows them to escape into the core area of the damgah where they join the wild ducks. Eventually, they seek their home and swim or walk through the opening in the wall. Sometime wild ducks follow them. From the comfort of his koumeh, the trapper observes the happenings and at the right moment pulls a rope that drops the reed-covered door. The wild ducks that swan through the opening are trapped. The wild ducks on the other side of the wall cannot observe the trapper harvesting the captured ducks. Around the door and especially inside of this cage, trapper put some food to decoy wild ducks.

Trapping Method 2. The Swim-in Trap (Keres)

Trapping Method 3. Aerial Nets (Gezer)

This method is used to catch mainly common teal that fly from the damgah during a 15-20 period at dusk and that return to the damgah at dawn. It's operation is based on the behavior of the ducks to fly through the lowest, and therefore the easiest, route from the rice fields inside the damgah to areas outside the damgah.

In each douma, the canopy of the forest is cut to create a concave horizon between taller stands at either end. Metal towers with branches of trees tied to their topes to provide camouflage, are placed among the tall trees at either end of this concavity that stretches about 20 meters between the towers. Two or more sets of nets are suspended from ropes between the towers, ropes that pass through pulleys and descend to the trappers who then can elevate or lower the nets.

When a flock of ducks flies from the damgah at dusk or back at dawn, the birds must cross the line of forest that surrounds the damgah. The ducks seek the lowest points on their horizon, which by design of the trappers the lowest part of the concavity between the towers. At just the right second, a rope is pulled and the net is elevated blocking the flight path of the ducks. If the net to pulled too soon, the duck see it and fly above it. If is pulled too late, the ducks fly over the concavity before the net is elevated. When ducks are captured in the pockets of one net, that net is lowered, and the ducks removed while another trapper is looking for ducks that are flying in the direction of his second net. Sometimes two nets are extended between the same two towers. Although this method is used primarily to capture teal, is also works for other species of ducks as well as shorebirds, geese, raptors and cormorants.

Low height nets (Sho Doum / night net)

On the rice fields outside the damgahs, hundreds of low height nets (Sho Doum / night net) elevated on tall poles trap geese, coots and also teals several nights each month when there is total darkness as a result of cloud cover and/or lack of moonlight. Dozens of domestic graylag geese are driven near the nets during the day. They remain there overnight. Their calls attract the wild geese. Although the use of nets to trap waterfowl is illegal in Iran, the rules have not always enforced by authorities, especially in this area.

Conservation Efforts

Since the discovery of the Siberian Cranes by researchers from the Iran Department of the Environment, the population has been closely monitored by the DOE and by local people. It became immediately apparent that the conservation of cranes was predicated upon the conservation of the damgahs and the traditional techniques to trap waterfowl. Although the status quo was maintained at the damgahs, the population of cranes decreased during the past ten years.

In 1993, the Convention on Migratory Species (CMS) in Bonn, Germany, developed an Memorandum of Understanding on the Conservation of the Siberian Crane, whereby nations within the range of the species can collaborate in developing and implementing conservation programs. There are two other populations of Siberian Cranes, a central population that migrates to India and a eastern population that migrates to China. All three flyways are included in the MOU. Most of the range states participated in the meetings convened by CMS in Russia (May of 1994), India (November of 1996), Iran (December of 1998) and the USA (May of 2001).

At the 1998 meeting in Ramsar, Iran, many of the participants together with local people from the range of the Siberian Cranes in Iran, formed a non-government organization, the Mazandaran Crane Conservation Association (MCCA). MCCA's members include many of the waterfowl trappers. In 2001, MCCA received a $50,000 grant from UNEP for conservation efforts with the trappers. These programs continue.

In 2002, GEF/UNEP granted $1,000,000 for conservation efforts for wetlands used by Siberian Cranes in Iran over the 2003-2009 periods. Concurrently, the International Crane Foundation and CMS hope to provide support to Russian and Iranian colleagues for the restoration of the western population of Siberian Cranes through widespread public education and the bolstering of crane numbers through the migration of captive-reared cranes with hang gliders from the breeding grounds of the western population of Siberian Cranes in Russia to their wintering grounds in Iran.

For more information:

Yuri Markin

Oka State Biosphere Nature Reserve

George Archibald

International Crane Foundation, USA

Sadegh Sadeghi Zadegan

Iran Department of the Environment, Islam Republic of Iran