Sudan,
Sahel zone, Blue Nile, Gezira cultivations, 14º 30’N Annual rainfall 200-400 mm
Irrigation canal and Acacia nilotica trees, Wad Medani
Fields and canal – a typical Gezira
landscape
A vast area (860,000
ha, 8,600 km²) of the arid clay plain on the Gezira, between the Blue and White
Niles, has been converted since 1925 into cereal and cotton production using
gravity-flow irrigation canals from a dam on the Blue Nile at Sennar. The virtually tree-less Gezira landscape supports
large populations of Palaearctic migrants on passage and in winter. Several
thousand Demoiselle Crane, with a few European Crane, forage harvested grain fields
as do thousands of Ruff. Irrigated fields and rain floods attract large
Pratincole flocks and many waders – especially Wood, Green and Common
Sandpipers, and Little Ringed Plover. European Swallow and Swift, and flocks of
Yellow Wagtail variants are regular in autumn. Pallid and Marsh Harriers were
widespread. Less frequent species include: Purple Heron, Squacco Heron, White
Stork (autumn), Glossy Ibis (autumn & spring), Garganey (autumn), Short-toed
Eagle (autumn & winter), Common Kestrel, Lesser Kestrel (autumn), White-winged
Black Tern (both passages), Ringed Plover and Black-winged Stilt, Little &
Temminck’s Stints (autumn & spring), Blue-cheeked Bee-eater (autumn), Sand
Martin, Northern Wheatear, and White Wagtail.
Rarer species: Bittern, Little Bittern, Mallard, Griffon Vulture (north
end), Steppe Eagle (spring, N end), Booted Eagle (winter), Montagu’s Harrier
(spring), Peregrine (autumn), Osprey (spring), Hobby, Saker Falcon (winter, N
end), Honey-Buzzard (spring), European Quail, Caspian Plover, Common Snipe, Black-tailed
Godwit (autumn), Greenshank (autumn), Marsh Sandpiper (autumn), Gull-billed
Tern and House Martin (autumn).
African
inter-tropical migrants: Numerous Cattle
Egret, Sacred Ibis, Abdim’s Stork, and some Black-headed Heron, fed in the
fields when breeding in scattered colonies in village trees during the summer
rains. Carmine Bee-eaters from colonies along the Blue Nile river banks foraged
daily over the fields. All these returned south in late autumn.
Amid
the extensive Gezira cultivations, the large area of garden shrubberies, mature
trees and lawns at the Wad Medani research station provided a veritable ‘oasis’
of cover and feeding habitats for many Palaearctic passerines as well as
resident African species and inter-tropical migrants extending north during the
rains. Palaearctic species wintering here were: Turtle Dove, White Wagtail, Masked Shrike,
Black-eared Wheatear, Common Redstart, Lesser Whitethroat, Olivaceous Warbler,
and Chiffchaff. Regularly passing through in small numbers in autumn were
Spotted Flycatcher and Thrush-Nightingale. Less regular were: Hoopoe, Rock Thrush, Willow
Warbler and Red-backed Shrike. There were single records of: Eurasian
Sparrowhawk, Eurasian Cuckoo, Grey Wagtail, Rufous Bush Chat, Blue Rock Thrush,
Collared/Semi-collared Flycatcher, Common Whitethroat, Garden Warbler, Golden
Oriole and Cretzschmar’s Bunting. Pallid Harrier occasionally hunted through
the more open gardens.
Most of these species visited my garden (illustrated)
as did some waders when the lawn was flooded: Little Ringed Plover, Green
Sandpiper and Wood Sandpiper (7 together in August). Many of the other
Palaearctic species (listed earlier) passed over on passage or when feeding in
the fields.
Resident African
species at the research station, and noted elsewhere in Gezira, comprised: Black Kite (abundant), Shikra (small Accipiter), White-browed Coucal, Pied
Kingfisher, Blue-naped Mousebird, Palm Swift, White-faced Scops Owl, Grey-cheeked
Woodpecker, Black-billed Wood Dove, Long-tailed Dove, Chestnut Finch-lark, White-headed
Babbler, White-vented Bulbul, Black Bush Robin, three warblers, Common Drongo,
Black & Red Shrike, Pied Crow, Beautiful Sunbird, House Sparrow, Grey
Sparrow, Red-billed Quelea, and 6 other
weavers. Tawny Eagles and non-breeding vultures were ever-present in the sky,
scanning for dead livestock - mainly Hooded, Rűppell’s Griffon and Lappet-faced
with an occasional Egyptian, White-backed and White-headed Vulture.
Exceptionally, a Secretary Bird was seen in the southern Gezira.
The residents
were augmented during the rains by migrants from the south, some to breed but
others being casual visitors. In addition to those already mentioned, these
migrants to the Gezira comprised: Grey Pelican, Reed Cormorant, Darter, Green-backed
Heron, Night Heron, Great White and Yellow-billed Egrets, Wood Ibis, Marabou,
Woolly-necked Stork, Open-bill Stork, Gabar Goshawk, Chanting Goshawk, Red-necked
Buzzard, Bateleur Eagle. Long-Crested Eagle, Harrier-Hawk, Harlequin Quail, Senegal
Stone-Curlew, Blackhead, Wattled & Kittlitz’s Plovers, Pied Cuckoo, Senegal
Kingfisher, Little Bee-eater, Grey Hornbill, Yellow-fronted Tinker-Bird, White-bellied
Barbet, Ethiopian Swallow, Paradise Flycatcher, Abyssinian Roller, Zitting
Cisticola, Green-tailed Starling, Cape Rook, Little Weaver and White-rumped
Seed-eater. Most of the African species also visited or passed over the above
garden.
P.J.Dare 2010
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