BIRDING IN ETOSHA NATIONAL PARK

Etosha, ‘the great white place’, is enclosed within a National Park c. 400 km north of Windhoek and 120 km south of the Angolan border. The primary feature within the park is the Etosha Pan, a salt pan some 4 760 km2 in size, up to 129 km long and 72 km wide, covering almost one-quarter of the Park. Numerous smaller salt and clay pans exist to the west and north of the main pan, some of which lie just outside the Park boundaries. The Park comprises an area of inland drainage on the great African plateau. Most of the year the pan lies dry, appearing barren and desolate, but during the wet season the pan is inundated with water from the Ekuma and Oshigambo rivers, which drain catchments in former Ovamboland and southern Angola. Inflow from the east through the Omuramba Ovambo may also be important in flooding Fischer’s Pan and the southern ancient river course on the pan. The extent of the flooding is dependent on the amount of rain that falls in the catchment area and not on surface rainfall. In exceptionally rainy years the pan becomes a shallow lake a few centimetres deep. Geologically the area comprises calcareous sand, gravel and limestone with dolomite outcrops in the west. Soils are shallow and alkaline. The temperature is one of extremes rang- ing from below freezing on some winter nights to above 45°C during the day in mid-summer. Pan surface temperatures can then reach 60°C. Annual rainfall averages 300 mm p.a. in the west and 500 mm p.a. in the east.


The vegetation is primarily arid savanna, shrub and thorn scrub in the west, tending towards tree savanna and broad- leaved woodland in the east. Acacia woodland is found throughout the region with mostly Acacia tortilis, A. reficiens and A. newbrownii dominating. Patches of Colophospermum mopane and Combretum spp. are also characteristic of the Park, especially in the eastern broadleaved savanna belt. All these plant species can vary physiognomically from shrub to tree and occur throughout the Park. Dominant grass genera include Anthephora, Enneapogon, Aristida, Stipagrostis, Eragrostis and Sporobolus.


Birds


This Park supports at least 340 bird species. The main pan is of particular importance as large numbers of both Greater Phoeni- copterus ruber and Lesser Flamingo Phoeniconaias minor regu- larly breed here when rainfall exceeds 440 mm p.a. Historical numbers of up to 1.1 million flamingos have been recorded in exceptional rain years. Etosha is one of only two regular breed- ing sites for these species in southern Africa, the other being Sua Pan in the Makgadikgadi Salt Pans (IBA B005) in Botswana. Unfortunately, breeding success is very limited, and the pan cannot be considered to hold a viable breeding population. In recent years the pan has regularly held over 20 000 waterbirds during the wet season. Apart from flamingos, White Pelican Pelecanus onocrotalus and Chestnutbanded Plover Charadrius pallidus also breed here in large numbers in years of good rain- fall. Rarities are also attracted at such times and Slaty Egret Egretta vinaceigula and Striped Crake Aenigmatolimnas marginalis are unusual visitors. The pan and its surrounding grassveld is also good for Palearctic migrants, including important numbers of Blackwinged Pratincole Glareola nordmanni and Caspian Plover Charadrius asiaticus. The pan also supports large numbers of Cape Teal Anas capensis and Redbilled Teal A. erythrorhyncha. Occasionally small numbers of Redwinged Pratincole Glareola pratincola, Saddlebilled Stork Ephippio- rhynchus senegalensis, Wattled Crane Bugeranus carunculatus and Crowned Crane Balearica regulorum occur on the pan in the wet season. Etosha also supports the only breeding popula- tion of Blue Crane Anthropoides paradiseus outside South Africa; a tiny population of about 60 birds known to have declined in the last 10 years.


The Park is particularly rich in raptors with 46 species recorded. It supports all vultures found in Namibia, including Cape Vulture Gyps coprotheres, Lappetfaced Vulture Torgos tracheliotus and the locally rare Egyptian Vulture Neophron percnopterus. Scavengers such as Tawny Eagle Aquila rapax and Bateleur Terathopius ecaudatus are particularly common since they are unaffected by poisons here. Greater Kestrel Falco rupicoloides and Rednecked Falcon F. chicquera breed. Whiteheaded Vulture Trigonoceps occipitalis, Pallid Harrier Circus macrourus, Montagu’s Harrier C. pygargus and Lesser Kestrel Falco naumanni are less common. A host of eagles (12 species) are found here including Martial Eagle Polemaetus bellicosus and the migrant Steppe Aquila nipalensis and Lesser Spotted A. pomarina during the rains. 


Good rains also bring in Chestnut Weaver Ploceus rubiginosus, which form large breeding colonies. The far western woodland (not accessible to the public) holds small popu- lations of endemics and near-endemics including Violet Woodhoopoe Phoeniculus d. damarensis, Carp’s Black Tit Parus c. carpi, Monteiro’s Hornbill Tockus monteiri, Brad- field’s Hornbill T. bradfieldi, Rosyfaced Lovebird Agapornis roseicollis, Rüppell’s Parrot Poicephalus rueppellii, White- tailed Shrike Lanioturdus torquatus, Rockrunner Achaetops pycnopygius, and Hartlaub’s Francolin Francolinus hartlaubi. This western edge of Etosha where Acacia woodland largely gives way to broadleaved woodland is an area of overlap (and confusion) between two near-endemics (Carp’s Tit Parus c. carpi and Rüppell’s Parrot Poicephalus rueppellii) and their widespread southern African congeners (Southern Black Tit Parus niger and Meyer’s Parrot Poicephalus meyeri).


Typical open country species found most commonly around the pan include Kori Bustard Ardeotis kori, Ludwig’s Bustard Neotis ludwigii, Blackbellied Korhaan Eupodotis melanogaster, Burchell’s Courser Cursorius rufus, Tem- minck’s Courser C. temminckii, Doublebanded Courser Smutsornis africanus and all of southern Africa’s sandgrouse species including the rarer Yellowthroated Sandgrouse Pterocles gutturalis and Burchell’s Sandgrouse P. burchelli. Species preferring wooded Acacia and partial cover include Redbilled Francolin Francolinus adspersus, Redcrested Korhaan Eupodotis ruficrista, Monotonous Lark Mirafra passerina, Crimsonbreasted Shrike Laniarius atrococcineus, Whitecrowned Shrike Eurocephalus anguitimens, Kalahari Robin Erythropygia paena, Pied Babbler Turdoides bicolor, Blackfaced Babbler T. melanops, Barecheeked Babbler T. gymnogenys, Barred Warbler Calamonastes fasciolatus, Burntnecked Eremomela Eremomela usticollis, Marico Fly- catcher Melaenornis mariquensis, Whitebellied Sunbird, Nectarinia talatala, Cape Penduline Tit Antho- scopus minutus, Pririt Batis Batis pririt, Scaly- feathered Finch Sporopipes squamifrons, Violeteared Waxbill Uraeginthus granatinus, Shafttailed Whydah Vidua regia, Longtailed Glossy Starling Lamprotornis mevesii and Burchell’s Glossy Starling L. australis. Wher- ever trees are large enough to support their massive nests, Sociable Weaver Philetairus socius and the associated Pygmy Falcon Poli- hierax semitorquatus occur.


Other threatened/endemic wildlife


Threatened mammals occurring in the Park in- clude Leopard Panthera pardus, Cheetah Aci- nonyx jubatus, Elephant Loxodonta africana, Roan Antelope Hippotragus equinus, Black Rhinoceros Diceros bicornis bicornis, and Hartmann’s Mountain Zebra Equus zebra hart- mannae, and the endemic Blackfaced Impala subspecies Aepyceros melampus petersi. The Namibian near-endemic Damara Dik-Dik Madoqua kirkii also occurs here. Efforts to re- introduce African Wild Dog Lycaon pictus have failed thus far. Reptiles include the Afri- can Python Python sebae, Dwarf Python P. anchietae, Kalahari Star Tortoise Psammo- bates oculiferus, Leopard Tortoise Geochelone pardalis and Etosha Agama Agama etoshae.


Conservation issues


Originally established in 1907, Etosha Game Reserve covered 9 324 000 ha; it was gradually reduced to 2 314 000 ha in area between 1947 and 1953. In 1958, it was officially designated a National Park under Section 37 of the Nature Conservation Ordinance 31, and on the recom- mendation of the Commission of inquiry into South West Africa’s Affairs (Odendaal Com- mission), the size of the Park was increased to include sections of the Skeleton Coast, enlarg- ing the area to 9 952 600 ha. By 1970 the Park’s borders had once again been depro- claimed to its current size to provide land to Herero speaking tribes; the size has been re- duced by 72% since 1907.

   

Etosha faces several persistent managementchallenges. It is surrounded on its southern andwestern borders by commercial farmland: double electric boundary fences, primarilydesigned to keep Lion Panthera leo and Elephant in the Park and poachers and domestic animals out of the Park have been erected. This has resulted in serious disturbance to ungulate migratory patterns. In particular, wildebeest migra- tion was blocked by the northern fence, with a resultant decline from 25 000 to 2 300 animals in the space of 25 years. Elephant, however, still migrate out of the Park in the wet season and may then create problems in adjacent commercial and communal farming areas. 


Additionally, many borrow pits were dug during road construction; these pits filled during rains and were assumed for many years to harbour anthrax bacteria. This was later proven incorrect, but anthrax remains a problem, killing many species of herbivore. Another disease, Feline Immune Deficiency Virus (FIV) affects cats, particularly Cheetah. Fire control in the past permitted the transition of the vegetation from

open savanna to woodland, which allowed a concomitant in- crease in Elephant numbers from 100 in 1955 to 1 500 at present. Drought periods between 1979–1996 have further com- plicated issues, as ungulates have been unable to migrate away from drought stricken areas. High predation rates and levels of anthrax serve to reduce ungulate populations well below levels that would be sustained by the available food resources. Many of the Lion dispersing from the Park are shot in the adjacent commercial and communal Districts where they are perceived to be a threat to livestock. The individuals that escape the gun become the famous coastal lions that disperse down the rivers to the Skeleton Coast, where they scavenge on seals and beached whales. Communal farmers in the rivers exterminate these too.


Recent research has shown that while flamingos occur in spectacular numbers, they rarely breed successfully (1 in 9 years) because the water rapidly evaporates, exposing chicks and fledglings to predators and eliminating food sources adjacent to the colony. The low breeding success in the last four decades has shown that the pan does not support a self- sustaining population. Scientific research to find solutions to management problems is conducted through the Etosha Eco- logical Institute, which is located at Okaukeujo.


Further reading


Archibald (1991); Archibald & Nott (1987); Aves (1992); Berry (1972, in press); Berry et al. (1973, 1987); Brown (1992c); Brown et al. (1987); Clinning & Jensen (1976); Fox et al. (1997); Gasaway et al. (1996); Jensen & Clinning (1976); le Roux et al. (1988); Simmons (1996a); Simmons et al. (1996).

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