16. Notes on the birds and other animals recorded at the Cunene River mouth from 6-8 January 2001 M.D. Anderson*, R.A. Anderson, S.L. Anderson, T.A. Anderson, U. Bader, D. Heinrich, J.H. Hofmeyr, C. Kolberg, H. Kolberg, J. Komen, B. Paterson, J. Paterson, K. Sinclair, W. Sinclair, D. van Zijl & H. van Zijl Northern Cape Nature Conservation Service Private Bag X6102, Kimberley, 8300, South Africa e-mail: mark@natuur.ncape.gov.za *To whom correspondence should be addressed The Cunene River is the third-largest Namibian river, emerging in the Atlantic Ocean approximately 1000 km from its source. The banks of the river do not have extensive riparian vegetation and the lagoon and vegetated islands at the mouth are probably the most biologically productive areas on the lower Cunene River. The mouth and lagoon have been described in detail by Simmons et al. (1993) and Simmons et al. (1998). The Cunene River mouth never supports large numbers of waterbirds, but it is nevertheless an important staging and feeding area for waders, probably as a result of its isolated location along the Atlantic coast. The nearest permanent wetland is Walvis Bay, some 700 km away. The low number of waterbirds can be attributed partly to the relatively small area of the mouth and suitable waterbird habitats. For example, the area of exposed sand and mudflats when the river flow is low is only 125 ha and there are only thin strips of riparian vegetation along the banks and on several small islands (Simmons et al. 1998). Despite the low numerical abundance of waterbirds, the Cunene River mouth regularly supports the second-largest wetland species total in Namibia and 72 species have been recorded. This wetland is recognized as an Important Bird Area because of significant populations of Damara Tern, White Pelican, Chestnutbanded Plover and a few other species (Simmons et al. 1998). Although waterbird surveys have been conducted at the Cunene River mouth during the period 1982–2000 (Ryan et al. 1984; Braine 1990; Simmons et al. 1993), it is less frequently counted than other important Namibian wetlands. The aim of this January 2001 study was to count the waterbirds and terrestrial birds at the Cunene River mouth. The waterbird survey was conducted from 08h15–13h00 on 7 January 2001. We divided into three groups (each comprising three people; two observers and a scribe) and simultaneously counted three separate areas. These areas were (1) the northern and southern beach areas adjacent to the mouth opening, (2) the 1.9 km section of the river from our campsite (17°15'316''S, 11°45'544''E) to the river mouth (17°14'434''S, 11°45'133''E), which included the islands, sandbars, and large lagoon on the southern bank, and (3) the river section from the campsite upstream to opposite the Foz do Cunene (17°16'065''S, 11°47'020''E), a length of 2.3 km. The total straight-line distance of the river that was surveyed was approximately 4.2 km. Simmons et al. (1998) considered the section of the Cunene River up to 4 km from the coast to constitute the river mouth. The waterbird survey was conducted with the aid of binoculars and spotting scopes. Although we did not have a boat and thus were not able to access the islands and the Angolan bank, an attempt was made to survey these areas from the southern bank. Nevertheless, it is likely that many birds present on the northern bank, islands and reedbeds were not counted and the results of the survey therefore represent a minimum species and population estimate. All terrestrial birds were also counted during the waterbird survey and additional species recorded during the duration of our three-day stay were also noted. For some waterbirds, such as White Pelican, we conducted additional counts in order to obtain maximum numbers for these species. Notes were also kept of all mammals and reptiles observed. Dirk Heinrich set up seven mistnets on the mudflats, reedbeds and a small accessible reedbed island throughout the three-day period. On some occasions, strong southwesterly winds prevented continuous netting operations and the nets were then closed. All captured birds were weighed, measured, ringed and released. During the survey a total of 2452 birds of 61 species were recorded (Table 1). Waterbirds significantly outnumbered terrestrial birds, with only 155 individuals of 20 different terrestrial bird species being recorded – an indication of the extremely arid nature of the surrounding terrestrial habitats (Table 1). Seven waterbird species were observed which have not been recorded during four previous comprehensive surveys (Ryan et al. 1984; Braine 1990; Simmons et al. 1993), namely Yellowbilled Egret, Dwarf Bittern, Cape Shoveller, African Crake, Wood Sandpiper, Baird’s Sandpiper and Yellow Wagtail. Some species, such as Yellowbilled Egret and African Crake, have been recorded at other localities in the Skeleton Coast Park (Braine 1988). Forty-three species of waterbirds recorded during the previous surveys were not observed during our January 2001 visit. Unusual birds recording during the survey included Baird’s Sandpiper, Royal Tern, Whitebrowed Coucal, Dwarf Bittern and African Crake. During the waterbird survey, two Baird’s Sandpipers were observed along the camp-Foz do Cunene river section and, later that day, one of these individuals was located again and studied in detail which enabled confirmation of the identity of the species. We observed one (possibly two) Royal Terns on two occasions (6 and 7 January), roosting on sandbars in the mouth area. Although no Swift Terns were present, the presence of many Caspian Terns allowed for a comparison between these two similar species. Royal Terns have previously been recorded at the Cunene River mouth (e.g. Ryan et al. 1984; Komen & Paterson 1999). A coucal, possibly Whitebrowed, first recorded at the mouth during November 2000 by R.E. Simmons (in litt.), was heard calling on two occasions during this survey. Forty-nine individuals of 13 species were caught in the mistnets (Table 2), also providing two species (Dwarf Bittern and African Crake) that were not recorded during the waterbird survey. The number of waterbirds recorded was lower than several previous counts (Simmons et al. 1993); this may be due to the time of the survey, especially if the Cunene River mouth is more important as a staging area during early and late summer for Palearctic migrants moving north or south along the south-west African coastline. The number of water and terrestrial birds was nevertheless significantly more than the 1412 individuals of 33 species recorded by Simmons (in litt.) on 10/11 November 2000. A comparison with the numbers of waterbirds reported by Ryan et al. (1984), Braine (1990) and Simmons et al. (1993) reveals higher numbers for several species during our survey, namely Whitebreasted Cormorant, Caspian Tern, White Pelican, Egyptian Goose and Redbilled Teal. Although no effort was made to systematically search for and count mammals and reptiles, Tables 3–4 provides a list of these animals that were incidentally observed during our stay. Acknowledgements The Namibian Ministry of Environment & Tourism is thanked for access to the Skeleton Coast National Park. Dr Rob Simmons provided information on the birds of the Cunene River mouth and commented on this manuscript. Braine S. 1988. Vagrants and range extensions found in and adjacent to the Skeleton Coast Park. Lanioturdus 24: 4–12. Braine S. 1990. Records of birds of the Cunene River estuary. Lanioturdus 25: 38–44. Komen J. & Paterson J. 1999. First specimens of Royal Tern Sterna maxima in southern Africa. Ostrich 70: 242. Ryan P.G., Cooper J. & Stutterheim C.J.1984. Waders (Charadrii) and other coastal birds of the Skeleton Coast, South West Africa. Madoqua 14: 71–78. Ryan P.G., Cooper J. & Stutterheim C.J. & Loutit R. 1984. An annotated list of the birds of the Skeleton Coast Park. Madoqua 14: 79–90. Simmons R.E., Braby R. & Braby S.J. 1993. Ecological studies of the Cunene River mouth: avifauna, herpetofauna, water quality, flow rates, geomorphology and implications of the Epupa Dam. Madoqua 18: 163–180. Simmons R.E., Boix-Hinzen C., Barnes K.N., Jarvis A.M. & Robertson A. 1998. Important Bird Areas of Namibia. In: Barnes, K.N. (ed.). The Important Bird Areas of southern Africa. BirdLife South Africa, Johannesburg. pp. 295–332. Table 1. The number of waterbirds and terrestrial birds recorded at the Cunene River mouth on 7 January 2001. Common name Scientific Name Number White Pelican Pelecanus onocrotalus  149* Cape Gannet Morus capensis  1** Whitebreasted Cormorant Phalacrocorax carbo  240 Cape Cormorant Phalacrocorax capensis  220* Reed Cormorant Phalacrocorax africanus  1 African Darter Anhinga rufa 1 Goliath Heron Ardea goliath  4 Little Egret Egretta garzetta  9 Yellowbilled Egret Egretta intermedia  1 Dwarf Bittern Ixobrychus sturmii  1 Greater Flamingo Phoenicopterus ruber  42 Egyptian Goose Alopochen aegyptiacus  77 Redbilled Teal Anas erythrorhyncha  5 Cape Shoveller Anas smithii  7 Osprey Pandion haliaetus 1 Yellowbilled Kite Milvus parasitus  1 Peregrine Falcon Falco peregrinus  1 African Crake Crex egregia  1 Black Crake Amaurornis flavirostris 1 Purple Gallinule Porphyrio porphyrio  1 Ringed Plover Charadrius hiaticula  70 Whitefronted Plover Charadrius marginatus  48 Chestnutbanded Plover Charadrius pallidus  9 Threebanded Plover Charadrius tricollaris  4 Turnstone Arenaria interpres  1 Common Sandpiper Tringa hypoleucos  6 Wood Sandpiper Tringa glareola  2 Common Greenshank Tringa nebularia  8 Curlew Sandpiper Calidris ferruginea  20 Little Stint Calidris minuta  889 Baird’s Sandpiper Calidris bairdii  2 ! Sanderling Calidris alba  244 Kelp Gull Larus dominicanus  114* Caspian Tern Sterna caspia  74 Royal Tern Sterna maxima  1 Damara Tern Sterna balaenarum  13 Whitebrowed Coucal Centropus superciliosus  1# Eurasian Swift Apus apus  4+ Bradfield’s Swift Apus bradfieldi  2+ Palm Swift Cypsiurus parvus  1+ Pied Kingfisher Ceryle rudis  6 Olive Bee-eater Merops superciliosus  14+ European Swallow Hirundo rustica  39+ Rock Martin Hirundo fuligula  1+ Pied Crow Corvus albus  42 Tractrac Chat Cercomela tractrac 5+ African Marsh Warbler Acrocephalus baeticatus  4++ Cape Reed Warbler Acrocephalus gracilirostris  1++ Fantailed Cisticola Cisticola juncidis  14++ Blackchested Prinia Prinia flavicans 2 Cape Wagtail Motacilla capensis  14 Yellow Wagtail Motacilla flava  1 African Pipit Anthus cinnamomeus  1 Fiscal Shrike Lanius collaris  2 Masked Weaver Ploceus velatus  3+ Common Waxbill Estrilda astrild  18+ Unidentified waders   5 Total – waterbirds   2297 Total – all birds   2452 *    Indicates highest count during period 6–8 January 2001 **   Recorded passing offshore +    Number of birds present was more than that counted ++   Number of birds present was significantly more than that counted #    Heard calling; species identity not certain !    Record not yet submitted to any rarities committee Table 2. The number of birds caught and ringed at the Cunene River mouth from 6–9 January 2001. Common name  Scientific Name Number  Dwarf Bittern Ixobrychus sturmii  1 African Crake Crex egregia  1 Whitefronted Plover Charadrius marginatus  2 Little Stint Calidris minuta  6 Pied Kingfisher Ceryle rudis  1 European Swallow Hirundo rustica  1 African Marsh Warbler Acrocephalus baeticatus  2 Cape Reed Warbler Acrocephalus gracilirostris 1 Fantailed Cisticola Cisticola juncidis  7 Cape Wagtail Motacilla capensis  1 Fiscal Shrike Lanius collaris  2 Masked Weaver Ploceus velatus  3 Common Waxbill Estrilda astrild  21 Total  : 49 Table 3. Mammals recorded at the Cunene River mouth and along the beach between Möwe Bay and the mouth. Common name Scientific Name Number and comments Gemsbok Oryx gazella Seven individuals observed on the Angolan side on the mouth Springbok Antidorcas marsupialis Eighteen individuals observed on the Angolan side of the mouth; some crossed the river to Namibia Black-backed Jackal Canis mesomelas Tracks observed at the mouth; few individuals seen between Möwe Bay and mouth Brown Hyaena Hyena brunnea Tracks observed at the mouth; one individual observed between Möwe Bay and mouth Cape Fur Seal Arctocephalus pusillus Many singletons along beach between Möwe and mouth; large colony at Rocky Point Heaviside’s Dolphin Cephalorhynchus heavisidii One dead individual on beach; south of mouth Killer Whale Orcinus orca One dead individual on beach; south of mouth Long-finned Pilot Whale Globicephala melaena One dead individual on beach; south of mouth Table 4. Reptiles observed in the vicinity of the Cunene River mouth and between Möwe Bay and the Cunene River mouth. Common name Scientific Name Comments Nile Crocodile Crocodylus niloticus Eight individuals were observed at mouth Green Turtle Chelonia mydas Five individuals observed swimming in estuary Nile Soft-shelled Terrapin Trionyx triunguis Several seen swimming in estuary Horned Adder Bitis caudalis One individual near mouth Western Rock Skink Mabuya sulcata Several near mouth Reticulated Desert Lizard Meroles reticulates Several near mouth Desert Plated Lizard Angolosaurus skoogi Several near Mowe Bay Web-footed Gecko Palmatogecko rangei One individual near Rocky point Kaokoveld Namib Day Gecko Rhoptropus biporosus Several near mouth

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Document posted: 24-Aug-2001