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Bulletin Zoölogisch Museum UNIVERSITEIT VAN AMSTERDAM Vol. 15 No. 3 1996 Ornithological news from the Cape Verde Islands in 1995, including records of species new to the archipelago Cornelis J. Hazevoet Stefan Fischer & Gérard Deloison Summary Several bird observations, supplementary to the recently published review of the avifauna of the Cape Verde Islands (Hazevoet 1995), were made during visits to the islands in 1995. Three species new to the archipelago were observed, viz. Phalaropus lobatus, Gelochelidon niloticaand Sterna maxima. Also reported here are extensions in time and space of both residents and migrant visitors. These include summer records of several species of waders, herons and Platalealeucorodia, and range extensions of resident breeding species, e.g. the first records of Alaemon alaudipes from the island of Sal. In addition, some new data on breeding seabirds on the islands of Sal and Boavista are presented. INTRODUCTION known to be annual visitors in small numbers. The Cape Verde islands are an oceanic archipelago situat- Also included here are data on extensions in time and ed in the eastern Atlantic, 460-830 km west of Sénégal, range within the islands of both residents and migrant visi- West Africa. There are 10 islands (of which nine are inhab- tors. During June and July 1995, several Palaearctic and ited) and several uninhabited islets. Comprehensive data Afrotropical migrants were recorded for which there were on status and distribution of the birds of the Cape Verde no records so far in these months. These mainly con- Islands, including data up to February 1994, have recently cerned wader species, but also herons, Spoonbill Platalea been published by Hazevoet (1995). In the course of three leucorodia, gulls and hirundines. Apparently, some non- visits to the islands in 1995, the authors made several breeding birds (particularly waders) stay in the islands dur- observations supplementary to that work. Here we report ing the Palaearctic and Afrotropical breeding seasons. For on observations of rare and scarce species, including migrant visitors trom the Palaearctic, Hazevoet (1995) three species new to the archipelago, viz. Red-necked treated occurrences in June as latest dates while those in Phalarope Phalaropus lobatus, Gull-billed Tern Geloche- August were taken as earliest dates. The few records in lidon refer nilotica and Royal Tern Sterna maxima. It may be July were presumed to to oversummering birds. In noted that it is the latter two species had already been pointed reality, of course, not possible to make such a sharp There and birds out as 'potential vagrant terns' (cf. Hazevoet 1995). distinction in late July may well be early arrivals are no breeding gulls or terns in the Cape Verde Islands while some in June may be oversummering. Data on num- but their occurrence as migrant visitors is considerably bers of wintering waders at five different sites and in differ- more frequent than formerly inferred. For instance, ent months (August-June) were given by Hazevoet (1992 Bannerman & Bannerman (1968) remarked that gulls and a). terns "are for Some are truly conspicuous their absence except supplementary data on breeding seabirds are on the rarest possible occasions", listing the occurrence of also given. Those from the island of Sal clearly demon- four species of gulls and only one tern. In marked contrast, strate the continuous and disastrously high pressure from six species of gulls and seven species of terns have now human persecution to which seabirds in the Cape Verdes been recorded in the islands and several of these are now are subjected. Nowadays, the seabird populations of Sal 22 of inevitable if this have almost vanished and only a tiny fraction of the large a collapse the population seems prac- colonies that once existed there does survive (cf. Haze- tice continues. voet 1994, 1995). In this connection, the need for long- laws and Red-billed Phaethon aethereus term educational programmes, new protection Tropicbird of more rigorous enforcement existing laws remains an urgent topic in the islands. On 5 March, 3-5 pairs entering nest holes were observed The opportunity is taken here to point out two errors at Ponta da Fragata, along the southeastern coast of Sal, Hazevoet and Santa Maria that have crept into previous publications. (1992 teenagers at were carrying downy young, b) mentioned "a ringing recovery of a Swedish bird of said to be taken at Ponta da Fragata, on 26 March (F.W. which further details are lacking at present" of Common Wenzel in lift. 1996). This breeding locality had not been fact concerned the in before. A of de Rabo de Tern S. hirundo. In this recovery April reported pair was seen west llhéu in the Hazevoet the 23 1979 on Sal mentioned same paper (cf. Junco, along western coast of Sal, February (F.W. 1995). In Hazevoet (1995) the observation of two Spoon- Wenzel in lift. 1996). None were found there, however, bills P. leucorodia, 23 April 1963, on Santiago should be during a visit on 19 June (CJH). The only recent reports of deleted as this concerned the observation at that date on the species from Sal were of 1 -2 pairs and a bird on the Boavista, correctly listed as such in the check-list's species nest at llhéu de Rabo de Junco in January 1965 (Naurois account. & Bonnaffoux 1969), and a dead bird found along the Dates of the visits in 1995 were as follows: 17 Janua- northeastern coast in April 1991 (Hazevoet 1995). ry-6 February (SF, together with Wolfgang Màdlow and On Boavista, a total of up to 16 birds (some entering Christiane Quaisser), 18 June-10 September (CJH), and holes and cavities in cliffs) was observed at Praia da Fati- 18-31 July (GD). Islands visited were Sal, Boavista, ma and at Ponta do Sol, along the northwestern coast, 29 Santiago, Santo Antâo, Sâo Vicente, and Sâo Nicolau. In January-1 February (SF). This seems to confirm local addition, some unpublished information, kindly supplied by information of breeding along the northwestern coast (cf. Samuel Gomes and Frederick Wenzel, is also incorporat- Hazevoet 1995). Elsewhere on Boavista, the only site ed. Unless stated otherwise, all dates herein refer to 1995. which possibly still has a few breeding pairs is at llhéu de Species new to the Cape Verde Islands are marked with Curral Velho, off the southern coast, where two specimens an asterisk. General data on status and distribution within were collected in 1924and a few birds sighted in 1985 and the islands, as well as those on population size of local 1993. None were seen there, however, on eight visits dur- breeders and earliest and latest dates of migrant visitors, ing the years 1986-1992 (CJH). Apart from those on Sal mentioned there are taken from Hazevoet (1995), to which the reader is and Boavista above, are breeding sites also for further details llhéus do Rombo and Raso. At referred on habitats, climate, geog- on Santiago, Brava, pre- raphy, etc. of the Cape Verdes. sent, the total Cape Verde population does not exceed 100-125 pairs, compared to at least c. 1000 pairs some 100 years ago (Hazevoet 1995). NOTES ON SPECIES Brown Booby Sula leucogaster Cape Verde Shearwater Calonectris edwardsii Only one was present at llhéu de Rabo de Junco, Sal, 20 February (F.W. Wenzel in litt. 1996), and 2 non-breeding During a visit to llhéu de Rabo de Junco, a small rocky adults there, 19 June (CJH). However, the considerable islet off the western coast of Sal, on 19 June, only three amountof white-washat the site indicates a formerly much information from occupied nests (with birds incubating) and one abandoned larger population. The only other recent nest could be Sal is of 10 birds at llhéu de Rabo de Junco in (containing egg shells) found (CJH). This is c. January the only known colony on Sal. There was no information 1991 (Hazevoet 1995), and regularly up to 20 there in The from this locality since September 1965, when c. 40 pairs March-April 1991 (F.W. Wenzel in litt. 1996). breeding Sal were reported (Naurois & Bonnaffoux 1969). Presumably population on is apparently almost wiped out and it due to continuoushuman persecution, this colony has now seems questionable indeed if any young at the Rabo de Main almost vanished. C. edwardsii was the most numerous Junco colony survive to fledge. colonies are on species among subfossil bone remains collected at a pre- Santiago, Brava, llhéus do Rombo, Raso, and islets off historic seabird colony (8th century according to radiocar- Boavista. At present, the total Cape Verde population does bon dating) in the southeast of Sal, indicating that it was not exceed c. 1000 pairs, compared to c. 10,000 at the once a common breeder on the island (Boessneck & end of the 19th century (Hazevoet 1995). Kinzelbach 1993). Main colonies of this endemic species are now found on Brava, Branco and Raso, with some Cattle Egret Bubulcus ibis scattered colonies elsewhere. During the early 1990s, the total but this Two the farm 13 population was estimated at c. 10,000 pairs at sewage on Sâo Vicente, July (CJH), that least 21 and six figure may be too optimistic. It is thought at c. one near Assomada, Santiago, July, at Tarrafal, local fishermen each and 23 These 7500 nestlings are taken by year Santiago, July (GD). are the first July records 23 and the species has now been recorded in all months Ribeira do Calhau, 30 January (SF). No proof of breeding except August. The Cattle Egret is a common Afrotropical on Boavista has been published so far and the species' migrant visitor, mainly from December to April.