Birds of the Bloemfontein area, Free State Province, South Africa, during the years 1977-2000: an overview

The aim of this paper is to summarize our knowledge of the birds of the Bloemfontein area, Free State, South Africa. It presents data on the status, distribution, population densities and habitat of the birds of this area, during the years 1977-2000 (with a special emphasis on the years 1993-1998). Both published and unpublished data are analysed. Population densities were estimated mainly using the line transect method and territory mapping method. For most fairly common, common and very common species, data on population densities are provided, while for 19 species (mainly rare or very rare), distribution maps of their occupied territories are presented. A total of 324 bird species were recorded. Breeding birds comprised 60.2% of the overall species (195), while non-breeding birds made up the remaining 39.8% (129). Among the breeding species, most (55.9%) were residents throughout the year, 3.1% were intra-African migrants and 1.2% were nomads. Non-breeding birds were represented by Palearctic migrants (35 species, 10.8%) classified as vagrants, irregular and regular visitors; and African non-breeding species (94; 29.0%), which were mainly vagrants. Among the breeding species, most were rare or very rare (100 species, 56.4%). Only 24 (12.3%) of them were very common, nine of which were non-passeres and 15 passeres. The main threat to birds in the Bloemfontein area is intensive agriculture. Some suggestions and recommendations are given for more effective and efficient bird conservation in this important area.


I. INTRODUCTION
In major ornithological handbooks, data on population density for most African bird species are very limited (FRY et al. 1982(FRY et al. -2004DEL HOYO et al. 1992-2013. This is true even in regard to southern Africa, where ornithological studies have been much more advanced and intense than in other regions of the continent (FRY et al. 1982, HOCKEY et al. 2005. However, data on the population densities of African species have only been partly retrieved from articles and notes, scattered in local and usually, not easily accessible journals. Nevertheless, there is also a real lack of data on the population densities of less common African bird species (and those with larger territories) obtained using larger study plots or longer transects (more than 100 ha for study plots, or at least 10 km for transects), that are representative enough to make reliable estimations (BIBBY et al. 2012, SUTHERLAND 1996. To make the matter even worse, most of the data availaible on the population densities (breeding populations) of African birds refer to the number of individuals per 1 ha (cf. HOCKEY et al. 2005). In population studies, a breeding pair, not an individual, is the census unit (BIBBY et al. 1992, SUTHERLAND 1996. Data referring to the number of individuals (and from such small study plots) are, therefore, of little use for comparisons between different habitats and regions, while those referring to the density of breeding pairs (e.g. TARBOTON 1980, MONADJEM 2002, KOPIJ 2017) are rare. The presented paper attemps, therefore, to partly fill this gap in our knowledge on the population densities of African birds. It provides information on the status of all bird species, as well as the population density estimates for more common species breeding in the Bloemfontein area, located in the central part of South Africa.
The first systematic account of birds in the Free State was published by VAN DER PLAAT (1961). The entire avifauna of the Bloemfontein area was more systematically recorded during the years 1977-82 by ROOS et al. (1985). In the following years , an atlas project was conducted in this and other districts of the Free State by members of the Free State Ornithological Bird Club. The project resulted in an atlas of birds of the Free State province written by EARLE & GROBLER (1987). A similar atlas project (SABAP1) on the birds of all of southern Africa (including the Free State) was held in the following years (1987-92) (HARRISON et al. 1997).
In 1993-1998, quantitative studies were conducted on selected bird species (e.g. KOK & KOPIJ 1994) and on avian communities of selected habitats in the city of Bloemfontein (e.g. KOPIJ 1994). Most of the results from these studies were published in the local Free State ornithological journal -'Mirafra', and were partly summarized in KOPIJ (2001) and KOPIJ (2015). At the same time avian communities were being quantified in other parts of the Bloemfontein area (e.g. KOPIJ 1997KOPIJ , 1998KOPIJ , 2000aKOPIJ , 2002a. Semi-quantitative data on birds of the Botanical Gardens, a popular place for ringing birds on the outskirts of Bloemfontein, were published by DE SWARDT et al. (1992) and by KOK (1996).
Throughout the years 1993-2000, observations of rare bird species were regularly published in the local ornithological journal 'Mirafra'. This project was co-ordinated by R.J. NUTTALL.
This paper presents our knowledge on the status, distribution, numbers and habitat of birds in both the city of Bloemfontein and in the surrounding areas during the years 1977-2000. Special emphasis is paid to the years 1993-1998, when quantitative studies were conducted in various habitats for common species, while for rarer species, censuses were conducted across the whole of the Bloemfontein area. The presented data are, therefore, mainly of historic value, but may constitue a basis for the future monitoring of any changes in the bird fauna of this region of Africa.

II. STUDY AREA
The study area includes the city of Bloemfontein, the Bloemfontein district and surrounding areas. It is situated in the central part of the Free State province of South Africa, between the Mooder River to the north and Riet River to the south (Fig. 1). The area borders the Highveld and the semi-arid Karoo, and lays at an elevation of c. 1400 m a.s.l. The surface of the study area is c. 6500 km 2 . The human population was 747,431 (520 000 in the Greater Bloemfontein region) in 2011.
The natural vegetation in the Bloemfontein area is represented by the Dry Cymbopogon-Themeda Grassveld (Fig. 2). It is composed mainly of grassy plains. The dominant grasses are Themeda trianda and Cymbopogon plurinoides. Also common are the following grass species: Eragrostis capensis, E. curvula, Settaria flabellate, Tristachya leucothrix, Heteropogon contorus, Hypparhenia hirta. The watercourses form valleys which are covered mainly by Acacia karroo in the north (Modder River, Rhenoster River), Salix babylonica (Bloemspruit) in some stretches in the north-east and with sedges, reeds and grasses in the south (e.g. Kaalspruit). In the Bloemfontein area, north-west and east of the city, there are dolorite koppies covered with Olea-Buddleia vegetation.
The average annual rainfall is c. 550 mm. Three quarters of the rain falls during October-March. Summers are mild with average temperatures of 20-25°C. Winters are cold with temperatures ranging between -10°C to +12°C, with frost occurring regularly (Fig. 3).

III. METHODS
This study is based on both published and unpublished materials, reports and observations. Most unpublished data are from the years 1993-1998, when the author was a resident in Bloemfontein.
The following terms were used to describe the status of each bird species: 1) Vagrant: 1-10 records during 1977-2000; 2) Irregular visitor: recorded almost every year or annually, but in small numbers; 3) Regular visitor: recorded annually in large numbers; 4) Intra-African migrant: a resident in the wet season, emi-grating in the dry season to other parts of sub-Saharan Africa; 5) Palearctic migrant: only present in the wet season, emigrating to the Palearctic region in the dry season; 6) Resident: present throughout the year (Table 1).
Whenever possible, data on the population densities from various habitats are also provided for more common resident breeding species. Density is usually expressed as the number of pairs per 10 km (estimated by means of the line transect method) or as the number of pairs per 10 km 2 (=1000 ha) (estimated by means of the territory mapping method). The length of transects or the surface area covered are given in brackets.

IV. AN ANNOTATED CHECKLIST OF SPECIES
The systematics and nomenclature of species follows HOCKEY et al. (2005).

South African Shelduck Tadorna cana
Rare breeding resident at larger dams; common in non-breeding season. Average monthly number of individuals at the Krugersdrift Dam in -1987was 110 (MARX 1992. The largest concentration observed was 2277 moulting exx., Krugersdrift Dam, November/December 1972(GELDENHUYS 1975.

Common Buttonquail Turnix sylvaticus
Probably, a very rare breeding resident in extensive grasslands .
Lesser Honeyguide Indicator minor Very rare breeding resident. During the years 1977-83 only two records were made .

African Hoopoe Upupa africana
Common breeding resident in suburbs, farmsteads, sand river cliffs.

PHOENICULIDAE
Green Wood-Hoopoe Phoeniculus purpureus (Fig. 6) Very rare breeding resident in poplar plantations in river vallies and suburbs. During the years 1977-82, one breeding site was known on the Modder River near Glen . During the years 1993-2000, three breeding sites were recorded.   Dam, 20.10.1994(NUTTALL 1994a.

Malachite Kingfisher Alcedo cristata
Fairly common breeding resident in water courses. The most common kingfisher species. Density: 1.2 pairs/10 km, Modder River (63 km transect) (KOPIJ 2000a). A total of 76 birds were captured for ringing during the years 1993-2005 (N= 10944) at Bishop Glen .

Brown-hooded Kingfisher Halcyon albiventris
Very rare breeding resident in larger water courses.

Diederick Cuckoo Chrysococcyx caprius
Fairly common intra-African migrant; along water courses and in clumps of exotic trees. Density

CENTROPODIDAE
Burchell's Coucal Centropus burchellii ( Fig. 6) Very rare breeding resident in reed beds, in close vicinity to shrubs and water. During the years 1983-86, it was recorded as a resident in the northern part of the district (EARLE & GROBLER 1987). During the years 1993-2000, it was known from three breeding sites.

Alpine Swift Tachymarptis melba
Rare breeding resident in the Bloemfontein city centre; c. 20 pairs in 1997.

African Grass Owl Tyto capensis
Very rare breeding resident in karroid vegetation in close proximity to vleis. Only one record from the Bloemfontein area during the years 1983-87 (EARLE & GROBLER 1987).    ). This species preferres Rhus lancea for nesting sites, but nests were also located in exotic trees, such as Casuarina sp. and Thuja occidentalis (KOPIJ 1998c).

Buff-spotted Flufftail Sarothrura elegans
Probably, a very rare breeding resident at dams with emergent vegetation.
African Rail Rallus caerulescens Very rare breeding resident.

African Snipe Gallinago nigripennis
Rare breeding resident at dams. Common Sandpiper Actitis hypoleucos Regular summer visitor from the Palearctic region.
Ruff Philomachus pugnax Regular summer visitor from the Palearctic region.

Birds of the Bloemfontein area, an overview
Caspian Tern Sterna caspia (Fig. 11) Probably, a very rare breeding resident at large dams. Not recorded before 1993. During the years 1993-2000, single pairs nested at the Krugersdrift and Rusfontein Dams.
Whiskered Tern Chlidonias hybrida (Fig. 11) Very rare breeding resident. 'a number of birds in full breeding plumage', Bishop Glen Dam, 21.10.1995(NUTTALL 1995b. A pair at small pan was recorded on 25.2.1996 and feeding, Soetdoring NR, 6.3.1996(NUTTALL 1996, where they also nested in successive years.
White-winged Tern Chlidonias leucopterus Regular summer visitor from the Palearctic region.

African Harrier-Hawk Polyboroides typus
Vagrant; one possible breeding pair near Glen.
Southern Pale Chanting Goshawk Melierax canorus (Fig. 14) Very rare breeding resident in extensive grasslands with Olea-Buddleia or Acacia karroo vegetation. Two territories were located at Glen and Soetdoring NR.

Black Goshawk Accipiter melanoleucus
Very rare breeding resident in larger old gum tree plantations. An expanding species, recorded for the first time in the Bloemfonteibn district in 1994: an ocupied nest with three chicks was found in Bishop Glen (KOPIJ & ESTERHUIZEN 1994b, BREEDT 1995. In 1997, occupied territory was also recorded in Bain's Vlei.

Greater Kestrel Falco rupicoloides
Rare breeding resident in extensive grassland.

ANHINGIDAE
Darter Anhinga melanogaster Very rare breeding resident in dams and rivers. In 1991/92 summer, a few breeding pairs were recorded at Olive Hills in Soetdoring NR (COLAHAN 1992a).

White-breasted Cormorant Phalacrocorax lucidus
Irregular visitor to dams and the Modder River.

Grey Heron Ardea cinerea
Rare breeding resident at dams and rivers. In 1991/92 summer, a few nests were found at Olive Hills in Soetdoring NR (COLAHAN 1992a).

Black-headed Heron Ardea melanocephala
Rare breeding resident at dams. In 1991/92, summer, a few pairs were recorded at Olive Hills in Soetdoring NR (COLAHAN 1992a).
Goliath Heron Ardea goliath Very rare breeding resident at a large dam with fairly extensive reed beds. In 1972/73, summer, 4 nests were found at the Krugersdrift Dam (GELDENHUYS 1984). In 1993-2000, single pairs were breeding at Bishop Glen (GK). Largest recorded flock size: 30 exx. at the Krugersdrift Dam.

Black-crowned Night Heron Nycticorax nycticorax
Rare breeding resident on the Modder River and at dams with clumps of weeping willows.
Little Bittern Ixobrychus minutus (Fig. 20) Very rare breeding resident in extensive reed beds at dams and some rivers. During the years 1993-1997, two breeding sites were recorded: on the Modder River in Soetdoring NR and in Bishop Glen.

Greater Flamingo Phoenicopterus ruber
Irregular visitor to dams and pans.

Lesser Flamingo Phoenicopterus minor
Irregular visitor to dams and pans, often in the company of Greater Flamingoes.

African Spoonbill Platalea alba
Irregular visitor to large dams; breeding in the past. During the years 1972/73, 3 pairs nested at the Krugersdrift Dam (KOPIJ 1997a).

Pink-backed Pelican Pelecanus rufescens
Vagrant. Only one bird was recorded during the years 1983-86 in the 2926 DA atlas grid (EARLE & GROBLER 1987).

MONARCHIDAE
African Paradise-Flycatcher Terpsiphone viridis Very rare breeding resident in luxuriant suburban vegetation.

Pied Crow Corvus albus
Rare breeding resident in farmlands.

Banded Martin Riparia cincta
Regular visitor to sand river cliffs, mostly on the Modder River.

Brown-throated Martin Riparia paludicola
Fairly common breeding resident in large dongas and sandy river cliffs, mostly on the Modder River.

Red-breasted Swallow Hirundo semirufa
Fairly common breeding resident. It usually nests in large pipes under roads, sometimes under bridges.
South African Cliff Swallow Hirundo spilodera (Fig. 22) Very common intra-African migrant. It nests in large colonies under bridges. In the middle of 1985, 18 colonies were known in the district (EARLE 1985(EARLE , 1987. Most of these colonies were

Little Rush Warbler Bradypterus baboecala
Vagrant. During the years 1993-2005, only one record was made at Bishop Glen .

Sedge Warbler Acrocephalus schoenobaenus
Irregular summer visitor from the Palearctic region. In total, 32 birds were captured for ringing (N= 10944 of all captured birds) at Bishop Glen during the years 1993. Extreme dates: Bishop Glen, 26.11.1994;Bishop Glen, 12.03.1994(NUTTALL 1994b  .

Chestnut-backed Sparrowlark Eremopterix leucotis
Rare breeding nomadic in dry grassland, mainly in the southern part of the district.

Grey-backed Sparrowlark Eremopterix verticalis
Rare breeding resident in dry grasslands in the western part of the district.

Red-capped Lark Calandrella cinerea
Common breeding resident in grasslands, especially overgrazed grasslands; also in farmlands.

Red-headed Finch Amadina erythrocephala
Fairly common breeding resident. First record in the Bloemfontein district was made on 21.7.1985 at the Botanical Gardens (NAUDE 1985). During the years 1993-1998, a dozen or so pairs were recorded in 51 km 2 of Bloemfontein city (KOPIJ 2001).

Blue Waxbill Uraeginthus angolensis
Rare breeding resident in Acacia karroo vegetation.
Red-billed Firefinch Lagonosticta senegala Possibly, a very rare breeding resident. During the years 1983-86, 5 records were made in the northern part of the district (EARLE & GROBLER 1987); a pair was recorded on 2.5.1995 in the Botanical Gardens (NUTTALL 1995).
Village Indigobird Vidua chalybeata Rare breeding resident in Acacia karroo vegetation. During the years 1983-86, it was probably a very rare breeding resident. It was recorded at Birds of the Bloemfontein area, an overview Buffy Pipit Anthus vaalensis Rare breeding resident in dolorite koppies and short grassland. During the years 1983-86, 2 records were made in the 2826CC atlas grid (EARLE & GROBLER 1987); 1 ad., 16.5.1998, Soetdoring NR (DE SWARDT 1998 which could benefit from the expansion of agriculture is the Black-shouldered Kite. Its main prey, rodents (KOPIJ et al. 2004), are abundant on farmsteads where the Kites usually establish their nests. Most likely, the Black-shouldered Kite has markedly increased its number during the last 50 years. Eucalyptus, so often planted on the farmlands in the Bloemfontein area, may also have attracted some goshawk species, such as the Black Goshawk, Red-breasted Sparrowhawk and Gabar Goshawk. This relatively low population density of resident raptors could have been very conducive for Palearctic migrants, viz. the Lesser Kestrel, and Amur Falcon, which overwinter in this area in huge numbers.
In order to protect the remaining raptors, the old tree stands on and around farmsteads should be conserved. It will be especially important to conserve the large eucalyptus trees which serve as roosting sites for the Palearctic migrants. For the more efficient protection of eagles, the regional authorities should create exclusion zones 0.5-1 km around their known nesting sites. The sites should be regularly monitored by nature conservation officers.
More conservation efforts should be also made to protect heronries. These are usually multispecies breeding colonies established around dams or larger water reservoirs. They are often occupied annually for many years. Some of them are disturbed by people, and some have even been destroyed. Such sites, especially those with larger colonies, should be protected as nature reserves.
Raptors are a group requiring special protection in the Bloenfontein area. Conversely, there are also alien invasive bird species which require eradication from this area. Four have established themselves so far; the Feral Pigeon, House Sparrow, European Starling and Indian Myna. The two former species are strictly associated with human settlements, especially in the greater city of Blomfontein. Their negative effect on the local avifauna is therefore limited. However, the European Starling and Indian Myna dispersed into countryside, and may became competitors of the indigenous species. They are currently, relatively uncommon, but may soon spread, causing a sharp population decline and even local extinction in other species.
It is also recommended to establish some sort of protection in the river valleys covered with Acacia karroo vegetation and some of the Olea-Buddleia fields. It has been shown that they usually harbour the highest diversity of bird species, and that many of these species reach their highest population densities in these areas.
Last, but not least, the local university, nature history museum, bird clubs and other proecological societies in and around Bloemfontein should increase their effort to educate the public about the importance of the protection of native birds, their habitats and nature in general. It is especially important that such environmental education reaches the municipalities, schools and the farmers who control most of the land in question. These organizations should also be more involved in the montironing of more important sites (e.g. Bishop Glen, larger dams, water reservoirs and river valleys); breeding colonies of ciconiiforms, the roosting sites of Palearctic raptors and the Barn Swallow, and species important for conservation (e.g. key and umbrella species, but also invasive ones), such as eagles, owls, korhaans, hornbills, wood-hoopoes, coraciforms, cuckoos, Secretarybird, Hamerkop, Sacred Ibis, Baillon's Crake and Buff-spotted Flufftail.