The birds of Fort Fordyce Reserve, Eastern Cape

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Figure 1: Location of Fort Fordyce in South Africa
The plateau at Fort Fordyce (altitude 1400 m) has areas of open grassland where grazing mammals have been introduced (black wildebeest Connochaetes gnou, Burchell's zebra Equus quagga burchellii, red hartebeest Alcelaphus buselaphus caama). Bushbuck (Tragelaphus sylvaticus) and blue duiker (Philantomba monticola) occur naturally in the forested areas; baboon (Papio ursinus) and vervet monkey (Chlorocebus pygerythrus) are present, but no samango monkeys (Cercopithecus albogularis) have been recorded. Caracal (Caracal caracal) is the largest resident predator. Annual rainfall averages 1125 mm (mean over 15 years); summer maximum temperatures range to 42 • C while frost occurs regularly in winter, and snow has been recorded in some years.
Based on surveys of the avifauna since 2007 (Craig 2007(Craig , 2012 we have posed the following questions: 1. Does this patch of Afromontane forest preserve a significant component of forest birds, particularly endemic species, and species of conservation concern? 2. Are these birds resident throughout the year, or is there evidence for seasonal movements?

Methods
Since May 2007, we have visited Fort Fordyce on 47 occasions, mostly single day visits. On each occasion, at least two observers have followed a regular route within the forest and across the grassland area, recording all birds seen and heard. These data have been submitted to the Southern African Bird Atlas Project (SABAP2). We have also set approximately 100 m of mist nets along a track near the reserve office and chalets ( Figure 2). The vegetation here is regenerating scrub-forest, with a small patch of pine trees remaining to the east of the net line. All birds captured have been ringed with standard metal rings issued by SAFRING. Apart from our own data, there are 10 surveys by other observers submitted to SABAP2, and three checklists in the Birds in Reserves Project (BIRP). The reserve straddles two pentads (the 5' x 5' minute map units used for SABAP2), including the NW corner of pentad 3240_2630 and the NE sector of pentad 3240_2625 (SABAP2, accessed 13 December 2017). However, virtually all data collection has been within the map unit 3240_2625.
Prior to 2007, we visited the reserve on three occasions (September 1988, April 1989, August 1997 during student field trips lasting 3 days each. Birds were mist-netted, and species lists recorded for each visit; these data are discussed separately. Data are also available from the first bird atlas (SABAP1, Harrison et al. 1997), but the mapping unit at that time was a "quarter degree square" (15' x 15'), which covers a larger area than the reserve and thus incorporated the valley with dry thornveld vegetation. This is evident from the species list, which includes many taxa which have not been recorded subsequently when surveys were restricted to the forest and grassland areas within the reserve.

Avifauna
The SABAP1 list for the quarter degree square (map code 3226CB) incorporating Fort Fordyce Reserve has 211 species, but as noted above some of these are clearly birds of the low thornveld areas at the base of the pass which leads up to the plateau. Nevertheless all 86 species noted by AJFKC and PEH in the years 1988-1997 are included in the SABAP1 tally. The current list for the pentad 3240_2625, based on SABAP2, our surveys and mist-netting records, and the few additional BIRP data, is 175 species (Appendix 1); 18 of these species were not recorded during SABAP1. Three species recorded in the forest/grassland habitats in the period 1988-1997 have not been reported in this sector since then: spotted eagle-owl (Bubo africanus), longbilled pipit (Anthus similis) and golden-breasted bunting (Emberiza flaviventris). Of these, only the owl may be present regularly, since with few overnight stays, nocturnal birds are certainly under-reported; the other two species are likely to be occasional vagrants. For comparison, in three KwaZulu-Natal Afromontane forest reserves, Symes et al. (2002) recorded a total of 136 species, with no more than 110 species at any one site. However, these surveys extended over only 2-4 years at their study sites.

Species of conservation concern
Table 1 lists those species recorded at Fort Fordyce, which feature in the most recent "Red Data Book" for southern Africa (Taylor et al. 2015). The frequency with which these species have been recorded (cf. Appendix 1) suggests that most are only occasional visitors to the reserve. The endangered Cape parrot (Poicephalus robustus) has roosted here occasionally, but the large flocks seen feeding on pecan nuts on farms in the valley at certain seasons fly east in the direction of the Hogsback forests each evening (pers. obs.). Only the Knysna woodpecker (Campethera notata) is a confirmed breeding resident; the African crowned eagle (Stephanoaetus coronatus) probably also nests within the protected area, and the lanner falcon (Falco biarmicus) and bush blackcap (Lioptilus nigricapillus) may do so. There are historical records of southern ground hornbill (Bucorvus leadbeateri) from this site, but none within the past 50 years.

Forest birds
The forest bird species in Table 2 are based on Skead (1967), who listed 74 species which occur in forest in the Eastern Cape, including riverine forest. However, of the species on his list, some do not extend as far west as the Kei River (e.g. eastern bronze-naped pigeon Columba delegorguei) or are restricted to coastal forests (e.g. red-capped robin-chat Cossypha natalensis), but we have included Barratt's warbler (Bradypterus barratti) which he described as found "in scrub adjacent to forests" (Skead 1967 p. 81).   Based on current distribution data in "Roberts VII" (Hockey et al. 2005), 66 species could occur in montane forests along the Amathole Mountain chain, and of this total, 56 have been recorded at Fort Fordyce to date. This is a significant proportion of the South African forest avifauna. Symes et al. (2002) found no significant seasonal variation in forest-specific or forestendemic and near-endemic species during their surveys; 27 of their 33 "forest-specific" species were recorded at Fort Fordyce and none of these showed any seasonal pattern in occurrence.

Seasonal occurence
How effective are visits spread over different months in different years at detecting patterns of seasonal occurrence? This can best be assessed by examining the records of known migrants in our database. Whereas the jackal buzzard (Buteo rufofuscus) has been seen in every month of the year, the steppe buzzard (Buteo vulpinus) has been recorded only from October to February. Four cuckoo species (African emerald Chrysococcyx cupreus, black Cuculus clamosus, Klaas's Chrysococcyx klaas, and red-chested cuckoo Cuculus solitarius) have all been recorded for each of the months October to February; only Klaas's cuckoo has been recorded at other times (March and April), and this species is known to overwinter in small numbers. The black saw-wing (Psalidoprocne pristoptera) and white-rumped swift (Apus caffer) have both been recorded in every month from September to March, with no records from April to August. A similar pattern is found in the three swallow species (barn Hirundo rustica, greater striped Cecropis cucullata and lesser striped swallows Cecropis abyssinica), with no winter records for any of them. This suggests that our sampling should be adequate to detect presence/absence of most species. What can we deduce about the forest birds as listed in Table 2? Apart from the cuckoos mentioned above, only one of these forest species, the African paradise flycatcher (Terpsiphone viridis) (Figure 3), is primarily migratory in our area, and the records seem to reflect this with no reports from May to August -whereas the blue-mantled crested-flycatcher (Trochocercus cyanomelas) has been seen in every month of the year. For some species, however, we currently have too few records to draw any conclusions; these are discussed briefly below. There are < 5 records for the rufous-breasted sparrowhawk (Accipiter rufiventris), buff-spotted flufftail (Sarothrura elegans), Cape parrot, barn owl (Tyto alba), African wood owl (Strix wood-fordii), tambourine dove (Turtur tympanistria), green wood-hoopoe (Phoeniculus purpureus), scalythroated honeyguide (Indicator variegatus), bush blackcap (Figure 4), brown scrub-robin (Cercotrichas signata), mountain wagtail (Motacilla clara) and orange-breasted bush-shrike (Telophorus sulfureopectus).

Figure 4: Bush blackcap (Photo Magi Nams)
Of these species, we would speculate that the African wood owl, scaly-throated honeyguide, bush blackcap, brown scrub-robin and mountain wagtail could be rare residents within the reserve; the others are probably occasional visitors, and may be more common in the valleys below. With both summer and winter records for the forest buzzard (Buteo trizonatus), African goshawk (Accipiter tachiro) and African harrier-hawk (Polyboroides typus), they could be rare residents or merely irregular visitors.
For most of the other species, we have at least 15 records, while the southern boubou (Laniarius ferrugineus) and sombre greenbul (Andropadus importunus) have been recorded on every visit. Vernon (1989) discussed forest birds in the East London region, and mentioned six species with regular altitudinal movements between inland forests and the coast: grey cuckooshrike (Coracina caesia), bush blackcap, Cape robin-chat (Cossypha caffra), white-starred robin (Pogonocichla stellata) ( Figure 5), Barratt's warbler and yellow-throated warbler (Setophaga dominica) ( Figure 6). The question of altitudinal movements has been discussed in more detail elsewhere (Craig and Hulley in press); it will be summarised briefly here. There is a winter record of bush blackcaps from Grahamstown (Craig 1986), while Vernon (1989) noted that a high proportion of his observations of grey cuckooshrike, Cape robin-chat, Barratt's warbler and yellow-throated warbler at the coast were from the months Apr-Sept. Thus it is surprising that at Fort Fordyce all our records of Barratt's warbler are from this period (Apr-Sept), with no summer records to date. Vernon (1989), however, commented that in some years birds may not leave the montane forest, and for the white-starred robin, studies elsewhere have suggested that only a part of the population undertakes regular altitudinal movements (Oatley 1982, Dowsett 1985. At Fort Fordyce, we have recorded grey cuckooshrike, Cape robin-chat and yellow-throated warbler throughout the year, while for white-starred robin there are records for 10 months (Appendix 1). Chorister robin-chats (Cossypha dichroa) have been recorded in every month; Vernon (1989) categorised this species as resident, although Johnson and Maclean (1994) listed it among altitudinal migrants in KwaZulu-Natal. A chorister robin-chat ringed in July at Fort Fordyce was caught again in July the following year, confirming that some birds do stay through the winter.

Ringing
During visits up to 1997, 65 birds of 21 species were ringed. Since 2007 we have ringed 510 birds of 56 species (Appendix 2), thus capturing 32% of the species recorded, and 59% of the forest specialists (as listed by Symes et al. 2002, Brown 2006. We have recaptured 50 individuals (almost 10% of the ringed birds) from 17 species, with the oldest records an olive thrush (Turdus olivaceus) and a black-backed puffback (Dryoscopus cubla), both eight years after ringing. A green-backed camaroptera (Camaroptera brachyura), yellow-throated warbler, southern double-collared sunbird (Cinnyris chalybeus) and Cape white-eye (Zosterops virens) have been recaptured after more than six years, and a white-starred robin after four years. Few birds have been handled more than twice (Table 3); apart from the white-starred robin, these are all species for which our observations indicate that some birds, if not the same individuals, are present throughout the year (cf. Appendix 1). It is interesting to compare our ringing results with those of other ringers operating in forest sites in South Africa.
Also in Afromontane forest, Symes et al. (2002) ringed 403 birds at two inland forest reserves (Hlabeni and Ngele) in KwaZulu-Natal, capturing about 35% of all the species observed there, but > 50% of the forest-specific species. This paper provided no further details on the individual species ringed, nor information on recaptures. In a coastal forest reserve (Umdoni Park) in KwaZulu-Natal, Brown (2006) ringed 466 individual birds of 44 species, which comprised only 23% of the species recorded at this site, but again > 50% of the forest-specific species. Over a five-year period, Brown (2006) recaptured 8.6% of the birds ringed. His most-ringed species by far were bronze mannikin (Lonchura cucullata) and red-backed mannikin (Lonchura nigriceps) (neither of which occur at Fort Fordyce), followed by red-capped robin-chat and olive sunbird February 2, 2020 ISSN 2219-0341 (Cynomitra olivacea) (both restricted to coastal forests in the Eastern Cape), brown scrub-robin and green-backed camaroptera. Williams (2016) described an eleven-year ringing study in an Afromontane forest patch on the Drakensberg escarpment in Mpumalanga. At this site, 384 birds of 43 species were ringed, and 53 individuals of 10 species recaptured. The most frequently ringed species were Cape robin-chat, black-backed puffback, Knysna turaco (Tauraco corythaix), chorister robin-chat, Cape batis (Batis capensis), green-backed camaroptera, blue-mantled crested flycatcher and terrestrial brownbul (Phyllastrephus terrestris) (all > 20 individuals).
All of these species (except the blue-mantled crested flycatcher) have been captured at Fort Fordyce, and all were found to be present throughout the year. However, whereas Williams (2016) captured only 9 sunbirds of five species, at Fort Fordyce the southern double-collared sunbird was one of our most-ringed birds (> 40 individuals). We also caught far more sombre greenbuls than terrestrial brownbuls (see Appendix 2), the reverse of Williams (2016) capture rates; this could be influenced by net positioning at the two sites.

Conclusions
A significant proportion of the regional forest avifauna is found within the Fort Fordyce reserve, and some individuals of all species appear to be present throughout the year. Ringing to date has produced no evidence of movement between this protected area and other localities. While we currently lack good information on breeding status, and breeding success, of these forest species, it is clear that this reserve constitutes a valuable conservation area for forest birds in the Eastern Cape.