Range expansion of the White-throated Nicator in Zimbabwe

In November 2006 White-throated (Eastern) Nicators (Nicator gularis) were heard at the Munyati River low-level bridge (18º27’S 29º33’E) on the Umsweswe-Empress Mine-Gokwe Junction road, an upstream range extension of 80–100 km (Riddell 2006). A recent record comes from Harare with a sighting in a garden on Ridgeway North (Highlands) on 1 May 2011 (Hyslop 2011) where the bird was separated from the female Black Cuckooshrike (Campephaga flava) by yellow spots on the wings (though the Black Cuckooshrike also has similar markings). This record implies a considerable altitudinal jump (c. 1550 m) as well as a range extension. Rockingham-Gill (2010) lists this species as being rare in the Umfurudzi Safari Area but its presence there would also involve another range extension. Unfortunately, this revised list is derived from many sources and it would have been useful if more data had been provided, particularly as it includes some species not known to occur there. That aside, Hippo Pools is relatively low (740m) and the Mazowe River could provide an avenue of suitable habitat for movement onto the Mashonaland plateau and Harare.

            In the northwest of Zimbabwe, Vernon (1987) reported the White-throated Nicator near Dete vlei just outside Hwange National Park, and suggested it as a candidate for possible species that could occur in the National Park (see Hustler 1986). In November/December 1989 Hustler & Williamson (1990) found it still present in the same area, commenting that it had probably arrived there by moving up the Gwayi River. Subsequently it did indeed move into the National Park, as shown in Riddell (1998), where a bird was seen by N. Robey (pers. comm.) in September 1998 in QDS (Quarter Degree Square) 1826D3, a slight range extension of about 50km.

            The latest range extension has occurred along the Limpopo River where it forms the boundary between Botswana and South Africa. On 4 November 2011 I crossed at Zanzibar/Koperspruit  border post where the river is wider and shallower than it is further upstream, and has islands covered by riparian vegetation.  Whilst dealing with customs at Koperspruit (altitude c.715m, 22°34’S 28°27’E, QDS 2228C2) I heard the loud and distinct calls of a White-throated Nicator emanating from the nearby riverine fringe. This is far from its range as depicted in The Atlas of Southern African Birds (Oatley 1997) and the 7th edition of the Roberts’ Birds of Southern Africa  (Hockey et al. 2005) where it extends up the Limpopo as far as 31°E, some 110km downstream of Beitbridge and about 300+ km from Koperspruit. There is one isolated QDS marked in the Limpopo Province of South Africa, which appears to be 2329B1, just west of Louis Trichardt and presumably in the Soutpansberg Mountains. This is approximately 130km ESE of Koperspruit.

            The Atlas says the White-throated Nicator is not subject to any migration or local movements as far as is known and Hockey et al. (2005) say it is ‘resident’ but it appears that this bird is extending its range along rivers in the region.

References

Hockey, P.A.R., Dean, W.R.J. & Ryan, P.G. eds. (2005).  Roberts’ Birds of Southern Africa, 7th edition.  The Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa.

Hustler, K. (1986).  A revised checklist of the birds of Hwange National Park.  Honeyguide 32(2): 68–87.

Hustler, K. & Williamson, C. (1990).  Some new distributional data for birds in north-west Matabeleland.  Honeyguide 36(3): 146–147.

Hyslop, R. (2011). An Eastern Indicator in Harare. Honeyguide 57(2): 136.

Oatley, T.B. (1997).  Yellowspotted Nicator Nicator gularis.  Pp. 148–149 in: Harrison, J.A., Allan, D.G., Underhill, L.G., Herremans, M., Tree, A.J., Parker, V. & Brown, C.J. eds. The Atlas of Southern African Birds. Vol. 2: Passerines. BirdLife South Africa, Johannesburg.

Riddell, I.C. (1998).  A Hwange record of Yellow-spotted Nicator. Honeyguide 44(4): 222–223.

Riddell, I.C. (2006).  A range extension for the Eastern Nicator. Honeyguide 52(1&2): 64.

Rockingham-Gill, D.V. (2010).  The status of birds in the Umfurudzi Safari Area, especially around Hippo Pools.  Honeyguide 56(2): 109–123.

Vernon, C.J. (1987).  Comments on some birds of Zimbawe. Honeyguide 33(2): 54–57.