On the range expansion of the Magpie Mannikin at Victoria Falls, Zimbabwe

The Magpie Mannikin (Spermestes fringilloides) was reported from Victoria Falls, Zimbabwe by C. von Chamier whilst atlassing for the Southern African Bird Atlas Programme (SABAP2) and the record generated an out of range form for pentad 1755_2550 from the Avian Demography Unit at the University of Cape Town.  A pentad is the unit of data collection formed by five minutes of latitude by five minutes of longitude, ‘squares’ with sides of roughly 9 km.  The first atlas project (SABAP1) took place from 1987–1991, mapping done on a scale of 15 minutes of latitude by 15 minutes of longitude called a quarter degree square or QDSExternal link.

The sighting was of a group of 7 birds, 5 adults and 2 juveniles, photographed near the Kingdom Hotel on 7 July 2014.  C. von Chamier also photographed a single adult at Gorges Lodge downstream of Vic. Falls in pentad 1755_2555 on 11 August 2012.  D. Tiran (pers. comm.) has been seeing the Magpie and Red-backed Mannikin (Spermestes bicolor) at Victoria Falls for the past five years, usually near the Boat Club and National Parks cottages, and heard overhead during the cool and hot dry season (June to November), and says that both species are not resident.

The presence there of Magpie Mannikins represents quite a leap from their known range in Zimbabwe, but perhaps this population originates from southwest Zambia where recorded at Ngambwe Rapids (17°15’S; 24°08’E) on the Zambezi River (Dowsett et al. 2008).  This would entail a downstream movement of c.250 km by river or c.190 km as the mannikin flies.  The mannikin is known for its erratic and nomadic occurrence and this has been linked to the flowering of the indigenous Bindura Bamboo (Oxytenanthera abyssinca), the seeds of which are a favoured food (Jackson 1972). Apart from the eastern highlands, the Mazowe valley, the Manyame valley north of Chinhoyi and the Umniati northwest of Chegutu, there is also an isolate of bamboo marked at Victoria Falls.  Although I am not familiar enough with Victoria Falls to comment as to whether it still grows there the plant has a long life cycle, flowering after some 30 years and then resprouting from seeds, so it is conceivable that it is still present in the area.  This, then, could be enough to draw birds into the area from whatever source, particularly if it has flowered and seeded relatively recently.  In the Harare Botanic Garden they remained associated with the bamboo clumps and immediate area for 5 years (2004-2009) after seeding (pers. obs.).

Magpie Mannikins have not been recorded in the Umniati area, an area probably unfrequented by birdwatchers, but it is also likely that they occur there, even sporadically, where bamboo has been marked on the map.
It should also be mentioned here that D. Tiran’s records of the Red-backed Mannikin (or Black-and-white Mannikin) is also an extension of known range.  The only reference in Honeyguide, the Journal of BirdLife Zimbabwe, is from Field Observations (C. Baker, 2007, 53(1&2): 53–61) where during the last week of December 2005 a group of 6 was seen at the entrance to the Zambezi National Park, Victoria Falls (DT) from where it had not been recorded during SABAP1.  Otherwise, the closest record is from southern Zambia (Dowsett et al. 2008), half-degree square 17° 30’S; 26° 30’E, the centroid of that square being 100 km ENE of Victoria Falls.

References

Dowsett, R.J., Aspinwall, D.R. & Dowsett-Lemaire, F. (2008). The Birds of Zambia. Tauraco Press & Aves, Liège, Belgium.

Jackson, H.D. (1972). The status of the Pied Mannikin, Lonchura fringilloides (Lafresnaye) in Rhodesia and its association with the bamboo Oxytenanthera abyssinica (Munro). Rhodesian Sci. News 6: 342–348.