Eastern Redfooted Kestrels by 15:1, While They in Turn Outnumbered Western Red- Footed Kestrels by 62:1 (Tarboton & Allan 1984)
262 Falconidae: falcons and kestrels
towns. Large numbers are often associated with termite emergences, locust swarms, and crops harbouring various beetles and other insects (e.g. Mendelsohn 1979). Movements: It arrives in most of southern Africa in early November and about a month later (early December) in the southernmost regions (Zone 8). The last birds depart by early May in most areas but by mid-March in the southern- most regions. Its migration between southern Africa and eastern Asia is one of the longest undertaken by any raptor. After breeding, it flies westwards across India south of the Himalayas, crosses the Indian Ocean to make a landfall in East Africa and continue southwards to the nonbreeding range well south of the equator. Return migration is along a more northerly route (Del Hoyo et al. 1994). Interspecific relationships: Eastern and Western Red- footed Kestrels have their centres of distribution at oppo- site sides of southern Africa, the latter being common in dry and lightly wooded regions in the west. Because the two often occur in mixed flocks, this replacement is more likely to be due to their having different habitat prefer- ences, rather than competitive exclusion. In the Transvaal, Lesser Kestrels outnumbered Eastern Redfooted Kestrels by 15:1, while they in turn outnumbered Western Red- footed Kestrels by 62:1 (Tarboton & Allan 1984). At night, these three species aggregate in large roosts in tall trees, often numbering tens of thousands of birds. Historical distribution and conservation: Irwin (1981) suggested a decline in Zimbabwe, stating that one well- known roost had declined from 40 000–50 000 birds to 8000–12 000, and subsequently to none (A.J. Tree in litt.). There is, however, no consistent evidence for large-scale changes in the distribution and numbers in southern Africa. The grassland regions it inhabits are under intense pressure, mainly from agriculture and commercial afforestation, and the Eastern Redfooted Kestrel should be monitored closely, Eastern Redfooted Kestrel especially as southern Africa probably encompasses most Oostelike Rooipootvalk of the nonbreeding range. Falco amurensis J.M. Mendelsohn
The Eastern Redfooted Kestrel (Amur Kestrel) is a Pale- arctic migrant to southern Africa. The distribution map Recorded in 739 grid cells, 16.3% shows that it is most abundant in eastern South Africa and Total number of records: 4682 in northeastern Zimbabwe. Outside these regions, records Mean reporting rate for range: 7.1% are scattered and sparse. There is a stronghold of particu- larly high reporting rates in the southeastern Transvaal, western KwaZulu-Natal and the northeastern Free State. Outside of the atlas region, it also migrates to Mozam- bique, Zambia, Malawi and southern Tanzania (Benson et Reporting rates for vegetation types al. 1971; Benson & Benson 1977; Britton 1980). It was % 0510 recorded for the first time in the southwestern Cape Prov- ince (separate records in grid cells 3420BB and 3421AB) Miombo 9.2 in December 1992 (Allan 1994c). Mixed Grasslands 8.7 During the northern summer it breeds in the south- Sour Grasslands 6.6 eastern Palearctic in a broad zone stretching from Lake E Zimbabwe Highlands 4.8 Baikal in southeastern Siberia, east and south into Manchu- Moist Woodland 3.4 ria and China (Del Hoyo et al. 1994). Arid Woodland 3.3 In southern Africa it is conspicuous, so reporting rates Sweet Grasslands 3.3 are likely to accurately reflect relative abundance. They usu- Alpine Grasslands 2.6 ally occur in flocks, often numbering hundreds, perching Mopane 2.2 prominently on trees and telephone wires, and hovering Northern Kalahari 0.9 over open fields and grasslands. These flocks often include Okavango 0.6 Lesser F. naumanni and, in northwestern regions, Western East Coast Littoral 0.6 Redfooted F. vespertinus Kestrels. Grassy Karoo 0.5 Habitat: It largely inhabits open and high-rainfall (sour) Central Kalahari 0.4 grasslands, although it is also found in open areas in wood- Valley Bushveld 0.2 land. It often forages in crop-farming regions and roosts in Nama Karoo 0.1 Falconidae: falcons and kestrels 263
14û
EASTERN REDFOOTED KESTREL 5 1 18û
22û 2 6
26û
3 7 30û Reporting rate (%) > 12.4 5.9 — 12.4 2.0 — 5.8
< 2.0 34û 4 8 18û 22û 26û 14û 30û 10û 34û
20 1 5 10
20 2 6 10
20 3 7 10
Occurrence reporting rate (%) 20 4 8 10
J ASONDJ FMAMJ J ASONDJ FMAMJ Models of seasonality for Zones. Number of records (top to bottom, left to right): Occurrence: 15, 7, 1, 1, 452, 409, 1226, 38.