12 
Bulletin of the EANHS 29(1/2) 
than their temperate counterparts He also showed that 
there was a significant decline in Peregrine Falcon 
density with decrease in latitude as well as a decline in 
food availability. It is possible that cliff height also plays 
an important role in the breeding of Kenyan Lanners 
and Peregrine Falcons The low number of Common 
Kestrel pairs can possibly be explained by a lack ol 
mates (thus explaining the two single roosting birds) or 
high predation on kestrels on lower sections of cliff 
Other birds of prey seen along the cliffs at Lake* 
Baringo are probably resident hut not cliff dweller*;. 
These include the Fish fcaglcs. Batelcurs. Gymnogenes 
and Bat Hawks. The Hobby Falcons, Pallid Hamers 
and Steppe Buzzards were probably on migration and 
were all recorded flying in a southerly direction Shikras 
use the cliff lor hunting, especially through the trees 
along the top. or for perching in die trees on the cliff 
face However, the high riverine vegetation in Iron! of 
the cliff would provide suitable nest sites for this species 
Anthony J. vun Zyl. Department of Birds. Transvaal 
Museum. P O Box 413. Pretoria. South Africa 
George Amulete. Ornithology Department. National 
Museums of Kenya. P. O. Box 40658. Nairobi. Kenya. 
Sully T. Newton*. Department of Birds. Transvaal 
Museum. P. O. Box 413. Pretoria. South Africa 
•Present address: Brain Function Research Unit. 
Department of Physiology. University of Witwacererand 
Medical School. 7 York Road. Phrktown. Johannesburg. 
2193. South Africa 
References 
Brown. L (1970). African Birds of Prey. Collins, 
London 
Brown. L. (1980). Vie African Fish Eagle Pumell. 
London. 
Gargett. V (1990). Vie Black Eagle. Johannesburg- 
Acorn. Johannesburg. 
Jenkins. A. (1991) Latitudnuil prey productivity and 
potential density in the Peregrine Falcon Gubar 
6:20-24. 
McCann. K.l (1994) Habitat utilization and lime 
energy budgets of else Lesser Kestrel Rilco natummni 
in its southern African non-breeding range 
Unpublished MSc thesis. University of 
Wi waters rand. Johannesburg 
Sorlcy. C.S. and Andersen. D E (1994) Raptor 
abundance in south-central Kenya in relation to land- 
use patterns. African Journal of Ecology 32: 30-38 
Stevenson. T (undated) The birds of Lake Baringo 
Nairobi: New World Printers. 
Stcyn. P (1982) Birds of Prey of Southern Africa Their 
identification and life histones. Cape Town. David 
Philip. 
Van Zyl, A.J. (1993). Aspects of the ecology of the 
Southern African Kestrel (Falco tinnunculus 
rupicolus). Unpublished MSc thesis. University of 
Cape Town. Cape Town 
SHORT COMMUNICATIONS 
OBSERVATIONS OF DODDER ( CUSCUTA 
CAMPHESTRIS YUNCKER) PARASITISM ON 
HEDGES IN NAIROBI 
Although most plant diseases arc caused by fungi, 
bacteria, viruses, and nematodes, there arc few seed 
plants which are parasitic on living plants These 
parasites could be entirely or partially dependent on 
their host, affecting either roots or stems. Within the 
last two years, there have been a number of enquiries at 
the East African Herbarium on the identity and methods 
of controlling the parasite Infecting ornamentals and 
seedlings in nurseries. Moreover, observations made in 
Nairobi reveal that hedges, especially planted with 
Bougainvillaea sp . at Jeevanjee Gardens and oilier sites 
are infected The parasite has been identified as dodder. 
Cuscuta camphestris Yuncker, a member of die sweet 
potato family (Convolvulaccac) Discussed here arc 
diagnostic characters, the biology, and methods of 
eradication of ihc parasite. 
Cuscuta (Dodder, Love-vine. Armarbel) is a genus 
consisting of eight species in East Africa, parasitic on 
both wild and cultivated species (Verdcourt. 1963; 
Agnew & Agnew. 1994). These arc non -chlorophyll 
hearing, leafless, twinning plants which altnch their 
yellow, orange, or pink thread-like-stems to the stems 
or other paas of the host. 
The first appearance of the parasite in the field is 
noticed as small masses of branched, thread-like, 
leafless stems which are devoid of the green pigment 
and twine around the stem or leaves of the host. The 
leaves are represented by minute funtionlcss scales 
which arc evident on close examination When the stems 
come in contact with the host, minute root-like organs, 
the haustoria, penetrate into the host cortex and serve 
as an anchor as well as organs of food absorption. When 
the relation widi the host is firmly established the dodder 
plant has no connection with the soil 
Die tiny greenish yellow flowers occur in clusters. 
The fruit is a capsule producing liny grey or reddish 
brown seeds A single plant may produce as many as 
3. IKK) seeds The seeds germinate just like the seeds of 
other plants. Usually their germination occurs a few 
days after the germination of host plant seeds in the 
field. The young seedling of the parasite is a slender, 
yellowish, unbranchcd thread The top end Is raised 
into a more or less vertical position and the growing tip 
moves in a circle in search of a suitable host When a 
support is reached the young stem begins io twin around 
it If the support is a dead piece of wood or non host 
plant, the parasite stem soon dies. On a susceptible 
host the stem of dodder soon produces liaustoria to 
establish itself The lower part then dies and the stem 
becomes free from soil. 
The dodder perpetuates through seeds whtch fall 
on the ground and remain dormant until a favourable 
season returns, ftmions of the stem arc also resistant 
