ecology is relatively high rainfall. Within their areas of dis- 

 tribution, these ticks vary in relative prevalence and density, 

 due in part to approaching thresholds or extremes within the 

 range of tolerance. A very definite line of demarcation, un_ 

 effected by the movement of cattle along trade routes, exists 

 between these two zones. 



Huts of pastoral peoples in which cattle and other domestic 

 animals freqtiently rest harbor the tropical bont tick. Smith 

 (1955) noted its presence in human habitations and a similar 

 situation may have accounted for Robinson's (1912) remarks con- 

 cerning parasitism on children by the so called variety nocens . 



The red- billed oxpecker or tickbird, Buphagus e. erythro- 

 rhynchus (Stanley), which attends all the larger herbivores 

 except the elephant and the hippopotamus, has been shown by 

 Moreau (1933) to be a predator of some importance on A. variegsu 

 t\im and other economically important ticks. Of the 5^ tickbirds 

 examined in Tanganyika, 186 specimens of A. variegatum were found 

 in the stomach contents of sixteen; the number of ticks per stom- 

 ach ranged from one to IO9. 



In Kenya, van Someren (l95l) took specimens of the tropical 

 bont tick from stomachs of a few of the same birds that he ex- 

 amined. He also foxind unidentified ticks in Tanganyika birds, 

 B. a. africanus . van Someren* s interesting biological study of 

 The^red- billed "oxpecker includes observations on the birds* habit 

 of irritating sores on domestic animals. 



Buphagus erythrorhynchus and B. africaiius subspp. range through 

 African savajmahs and frequently are seen clinging to the flanks 

 or legs of domestic and wild animals. Lang {192J+) noted the tick- 

 bird acting as a sentinel for elands. Loveridge (1928) reported 

 specifically unidentified ticks in stomachs of Tangan^-ika tick, 

 birds and Dr. J. P. Chapin foxind ticks in their stomachs in the 

 Congo and in Kenya (Bequaert 1930B). I am told that the best 

 account of tick-eating habits of these birds is quoted in Banner- 

 man's Birds of Tropical West Africa (Volume 6, page IO5). 



Assertions that the white heron, or cattle egret, Bubulcus 

 spp., is a tickivore are not supported by evidence. Dr. Chapin 



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