I've been in Kenya for my thesis research in 2009 for three months so my knowledge is not sufficient enough to tackle this one. I was thinking an almost adult Gabar Goshawk (strange with striped rump?) or maybe Ovambo Sparrowhawk?
Since a couple of monhts I am a validator for Observado.org. This is a good tool to fill in your sightings for birds or other fauna or flora. It can be used for ranging species and interesting sightings. It could also promote bird
watching on local en international level since more and more people are using it. The goal of observado.org is to make available sightings of observers all around the world and help with knowledge on biodiversity. Not only citizen scientist, but also professional researchers share their data on this website.
For more info:
Regards,
Wouter Bol