Referring to an email of a couple of weeks ago re some odd birds seen around 
Nbi... there's some great and interesting birding going on!!  

> Young Brown-chested Alethe, Karura Forest, 9 April 2003.  James Kiptoo first
> noted a bird on the forest floor that appeared "brown with some streaking
> below".  Five of us searched for it, and found the small robin-type bird perched
> on a branch just over the ground.  It seemed to be covered with pale spots, and
> we called it an immature White-starred Robin.  However, when Johanna studied the
> bird books, she realized that the browner overall tone of this bird made it more
> likely to be an immature Brown-chested Alethe. Both the alethe and the robin are
> found in the forest, but the sighting was on a dry slope where we normally see
> the alethe.

The best way to tell the difference is probably on the shape and size of the 
bird as the forest robin is a smaller more delicate bird, esp the head and bill 
than the alethe. Alethes tend to be stronger and heavier in build generally, I 
believe, with shorter tails (hence the same body length as the forest robin in 
the field guides) but bulkier bodies and legs. Colour is always a potentially 
dangerous feature to base an i.d. on esp as lighting can affect it as can age, 
wear of feathers, moult, etc..etc.. Having said that, even young forest robins 
tend to be yellow in hue rather than a more rufous brown of young alethes. 
> 
> Mystery Cuckoo at Paradise Lost, 16 April 2003.  A morning with scattered
> showers and surprising birds.  A grey bird with drooping wings was first
> spotted perched on a fencepost near the riverine trees above the waterfall. Was
> it a bird of prey, a dove, a cuckoo?  It was grey all over, paler below, no
> obvious yellow anywhere.  The large wings were open and drooping, hiding part of
> the fencepost.  Some observers thought they saw faint barring below. The bird
> flew and landed low in a large tree.  From that angle we could see pale
> underparts and a very large, rounded, blackish tail.  Then the bird disappeared.
> 
Again.. hard to tell exactly what this is... overall shape and relative shape 
of wings / tail / head are very useful features to look at especially for 
i.d.'ing the family of a bird first.

Sorry not to be able to help much more than that..

Colin