Karura Forest #42: Clever Corvids
The cache, a small camo-pot, is hidden under bark pieces and leaves at the foot of the streamside giant near the start of the Turaco Path near Junction 8 with the main Family Trail on the southern edge of the Forest.
To access the cache:
From main gate A (Limuru Rd) @ S01 14.829 E36 48.948, after paying your entry and parking fees, proceed the 1.2km or so to the junction by the barrier at S01 14.447 E36 49.148. Turn right here, continue past the new River Cafe to the extensive Amani Garden parking area @ S01 14.5777 E36 49.235. From here take the exit gate at S01 14.594 E36 49.191 which gives access to a small trail crossing an open grassy area to join the Lake Trail heading east from Junction 5. Turn left (east) and follow this trail to the cache location.
See GC6EG59 Karura Forest #40: Graceful Scavenger for waypoints.
For background information on Karura Forest including access, fees, opening times, features, a detailed trail map and useful links, see GC4PD3V Karura Forest #1: Intro, Info & Entry.
Corvids are members of Corvidae - a cosmopolitan family of oscine passerine (pearching) birds that includes crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs, and nutcrackers. They are commonly known as the crow family and over 120 species are described.
They are thought to be the most intelligent of the birds, and among the most intelligent of all animals, having demonstrated 
self-awareness in mirror tests (European magpies) and tool-making ability (crows, rooks) - skills until recently regarded as solely the province of humans and a few other higher mammals. Their total brain-to-body mass ratio is equal to that of great apes and cetaceans, and only slightly lower than in humans. See here for more fascinating info on these clever birds.
The local representative of the family and a bird you are likely to see in and around Karura Forest - and indeed many other parts of Africa - is the Pied Crow (Corvus albus). This species, Africa's most widespread member of the genus Corvus, occurs widely throughout sub-Saharan Africa (see distribution map in Gallery). It inhabits mainly open country with villages and towns nearby. It does not occur in the equatorial rainforest region. It is rarely seen very far from human habitation, though it is not as tied to the urban way of life as the house crow (Corvus splendens) of Asia, and may be encountered far from human habitation.
Pied crows are usually founds in pairs or small groups, although plentiful food may attract large flocks. They behave in a similar manner to the hooded and carrion crows, mobbing certain birds of prey - such as yellow-billed kites. Its call is a loud harsh 'kraah' and it also has a snoring 'khrrr' - listen to the calls here.
It is an omnivorous bird which obtains all of its food from the ground. It eats mainly plant material such as seeds, grain, nuts, fruits, neactar and roots, but it also eats insects, small invertebrates (like termites), small reptiles like lizards, small mammals, bats, snakes, young birds and eggs, fish, carrion and any scraps of human food. It is often seen in large numbers scavenging around slaughterhouses.
It is monogamous. The nest - a large bowl of twigs - is usually built in an isolated tree, or on a telephone pole, pylon, windmill or occasionally a building. Both sexes build the nest and 3–6 eggs are laid from September to November, which are normally covered when the incubating female leaves the nest. Incubation takes 18–19 days and the young are usually fledged by around 45 days with both sexes helping to rear the young.
Video links: see here (strange noises), here (crows protecting nest from vervet monkey), and here (barking) for short videos on pied crows; see also here (corvid intelligence) and here (excellent and fascinating full length documentary on the 'Secret Life of Crows').