The western corridor road, which branches left from the Seronera-Banagi road 5 kms from Seronera, eventually takes you to the Park's Ndabaka gate, near the shores of Lake Victoria, and is the route to Musoma and Mwanza. As you travel westward you will have the Grumeti River, which drains into Lake Victoria, to your right. Ahead of you and to the left is the central range of hills; 30 kms short of Ndabaka you cross extensive black clay plains. This soil, known as 'black cotton' becomes waterlogged during the rains. During and just after the wet season you will see large numbers of beautiful yellow and blue hibiscus plants flowering above the surrounding grass cover. Whereas the short-grass plains are at their best during the rainy season, the western corridor is more interesting during the dry months of June to October, when in any case, traveling is easier.
Patterson's Eland is a large rather cow-like antelope weighing as much as 900 kgs and measuring nearly two meters to the top of the hump. In color the females are reddish-fawn and the males are grey. Both sexes have lateral stripes around the barrel of the body and a conspicuous tuft of dark hair on the dewlap.
Both males and females have heavily spiraled or corkscrew horns that grow straight back from the head. Eland, like cattle, are very susceptible to rinderpest, a disease of livestock, and were nearly wiped out at the turn of the century when a severe epidemic struck East Africa. In ranching areas, where some wildlife has been allowed to remain, eland have been known to mingle with cattle and even allow themselves to be herded into a stockade at night.
The Candelabra Tree grows profusely in the Ndabaka area, as it does in many parts of the park, including Seronera. It often gains a foothold in the crevices of a kopje where its dark green, succulent leaves contrast with the grey of the rocks. Also growing here, though less common, is the toothbrush bush, the stems of which when chewed at the ends make a very serviceable toothbrush. If you are interested in seeing it, ask your guide to point it out and show you its use. Wait-a-bit thorn grows along the corridor road. In March the white flowers, which have a very sweet smell, can be seen decorating the landscape.
Known to nest in tall trees in the Mbalageti valley are Martial Eagles, another of the great birds of prey of the Serengeti, being second in size only to the crowned eagle. This bird, ashy brown above and on the wings, has a distinctive white belly dotted with brownish spots. Martial eagles are powerful hunters, able to kill game birds, hyraxes and small antelope.
To the south-west of the western corridor lies the Ndoha Plain—this area is at present rather inaccessible. It is here that you might see Roan Antelope. These striking animals are rust grey and have prominent black and white facial markings, long ears and strong heavily ridged, backward sweeping horns. This area is also the main breeding ground in the Park for topi.
Baboons and vervet monkey troops are commonly found in the western corridor and in the riverine forest bordering the Grumeti River. Black and White Colobus monkeys are also to be seen leaping from branch to branch with an almost flying action. They are largely arboreal, feeding on the leaves of the trees in which they live. They can be detected as the troop moves rather noisily through the branches overhead, making fantastic leaps from tree to tree. The best place to see colobus is where the river comes close to the road at the north end of Kimarishi Hill.
An adult black and white colobus measures around 80 cms from the head to the base of the tail, while the tail itself is about another 100 cms long. Colobus live in family troops with an adult male and several females. Young males leave and either form new troops or are solitary.
In the river itself are some exceptionally large Crocodiles. These great reptiles can be watched as they bask on the sandbanks of the river, but do not venture too near the waters' edge as crocodiles seize prey with surprising speed. Once caught in the vice-like jaws, the prey is drawn under water to subdue it and either torn apart immediately or stored until wanted.