What motivated the British Government to issue permit to Massai herders?

What motivated the British Government to issue permit to Massai herders? Describe the sudden change in the lives of pastoralist?

The Massai pastoralist had dominated agricultural and pastureland in the pre-colonial era. In 1885, Massailand was cut into half with an international boundary between British Kenya and German Tanganyika. The best grazing lands were gradually taken by the Britishers and the Massai were pushed into a small area. The British colonisers encouraged the local peasants to expand cultivation. They thought pasturelands as wastelands and unproductive. The colonisers also saw pastoralists as dangerous and savage. From the late nineteenth century they began imposing various restrictions on them.
So they issued permit to Massai herders and the police were given instructions to keep watch on their movements.
The permit system affected the lives of pastoralist in following ways
(i) Grazing land reduced and feeding cattle became very difficult.
(ii) Underfed catde died which had negative impact on livelihood of Massai herders.
(iii) They also lost valuable water resources for themselves and their catde.
(iv) They were sometimes imprisoned without valid reasons.
(v) Restriction on their movement or entry to white areas not only affected their freedom of movement, but also their livelihood.
(vi) Maasai herders were expected to confine within semi-arid drought-prone area and frequent drought reduced the size of their cattle.