The completion of the famous Lunatic Line, as the Kenya - Uganda railway was then known, opened up the area around Nairobi to human settlement, further restricting the free movement of the animals.
Rampungnya Lunatic Line yang terkenal, sebutan bagi jalur kereta api Kenya - Uganda pada waktu itu, membuka daerah sekitar Nairobi untuk dihuni manusia, sehingga kian membatasi ruang gerak binatang.