For years, farmers in Kenya's arid north have suffered huge losses when droughts wiped out their cattle herds. Now, they have a means to protect their sole source of livelihood when rains fail and grasslands disappear. A new insurance scheme hopes to safeguard cattle-rearers in northern Kenya's drought-prone Marsabit district by using satellite imagery to track changing landscapes and the subsequent loss of cattle. The program, launched by the International Livestock Research Institute, is being billed as the world's first insurance program to track changing pastoral grounds. When the satellite photos reveal that a verdant green landscape has changed to a dry brown, the insurance kicks in and farmers can collect their payments. The program will make things easier for insurance companies--for whom estimating losses in the past has been all but impossible.Partly because it has simply been too expensive for insurers to go and count the number of dead animals which might be spread over a vast rural area