It's believed Maasai men, who live on the ranch and are traditionally nomadic herders, are responsible for the lion and hyena deaths. At least one Maasai herder has been arrested in connection with the crimes, according to Paula Kahumbu, head of the Nairobi, Kenya-based conservation group WildlifeDirect.

In southern Kenya months of drought have heightened long-standing tensions between wild predators and Maasai people.

(See "Elephants Fall to Drought in Kenya's Amboseli Park.")

As arid conditions make food and water harder to obtain, livestock become ever more valuable to both their owners—and to neighboring predators.

The poisoning occurred on April 2 at the Olgulului Group Ranch near Amboseli National Park, Kahumbu said.

Kahumbu received the news from the Kenya Wildlife Service, which had