Dubbed the "Last Retreat of the Roan Antelope", the park protects the only indigenous population of rare roan antelopes within Kenya.

[1] The park was established in 1966 as Lambwe Valley Game Reserve.

It was later renamed “Ruma” after one of Kenya's most powerful wizard, the much feared Gor Mahia who lived around the park (affiliated to Gor Mahia F.C.).

Game species range from African leopards (Panthera pardus pardus), roan antelopes (Hippotragus equinus), eastern black rhinoceros (Diceros bicornis michaeli), Rothschild's giraffes (Giraffa camelopardalis rothschildi), oribis (Ourebia ourebi), cape buffalos, Lelwel hartebeests (Alcelaphus buselaphus lelwel), olive baboons, Bohor reedbucks (Redunca redunca), hyenas, servals (Leptailurus serval), topis (Damaliscus korrigum), honey badgers (Mellivora capensis), bushpigs (Potamochoerus larvatus) and vervet monkeys among others.

The rare intra-African migrant, the blue swallow (Hirundo atrocaerulea) is one such avian species.