Possible Clues:

• Mistake if Ireland abandons this African native
• Animal has good fair treatment and fine housing
• Beast topped tree in clumsy act
• Tall animal's error crossing one river
• African native bloomer on the banks of one river
• African animal, howler gobbling bird with wings pulled off
• One with US military service, fine East African native
• Blunder catching Irish animal, tall
• Mammal whose closest living relative is the okapi
• In US, regular service going by 'iron horse'? No, something bigger