Travellers who want to visit the most ethical zoos can check to see if a particular animal park is a member of the Switzerland-based World Association of Zoos and Aquariums (WAZA).
The family was on tour at the Waza National Park in Cameroon's Far-North Region before they were abducted at gunpoint by five gunmen aboard motorbikes, according to paramilitary sources in the area.
They had been returning from a visit to Waza National Park - which is described as a beautiful landscape, trodden by giraffes, elephants and antelopes - where they had spent the previous night.