Johnny Rodrigues of the Zimbabwe Conservation Task Force blamed a spate of wild animal killings on poaching. "Usually you hardly hear of anything like this, but these animals are being traumatised," he said.
Peter Evershed was on a fishing trip in the remote Mana Pools area with three people, including his brother-in-law, when he was attacked. "These fishing camps don't have security fences, but that's why people go there - and you go there at your own risk because it's a wildlife area and they're trying to keep it as natural as possible," Mr Rodrigues said.
Eight villagers were attacked by lions earlier in the year - but 200km to 300km (125 to 185 miles) further down the river, he said. Last month, a South African tourist was killed by an elephant who attacked him as he approached a houseboat on Lake Kariba.