Deon Warnick’s three chest freezers stood silently in his living room, lids open. Without any fish to keep frozen, he was using them as cupboard space instead. In his backyard stood a stack of empty ...

Moller, the owner of Mogi’s hiking trail, said the salvinia have clogged up and damaged boat engines and also hurt fishing communities over the nine years that he has lived in the area. South Africa’s ...