This is a report on the mammals found in April 2001 during a brief terrestial vertebrate fauna survey on previously unsurveyed Croker Island which is 3 km offshore from the Cobourg Peninusula. Seven mammals were recorded but only 3 were native. These were black flying -fox (Pteropus alecto), grassland melomys (Melomys burtoni) and the dingo (Canis lupus dingo). The remaining 4 species were domestic and feral animals (horse, cat, cattle and pig).