There is a good point in a comment there - at the time crocodiles were not expected:
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@thebackwardpointinggodwit8080 1 year ago
To all those people saying how could someone swim in waters with all those crocs around? Well the bit this account misses is that for many years crocs had been hunted to near extinction in that area and right across the north of Australia. Croc attack had become just a distant possibility in the most remote of locations. Then croc hunting was outlawed in the 70s and croc numbers recovered quickly and their distribution moved southwards to include places like the Daintree over the next decade or so. No-one really expected to see big crocs in the Daintree in the early 80s and what these people did was normal and considered not dangerous at the time. I was in Australia at the time and I remember when that attack happened - it didn’t seem possible. I and most people thought it was much more likely that she simply drowned or disappeared - or maybe some foul-play had occurred and people were covering it up - but we were very skeptical that it was a croc. Now crocs are common right across the north of Australia and sadly attacks keep happening, but Beryl Wruck just had the misfortune to be the first person to find out the hard way that things had changed and what everyone considered safe no longer was.
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