We've had platypus on our property for the 30 years that we've lived at Running Creek (17km southeast of Rathdowney), until the big flood of early 2008 that demolished 5 bridges and took about 96% of the trees along the riparian strip, uprooting them and probably demolishing platypus burrows.
Since the worst of it happened in the middle of the night, we can only hope the platypus were out feeding and were swept downstream, rather than crushed underground.
After a lengthy spell without them we now have 3 of them in our home stretch of creek again - presumably a mated pair and their young from the recent breeding season.
I saw a swirl in a little farm dam this morning and thinking it might be a duck went for a closer look, but it was a platypus.