Forget about kangaroo. It is even more silly if you think that the wombat or kola bear could travel from Mt Ararat to Australia. These 2 creatures are not known for travelling over great distance.
How the Spectacled Bear got back home to South America is another conundrum.
Good luck all these animals finding food for their respective trips home with everything destroed by the flood. In fact that they would not have had enough food on the Ark for the over half a year trip to begin with .. Elephants can eat up to 650 lbs of food a day (cut this in half, rations and call it 300 lbs) 2 Elephants = 600 lbs x 150 days = 90,000 lbs of food.
For an Elephant of weight = 10,000 lbs .. this would be 9 x the volume of an Elephant in food .. but wait .. an Elephant is a vegitarian and hay and grass have far more volume than meat and bone.
Put in at least a 3 times volume multiplier and you would need the equivalent of 27 Elephant volumes just for the Food.
The size of a ship needed to care for just two elephants for 150 days is really really big.
Of course all this calculation is a mute point because there is no way for all these animals to have made it to the Ark to begin with.
In Noah's time, assuming it were possible, it would take a number of years for he and his sons to collect just two Polar Bear and bring them back to the Ark.
Considering the "great flood" happened roughly 2200-2400 BC. Noah and son's would still be collecting specimens required to have 2 of each of the distinct species found on the planet today.
