And you thought holiday traffic was bad.
"This year's migration has just been absolutely epic," said Christmas Island National Park natural resource manager Brendan Tiernan told Reuters.
"The roads have been a seething mass of red crabs. It's caused traffic jams on this small island and people having to get out of their cars and rake them out the way.
The Australian territory is located near the Indonesian Island of Java and has a permanent population of around 2,000, with most of its land comprised of a protected national park.
To make life easier for motorists several bridges have been constructed over a main road that the crabs can climb over, but it can't contain all of them.
The male crabs have already begun to retreat from the shore, while the females will stay behind for another two weeks to lay up to 100,000 eggs each in the ocean before heading home with the hatchlings to follow in about a month.