Watching the Current
Mike was watching the fast rip current that developed between Fort DeSoto's North Beach and Shell Key (in the distance). The changing tides create very fast currents here that can be dangerous. If you look closely at the large version of the photo, right along shore is sand colored water that is moving way faster than I can run. It reminded me of rapids in a river.
We dropped some palm fronds into the water and watched as they floated toward the Gulf, got sucked under by two whirlpools, and surfaced about 30 seconds later several yards out in the Gulf of Mexico.
I think it was a good demonstration for the boys. Whenever we go to the beach in Florida or Lake Michigan, I look for rip tides and show them the signs and indicators so they will be aware of the dangers. I also quiz them every time - if they're caught in a rip current, the way to get out is to swim parallel to the beach until they're out of the current, then swim back to shore.
In this unusual case, they would have to swim toward the sand where Mike is standing until they were out in the Gulf, then they would need to swim parallel to the beach.
They all got it right!