Actually I saw the person after I saw the thing. The thing in this case was a mole who seemed to have decided that he needed some exercise.
Then I saw the person, my husband, trying to get the mole out of the pool.
Not the happiest camper, considering he had just finished cleaning the pool. But he managed to get the mole out using the long handled leaf skimmer.
The mole is back in the yard digging a volcanoes and eating grubs.