Godwino (sorry if that is a wrong name), no of course I don't want the
critter to starve ! I do feel a serious responsibility for all the
creatures in my garden (some people close to me recommend counselling LOL),
and I would not want it hurt in any way.

But is it possible he found a food source anyway ? Quite a few bugs in the
pond, and places where the bigger koi can't come.

Despite the smiley, I'm serious about "wondering what to do".

A bit more info: I believe it is a "Missisipi Roadmap" turtle (very liberal
translation from Dutch), and they are quite shy. The read eared slider and
his yellow friend have learned to swim towards me when I'm there with food
(or without...) but the two smaller ones just panic and try to hide where
ever they can. Maybe it didn't feel it could hide well enough and feels
safer in the bigger pond (including the area under the deck) ?

Theo

Return the runaway Turtle back to where he is supposed to be. You
wouldn't
want him to starve to death would you?