Absolutely! Bring it if it is something you enjoy. There are Lost and Found dispensary locations in the park. It is very humbling to see how consideration and honesty still exist!
I would check Eagle city's local ordinances, there probably isn't a rule against it, but I wouldn't want to find out the hard way. I know for example that in Boise you need a special permit to detect in parks.
Of course, who would stop you?
I imagine you could. No signs posted that I am aware of. Ask a Park Ranger, they are everywhere.
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