Do they take reservations

Yes, but they call it "call ahead". They will require you to arrive 15 minutes prior to the agreed upon time though so it's not truly a "reservation." They also ask everyone upon arrival if they "called ahead."

You must go there in person to reserve. They do not take reservations over the phone.

We always reserve

I would say that while you can "call ahead". The more accurate answer is "No". We've called ahead and not, didn't seem to make any difference.