They recommend reservations if you want to go out on one of their tours. If you want to just rent a kayak or paddleboard to take out on your own reservations are not required. The equipment is rented on a first come, first serve basis. Their website outlines their policies pretty well.
Best to make a reservation... my wife & I called the day of & they were booked, but they were so accommodating they made another spot for us. Hope this helps.
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