As a result of yesterday's high wind, we had an extraordinarily low tide today. The graph below shows the predicted and recorded tide for today at Solomons Island, a few miles south. Today was almost a full foot lower than the predicted astronomical tide. The source of the graph is here, one of my favorite weather sites.
Give up? It's a whale's ear bone. Not as complete as the one at the link, but quite good and very large. Certainly the best I've ever found. Much rarer than sharks teeth; sharks have many teeth through their lives; whales have only two ears each.