What did I hit last year in my boat?

Last May I went to my cabin on Savary Island and when I returned from my trip I washed my boat and found this wierd damage. I don't remember hitting anything out there. Any ideas what this could of been?

A picture of my boat after I got back from trip to Savary Island

Online Boating Exam — Get Your Pleasure Craft Operator Card Now!

September 15th, 2009 was the final deadline for all boat operators to have proof of competency to operate any boat with a motor. You now require a Pleasure Craft Operator Card to operate your boat. The Competency of Operators Pleasure Craft Regulations require boat operators to show proof or risk fines of up to $250.

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