cicada on the deck

Now I’m confused. Growing up, I remember cicadas chirping every summer. Then somebody told me that I was wrong and that they all come out en masse every 17 years and that I must have just been remembering one summer in particular. I saw this guy on the deck this summer. Last summer I saw one crawling on a sidewalk.

What’s the deal? Are these just advance scouts for the big party next year?

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