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Tag archives for Susquehanna River

The Turtle and the Town: Freshwater Species of the Week

  The northern map turtle (Graptemys geographica) is a relatively large aquatic turtle that is native to North America. It is named for the lines on its shell, which resemble the contour lines on a map. Map turtles show extreme sexual size dimorphism, which means the genders grow to different sizes. Northern male map turtles…