That rock looks like the Creation Turtle.
``Beneath the Tree was a great hole. The woman peered from the edge into the hole and suddenly fell off the edge. As she was falling she grasped at the edge and clutched in her hand some of the earth from the Sky World. As she fell, the birds of the world below were disturbed and alerted to her distress. The birds responded and gathered a great many of their kind to break her fall and cradle her to the back of a great sea turtle. The creatures of the water believed that she needed land to live on, so they set about to collect some for her. They dove to the great depths of the world's oceans to gather earth to make her a place to live. Many of the animals tried to gather the earth from the ocean floor, only the muskrat was successful. With only a small bit of earth brought onto turtle's back from his small paws, Turtle Island began to grow.
The Sky Woman soon gave birth to a daughter on Turtle Island. The daughter grew fast. There were no man-beings on Turtle Island, but a being known as the West Wind married the daughter of Sky Woman.``
http://www.firstpeople.us/FP-Html-Legends/TheCreationStory-Iroquois.html