 At the time that the Whaleback shell midden was most heavily populated, it could have been sustaining year-round populations of people.This leads into the question of why the site was occupied so much later than other portions of the river, a question which can be answered by looking at the regional-level geology and sea-level rise.The Damariscotta middens are notable for their size and the large presence of oysters in the midden, despite there being incredibly low current populations of oysters.