These data are spatial estimates of fractional wetland area and were used to quantify wetland area change in the Davis Pond and Caernarvon Freshwater Diversion outfall areas during a 1984–2019 observation period. Trends in wetland area through time were fit using a penalized regression smooth spline. The trends are therefore generalized in time and are intended to present coarse spatial and temporal scale observations of trends in wetland area change.