The Pitt-Addington Marsh WMA (Wildlife Management Area) supports over 200 bird and 29 mammal species. This WMA is generally a flat, alluvial floodplain made up of dyked and undyked areas.

Pitt Lake is the largest tidal freshwater lake in the world. There is a rare reverse delta at the mouth of the Pitt River, a result of deposition which occurs when rapidly flooding tides dam and reverse the main Fraser River outflow back up into Pitt Lake. The WMA also contains Pitt Polder Ecological Reserve, an area of sedge bog and two forested granitic outcrops rising 114 metres above the floodplain.

Parts of the WMA accommodate wildlife viewing and limited seasonal hunting.