Another 107 ha (260 acres) are owned by the Government of Canada, including the "most critical sites used by the large roosting flocks of shorebirds during high tide".

This site exhibits "the world's highest known density of the crustaceans Corophium volutator",[7] up to 60,000 per square metre during their reproductive cycle,[2][6] which supports large populations of migratory shorebirds.

[7] These double their weight to 40 g (1.4 oz)[5] before continuing their migration by flying to the North Atlantic, which winds carry them to the northern coast of South America in two to four days.

[8]: p 44–47  An important associate of the quarry, at one time called the Albert Freestone Company, was George Lang, a builder responsible for several notable Halifax structures using Mary's Point stone.

The quarry was opened for the last time in 1987 to provide stone used in the restoration of the former Dominion Building in Halifax, now the Art Gallery of Nova Scotia.