The Historic Exmouth Plaque erected by the Exmouth Society states:
“This was the location of Pratteshide (Pratt’s landing place) from where the ancient ferry to Starcross, with royal concession, operated for many centuries. Nearby stood Douste’s House, built by Roger Douste prior to 1240 AD, where all shipping dues and ferry rents were paid. In the late 19th century, the area became known as Mona Island, named after one of the cottages on the site”.
Mona Island was originally on the shore of the Exe Estuary, but is now quite a distance away following the land reclamation in the early 19th century which evetually created the area occupied by the Colonies.