Natural heritage features at the mouth of the Don River.
Details of Site Location: Along the original shoreline of the 1790s on the mainland, above the isthmus and Ashbridge’s Bay, at the mouths of the Don River.
Boundary History: The area is an irregular shape occupying possibly 40 acres.
Current Use of Property: Industrial and commercial establishments, and roads to service them.
Historical Description: Depending upon the purpose of the surveyor or mapmaker, the early records of the area vary. In the Aitken map of 1795, the mouth of the Don is drawn with two islands, one above the other and both surrounded from some distance away with river routes. In Aitken’s map the upper island is the smaller of the two and almost east–west in orientation; the larger island is shown with a fairly regular north shore and a ragged, irregular south shore. The river flows around in roughly three routes. In the Bonnycastle map of 1833, Kingston Road crosses below some tight meanders in the river, which flows through slower curves to where the original shoreline is masked by “deep ponds” and areas “full of creeks” east of the isthmus. Here a clearly marked river route wanders with two flows: into the harbour through the isthmus, and deep into Ashbridge’s Bay. In all maps up to the 1860s, the area is shown as full of rushes, weeds, and swampy growths. Bonnycastle remarks on the “deep swamp full of intricate channels and extensive ponds.” From Mrs. Simcoe onwards, every written account remarks on the swamp and abundant wildlife, both marine and land‑based. It is now known that Governor Simcoe and others suffered from “lake fever” – malaria contracted from mosquitoes in the Don marshes. The swamps of the Don mouth were fish‑spawning grounds, and when the swamps and Ashbridge’s Bay were destroyed, the commercial fishery that was dependent upon them also disappeared. More maps and technical studies, proposals for redevelopment, petitions and pleas for restoration, and Parks planning have been produced on this area than on any other part of the Toronto shoreline, including Scarborough Bluffs. The last proposals for partial restoration and parks use were made in 1912 and abandoned after 1914. The maps of that period, made after the channeling of the river and redirection of its flow, show no islands, a reorganized isthmus, some open water in Ashbridge’s Bay, and fairly extensive marshlands in part of the area south of the line of the mainland.
Reference Sources: Richard Bonnycastle, No. 1 Plan of the Town and Harbour of York, Upper Canada (1833); Alexander Aitken, Survey of the River Don (1788); Francis Magnuson and Regier Talhelm, editors, Rehabilitating Great Lakes Ecosystems (Great Lakes Fishery Commission, 1979).
Acknowledgements: Toronto Field Naturalists; Maps Project collections.