Greater Rondeau Area

Site description (2001 baseline):

Site location and context
The Greater Rondeau Area is situated on the shoreline of Lake Erie, southeast of the town of Chatham. In addition to Rondeau Provincial Park, this site encompasses adjacent areas including Rondeau Bay and associated marshes and adjacent fields, Bates marsh, Erieau pier, harbour and beach, McGeachy's Pond, and the Morpeth Cliffs. Rondeau is the largest provincial park in southwestern Ontario. It is a low-lying sand spit that consists of a series of ridges and sloughs. A variety of habitats are present which contribute to the bird diversity. These habitats include productive southern hardwood forests, sandy beaches and wetlands ranging from woodland sloughs, to a large marsh and productive inland bay. The unique habitats of the park and surrounding area support many nationally vulnerable, threatened, and endangered species of flora and fauna.

Key biodiversity
The Greater Rondeau Area supports significant populations of migrating waterfowl and shorebirds, along with populations of several threatened species that nest in the area.

The wetlands of Rondeau are recognized as a major waterfowl staging area. In addition, shorebirds are also found in large numbers. Species that are present in significant numbers (greater than 1% of their estimated North American or world population) include: Greater Scaup (1.6%); Tundra Swan (4% of their North American population); Common Goldeneye (about 1%); Ruddy Turnstone (1.2%); and Forsters Tern (about 1%). In spring and fall, thousands of Black-bellied Plovers and American Golden-Plovers can be seen feeding in open fields; the exact composition of these flocks, and therefore their significance, is not known, however. Up to 250 Whimbrel have also been recorded in spring migration.

Numerous nationally endangered species nest at Rondeau Provincial Park. The park has traditionally supported the largest breeding population of Prothonotary Warblers in Canada. This species has since declined in numbers, with only 13 pairs being recorded in Canada during 1997, six of which nested at Rondeau. Acadian Flycatchers and King Rails also breed at Rondeau: in 1997, four territorial Acadian Flycatchers were recorded in the mature deciduous forest habitats, and in the adjacent marsh, two King Rails were recorded. For both of these species, the estimated Canadian population is well below 100 pairs. In addition, at least nine pairs of Least Bitterns (nationally vulnerable) were recorded in 1997.

During the 1981 to 1985 surveys for the Atlas of the Breeding Birds of Ontario, the Rondeau area had the highest diversity of breeding birds in the province. Out of the more than 330 species recorded as breeding in Ontario, 134 were recorded in the Greater Rondeau Area.

Conservation responses/actions for key biodiversity
Rondeau was designated as a provincial park in 1894. Despite this legislated level of protection, there are still threats to the habitats and wildlife of this area. Natural processes of habitat succession in the forested area, and soil erosion from the adjacent agricultural areas are altering the structure of the ecosystem. Introduced invasive plants such as Phragmites are increasing in numbers and out-competing the native plants. The excessive use of herbicides and pesticides on nearby agricultural fields could also impact wildlife.

Recommended citation
BirdLife International (2023) Important Bird Area factsheet: Greater Rondeau Area. Downloaded from on 09/12/2023.