The Minneapolis Chain of Lakes/Theodore Wirth Park IBA includes the five lakes which comprise the Minneapolis' Chain of Lakes; Cedar Lake (173 acres), Lake of the Isles (118 a), Lake Calhoun (422 a), Lake Harriet (343 a) and Brownie Lake, the Thomas Robert?s Bird Sanctuary and Lakeview Cemetery, along with Theodore Wirth Park including the Eloise Butler Wildflower Garden and Bird Sanctuary, the Quaking Bog, Birch Pond, Wirth Lake, the Basset?s Creek pools and the JD Rivers? Children?s Garden. The area is approximately 1-3 miles west and southwest of downtown Minneapolis, most of the land is owned and managed by the Minneapolis Parks and Recreation Board and surrounded primarily by residential neighborhoods.
A total of 263 species of birds have been recorded within the IBA, including 72 species of Conservation Concern. This reflects both its importance as an oasis of bird habitat in the larger urban area as well as its popularity with Metro birders. From 1977-2005, Steve Carlson collected data on species utilizing the four lakes and adjacent lands. His data breaks down the birds seen by location as follows: Cedar Lake: 209 species, Lake of the Isles: 158 species, Lake Calhoun: 190 species, Lake Harriet: 112 species, Robert's Sanctuary: 197 species, Lakewood Cemetery: 173 species
A black-crowned night heron waterbird colony occurred on the south island in Lake of the Isles from 1981 through 1990. Four green heron nests, 7 great egret nests and 146 black-crowned night heron nests, all in green ash trees, were found in 1981. A high count of 170 total nests was made in 1986. During several of those years, yellow-crowned night herons were observed in the area by both Steve Carlson and myself. The colony was abandoned in 1991. Although waterbird colonies have occasionally become active again after abandonment, it is unknown whether this will happen in such a highly developed urban setting.