Three former crop fields now part of the Detroit River International Wildlife Refuge and totaling 117 acres in Berlin and Frenchtown townships of Monroe County, are hosting the return of two bird species — dickcissel and eastern meadowlark. These two birds were commonly seen on most Monroe County fence posts just a century ago.
Modern nesting records are sparse in southeast Michigan and there are no contemporary records in the vicinity since the first Michigan breeding bird atlas was published just over 30 years ago.
The nearly complete disappearance of grassland birds in southeast Michigan, including once well-known species like bobwhite quail, bobolink, field sparrow, ring-necked pheasant and many others, reflected the mid-20th-century conversion of hayfields and pasture to soybeans, corn, and winter wheat using techniques relying on herbicide application.
This finding is significant for the Refuge in that these fields were purchased from willing sellers as soybean fields that did not support Refuge priority species. The fields have since been allowed to fallow naturally or with minimal intervention, including wintertime seeding of native plants appropriate to the field’s soil and drainage conditions.
Biological surveys indicate that at least three pairs of dickcissels and one eastern meadowlark are now nesting in these fields just two years since the most recent was actively farmed.
“The presence of these birds represent more than just weedy conservation land along Lake Erie, they are indicators of land that is working for local residents and all those concerned with environmental protection and conservation of Lake Erie,” Refuge Biologist Greg Norwood said. “These restored habitats hold floodwaters, processing excess fertilizer and pollution, and sustain fruit crop pollinators and crop pests.”
Much like the recent return and dramatic increase in bald eagles, osprey, lake sturgeon, lake whitefish, peregrine falcons, and mayflies indicate improvements in the Detroit River, these birds indicate balance in local land use.
“One could not throw a fishing lure into the lower Swan Creek in June 2016 due to the mat of algae and excess plant growth on the surface of the water,” said Norwood. “These small refuge units provide wildlife habitat, but they also reduce fertilizer from entering tributaries to Lake Erie. They were wetlands that were drained for farmland and converting those to conservation lands for the Refuge has multiple benefits beyond just wildlife.”