Black-throated Blue Warblers nest in surprising numbers in extreme northeastern Minnesota. They like big old birches, aspens or maples above a dense shrub layer with mountain maple, and preferably on a slope [June; Cook County, Minnesota]
![Black-throated Blue Warblers nest in surprising numbers in extreme northeastern Minnesota. They like big old birches, aspens or maples above a dense shrub layer with mountain maple, and preferably on a slope [June; Cook County, Minnesota]](https://photos.smugmug.com/BIRDS/Warblers/Black-throated-Blue-Warbler/i-ZQGRWw8/0/420a6346/S/Black-throated%20Blue%20Warbler%20Cook%20Co%20MN%20IMG_0008840-S.jpg)
![Black-throated Blue Warblers nest in surprising numbers in extreme northeastern Minnesota. They like big old birches, aspens or maples above a dense shrub layer with mountain maple, and preferably on a slope [June; Cook County, Minnesota]](https://photos.smugmug.com/BIRDS/Warblers/Black-throated-Blue-Warbler/i-88Rw2pJ/0/4e6b7cef/S/Black-throated%20Blue%20Warbler%20Cook%20Co%20MN%20IMG_0008841-S.jpg)