What Are These Large Nests In North Dakota Trees?

What kind of critters are making these nests you see all across North Dakota? (PHOTOS)

Related Keywords

Mandan ,North Dakota ,United States ,American ,Jill Jaracz ,Census Bureau ,Eastern Grey Squirrel ,American Red Squirrel ,Fox Squirrel ,Bismarck Mandan ,Northern Flying Squirrel ,Red River Valley ,Cottonwood Park ,Burleigh Road ,Tree Squirrels We Have In North ,Rocket Homes ,News ,