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Lane, W.H., M.S. Martell, and P.T. Redig. 1986. Winter activity of bald eagles (Haliaeetus leucocephalus) at Pigs Eye Island #1, on the Mississippi River. Final report submitted to the Nongame Wildlife Program, Minnesota Department of Natural Resources. 7 pp.


The Mississippi River corridor, an area extending from the Twin Cities into the Southern United States has traditionally supported large numbers of wintering Bald Eagles (Haliaeetus leucocephalus). The eagles are attracted to open river water and a resulting concentration of potential prey species (waterfowl, fish, small mammals). The river and its tributary systems provide food and shelter for wintering eagles from November through late March.

During a study made from 21 December 1985, through 21 January 1986, the area surrounding Pigs Eye Island #1 was identified as significant bald eagle wintering habitat. Located 2 miles southeast of downtown St. Paul on the Mississippi River, Pigs Eye Island #1, and the smaller island to its immediate north (henceforth called Island #2), are situated near the eastern shoreline directly west of the Metropolitan Waste Control treatment facility.

In response to concerns expressed by the Minnesota Nongame Wildlife Program and the Pigs Eye Tree Top Coalition, this study was undertaken to:

  1. Identify daytime and evening habitat for bald eagles on or near Pigs Eye Islands 1 and 2.
  2. Assess the possible impact of tree removal on Islands 1 and 2 on wintering eagle populations.

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