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Penning, W.L., and F.J. Cuthbert. 1990. St. Louis River Estuary Colonial Bird Program Final report submitted to the Nongame Wildlife Program, Minnesota Department of Natural Resources. 23 pp.


This is the eighth in a series of annual reports on the St. Louis River Estuary Colonial Bird Program. The purpose of this program is to provide safe and secure long term nesting areas for Common Terns (Sterna hirundo) and Piping Plovers (Charadrius melodus) in the St. Louis River estuary and to establish breeding populations of terns and plovers that are self-sustaining. This program was implemented by the Minnesota Department of Natural Resources (MDNR) and the Wisconsin Department of Natural Resources (WDNR); it is a cooperative project between the two states, as well as with other government agencies and private groups.

The Piping Plover is Endangered in both states as well as federally. The Common Tern is listed as a species of Special Concern in Minnesota, Endangered in Wisconsin, and a species of Special Emphasis by the U.S. Fish and Wildlife Service.

It is assumed that the reader is somewhat familiar with this program; therefore, this report only briefly references the background and history of the program. For more detailed information see earlier reports (Davis 1980, 1982-1987; Penning 1988, 1990). In 1983 a program to monitor population trends of Piping Plovers, Common Terns, and Ring-billed Gulls (Larus delawarensis) was implemented. For data on these species in the estuary prior to 1983 refer to Davis 1983. A tern relocation program was formulated in 1978 (Metropolitan Interstate Committee 1978). By 1981 habitat management began on Barkers Island with the clearing of 8 acres. In 1983 13 acres were cleared on Herding Island. In 1989 active attraction of terns and plovers to Herding Island was discontinued due to repeated problems with predators and local residents. Habitat management began on Interstate Island in 1984 and has continued to present. All live and dead vegetation was removed in 1989 and portions of the island were rip-rapped to prevent erosion. Herbicides were applied to the center of the island in 1990 to control vegetative growth. In 1987 an eight acre portion of Wisconsin Point was acquired; Barkers Island was dropped from the management program due to failure of terns and plovers to use the island.

Another focus of the program has included activities to discourage the use of highly disturbed sites and encourage use of prepared sites by Common Terns. Tern decoys and sound systems with recorded tern vocalizations were placed at each management site beginning in 1983 (Herding and Barkers Islands), and at Interstate Island in 1985 and Wisconsin Point in 1987. Intensive discouragement activities at highly disturbed sites began in 1985.

The 1990 program included all of the traditional management areas in the St. Louis River Estuary and the Ashland Pier site in Ashland, Wisconsin. Plans to continue work in the Shipwreck Islands, Lake Kabetogama, St. Louis County, MN, were discontinued when the terns failed to return in 1990. An intensive Ring-billed Gull control program was initiated at Interstate Island in an attempt to prevent the invasion of gulls into the tern management area.

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