Northern Prairie Wildlife Research Center
Avian use of loosestrife is not well studied (Thompson et al. 1987). Prince and Flegel (1995) found no records in the literature of loosestrife as avian food or nesting habitat in Lake Huron wetlands. In New York wetlands, Rawinski and Malecki (1984) observed that Marsh Wrens (Cistothorus palustris) preferred cattail for nesting, whereas Red-winged Blackbirds (Agelaius phoeniceus) preferred loosestrife for nesting. Rawinski and Malecki (1984) also noted that Black-crowned Night-herons (Nycticorax nycticorax) roosted in loosestrife and Pied-billed Grebes (Podilymbus podiceps) nested in one- and two-year-old emergent loosestrife stands. Kiviat (1996) found 15 American Goldfinch (Carduelis tristis) nests in loosestrife during a 23-year study of birds in the Hudson Valley. Swift and co-workers (1988) observed Least Bitterns (Ixobrychus exilis) and other birds in Hudson River wetlands that consisted of cattail, river bulrush (Scirpus fluviatilis), loosestrife, and common reed (Phragmites australis).
Minnesota established the first statewide loosestrife control program in 1987 with the goal of broadening public awareness, conducting inventories, developing control methods, and initiating control work (Skinner et al. 1994). Minnesota has spent $US 1.75 million since the beginning of the program (Skinner, pers. comm.). Other state and federal agencies also have spent considerable money and effort to control loosestrife, in part, because wildlife values of this plant are widely regarded to be limited. Methods of control have included chemicals, water manipulation, mowing, tillage, planting robust mudflat species such as Japanese millet (Thompson 1989), and, most recently, biological control using insects (Malecki et al. 1993).
Our objective was to compare avian use of vegetation zones dominated by loosestrife with other wetland zones where loosestrife was absent or not dominant. Comparison of avian breeding species richness, density, and diversity is a necessary first step to assess the value of loosestrife-dominated habitats to birds, and ultimately to evaluate costs and benefits of loosestrife control.