Gregory J. Soulliere

DENSITY OF SUITABLE WOOD DUCK NEST CAVITIES IN A NORTHERN HARDWOOD FOREST

The density of natural cavities suitable for wood duck (Aix sponsa) nesting, and the relative importance of cavity and potential cavity tree species were determined in a second growth hardwood forest in central Wisconsin. Suitable cavity density averaged 0.65/ha, with silver maple (Acer saccharinum), sugar maple (A. saccharum), quaking aspen (Populus tremuloides), and American basswood (Tilia americana) containing suitable cavities. These 4 species, which typically occur in Wisconsins wet-mesic and mesic woodlands, were of highest importance in the forests composition of large (-31 cm diameter breast ht (dbh)) trees. Although the density of suitable wood duck nest cavities was not high, cavities are nevertheless abundant because large areas of forest are available for wood duck nesting. Numbers of cavities should increase as Wisconsins second growth forests continue to mature. Wildlife managers will have a greater impact on wood ducks by advising on forestry operations, rather than actively providing nest sites.

Monitoring Waterfowl in the Midwest during the Non-breeding Period: Challenges, Priorities, and Recommendations

Abstract Habitat conservation planning for migrating and wintering waterfowl is typically based on the estimated foraging needs of populations occurring in areas during these non-breeding periods. However, several factors limit the value of historic population data collected by wildlife agencies in the Midwest region. Survey protocols lack standardization and a statistically-based sampling framework, and the financial burden of surveys often falls on individual agencies, sometimes precluding annual completion during times of limited budgets. Environmental factors and human disturbance are thought to affect distribution of waterfowl during migration, yet these parameters have rarely been included in survey design, impeding efficient assessment of key population influences. Fortunately the importance of monitoring to achieve effective bird conservation has been elevated in recent years. In the Midwest, topical scientific forums regarding bird monitoring have resulted in development of new working groups and...

Change in Density of Duck Nest Cavities at Forests in the North Central United States

Abstract During the past century, clear-cut hardwood forests of the north central United States have regenerated, and trees have matured into size classes increasingly capable of producing cavities...

Post-Breeding and Early Migrant Bird Use and Characteristics of Diked and Undiked Coastal Wetlands in Michigan, USA

Abstract. Bird use of diked and undiked Michigan coastal wetlands (n = 17) was studied on Lake St. Clair and Lake Huron during late July to mid-October, 2005–2007. Relative abundance and diversity were compared via aerial (n = 9) and ground (n= 155) surveys and wetland characteristics were measured. Species richness and similarity indices suggested analogous bird use, but multivariate analyses indicated significant separation in diked and undiked bird assemblages. Wood Duck (Aix sponsa), Great Blue Heron (Ardea herodias), and Wilsons Snipe (Gallinago delicata) were more abundant on diked sites, whereas dabbling ducks combined, Mallard (Anas platyrhynchos), American Black Duck (A. rubripes), gulls (Laridae), Forsters Tern (Sterna forsteri), and Greater Yellowlegs (Tringa melanoleuca) were more abundant on undiked wetlands. Wetland characteristics also differed. Diked sites were primarily cattail (Typha spp.) marshes interspersed with small open-water areas containing aquatic plants. Undiked sites had larger openings fringed with bulrushes (Schoenoplectus spp.), fewer aquatic plants, and direct lake connections. Periodic drawdowns of diked wetlands could encourage greater plant species and structural diversity, making them more attractive to dabbling ducks. However, risk of common reed (Phragmites australis) expansion is high in the study areas, thus its control may be necessary before enhanced management can occur.