Waterfowl

Aix sponsa

Lophodytes cucullatus

Wood ducks ( Aix sponsa ), and hooded mergansers ( Lophodytes cucullatus ) are two cavity nesting ducks that commonly use artificial nest boxes in central Wisconsin . The student chapter of the Wildlife Society at Stevens Point maintains 50 nest boxes located in backwater sloughs of the Wisconsin River north of Stevens Point , and 45 boxes on the Portage County Wildlife Club land west of Stevens Point . The boxes and their upkeep were donated to TWS after a graduate student from LSU was finished with his graduate project. Each winter in January, we check the boxes for use and change the cedar shavings to prepare the houses for the new nesting year. We determined box use by checking boxes for unhatched eggs, pieces of egg shells, and egg membranes. Wood duck eggs are smaller, more oblong, tan, and have thinner shells, whereas hooded merganser egg shells are larger, more round, white, and have thicker shells. We have recently analyzed data collected in the winters of 2004 and 2005 for a comparison of nest box use between wood ducks and hooded mergansers and presented the findings at the Student Research Symposium. We compared site variables of used boxes such as box height, nest box opening direction, distance to nearest edge, and proximity to other used boxes to determine if there is a difference in box selection and use between the two species. We discovered that wood ducks seem to prefer nest box openings that face more northeast, whereas hooded mergansers seem to prefer next box openings that face southeast.