Linking Wetland Management Decisions to Distribution, Habitat Use and Nesting Efforts of Secretive Marsh Birds in Missouri
July 2012 - June 2016
- Missouri Department of Conservation
Secretive marsh birds (SMB) encompass a group of wetland dependent birds including rails, bitterns and moorhens. Extensive wetland habitat loss throughout the United States is believed to have contributed to the subsequent decrease in geographic range of many SMB species. In addition, SMB are generally inconspicuous and tend to inhabit wetlands with robust, perennial vegetation making them difficult to detect. Overall, limited distributions combined with low detection probability have resulted in SMBs being among the least studied avian groups and for most species there is limited information on population levels, breeding ecology, migration patterns and overall habitat requirements. Wetland managers make repeated decisions that vary spatially and temporally as they attempt to ensure their management actions result in a diversity of habitat types and water depths to provide for the life history needs of wetland-dependent wildlife. Missouri’s wetland managers focus on emulating system processes to provide suitable conditions to fulfill the life history needs of the full suite of waterfowl and other wetland-dependent wildlife. Ensuring these conditions necessitates that managers consider landscape setting, the types and magnitude of alterations to these settings, timing of bird movements, water distribution, and habitat distribution. Decisions regarding the timing and location of management actions are often driven by knowledge gained through observations and experience. A primary assumption of wetland management in Missouri is that wetlands managed for the full suite of waterfowl species will also provide essential habitat for many species of wetland-dependent wildlife to fulfill their life history needs, including SMBs. While studies of wetlands along the Missouri River provided some evidence to support this assumption in regards to shorebirds and wading birds, there are integral gaps in our knowledge of how SMB respond to the vegetative and habitat conditions resulting when wetlands are managed primarily for migrating waterfowl.