SYMPOSIUM PRESENTER TITLE: Changes in breeding-bird communities of the Lower Wisconsin Riverway and the effects of climate ABSTRACT: The diverse plant-animal communities of the Lower Wisconsin Riverway, the transitions between them, and the connections with adjacent landscapes support a rich array of breeding birds. Bird populations further respond to habitat changes associated with the dynamics of hydrology, water quality, weather, succession, management, habitat conversion and connectivity, disease, and invasive plants, as well as factors outside the riverway, like range expansions. I overview these population responses and Riverway-scale trends based on several sources, including periodic week-long canoe-surveys of the entire riverway conducted between 1984 and 2025. Climate change is an increasingly dominant driver of bird habitat dynamics and longterm habitat change in the river floodplain. Extensive summer floods kill trees, converting many tracts of floodplain forest and scattered trees into expanses of snag-studded marsh, open water, and buttonbush swamp—or, where the flooding is shallow, into beds of reed-canary grass that inhibit tree regeneration. This loss of floodplain forest is exacerbated by the ravages of tree diseases. Forest birds such as Red-shouldered Hawk have declined, and although cavity nesters like Red-headed Woodpecker and Prothonotary Warbler have benefitted, they may decline as snags collapse. Forest birds are not simply replaced by marsh birds, because riverway marshes open to strong flooding accumulate little residual plant material upon which many marsh birds and their prey breed and feed. These changes should be evaluated in light of others in and near the floodplain, e.g., where floodplain forest might expand, adapt, or convert to other habitats; and considering projected increases in flood and drought events. BIO: Mike Mossman is a retired Wisconsin DNR research ecologist. He continues to work on land management and study conservation, wildlife and history in the Driftless Area, especially Sauk County. He has worked on Lower Wisconsin River ecology and management issues since the 80s, and co-wrote applications for its Important Bird Area and Ramsar designations.