Secretive marsh bird occupancy across a spectrum of hydroelectric reservoir management in western montane Canada

Dam construction projects have created opportunities for water security, targeted flood protection, and energy production but at the cost of increasing anthropogenic pressure on affected aquatic ecosystems. Wetland ecosystems are often among most vulnerable, as underlying hydrological regimes influence overall wetland structure function. Marsh bird species riparian habitat specialists, many which experiencing population declines across North America. We examined how alteration generating hydroelectric power occurrence secretive marsh in western montane region British Columbia, Canada. established survey stations wetlands 2 regions, West Kootenay Columbia Wetlands, sampling a spectrum other potentially relevant factors. At each station, we assessed occupancy during breeding season using broadcast-callback surveys focused 5 species: American bittern (Botaurus lentiginosus), coot (Fulica americana), pied-billed grebe (Podilymbus podiceps), sora (Porzana carolina), Virginia rail (Rallus limicola). Additionally, measured vegetation proximity size nearby bodies station. then used models to assess important correlates behind these species, considering management operations, regional differences, local- landscape-level characteristics. Secretive were more likely occupy areas with less frequently altered regimes. Occupancy highlighted characteristics by birds. Wetlands had open cover tall present, conditions that negatively associated occupancy. Altered this study farther from next nearest wetland, was also suggest reservoir is altering communities within wetlands, indirectly promoting lower species.