Influence of water level management on vegetation and bird use of restored wetlands in the Montezuma Wetlands Complex

Active water management of wetlands promotes seed and tuber production to
feed migrating waterfowl, but few assessments exist to determine how
management actions influence wetland structure, vegetation, and bird
response throughout the year. We identified effects of full water
drawdown, partial water drawdown and passive wetlands (no active
dewatering during the growing season) on plant communities and bird
abundance in wetlands of the Montezuma Wetlands Complex, New York,
May–October 2016–2018 and February–April 2017–2019. We detected few
differences in the plant community during June, but during September we
detected greater vegetative forage quality index for waterfowl, annual
plant cover and seed density in full and partial drawdowns than passive
wetlands. Bird abundance was greater in June–July in passive
wetlands and greater in September–October in full drawdowns. During spring
migration, duck densities were greater in full and partial drawdowns. Our
results indicate that wetland managers should use a mix of full drawdowns
and passive wetlands to provide habitat for the greatest diversity and
number of birds throughout the year.