We report a two-year field experiment that solicited residents of Jamestown, Rhode Island, USA, to contribute funds to support contracts with farmers willing to provide a portfolio of public goods associated with improving the nesting success of grassland birds, particularly the Bobolink. A direct-mail marketing experiment collected funds through four provision point, money-back guarantee mechanisms: a voluntary contribution mechanism with a proportional rebate; a pivotal mechanism based on the Clarke tax; and two novel uniform price auction mechanisms. Valuation estimates recovered from the voluntary contribution mechanism approached that of the pivotal mechanism, with one uniform price auction falling lower.