Urban green roofs play an important role in wildlife conservation by providing suitable habitat for arthropods, birds, and bats in areas dominated by impervious surface. However, little is known about wildlife community develop on green roofs over time. We monitored arthropod, bird, and bat use of a single large (27,316 m2) Sedum green roof in New York City for nine years, beginning the year the roof was installed. We collected arthropods using bowl and pitfall traps, conducted bird surveys, and monitored bat activity using acoustic recording units. We also banded nesting and pre-fledge Herring Gulls (Larus argentatus). Arthropod and bird abundance was high the year of installation but decreased substantially in the year following installation. Over time, both arthropod and bird abundance increased to levels similar to the year of installation, although the increase in bird abundance was largely due to a growing Herring Gull colony. Arthropod taxa richness and bird species richness rapidly increased in the years following installation, with some annual variation, and the accumulation of new species slowed over time. We recorded four species of bats over the roof. Bat activity increased over time, with most activity occurring during fall migration. At least one Herring Gull that hatched on the green roof returned to nest on the green roof four years after hatching. We demonstrate dynamic change in a wildlife community using a large green roof in the years following installation. Our results provide a case study of how a green roof can provide an enduring wildlife habitat in a highly urbanized and rapidly changing landscape.