Meet at Grand Army Plaza Arch, Flatbush Ave and Prospect Park West at Eastern Pkwy, Prospect Heights, Brooklyn. Subway: 2, 3 to Grand Army Plaza.
Bike from Prospect Park to the Green-Wood Cemetery with a guide from Prospect Park Audubon Center (that'd be Gabriel Willow). Along the route, you'll be able to view of the area's birds, including its nesting parrots (bring binoculars).