New York Harbor's ___ Island (5)
(Other definitions for ellis that I've seen before include "- Island, former reception point for US immigrants" , "- - Peters (novelist)" , "who wrote sexy books?" , "-- Bell, Bronte pen name" , "- Peters, wrote Brother Cadfael books" .)
(Other definitions for staten that I've seen before include "- Island, New York City borough" , "New York borough and island in Bay" , "Nat set out for NY Island" .)