This uninhabited atoll is a possssion of the United States. The elongated island is 4.5 km² large and is low lying – rising up to 7 m above the sea level. This atoll currently has no lagoon and is dry, without freshwater.
The central part of the island though had a lagoon in the past. Now it is filled with thick layer of guano and is dry and thus represents an interesting geological phenomenon.
The island has scarce vegetation of grasses and rare low-growing shrubs. There is no evidence of prehistoric human settlements, but starting from late 19th century it has been periodically inhabited by guano miners and in 1935 – 1942 there was even established a small settlement named Millersville.
Remnants of all buildings were swept away without a trace by a very powerful storm in 1958, only day beacon remains.
Now the island is wildlife refuge and serves as nesting ground for huge number of birds and marine wildlife. Some species of birds here have their largest colonies – here are nesting many thousand pairs of masked boobies (Sula dactylatra), lesser frigatebirds (Fregata ariel), approximately one million pairs of sooty terns (Onychoprion fuscatus).