Roca Partida is the smallest of the Revillagigedo Islands

Revillagigedo Islands

The Revillagigedo Islands or Revillagigedo Archipelago are a group of four volcanic islands in the Pacific Ocean, known for their unique ecosystem...

 in Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

, administrated by the state of Colima

Colima

Colima is one of the 31 states which, with the Federal District, make up the 32 Federal Entities of Mexico. It shares its name with its capital and main city, Colima....

. It is uninhabited, with an area of only 1.4 hectares (3.5 acre).

Like the other islands in its group, it is volcanic in origin, but unlike San Benedicto

San Benedicto Island

San Benedicto, formerly Santo Tomás, is an uninhabited island, and third largest island of the Revillagigedo Islands, located in the Pacific at ....

 and Socorro

Socorro Island

Socorro Island is a small volcanic island in the Revillagigedo Islands, a Mexican possession lying some 600 kilometers off the country's western coast at 18°48'N, 110°59'W. The size is 16.5 by 11.5 km, with an area of 132 km².- Geology :...

 which are still active, Roca Partida has eroded

Erosion

Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...

 to a piece of bare rock, devoid of terrestrial vegetation. It is some 100 metres (328.1 ft) long and about 8 metres (26.2 ft) wide, and rises into two peaks divided by a low-lying area - hence the name. These were some 25 and 34 m (82 and 111.5 ft) high in 1953 but the higher one appears to have eroded several meters since then (see photo below). No land animals or fresh water occur on Roca Partida.

A number of seabird

Seabird

Seabirds are birds that have adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations...

s breed here:

• Nazca Booby
  Nazca Booby
  The Nazca Booby, Sula granti, is a booby which is found in the eastern Pacific Ocean, namely on the Galápagos Islands where it can be seen by eco-tourists, and on Clipperton Island...
  
  ,
• Northeast Pacific Brown Booby
  Brown Booby
  The Brown Booby is a large seabird of the booby family, Sulidae. The adult brown booby reaches about in length. Its head and upper body are covered in dark brown, with the remainder being a contrasting white. The juvenile form is gray-brown with darkening on the head, wings and tail...
  
  ,
• East Pacific Sooty Tern
  Sooty Tern
  The Sooty Tern, Onychoprion fuscatus , is a seabird of the tern family . It is a bird of the tropical oceans, breeding on islands throughout the equatorial zone. Colloquially, it is known as the Wideawake Tern or just wideawake...
  
  , a doubtfully distinct subspecies
  Subspecies
  Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
  
  
• East Pacific Brown Noddy
  Brown Noddy
  The Brown Noddy or Common Noddy is a seabird from the tern family. The largest of the noddies, it can be told from the closely related Black Noddy by its larger size and plumage, which is dark brown rather than black...
  
  ,

For the first two named, Roca Partida is one of the most north-easterly breeding sites.

Roca Partida is considered one of the most beautiful dives in Mexico. It is a military zone so permits must be obtained to go there.

External links

• Marine Life of Roca Partida
• Scuba Diving in Roca Partida
• Photo. Retrieved 2007-NOV-21.
• Information page with map
• Photo of Roca Partida