Tobi, or Hatohobei[2] (Tobian), is the southernmost of Palau's sixteen states,[3] consisting of Tobi Island and Helen Reef. The total land area is about 0.88 km². The population was 25 in 2015. Tobian, English and Sonsorolese are the official languages of Hatohobei State.


Flag of Hatohobei
Location of Hatohobei in Palau
Location of Hatohobei in Palau
Country Palau
 • Total0.9 km2 (0.3 sq mi)
 • Land0.9 km2 (0.3 sq mi)
 • Water0 km2 (0 sq mi)
 • Total25[1]
ISO 3166 codePW-050

It is the least populous first-level administrative subdivision in the world.

Political systemEdit

The state of Tobi, with population of 25, has an elected chief executive, governor. The state also has a legislature elected every four years.[4] The state population elects one of the members of the House of Delegates of Palau.


The individual islands of Hatohobei, together with the islands of the state of Sonsorol, form the Southwest Islands of Palau.

No. Island Satellite
Population 2015 Coordinates
1 Tobi (Hatohobei)   0.85 0 03°00′22″N 131°07′26″E / 3.00611°N 131.12389°E / 3.00611; 131.12389 (Tobi)
2 Helen Reef (Hotsarihie)   0.03 3 02°57′N 131°47′E / 2.950°N 131.783°E / 2.950; 131.783 (Helen Reef)
3 Transit Reef (Pieraurou) - - - 02°47′N 132°32′E / 2.783°N 132.533°E / 2.783; 132.533 (Transit Reef)
State of Hatohobei Hatohobei 0.88 3  

Tobi IslandEdit

A bai on Tobi Island, 1971

Tobi (Hatohobei or Kodgubi) Island was once the main island of the state (together with the permanently manned Marine Ranger Station on the second island, Helen Island). The land area is 0.85 km². Its highest point is 6 m, while most of the island is less than 3 m high. Most of the houses are situated in the abandoned village of Tobi (Hatohobei) on the southwestern side of the island, the state capital. The island is covered with coconut palms. A cultivated area was situated near the center of the island. The island is fringed by a reef that extends up to 800 m from the shore in the north.

Map of Helen Reef (Hotsarihie)
Helen Island
Tern rookery on Helen Island

Helen ReefEdit

Helen or Helens Reef (Hotsarihie), about 70 km east of Tobi Island, is a largely submerged atoll, with just one islet (Helen Island). The atoll is 25 km long and nearly 10 km wide, with a lagoon area of 103 km² and a total area including reef flat of 163 km². A channel leads into the lagoon from near the middle of the western side of the reef. Immediately south of the channel is Round Rock, which dries. The lagoon has about 85 patch and pinnacle Reefs.

When the tide is falling, the water flows out of the lagoon and over the reef in all directions until the reef is uncovered, and then flows out through the channel on the western side. On the rising tide, a reverse effect is noted. Only few parts of the reef completely dry.

Helen IslandEdit

Helen island was discovered by the Spanish naval officer Felipe Tompson in 1773, who charted it as San Felix shoal.[5] The only island of the reef, it is located near its northern tip. It is tiny in comparison to Helen Reef, about 20 to 40 m wide and 400 m long, or about 0.03 km² of land area. The densely wooded island sits atop a sand dune, which is 0.25 km² in extent and which is moving southeast, falling into the lagoon, at a rate 3 to 4 m per year. The island is uninhabited except for a marine ranger station of Hatohobei State, which was established in the early 1990s on the eastern side of the island, to guard the reef against foreign poachers. The station is permanently occupied by a staff of three.

The island has been designated an Important Bird Area (IBA) by BirdLife International because it supports a breeding colony of black noddies, with some 25,000 birds estimated in 2004. There are also nesting populations of sooty and greater crested terns.[6]

Transit ReefEdit

Satellite picture of Helen Reef with supposed location of Transit Reef marked with circle

50 km east of Helen Reef is Transit Reef (Pieraurou), which appears on some maps and which is referenced as an island in the Hatohobei State constitution and constitutes the southernmost feature of Palau. Its existence as island, however, is doubtful, as it is not listed in the current Sailing Directions. The literal translation of its Tobian name Pieraurou is "Sandy Navigation Point", referring to a submerged sand bar rather than a reef or island.

See alsoEdit


  1. ^ [1]
  2. ^ Community Consultations on Marine and Terrestrial Resource Uses. Palau Conservation Society. 2003.
  3. ^ Vitarelli, Margo (1998). Olechotel Belau. Belau National Museum.
  4. ^ "State/National Election Schedule". Palau Election Commission. 5 November 2020.
  5. ^ Brand, Donald D. The Pacific Basin: A History of its Geographical Explorations The American Geographical Society, New York, 1967, p.132.
  6. ^ "Helen Island, Hatohobei". BirdLife Data Zone. BirdLife International. 2021. Retrieved 2 March 2021.

External linksEdit