Reef fish
Bumphead parrotfish
Bolbometopon muricatum
The largest parrotfish, reaching about 1.3–1.5m and 45kg, with a bulbous forehead used in head-butting displays. It grazes coral in schools and gathers in spawning aggregations; harvest is banned in several countries.
- Max size
- Up to ~1.5m and 45kg+
- Habitat
- Outer reef slopes and channels; sleeps in shallow reef
Best places to dive with Bumphead parrotfish
| Month | Likelihood |
|---|---|
| January | occasional |
| February | peak season |
| March | peak season |
| April | peak season |
| May | peak season |
| June | occasional |
| July | occasional |
| August | occasional |
| September | occasional |
| October | occasional |
| November | occasional |
| December | occasional |
Resident schools on the outer reef; a mass spawning aggregation is documented in Palau around the new moon, strongest February–May.
| Month | Likelihood |
|---|---|
| January | commonly seen |
| February | commonly seen |
| March | commonly seen |
| April | commonly seen |
| May | commonly seen |
| June | commonly seen |
| July | commonly seen |
| August | commonly seen |
| September | commonly seen |
| October | commonly seen |
| November | commonly seen |
| December | commonly seen |
A resident school lives on and around the USAT Liberty at Tulamben and is often seen at dawn before day-trippers arrive.
| Month | Likelihood |
|---|---|
| January | commonly seen |
| February | commonly seen |
| March | commonly seen |
| April | commonly seen |
| May | commonly seen |
| June | commonly seen |
| July | commonly seen |
| August | commonly seen |
| September | commonly seen |
| October | commonly seen |
| November | not seen |
| December | commonly seen |
Big schools cruise the reef top at dawn (Sipadan closed in November).
| Month | Likelihood |
|---|---|
| January | commonly seen |
| February | commonly seen |
| March | commonly seen |
| April | commonly seen |
| May | commonly seen |
| June | commonly seen |
| July | commonly seen |
| August | commonly seen |
| September | commonly seen |
| October | commonly seen |
| November | commonly seen |
| December | commonly seen |
Herds of 20–40 are a common Tubbataha sight, grazing across the reef flats and shallow coral.
| Month | Likelihood |
|---|---|
| January | occasional |
| February | occasional |
| March | occasional |
| April | occasional |
| May | occasional |
| June | occasional |
| July | occasional |
| August | occasional |
| September | occasional |
| October | occasional |
| November | occasional |
| December | occasional |
Groups graze the reef tops, most often encountered around Mandolin and the eastern walls.
| Month | Likelihood |
|---|---|
| January | occasional |
| February | occasional |
| March | occasional |
| April | occasional |
| May | occasional |
| June | occasional |
| July | occasional |
| August | occasional |
| September | occasional |
| October | occasional |
| November | occasional |
| December | occasional |
Reported year-round in schools at Lighthouse in the north and Tanjung Loh Sera, but not a given on any single dive — coded occasional rather than resident because the sources describe them site-specifically rather than as a park-wide constant. No seasonality documented.
| Month | Likelihood |
|---|---|
| January | occasional |
| February | occasional |
| March | occasional |
| April | occasional |
| May | occasional |
| June | occasional |
| July | occasional |
| August | occasional |
| September | occasional |
| October | occasional |
| November | occasional |
| December | occasional |
Reported at boulder sites such as Boulder City/Shark Fin Reef, often in loose groups. Present through the open season; sightings vary by site.
Sources & last checked
Checked July 2026
This is a researched draft, not yet human-verified. The seasonality and logistics are drawn from the sources below — confirm specifics (permits, fees, closures) with an operator before you book.
- Bolbometopon muricatum (Bumphead Parrotfish) — IUCN Red List of Threatened Species
- Green humphead parrotfish — Wikipedia
Note on the data: Shared species (Palau and Sipadan).