Shark

Grey reef shark

Carcharhinus amblyrhynchos

IUCN status: EndangeredWidely sought

A classic requiem reef shark of Indo-Pacific drop-offs and channels, grey-bodied with a plain first dorsal fin and a broad black margin on the tail. It patrols current-swept reef walls and is far more common on remote offshore reefs than inshore. The IUCN uplisted it to Endangered in 2020 after steep declines.

Max size
Up to ~2.5m, usually under 1.9m
Habitat
Reef walls, drop-offs and channels

Best places to dive with Grey reef shark

rareoccasionalcommonly seenpeak season
Fakarava
Sighting likelihood by month
MonthLikelihood
Januarycommonly seen
Februarycommonly seen
Marchcommonly seen
Aprilcommonly seen
Maycommonly seen
Junepeak season
Julypeak season
Augustcommonly seen
Septembercommonly seen
Octobercommonly seen
Novembercommonly seen
Decembercommonly seen

The headline species. The South Pass holds a resident aggregation commonly counted at 300-700 grey reef sharks year-round. Densities peak around the June-July full moon when the sharks feed on spawning groupers. Present at both passes; sightings are reliable but exact numbers vary with tide and season.

Baa Atoll
Sighting likelihood by month
MonthLikelihood
Januarycommonly seen
Februarycommonly seen
Marchcommonly seen
Aprilcommonly seen
Maycommonly seen
Junecommonly seen
Julycommonly seen
Augustcommonly seen
Septembercommonly seen
Octobercommonly seen
Novembercommonly seen
Decembercommonly seen

Resident on Baa's outer reefs and channels year-round, with a grey reef shark nursery at Anga Faru. Sightings favour current-swept channel and thila dives rather than any season.

Hin Daeng & Hin Muang
Sighting likelihood by month
MonthLikelihood
Januarycommonly seen
Februarycommonly seen
Marchcommonly seen
Aprilcommonly seen
Maycommonly seen
Junecommonly seen
Julycommonly seen
Augustcommonly seen
Septembercommonly seen
Octobercommonly seen
Novembercommonly seen
Decembercommonly seen

Grey reef sharks are among the more reliable large animals here, patrolling the deeper walls of both pinnacles.

Komodo
Sighting likelihood by month
MonthLikelihood
Januarycommonly seen
Februarycommonly seen
Marchcommonly seen
Aprilcommonly seen
Maycommonly seen
Junecommonly seen
Julycommonly seen
Augustcommonly seen
Septembercommonly seen
Octobercommonly seen
Novembercommonly seen
Decembercommonly seen

Concentrated on the northern seamounts — Castle Rock and Crystal Rock, where operators report them patrolling daily — rather than spread through the park. Also reported at Langkoi Rock in the far south. Year-round; no seasonal pattern found in the sources reviewed. Best seen hooked in on the current-facing side, which is why this is an advanced-site animal.

Palau
Sighting likelihood by month
MonthLikelihood
Januarycommonly seen
Februarycommonly seen
Marchcommonly seen
Aprilcommonly seen
Maycommonly seen
Junecommonly seen
Julycommonly seen
Augustcommonly seen
Septembercommonly seen
Octobercommonly seen
Novembercommonly seen
Decembercommonly seen

Resident at Blue Corner, Ulong and Peleliu; numbers and activity peak March–May around the full and new moons.

Ribbon Reefs & Cod Hole
Sighting likelihood by month
MonthLikelihood
Januarycommonly seen
Februarycommonly seen
Marchcommonly seen
Aprilcommonly seen
Maycommonly seen
Junecommonly seen
Julycommonly seen
Augustcommonly seen
Septembercommonly seen
Octobercommonly seen
Novembercommonly seen
Decembercommonly seen

Resident and commonly seen in the passes and along outer reef walls, especially in current at sites like Dynamite Pass. Year-round; not seasonal.

Tubbataha Reefs Natural Park
Sighting likelihood by month
MonthLikelihood
Januarycommonly seen
Februarycommonly seen
Marchcommonly seen
Aprilcommonly seen
Maycommonly seen
Junecommonly seen
Julycommonly seen
Augustcommonly seen
Septembercommonly seen
Octobercommonly seen
Novembercommonly seen
Decembercommonly seen

The most reliable shark here — grey reef sharks appear on nearly every dive, often in groups of several, patrolling the walls and drift sites like Washing Machine and Amos Rock.

Alor
Sighting likelihood by month
MonthLikelihood
Januaryoccasional
Februaryoccasional
Marchoccasional
Apriloccasional
Mayoccasional
Juneoccasional
Julyoccasional
Augustoccasional
Septemberoccasional
Octoberoccasional
Novemberoccasional
Decemberoccasional

Patrol the current-swept pinnacles, notably Kal's Dream and Sharks Galore off Pura, alongside whitetip reef sharks.

Northern Red Sea
Sighting likelihood by month
MonthLikelihood
Januaryoccasional
Februaryoccasional
Marchoccasional
Apriloccasional
Mayoccasional
Juneoccasional
Julyoccasional
Augustoccasional
Septemberoccasional
Octoberoccasional
Novemberoccasional
Decemberoccasional

An occasional wall and blue-water encounter in the north, chiefly at Tiran. Grey reef sharks are far more reliable on Egypt's southern offshore reefs (the Brothers, Daedalus) than around Sharm.

Sipadan
Sighting likelihood by month
MonthLikelihood
Januaryoccasional
Februaryoccasional
Marchoccasional
Apriloccasional
Mayoccasional
Juneoccasional
Julyoccasional
Augustoccasional
Septemberoccasional
Octoberoccasional
Novembernot seen
Decemberoccasional

More common at South Point and the deeper wall (Sipadan closed in November).

Surin Islands (Mu Ko Surin)
Sighting likelihood by month
MonthLikelihood
Januaryoccasional
Februaryoccasional
Marchoccasional
Apriloccasional
Mayoccasional
Juneoccasional
Julyoccasional
Augustoccasional
Septemberoccasional
Octoberoccasional
Novemberoccasional
Decemberoccasional

Reported at Koh Torinla and exposed reef edges; less frequently seen than the shallow-reef blacktips.

Truk Lagoon
Sighting likelihood by month
MonthLikelihood
Januaryoccasional
Februaryoccasional
Marchoccasional
Apriloccasional
Mayoccasional
Juneoccasional
Julyoccasional
Augustoccasional
Septemberoccasional
Octoberoccasional
Novemberoccasional
Decemberoccasional

Occasional around the wrecks and lagoon passes; not the reason to come here.

Bunaken
Sighting likelihood by month
MonthLikelihood
Januaryrare
Februaryrare
Marchrare
Aprilrare
Mayrare
Junerare
Julyrare
Augustrare
Septemberrare
Octoberrare
Novemberrare
Decemberrare

Occasionally seen in the blue off the more exposed points such as Sachiko's, but far less reliable than the reef whitetips and blacktips.

Vava'u
Sighting likelihood by month
MonthLikelihood
Januaryrare
Februaryrare
Marchrare
Aprilrare
Mayrare
Junerare
Julyrare
Augustrare
Septemberrare
Octoberrare
Novemberrare
Decemberrare

Reported occasionally on Vava'u reefs but the least commonly seen of the three reef sharks here.

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.

Note on the data: Shared species (Northern Red Sea and Baa Atoll). IUCN status was Near Threatened before the 2020 uplisting to Endangered; older sources may still cite Near Threatened. The IUCN Red List PDF URL may 403 to automated fetches but resolves in a browser.