The Banda Sea pelagic calendar
October through April is the Banda Sea dry season — calm seas, clear water, and peak pelagic activity. Within that window, October-November sees the strongest hammerhead activity at Pulau Run. December-February brings consistent mola (oceanic sunfish) sightings at Pulau Hatta and Banda Neira. March-April produces the highest pelagic diversity (hammerheads, mola, manta, and occasional oceanic whitetip). Late April to early May is the transition month — still good diving, but some operators begin pulling boats.
Hammerhead season at Pulau Run
Pulau Run’s western wall drops to 600m+ within 50m of shore. The thermocline meets the wall at 25-35m and produces conditions where scalloped hammerheads (Sphyrna lewini) school. Schools of 30-100 individuals are recorded October to November, with peak sightings in the new-moon weeks. Divers must be Advanced Open Water minimum, comfortable in 2-3 knot current, and willing to descend quickly to 30m to maximize bottom time at the pelagic zone. Drift dives are typical — the boat picks up at the surface.
Mola encounters at Pulau Hatta
Mola — oceanic sunfish — are most reliably encountered at Pulau Hatta from December through February. The dive site has a deep wall drop to 60m+ and a thermocline that pulls cooler water from depth, attracting mola for cleaning. Sightings are not guaranteed — mola behavior is unpredictable — but the wall is rich enough in soft corals and reef fish to make the dive worthwhile regardless. We log 30-40% mola sighting rate during peak season at Hatta.
Manta sightings — less reliable
Banda Sea manta sightings are occasional, not seasonal. Pulau Ai’s deeper southern wall produces 1-2 manta encounters per voyage in our experience. The sightings are typically reef mantas (Manta alfredi), not the larger oceanic mantas. Operators who tell you Banda is a ‘manta destination’ are exaggerating — Komodo and Raja Ampat are far better for manta. We mention them when they happen.
Other pelagic sightings
Eagle rays are common year-round. Reef sharks (whitetip, blacktip, gray reef) are routine. Tuna and trevally schools are seasonal — October-December peak. Occasional pelagic thresher shark and mobula sightings. Spotted eagle rays at multiple sites. Whale sharks are rare in the Banda Sea — Cenderawasih Bay (Papua) is a far better whale shark destination.
How to plan your voyage for pelagic priorities
If hammerheads are your priority: book October or November departures. If mola is your priority: book December-February. If you want maximum pelagic variety: book March-April. Our voyage calendar lists each departure’s expected pelagic profile based on multi-year sighting data. Email us if you want voyage-by-voyage probability estimates — we update them quarterly.
