Indonesia · North Sulawesi
Bunaken
Best wall and turtle diving generally aligns with drier months and better visibility.
Bunaken sits at the northern tip of Sulawesi in a marine park famous for its sheer wall diving — drop-offs that plunge 200m+ into deep blue, draped in soft coral and sponges, with turtles, schooling barracuda, and reef sharks patrolling the edges. Nearby Lembeh and Bangka round out a north-Sulawesi diving triangle.
Good season
March–October is the main season; year-round divable. Water temp is a steady 27–29°C.
Trip duration
5–7 nights resort-based on Bunaken or mainland Manado.
Dive style
Wall and drift diving with mild current; easy buoyancy practice.
Dive level
Open Water; the walls are forgiving and the marine park is well-managed.
Reef health
What you’ll actually findOne of the few reefs whose live coral has held up over the last decade. Plan with confidence.
Coral reef health
How is this calculated?On current trend, no live coral by ~2249. Losing about 0.2% cover per year — roughly 225 years of reef left to see if nothing changes.
Heat stress right now
Mild warmth. Worth watching — no bleaching yet.
NOAA Coral Reef Watch · updated May 2026 · 0 °C-week heat dose
What to expect on a dive
Bunaken's wall diving remains the highlight. Some shallow flats show bleaching scars but the drop-offs hold their cover.
Sources, methodology, and the raw numbers
Raw observed numbers
- Coral cover: 45% (survey Sep 2024, Reef Check Indonesia/Malaysia/Philippines survey)
- Bleached: 8%
- Recent mortality: 2%
- Coral Triangle — observed condition reflects the stable regional pattern.
Raw thermal numbers
- NOAA CRW alert level: Watch
- Degree Heating Weeks: 0 °C-wk
- SST anomaly: +0.3 °C
How we summarise this
Observed coral cover, bleaching, and mortality come from named in-situ surveys with a stated date and method — they describe one snapshot of one reef and do not extrapolate to neighbouring sites. Current thermal stress is satellite-derived from NOAA Coral Reef Watch at ~5 km resolution; it indicates risk, not observed coral damage. We deliberately separate observed condition, current thermal stress, and projection — and we never publish a projection without a documented model and uncertainty.
Sources
- Reef Check — Reef Check Foundation
- NOAA Coral Reef Watch — U.S. National Oceanic and Atmospheric Administration
- AIMS Long-Term Monitoring Program — Australian Institute of Marine Science
- Global Coral Reef Monitoring Network — GCRMN / ICRI
- Atlantic and Gulf Rapid Reef Assessment — AGRRA Program / Perry Institute for Marine Science
- NOAA National Coral Reef Monitoring Program — NOAA Coral Reef Conservation Program
- NOAA CoastWatch / OceanWatch — NOAA NESDIS / STAR
- Allen Coral Atlas — Arizona State University Center for Global Discovery and Conservation Science
- Great Barrier Reef Marine Park Authority — Australian Government
- International Coral Reef Initiative — ICRI Secretariat
- Reef Life Survey — Reef Life Survey Foundation
- NASA PO.DAAC — NASA Jet Propulsion Laboratory / Caltech
- Copernicus Marine Service — Mercator Ocean International for the European Union
- NASA Ocean Color (OB.DAAC) — NASA Goddard Space Flight Center / Ocean Biology Processing Group
- Argo float network — International Argo Program / UCSD
- CoralWatch — University of Queensland
- IMOS / AODN — Integrated Marine Observing System / Australian Ocean Data Network
- WRI Reefs at Risk Revisited — World Resources Institute
- Ocean Health Index — OHI partnership (Conservation International + UCSB + NCEAS)
- IPCC Special Report on the Ocean and Cryosphere (SROCC) — Intergovernmental Panel on Climate Change
- GOA-ON — Global Ocean Acidification Observing Network — GOA-ON Secretariat + IOC-UNESCO
- HAEDAT — Harmful Algae Event Database — IOC-UNESCO Intergovernmental Panel on Harmful Algal Blooms
- NCEI Marine Microplastics — NOAA National Centers for Environmental Information
Reef condition changes year to year. If you visit, consider supporting responsible-travel and conservation operators on the ground.
Pressure on this reef
Protection · fishing · what you can doProtected-area status
Strict MPAInside a strict marine protected area with active enforcement.
Fishing pressure
Moderate fishing pressureDominant pressures
- dynamite/cyanide fishing legacy
- tourism
- plastic
3 Green Fins-verified operators known at this location.
What you can do
Bunaken Marine National Park has been formally protected since 1991 with village-based ranger patrols. Local marine sanctuaries are well-run; the wider region still recovering from decades of destructive fishing. Choose dive shops that pay sanctuary fees directly to the village.
Protection status sourced from Protected Planet / WDPA and refined with Marine Protection Atlas. Fishing pressure proxy is Global Fishing Watch AIS data. See the methodology for what these sources can and can’t prove.
Dive sites here
5 curatedLekuan Walls
Three contiguous wall sections (Lekuan I, II, III) along the south side of Bunaken island, dropping from the reef crest to over 200 m. Brist…

Bunaken Timur
The eastern wall of Bunaken island, generally lighter current than Lekuan and consistently good for pelagic encounters in the blue. Big scho…

Hairball (Lembeh Strait)
Black volcanic sand slope on the Sulawesi side of the Lembeh Strait, considered the flagship muck dive of the world's macro-diving capital. …

Wakatobi
Wakatobi National Park is renowned for its exceptional marine biodiversity, featuring vibrant coral reefs, dramatic walls, and diverse ecosy…

Derawan Islands
The Derawan Islands, located off the coast of East Kalimantan, Indonesia, are a remote and biodiverse dive destination. Known for extensive …
Gear
What to bringWhat divers say
“Bunaken's walls feel infinite. You drift along the top and the reef just falls away below you forever.”