Nosy Be
Madagascar · Mozambique Channel
Nosy Be off Madagascar's northwest coast is the country's main diving hub — whale sharks September–December (juveniles, snorkel friendly), reef dives on surrounding islands, and Mozambique-channel biodiversity.
How this reef is doing
ⓘ How we measure thisReef state
Patchy reef condition across the area. Whale sharks Oct–Dec drive the season.
Coral cover
Fish life
Heat
No unusual heat right now.
Fishing
Some fishing is allowed here, in marked zones.
Sources · MERMAID and the survey teams · NOAA Coral Reef Watch · Global Fishing Watch and reef gravity
Coral cover over time
Live coral cover, by survey year
Across 8 survey years from 2016 to 2026, live coral cover here has risen from 45% to 47%. Every point is a real survey reading, never a projection.
Live coral cover, percent by year
| Year | Coral cover |
|---|---|
| 2016 | 45% |
| 2019 | 36% |
| 2020 | 38% |
| 2021 | 44% |
| 2022 | 48% |
| 2023 | 52% |
| 2025 | 29% |
| 2026 | 47% |
What you will see
22 species across the dive sites here
Madagascar Ground Boa
Seen 24 days ago
at Nosy Tanikely
Least concern
Hawksbill turtle
Seen 2 months ago
at Nosy Tanikely
Critically endangered
Green Sea Turtle
Seen 2 months ago
at Nosy Tanikely
Least concern
Hawksbill Sea Turtle
Seen 2 months ago
at Nosy Tanikely
Critically endangered
Madagascar Girdled Lizard
Seen 6 months ago
at Nosy Tanikely
Least concern
Varicose Wart Slug
Seen 8 months ago
at Nosy Tanikely
Fluted Giant Clam
Seen 9 months ago
at Nosy Mitsio
Least concern
Spiny Cushion Star
Seen 9 months ago
at Nosy Mitsio
Granulated Sea Star
Seen 9 months ago
at Nosy Mitsio
Whale Shark
Seen 9 months ago
at Coral Garden
Endangered
Honeycomb moray
Seen 10 months ago
at Nosy Tanikely
Least concern
Moorish Idol
Seen 10 months ago
at Nosy Tanikely
Least concern
Whitetip Reef Shark
Seen 10 months ago
at Coral Garden
Vulnerable
White-Tailed Tropicbird
Seen 11 months ago
at Nosy Mitsio
Least concern
Bumphead Parrotfish
Seen year round
at Nosy Tanikely
Vulnerable
Grey Reef Shark
Seen year round
at Nosy Mitsio
Endangered
Humphead Wrasse
Seen year round
at Coral Garden
Endangered
Lionfish
Seen year round
at Coral Garden
Least concern
Octopus
Seen year round
at Nosy Tanikely
Least concern
Scorpionfish
Seen year round
at Nosy Tanikely
Humpback Whale
Seasonal visitor
at Nosy Mitsio
Least concern
Manta Ray
Seasonal visitor
at Nosy Mitsio
Vulnerable
Dive sites
Nosy Tanikely
hawksbill turtle · honeycomb moray · octopus · scorpionfish
Nosy Tanikely
green sea turtle · bumphead parrotfish · hawksbill sea turtle · moorish idol
Coral Garden
whale shark · whitetip reef shark · humphead wrasse · lionfish
Nosy Mitsio
humpback whale · whale shark · grey reef shark · manta ray
What divers say
Whale sharks every day for a week, plus humpbacks on the boat ride. Madagascar punches above its weight.
Good to know
Cyclones
January–March cyclone risk; many ops close.