Bryde's Whale

The Bryde’s whale (pronounced “broodus”) is a medium-sized baleen whale found in warm, tropical and subtropical waters worldwide — and one of the most unexpected encounters a diver or snorkeller can have in the Gulf of Thailand. Growing to 12–14 metres and weighing up to 20 tonnes, these whales are fast, elusive, and not nearly as famous as they deserve to be.

In Thailand

Bryde’s whales are the most commonly encountered large whale species in the Gulf of Thailand, though “commonly” is relative — these are still exceptional sightings. The nutrient-rich waters around Chumphon Pinnacle and the broader north Koh Tao area attract the baitfish schools and plankton blooms that draw the whales to feed. Sightings tend to cluster between February and April when surface productivity is at its peak.

Encounters are almost always at the surface — on the boat journey to or from a dive site, or occasionally while divers are in the water. The whale typically surfaces several times in quick succession to breathe before diving again, often remaining in the area for some time if conditions are calm and food is abundant.

Identifying a Bryde’s Whale

Bryde’s whales are often confused with sei whales or fin whales. Key features to look for:

• Three prominent ridges on the rostrum (the top of the head) — the defining characteristic, unique among baleen whales
• Slate-grey colouring, sometimes with pale streaks or mottling on the flanks
• A prominent, falcate (curved) dorsal fin set well back on the body
• A blow reaching 3–4 metres — tall and narrow

They are fast swimmers and rarely breach in the dramatic fashion of humpback whales, but surface lunge-feeding — bursting through baitballs with jaws agape — is sometimes observed and is extraordinary to witness.

Conservation Status

Bryde’s whales are listed as Least Concern on the IUCN Red List globally, though specific subpopulations face pressure from ship strikes, entanglement in fishing gear, and noise pollution. In the Gulf of Thailand, they receive no specific protection beyond general marine mammal regulations. If you encounter a Bryde’s whale, maintain a minimum distance of 30 metres, switch off engines if possible, and never approach head-on.

A Note for Divers

Underwater encounters are vanishingly rare but have been reported — a massive shape rising from the blue, completely silent, before disappearing again. If you’re lucky enough to hear whale vocalisations underwater near Chumphon Pinnacle, you’ll understand instantly why divers keep coming back to this site.