Caribbean season: Holbox and Isla Mujeres
From mid-June to mid-September whale sharks aggregate east of Holbox to feed on tuna spawn. The site, called La Afuera, is the largest known whale shark aggregation in the world (200 to 400 sharks). Boats leave Holbox at 7 am and Isla Mujeres at 7:30 am. The boat ride is 1 to 2 hours and you spend 2 hours in the water taking turns swimming with the sharks.
Tours from Cancun, Playa del Carmen and Tulum exist but add 2 to 3 hours of round-trip transfer to that day. If your time matters, sleep on Holbox or Isla Mujeres the night before the tour and skip the early bus from the Riviera Maya.
Pacific season: La Paz, Sea of Cortez
From October to April juvenile whale sharks (3 to 7 meters) gather in La Paz Bay to feed on plankton. Encounters are intimate compared to Holbox: typically 3 to 5 sharks per outing, often visible from the boat without needing to motor far. La Paz tours leave at 8 am, last 4 hours and include marine biologist briefing, snorkel gear and ceviche lunch.
La Paz combines naturally with Cabo Pulmo bull and reef shark diving, Espiritu Santo island sea lion snorkel and a couple of Sea of Cortez wall dives. Five to seven days in Baja gives you all of these.
Holbox vs La Paz: side by side
| Holbox / Isla Mujeres | La Paz | |
|---|---|---|
| Season | Mid-June to mid-September | October to April |
| Shark numbers | 200 to 400 (aggregation) | 3 to 5 per outing |
| Boat ride | 1 to 2 hours offshore | 15 to 30 minutes |
| Cost | $140 to $200 | $110 to $160 |
| Best for | Spectacular numbers | Intimate, calmer water, combo with Cabo Pulmo |
Rules and etiquette
- 2 swimmers + 1 guide per shark, no exceptions, by federal law NOM-029-SEMARNAT-2006
- No scuba with whale sharks anywhere in Mexico
- No fins on the head of the shark, no flash photography, no touching
- Wear a 3 mm shorty wetsuit even in summer, the boat ride is cold
- Take Dramamine 1 hour before boarding if you are sea sick prone
Ready to swim with a whale shark?
Book a marine biologist guided whale shark snorkel from Holbox, Isla Mujeres or La Paz with free cancellation.
Preguntas frecuentes
No. Mexican law strictly prohibits scuba with whale sharks. Snorkel only, in groups of 2 swimmers per shark with a marine biologist guide.
Late July through mid-August is peak: highest shark numbers and warmest water. Season opens June 15 and closes September 15 by federal regulation.
Yes from age 5 if they snorkel comfortably. Holbox boats can be rough so smaller children may struggle. La Paz boats are calmer and family friendly.
