Isla de la Plata

Puerto López is a working fishing town that fills with whale-watching boats in season, and dive operators are a small part of that traffic. Boats head out in the morning for a two-tank day, and the run is long enough that you are committed once you leave the beach. Whether you dive the offshore bank or the sheltered rock nearer town is decided by the swell on the morning rather than by request, and a blown-out day is usually reshuffled rather than cancelled.

The water here is often green and soupy, and that is the point rather than the drawback: the plankton it carries feeds the filter feeders and keeps the cleaning stations busy. Thermoclines tend to arrive as sharp steps rather than gentle gradients, and the cold layer often sits right where the animals are working. Divers who need open blue water to enjoy themselves come up flat. Divers who came for animals rarely do.

The bank is dived by dropping onto the top of the rock and staying put while current runs over it, which needs a settled sea and is never a given on a chosen day. The island itself is dry and cliff-edged, with nesting boobies and frigatebirds along the trails, and park rules keep visitors with a guide ashore. Boats often pair the diving with that walk, so the surface interval can be spent looking at seabirds rather than sitting on a deck.

June through October is when the trip earns its reputation, with the oceanic manta season and the humpback season running almost in parallel. The rest of the year still runs. January to March is warmer and the water opens up, which makes the inshore rock pleasant and easy, but the large animals are largely elsewhere, and it is worth being honest about whether that changes what you came for. Intermediate experience and a tolerance for a bumpy crossing cover the rest.