San José, Costa Rica, since 1956

Cold Water Attracts Marine Life to the Coasts

THE diving is hot throughout Costa Rica, but it’s getting cold as you drop deep.

Warm surface temperatures are bathing both coasts, however, cooler temperatures are layered below. The classically clear Caribbean’s warmth is cooling only slightly while dropping deep, but the Pacific’s underlying thermoclines are much cooler. CañoIsland’s deep layers have dropped as low as 65 Fahreinheit, (18 Centigrade) and Guanacaste reported a couple of days where it was even colder.

The cure is using all the wetsuit you can find. Many deep divers are even wearing hoods, although only a few are going as far as mitts. The water is green to yellow depending on the day and the light. The colors come from uncountable, almost microscopic, plants and animals called plankton.

Plankton is the soil of the ocean, the base of the vast food web of the sea. The cold water is thick like fog with plankton, which means a few extra sea life around to eat plankton. Even more predators come to eat the plankton eaters. The result is much marine life — and much wet suit.

DIVERS from Flamingo are reporting thousands of small rays around the Santa Catalina islets, which are thrilling divers. One day, a pack of Orcas showed up to eat the rays.

The Edge Adventures reports the action was intense and unforgettable for more than 20 minutes. Bill Beard’s Diving Safaris have excited divers at both the Catalinas and the BatIslands off Santa RosaNational Park in Guanacaste.

Guanacaste’s waters are clearing up as the Papagayo winds lay down and allow the clearer surface water back in to the dive sites.

Some of the marine life sightings include: breaching sperm whales, hundreds of spinner dolphins, giant mantas, silky and white-tip sharks, dozens of stingrays in mass mating, sailfish, big schools of massive yellowfin tuna, colossal big-eye tuna, bottlenose dolphins and many turtles for Drake Bay Wilderness Resort.

Also sighted were a rare beaked whale (beaked whales are seen less than jaguars) and a rare April showing of a humpback whale.

DRAKE Bay also lucked into nine straight days of a dolphin super pod of more than 1,000 dolphins offshore in 150 feet of visibility. A small fleet of longline fishing boats broke up the action and scattered the growing party that was insuring genetic dolphin diversity.

Before you decide to do it Pacific style, know that this time of year is prime Caribbean dive time (like September and October). It’s summer and the sea is flat.

Diving is easy in blue water right off the bright sandy beach. An incredible diversity of small fish, corals and sponges, together with mirror flat seas, making the south Caribbean a vast swimming pool full of things to see. There are no thermoclines, no currents and no surge inside the outer reef dives.

THESE dive sites contain the highest marine biodiversity of Costa Rica, especially small colorful reef life such as corals and sponges. Aquamor Adventures in Manzanillo reports classic Caribbean diving at press time. Aperfect time of year to get certified or advance in your dive training.

Productive, advanced Pacific diving or diverse, easy Caribbean diving? The choice is yours in Costa Rica. I recommend both.

For more info about diving in Costa Rica, call Shawn Larkin at 835-6041 or e-mail Also see the Web site at


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