Los Arcos National Marine Park

Did You Know?

• The larger arches are big enough for a motorboat to be driven through them.
• A rocky 250 m wall on the western side of the islets offers two dive sites.
• Devil's Rock is named for a cliff shadow that looks similar to Satan.

History

The arches were originally hills of the Sierra Madre Occidental near the coast. Ocean erosion gradually exposed their granite centers and separated them from the mainland. In 1975 the area was declared a Refuge Area for the Protection of Marine Flora and Fauna due to reef damage and overfishing, and in 1984 it was reclassified as a National Marine Park.

Description

The five islets are composed of granite and lie 12 km south of Puerto Vallarta. The three largest arches are Roca de Los Arcos, Roca de la Tortuga, and Roca del Diablo, the latter named for a cliff shadow resembling Satan. The surrounding waters may be the deepest in the Bay of Banderas, reaching 480 m, and the islets are visible from the downtown district.

Wildlife

The park is an important breeding ground for birds such as osprey, blue-footed boobies, parakeets, cormorants, and pelicans. Marine life includes king angelfish, Pacific sergeant major, giant oceanic manta ray, zebra moray, garden eels, octopuses, and rarely sea turtles. From November to March, humpback whales, orcas, and dolphins are more common, and bioluminescent plankton appears at night.