Catalina Islands
Depth is the range from the top of the site to its usual maximum; "recommended cert" is the mainstream-agency level operators usually ask for, not a legal rule. Currents and visibility change daily — treat everything here as planning ranges.
The Catalinas are a scatter of bare volcanic rocks a short run from the Flamingo and Tamarindo beaches, and they run on rays. Cool upwelled water from roughly November through May brings the headliners: giant Pacific mantas that wheel over the cleaning rocks, wingtips brushing the thermocline, along with mobulas in strings and spotted eagle rays in squadrons that can pass twenty strong. Whitetips nap under every ledge, octopus and morays fill the cracks, and the green, plankton-thick water that limits the view is precisely what sets the table. When a manta emerges from that murk, close and sudden, the site's reputation explains itself.
The moment you come for: Giant mantas in the cool months, eagle ray squadrons, easy logistics from Guanacaste's beach towns
Topography: Volcanic rock stacks, arches, and rubble slopes
Current: Papagayo-season flow feeds the site; drift-style dives around the rocks are standard.
Know before you splash
Hazards: Surge around the stacks, seasonal wind chop, plankton-limited visibility.
Conservation: Give mantas the right of way and never chase - encounters here depend on the animals choosing to stay.
Who you'll meet
Mobula (Devil) Ray
Oceanic Manta Ray
Spotted Eagle Ray
Whitetip Reef Shark
For photographers
Wide angle: ★★★★☆ · Macro: ★★☆☆☆ — editors' 1–5 rating of what this site gives each style of shooting