Scuba Diving in Catalina Island

Diving in Catalina Island is the easiest way to experience California's giant kelp forests. The island sits about 22 miles off the Los Angeles coast, an hour by ferry from Long Beach, San Pedro, or Dana Point. Drop below the surface and you're weaving through kelp stalks that grow up to two feet per day and stretch 60 feet or more from the reef to the surface. Bright orange garibaldi patrol the rocks, sea lions buzz your safety stop, and from July through October, giant sea bass the size of small couches cruise the kelp line.

Conditions here reward every experience level. Casino Point Dive Park in Avalon is a protected, no-take marine reserve with stair entry, making it one of the best shore dives in the United States and a natural first ocean dive for new divers. Boat dives along the island's leeward coast reach kelp reefs, walls, and caverns, while advanced divers can head to open-ocean pinnacles like Farnsworth Bank and Ship Rock for purple hydrocoral and deep drop-offs.

Expect water temperatures from the mid 50s °F (around 13 °C) in winter to the low 70s °F (around 23 °C) at the height of summer, with visibility typically 30 to 60 feet (9 to 18 m) and days that stretch past 80 feet (24 m) in fall and winter. This is temperate diving, so a 7 mm wetsuit or drysuit is the norm for most of the year. Logistics are simple: take the morning ferry, dive with one of Avalon's operators or walk into the dive park, and be back on the mainland by dinner. Catalina also has a safety net few destinations can match, a 24/7 emergency hyperbaric chamber located right on the island.

Best dive sites in Catalina Island

The best dive sites in Catalina Island range from a walk-in dive park you can reach on foot from the Avalon ferry landing to open-ocean pinnacles that demand advanced skills. Here are the five worth planning your trip around.

Casino Point Dive Park

Casino Point is the classic Catalina dive, a 2.5-acre underwater park at the base of Avalon's landmark Casino building. Established in the 1960s as the country's first nonprofit underwater park and designated a no-take State Marine Conservation Area in 2012, it packs healthy kelp forest, several small wrecks, and a plaque honoring Jacques Cousteau at 40 feet into one easy shore dive. Entry is via a staircase straight into calm, protected water, so there's no surf to fight.

You'll descend through kelp alive with garibaldi, señoritas, kelp bass, and sheephead. Work your way out to the Sue-Jac wreck in the 60 to 90 foot range, or find the swim-through at the Kismet and glass-bottom boat wreckage. In summer and early fall, keep an eye on the outer kelp edge, where giant sea bass patrol. Air fills and gear rentals are available steps from the entry point.

Depth: 20–95 ft (6–29 m) | Level: All Levels

Farnsworth Bank

Farnsworth Bank is Catalina's bucket-list dive. This series of open-ocean pinnacles rises from around 200 feet (60 m) to peaks at about 55 to 60 feet (17 to 18 m), roughly five miles off the island's rugged backside. The draw is purple hydrocoral, a slow-growing California specialty that carpets the ridges here in dense colonies, mostly between 100 and 130 feet (30 to 40 m). The site sits within the Farnsworth Offshore State Marine Conservation Area.

This is blue-water diving. You'll drop down a line into open ocean, and currents and swell can be significant. In exchange you get oceanic visibility, schools of blacksmith and rockfish, torpedo rays, and regular sea lion flybys. Operators require Advanced Open Water or equivalent, and conditions have to cooperate for boats to make the run around the island's exposed side.

Depth: 55–130+ ft (17–40+ m) | Level: Advanced

Ship Rock

Ship Rock is a guano-topped pinnacle breaking the surface about a mile and a half off Two Harbors, and it just keeps going underwater, dropping past 120 feet (37 m) to sand. Circle the rock through kelp and boulder terrain, and pick your depth: shallow ledges full of gorgonians and nudibranchs, or deeper walls where the terrain falls away fast.

Sea lions are the stars here. The rock hosts a rowdy crowd that loves to dive-bomb bubbles. Current can pick up on the ocean side, so this one suits divers with a few ocean dives in their log. Deep-certified divers can push the sand line for halibut and bat rays.

Depth: 20–120+ ft (6–37+ m) | Level: Intermediate

Blue Cavern Point

Blue Cavern Point, just east of Two Harbors, is Catalina's best wall dive. The rock face drops past 130 feet (40 m), decorated with sea fans and honeycombed with caves and caverns in the shallows that you can poke into with a light. Boats run it as a drift, so you'll fly along the wall with minimal effort while the boat follows your bubbles.

The site sits within the Blue Cavern State Marine Conservation Area, and the protection shows: dense fish life, lobster tucked into cracks, and healthy kelp along the top of the wall. Visibility here is often among the best on the island's front side.

Depth: 15–130+ ft (5–40+ m) | Level: Intermediate

Italian Gardens

Italian Gardens, on Catalina's east side, is the island's most reliable spot for giant sea bass. From July through October, these fish, which can top 7 feet and 500 pounds, gather where the kelp meets the sand in the 40 to 70 foot range (12 to 21 m). Hang quietly at the kelp edge and they'll often approach on their own, close enough to fill a wide-angle lens.

Outside sea bass season it's still a satisfying dive, with kelp beds from 30 to 100 feet (9 to 30 m), mild to moderate current, and the usual Catalina cast of garibaldi, sheephead, and bat rays over the sand.

Depth: 30–100 ft (9–30 m) | Level: All Levels

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Best time to dive Catalina Island

The best time to dive Catalina Island is July through October, when water temperatures climb to 68–74 °F (20–23 °C), seas are calm, and giant sea bass aggregate along the kelp line. If visibility is your priority, winter is the sleeper season: colder water, fewer divers, and vis that can stretch to 80–100 feet (24–30 m) on the best days.

Summer weekends bring the biggest crowds to Casino Point, so aim for weekdays if you can. Spring plankton blooms feed the ecosystem but can drop visibility for stretches, worth checking a current dive report before you book.

Diving conditions

Marine life in Catalina Island

Marine life in Catalina Island centers on the giant kelp forest, one of the richest temperate ecosystems in the world. The neon-orange garibaldi (California's state marine fish) is everywhere, joined by kelp bass, señoritas, California sheephead, rockfish, and giant kelpfish hiding in plain sight among the fronds.

Giant sea bass (black sea bass): July to October, especially around Italian Gardens and Casino Point

The signature encounter. These protected giants grow past 7 feet (2 m) and 500 pounds (227 kg), and they've rebounded around Catalina after decades of protection. Look for them where the kelp meets the sand in the 40–70 ft (12–21 m) range in summer and early fall.

California sea lions: year-round, especially around Ship Rock

Playful, fast, and curious, sea lions show up on most boat dives and love mugging divers at Ship Rock.

Purple hydrocoral (Stylaster californicus): year-round, especially around Farnsworth Bank

A rare, slow-growing coral found at only a handful of California sites. Farnsworth's colonies are the reason advanced divers make the trip around the island's backside.

• Pelagics: Giant sea bass, yellowtail, barracuda, bat rays, occasional blue and mako sharks offshore
• Macro life: Nudibranchs, blue-banded gobies, octopus, zebra gobies in the rocky reef
• Reef dwellers: Garibaldi, California sheephead, kelp bass, señorita, horn shark, moray eel, California spiny lobster, leopard shark in the shallows

Catalina's waters are ringed by nine marine protected areas. Casino Point and Blue Cavern Onshore are no-take conservation areas, Long Point is a full State Marine Reserve, and Lover's Cove and Farnsworth are conservation areas with limited take. The giant sea bass, once fished nearly to local extinction, is the poster child for the recovery those protections made possible.

Discover more marine life on Divearoo's global heatmap.

Practical information

Dive prices

• Two-tank boat dive: around $160 including gear (recent diver reports; confirm current rates with operators)
• Casino Point Dive Park: free to dive; gear rentals and air fills available on site
• Ferry: from $42 each way per adult on Catalina Express (Long Beach or San Pedro; Dana Point is $2 more), plus about $5 in wharfage fees and tax

Getting there

No airport logistics here. Catalina Express runs up to 30 daily departures year-round from Long Beach, San Pedro, and Dana Point, reaching Avalon in about an hour. A seasonal ferry also runs from Newport Beach, and helicopter charters fly from Long Beach. From the Avalon ferry landing, Casino Point is a 15-minute walk along the harbor. Dive boats depart from Avalon; sites on the island's front side are minutes away, while Farnsworth Bank on the backside is a longer, conditions-dependent run. Two Harbors, near Ship Rock and Blue Cavern, has its own dive and recreation center.