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Drowning while snorkeling is the leading cause of death among all water-based activities in Hawaii. But as long as you know and manage the possible risks, it can be easy, fun, and safe.

The water was clear and the sky was cloudless, so illumination was good underwater. The ocean was warm: 71F, too warm for kelp. El Niño is having an effect.

Pacific Jack Mackerel tend to visit the California coast in late summer, often in big schools.

I learned to dive at Refugio Beach. It was fun to visit it last week, in August 2026, a little more than 28 years after my first dive there.

Kelp Perch (Brachyistius frenatus) Kelp perch are like little gold coins, glittering as they dart and hover in schools, just below the kelp canopy. They are skittish, and reflect light well; it's tricky to capture their golden color. This kelp perch was enjoying a small stand of kelp off Sea Lion Beach, on the South (or "back") side of Anacapa Island. It seems like just about every group of fish has a species that begins with "kelp": kelp perch, kelp bass, kelp rockfish, kelp

Tube anemones are members of the genus Pachycerianthus, and have lovely tentacles. Many tube anemones are fluorescent.

Scorpionfish (Scorpionidae) This scorpionfish was relaxing on the bottom at Piedra Partida, a dive site at Danzante Island in the Sea of Cortez. Danzante Island lies in the Parque Nacional Bahía de Loreto, a spectacular reserve covering nearly 800 square miles of ocean and uninhabited islands. The Scorpionfish family is widespread throughout the Pacific and contains many species organized into several subfamilies and many genera. I am not sure of the species: several species

Eelgrass provides important habitat for young fish and other small creatures, but is susceptible to storms.

Red-eye Medusa (Polyorchis penicillatus) This Red-Eye Medusa had drifted into nearshore kelp at Refugio Beach. They are said to prefer eelgrass beds, of which there are a few off Refugio Beach. The red spots contain light-sensing organs, as well as red pigment. They add a touch of fashion. The interior structure looks kind of like a banyan tree, but is part of the digestive system, helping to distribute nutrients throughout the medusa. Red-eye Medusas are found along the east

The kelp forest at Landing Cove at Anacapa. This cove became a marine reserve in 1978, with no fishing or hunting allowed, so it has a lot of big lobsters and lush marine life.

This giant kelpfish was particularly friendly and patient as I photographed it off San Clemente Island.

Giant kelp (Macrocystis) can grow by splitting the frond on the top of a stalk, or "stipe", into many fronds.

A barnacle extends its cirri to scoop small prey from the water, while another has retracted its cirri to examine what they have netted. Both barnacles and the surrounding substrate are covered with red corynactis anemones

This is the exuvia, or cast-off exoskeleton, of a growing young barnacle

A Norris' Topsnail climbs a gas bladder on giant kelp It might look like this Norris' topsnail is a bubble dancer. But, he or she is doing the unending task of these snails, climbing a giant kelp (Macrocystis pyrifera), and feeding off the tiny animals that live on its surface. This shot was made looking straight down. These snails usually clamp their shells onto the kelp surface when approached. Perhaps this one was consumed with getting around this particular large kelp bla

Spirorbis extend their netlike feeding tentacles from the mouths of their tiny shells. These tiny worms have settled in a crevice in a frond of oarweed.

A colony of bryozoans (Membranipora membranacea) on a kelp blade Kelp fronds often carry white spots. Darwin mentioned them, on kelp off Chile, in his bestseller Voyage of the Beagle. This white spot is composed of many cells, grouped around a center. Each cell contains an individual bryozoan, a Lacy Crust Bryozoan or Membranipora membranacea. A single individual is known as a zooid (which is a great scrabble word). Here you can see that the zooids are a filter-feeders, sievi

Blades and air bladders of a macrocystis kelp swirl, as waves pass above.

Spanish shawl nudibranchs are among the most colorful of the denizens of the kelp forest.

Each yellow dot is a lottery ticket. A female Garibaldi laid these eggs a week or so ago, on a mat of red algae meticulously prepared by a male. The male then fertilized the eggs, and now guards them.