Ocean

ocean
freediving
sharks
marine-life
The ocean is four billion years old and practically a Goddess. Freediving, sharks, and what the water teaches.
Updated

May 15, 2026

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Swim out into the ocean alone before dawn. The bioluminescent dinoflagellates light up around you each time you move or a swell passes by. It’s like swimming among stars. You feel the energy exchange between your body and the Ocean water. A swell lifting you up and setting you back down. You’re out in the Ocean alone. You hear a sea lion, or something, break the surface and drop back under water. Something is hunting out here. And you’re part of the ecosystem whether you realize it or not. It will take you about two microseconds to feel the vast energy and power in the water and understand who is really in control.

Freediving is the same. You are placing your trust in the Ocean, your body, your training and equipment, your freediving partners. It is trust and surrender to the Ocean. It is, in essence, a spititual experience.

I often think about how the Ocean is a strange and ancient thing. Loren Eiseley wrote, in his 1957 Book The Immense Journey, that “If there is magic on this planet, it is contained in water.” Water itself is a strange substance and where you find water Life is possible. Now imagine a planetary-scale body of salt water, several billion years old, from which all life on Earth emerged. It drives the climate, the oxygen cycle, and the food webs that everything else depends on. It is a vast reservoir of energy on which all life on Earth depends.

This is why the ocean matters to my work. Not as a study site or a data source — as the thing that makes the work make sense. The bioacoustics, the passive acoustic monitoring, the work on how to listen to living systems at scale — it all comes from the same source as the freediving. A felt sense of what is actually out there, what it sounds like, what it is doing, why it matters. You cannot fake that from a desk.

La Jolla before dawn. (Photo: Jeff A. Tracey)

Freediving

After a snorkeling trip to Molokini during a visit to Maui and Oahu in 2014, I started freediving. Back in San Diego, I found Dive California and trained with Michael Timm, completing SSI and PADI freediving certifications.

Here I am ascending after a constant weight bifins dive. (Photo: Paul Knepper)

Recreational freediving in southern California. (Photo: Michael Timm)

I do a lot of line diving, but my favorite thing is to explore marine environments and encounter wildlife — not as a researcher, just as a creature in the water with other creatures. Freediving has been one of the most positive things I have ever done for myself. It is also, without question, a spiritual experience.

Here I share some of the places and animals I have encountered. More stories to come.


Sharks

Three leopard sharks (Triakis semifasciata) over a sandy bottom in shallow water. A common sight in the calm bays and nearshore areas of Southern California — large aggregations form seasonally, particularly females in warm shallows. (Photo: Jeff A. Tracey)

Aerial view of a leopard shark aggregation in the shallows near La Jolla. The seasonal aggregations can number in the hundreds; this shot was taken with a drone at roughly 30 meters altitude. (Photo: Jeff A. Tracey)

Tope shark (Galeorhinus galeus) in open water. A wide-ranging coastal species once heavily targeted by directed fisheries for its liver oil. (Photo: Jeff A. Tracey)

Horn shark (Heterodontus francisci) in rocky reef habitat — a banded guitarfish (Zapteryx exasperata) tail is also visible at the edge of the frame. Both are common residents of Southern California kelp and rocky reef. (Photo: Jeff A. Tracey)

Banded guitarfish (Zapteryx exasperata) resting under a rock ledge on a Southern California reef. Despite the name, guitarfish are rays — the flattened body and broad pectoral fins are adaptations for life on the bottom. (Photo: Jeff A. Tracey)

Broadnose sevengill shark (Notorynchus cepedianus) — San Diego kelp forest. (Video: Jeff A. Tracey)

Oceanic whitetip shark (Carcharhinus longimanus) — open ocean off Kona, Hawaii, 2018. The white fin tips that give the species its name are clearly visible. Once one of the most abundant large sharks in the open ocean; now severely depleted. (Photo: Jeff A. Tracey)

Sea Turtles

Green sea turtle (Chelonia mydas) over a Southern California reef, with a garibaldi (Hypsypops rubicundus) — California’s state marine fish — visible in the background. Green sea turtles were once severely depleted along this coast; populations have recovered substantially under legal protection. (Photo: Jeff A. Tracey)

More to come.