Kayak trips offer chance to see bioluminescence on Tomales Bay

Guided kayak tours take adventurers out in search of the tiny sea creatures who put on an eerie natural light show.|

If You Go

Spots fill up fast, but guided public or private kayak tours to view the bioluminescence in Tomales Bay are offered on moonless nights, including kayaks and full gear, by:

Blue Waters Kayaking

bluewaterskayaking.com

Point Reyes Outdoors

pointreyesoutdoors.com

Clavey Paddlesports

shop.clavey.com/bioluminescence-kayak-tours-on-tomales-bay-p1015.aspx

Outback Adventures

outbackadventures.com/trips_classes/kayaking/

It's fall, and while pumpkin hunters and spooky celebrations filled up much of October and November between Halloween and Day of the Dead, there's a different kind of supernatural event underway now that attracts a somewhat more adventurous crowd.

They gather in small groups on the banks of Tomales Bay in Marin, strapping on layers of gear as the sun sets behind the Point Reyes headland. In the orange glow of twilight they're preparing to paddle sea kayaks into the moonless night to experience an otherworldly scene: black waters teeming with sparkling, faint clouds of glowing life.

They're setting out to see the wild bioluminescent display (bioluminescent means ‘living light') that appears between July and early November in the 15-mile-long waterway.

The tiny creatures who do the glowing grow in numbers all summer long, and reach peak density at the start of fall. On calm nights in darkened coves, they put on a magical show for those willing to come out onto the water to meet them.

Several local outfitters stay busy guiding handfuls of kayakers into the Bay from the Marin County boat launch near Marshall to experience one of nature's more stunning and delicate displays.

As the sun sets, the guides coach their kayakers - a mix of novices, never-beens, and the more experienced - on the finer points of squeezing into the oval cockpits of the sleek, low two-seat watercraft, handling the twin bladed oar, and donning the necessary gear. After some limbering stretches, we pull waterproof parkas over our layered warm clothes, slip on a splash skirt that will seal water out of the cockpit opening, and buckle a life vest on top.

Down on the boat ramp the sun has gone, the sea air is chill, and the last warm tones of twilight are fading in the sky. We push off with a steady pull on the oars, into still waters, with the distant sound of breaking surf.

Tomales Bay is a narrow, long channel between wooded ridges. One end opens to the wild swells of the Pacific; at the other end is a tidal marsh, fed by the fresh water of the Lagunitas River.

The sheltered bay is a nursery and home for marine life, from harbor seals to sharks and anchovies, as well as tens of thousands of migrating sea birds, oysters and waving beds of long bright green eelgrass in the shallows. Wild coho salmon still find their way back here from the open sea, swimming far upriver to spawn.

It's an ancient place, sitting astride the San Andreas fault whose rock-grinding movement over tens of millions of years have opened the crack in the crust that's now filled with the seawater we float on.

Our guide, Liz Wilhelm from Blue Waters Kayaking, sets a steady pace west and we stroke and steer behind her, following the tiny orange light on her kayak's back deck as the night closes in. About a half mile in, she gathers our four kayaks into a ‘raft', and as we hold each other's lines and drift, she describes details of the Bay and its inhabitants. She has us look up at the Milky Way emerging overhead, and at the tall silhouettes of trees on Hog Island – our first destination. The wind is nearly dead calm, and the setting bright sliver of moon leaves a trail on the remarkably still black water.

Near Hog Island, our approach disturbs an unseen flock of cormorants roosting in trees overhead. A blue heron flies off with a scrawing racket.

Then, we see it. Dip a hand in, and the cool salt water winks with tiny sparkles of light, like drifting neon blue-white crystal dust.

For many thousands of years the Coast Miwok peoples lived along the bay, moving among gathering places on the shore and forests. Tsim Schneider, an archeologist and anthropologist at UC Santa Cruz, has extensively investigated evidence of the indigenous people who lived here. Their name for this water was Tamal-liwa. The region, he's discovered, also served as a refuge for native peoples fleeing the missions, and the displacements and savagery of the Gold Rush era.

Today the unique habitat and biological communities in Tomales Bay are protected within the federal Farallones National Marine Sanctuary. Karen Reyna, resource protection coordinator with the sanctuary, says the bay is a special natural place, with a concentration of high-value wildlife.

It is also internationally recognized, one of the rare spots designated by Ramsar, a global intergovernmental convention for the conservation of wetlands.

“The bay has a freshwater inlet at one end, and only one outlet to the sea, so the salinity or saltiness of the water is different mile by mile, from north to south, and changes with the incoming and outgoing tides,” Reyna says.

Banks of native eelgrass in the shallower water serve as nursery and protection for marine animals, including Pacific herring, California halibut, Dungeness crab and anchovy. Clans of harbor seals dive and pup here, and grey whales occasionally wander in come spring.

After a mile's paddling, guide Wilhelm circles the group again in shallows near the western shore. There's enough star glow to see the white cliffs of White Gulch Cove towering overhead.

And here the water swirls with clouds of blue light each time we pull an oar. Drops from the blade tips sparkle as they fall. Wilhelm tells us to watch for the meteor-like trails of small fish and bat rays moving down below.

The star performer of the night's light show is an incredibly tiny creature, Noctiluca scintillans, a single cell marine organism. Its Latin name translates to ‘glimmering night light', and it's a perfect fit.

The sparkle we see, Wilhelm tells us, is actually the shimmer of millions of Noctiluca winking on at the same time. Scientists haven't decided why they do it. It's thought they luminesce to distract or startle predators in the dark, or perhaps to put a glowing target around the shrimp-like krill which eat them. The light attracts hungry little fish, who eat the krill.

Bioluminescence, marine biologists have discovered, is far more frequent in sea creatures than once thought.

It's been found in various species of plankton, jellyfish, crustaceans and fish. In land animals like the firefly, and the tiny Noctiluca in Tomales Bay, the light is generated by a chemical reaction between two highly specialized molecules, Luciferin and Luciferase, named by the Frenchman who first isolated them in the 1800's.

The sparkle happens when a sudden physical disturbance in the water triggers a chemical reaction between the two chemicals. When they mix, they create a brief flash of light.

The little Noctiluca cells charge up in sunlight, and drift near the surface in late summer. There, masses of them can be triggered by sudden movement, of a fish, a hand, an oar, or surf.

While their light is not bright enough to be seen when the moon is out, on moonless nights it's visible to the naked eye, especially in the dark coves of the bay, where currents bring the creatures together in vast numbers.

Beneath the dome of sparkling stars in the clear sky overhead, we drift in the night and watch the smoky blue trails of our strokes in the water, then start back toward the tiny string of lights on the distant shore.

Stephen Nett is a Bodega Bay-based Certified California Naturalist, writer and speaker.

If You Go

Spots fill up fast, but guided public or private kayak tours to view the bioluminescence in Tomales Bay are offered on moonless nights, including kayaks and full gear, by:

Blue Waters Kayaking

bluewaterskayaking.com

Point Reyes Outdoors

pointreyesoutdoors.com

Clavey Paddlesports

shop.clavey.com/bioluminescence-kayak-tours-on-tomales-bay-p1015.aspx

Outback Adventures

outbackadventures.com/trips_classes/kayaking/

UPDATED: Please read and follow our commenting policy:
  • This is a family newspaper, please use a kind and respectful tone.
  • No profanity, hate speech or personal attacks. No off-topic remarks.
  • No disinformation about current events.
  • We will remove any comments — or commenters — that do not follow this commenting policy.