Nature at Night on Tomales Bay

Photo by Tim King courtesy of Blue Waters Kayaking

Celebrating the Wonders of Bioluminescence in our Backyard

By Sandra Ann Harris

MARSHALL, Calif. -- It was a dark and quiet night on Tomales Bay with a cloud cover blanketing the sky. The thought of wiggling into my skintight wetsuit didn’t excite me, but I was intrigued by the possibility of seeking magical bioluminescence in Tomales Bay.

I was expecting a wild goose chase, and I was nervous about heading out on a cool night in a little inflatable boat. I could vaguely recall the dramatic scene in “Life of Pi” with the boy on the raft surrounded by magically sparkling and glowing waters. Surely, that was a computer-generated cinematographic effect?

Our family has had a home on Tomales Bay in the Point Reyes National Seashore in Northern California for 15 years, and I’ve spent many weekends gazing out at its lovely waters.  But I’d never seen or given much credence to tales that periodically the bay would bloom with glowing bioluminescence that would illuminate the waters.

My husband, Thinh, fired up the outboard on our small inflatable boat and we headed out towards a little beach just south of Hog Island. It was a dark moonless night. The cloak of night was falling over the soft still waters and the feeling of peace on earth was intoxicating. A couple of stars were starting to peek out overhead as we chugged across the sliver of water that makes up Tomales Bay. 

When we disembarked on a lonely stretch of beach, at first we thought there was nothing to see. The waters were dark and unremarkable. But when the final rays of twilight smudged to complete darkness, our children noticed as they played in the water that the splashes they were making with our paddles seemed a little whiter and brighter than usual.

And when we entered the water to splash more and explore the shallows, we saw that the turbulence we created with our footsteps stirred up glowing little flecks. In excitement we splashed more, and more bioluminescence blossomed beneath our feet. Frightened fish nearby darted away from us, creating glowing streaks.

The marine planktons responsible for this spectacular effect are called dinoflagellates, a living organism, according to researchers at the Bodega Marine Laboratory. The tiny dinoflagellates emit short flashes of light when disturbed and put on quite a show, but in Tomales Bay, the bluish flickers are visible only on dark moonless nights. 

Seals chasing the fish create a phosphorescent event, which can also be very exciting to watch. Schools of fish in the bay create a bright trail that looks like a glowing cloud in the water. Night herons are sometimes out and about as well, chasing the same schools of fish. 

All this glowing activity is only visible at night when the sun and moon are both down. For kayakers, the bay becomes a glowing playground, with the paddles making glowing streaks in the water. A local outfitter Blue Waters Kayaking offers tours in the late summer and fall when it’s mostly likely bioluminescence might be present.

As we splashed, teardrops of water danced around us like magical confetti. It was an incredible experience in nature with my family that I’ll always remember... playing, laughing and marveling at the real-life fairy dust from Tinkerbell's wand in the big blue of our Tomales Bay! I look forward to the next time we’ll have the chance to scoop up a handful of water and watch illuminated water pour through our fingers like tiny diamonds!

Writer and eco adventurer Sandra Ann Harris is the founder of ECOlunchbox.

Photo credits: David Allen Studio