Every year, tour operators gear up for “bioluminescence season” at a handful of destinations around the globe. It’s a phenomenon nearly as old as time itself, yet — according to a recent study by travel company and online search system Next Vacay, which set out to determine the most popular bioluminescent destinations on Instagram — Google searches for terms like “how to see bioluminescence” have increased as much as 400 percent over the last year, pointing to a renewed interest in the glowy, naturally occurring sensation.
Russell Markel, PhD, is a marine ecologist who has spent his life and career studying, exploring and sailing the coast of British Columbia, Canada. He’s also the owner and operator of Outer Shores Expeditions, a ship-based educational ecotourism company that combines Markel’s experience, education and passions to create experiences centered around education, creating awareness and stewardship.
Outer Shores Expeditions’ offerings are diverse and numerous. They explore some of the farthest reaches of the British Columbia coastline — in particular, the Haida Gwaii Archipelago, what’s known as Gwaii Haanas National Park Reserve and National Marine Protected Areas, as well as Canada’s Great Bear Rainforest. Guests are invited to explore ecosystems, learn about wildlife and address conservation-related questions and concerns with the help of marine ecologists, marine mammal specialists, cultural interpreters or coastal archeologists. They encounter tide pools on the shoreline, seabirds, whales, grizzly bears, spirit bears and, among other things — bioluminescence.
We spoke to Markel about all things bioluminescence: what it is, the best destinations to see it in action and the ideal time of year. Below, everything you need to know ahead of your next tour of the bioluminescent variety.
(Note that it has been edited and condensed for clarity):
What exactly is bioluminescence?
Bioluminescence is a phenomenon that occurs across a wide range of both flora and fauna. It’s found in microscopic algae, fungi, fishes and a wide range of invertebrates (marine invertebrates, in particular, but some terrestrial invertebrates, too).
In effect, it describes the ability of the aforementioned organisms to produce a cold, blue light. It’s a biochemical reaction, which comes as a result of a substrate called luciferin, mixing with an enzyme called luciferase. When those two molecules combine in conjunction with some energy coming from the cells of the animals, they produce light.
In fact, it’s one of the few known systems where light can be produced without producing heat. Of course, that’s all changing with the latest LED technology, but nature — from fireflies to angler fishes — had it figured out millions of years ago. That said, most bioluminescent tours are to see masses of single-celled algae called dinoflagellates (of which there are many species) that produce bioluminescence.
Where is this algae most commonly found?
In the broader category, these single-celled algae are known as phytoplankton — or, rather, microscopic plants of the sea. Like all plants (though these aren’t true plants), they utilize energy from the sun to produce their own sources of energy. They need sunlight, as well as other key nutrients like carbon, nitrogen and phosphorus, to survive.
Now, tropical seas tend to be fairly nutrient depleted. Alternatively, off the west coast of North America — from Baja all the way up through the coast of British Columbia and Alaska — the oceans are colder and more temperate. In the spring and summer, the winds circulating in conjunction with the rotation on the earth cause the surface waters of the oceans to be pushed away from land. As a result, that water that’s pushed away from land needs to be replaced, and it’s done so by water pulled up from the depths, which happens to be extremely nutrient dense.
The process, in its entirety, is called coastal upwelling and it’s a recipe for very high production, which is called primary productivity. In short, it’s why bioluminescence tends to be most abundant seasonally, in the spring through summer, and in higher latitude areas.
That’s not to say bioluminescence isn’t prevalent in the tropics — it is — but the difference is that it might be a gentle sprinkle of light some places in the tropics, whereas I’ve gone scuba diving at night and it feels like you’re in a light snowstorm. It’s so much — it’s thick, massive, bright. The bubbles light up, every time you move, you’re lit up. Everything is just exploding with bioluminescence, so there’s definitely a gradient.
That said, the western margins of the continents above or below the equator — so the west coast of North America starting about 30 degrees north, California to British Columbia and Alaska, or 30 degrees south off the coast of Chile and Peru — are areas that have the most incredible upwelling systems on the planet, and thus the highest regions of phytoplankton productivity and bioluminescence.
Does the appearance of bioluminescent light vary depending on the habitat and the organism in which it’s found?
Phytoplankton and dinoflagellates are ubiquitous throughout the ocean. They’re everywhere, but more abundant in these areas where you’re likely to get high levels of nutrients that support their productivity. That said, they’re completely different from jellyfish or deep sea angler fishes or zooplankton.
So while bioluminescence is found in all these different organisms, yes, it stands to reason that it would vary by habitat and organisms.
How is it that these simple organisms are able to do this?
From an ecological and evolutionary ecology perspective, bioluminescence has long been a topic of interest and the answers as to how it came to be are still varied.
In the case of phytoplankton, it’s presumably a defense mechanism. When zooplankton comes up and starts to chew on it, it flashes in hopes of scaring predators. In other cases, like with a zooplankton, they likely flash as a means to attract a mate of some kind. In other cases still, it’s a camouflage mechanism. In blending in with the ambient, it’s harder for predators to find them. Then there are angler fishes — complex vertebrates with little glowing, dangling fish lures hanging off of their head — that actually use bioluminescence to attract their prey.
All of this to say, even in the absence of a uniform explanation for its existence, the evolution of bioluminescence is fascinating.
There’s a huge conversation to be had about eco-friendly tourism and ecotourism. Is that prevalent here? What are things people should be mindful of?
The experience tour operators are referencing comes largely from being on a beach at night and seeing the waves crash and light up, or walking down a beach in the dark and seeing your footprints light up, or traveling in a boat and seeing the wake of the vessel light up. From a tourism and potential impacts perspective, phytoplankton are an unimaginably abundant marine organism. The impact that we have by waving our hand through the water, or a boat, is negligible.
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