Hood Canal, Washington – One night last summer was an adventure in light. It was a very warm, still day, so we knew that we had a great chance of seeing light in the dark waters of Hidden Cove. We took our kayak paddles with us so we could stir the water and hopefully excite the organisms enough to light up. As we made our way across a very dark wooden dock, we noticed what looked like glitter shimmering here and there, like stars in a night sky. It was subtle, but there. We put our paddles in and sure enough, the light show began. We tried splashing, stirring, twirling, dripping, scooping and any other movement one can make with a paddle. The light was unmistakable, white with a hint of cool blue/green.
In the Pacific Northwest, the calm inlets and coves found in the Salish Sea are perfect places to see this phenomenon, known as Bioluminescence, which is the delightful ability of some organisms to produce light by an internal chemical reaction. Here, in the quiet waters of the Salish Sea, millions of microscopic plant-like organisms known as phytoplankton drift through the water and due to photosynthesis, multiply rapidly on warm, sunny days.
Dinoflagellates are one type of phytoplankton, and are the most common cause of the Bioluminescence seen in surface waters on dark, moonless nights. Another type of phytoplankton is the Coccolithophore, which is constructed with really cool looking calcium carbonate plates. A mass gathering of these spherical wonders can cause an over abundance of calcium carbonate (think Tums) in the water, which gives it a milky blue green appearance by day and a display of glow-in-the-dark hues at night. When there is a heavy bloom of this type of phytoplankton, it lights up our Hood Canal and other bays and inlets with an otherworldly glow that can be seen from space!
It is estimated that a staggering 90% of all marine organisms are able to produce light. Scientists are not completely sure how this particular skill helps each species, but it is believed that it can help organisms warn/escape predators, attract prey and/or communicate with members of their own kind. This breath-taking wonder occurs widely in marine vertebrates and invertebrates, but can also be found in some fungi, bacteria and terrestrial invertebrates such as fireflies.
As you track wonder on the ocean’s edges, think of the smallest members of the sea endowed with the ability to create stunning light… illuminating their world… and ours.
Cultivate Wonder… Discover Design
When and Where – On the Kitsap Peninsula, the Hood Canal is one of the best places to witness algal plankton blooms. In late summer after days of warm, sunny days, the water will look almost tropical near the town of Seabeck. Scenic Beach State Park (Discover Pass Required) is a great park with a stretch of public beach. If you are interested in seeing Bioluminescence, choose a warm, windless, moonless night in late summer, then find a place to peer into the water. Low docks make it easier to lie on your belly and watch for light, as well as stir the water to start the show!
Wonder Triggers for Young Trackers
- Did you know that ocean water is full of tiny organisms that spend their lives drifting along? They are called plankton and provide food for many sea creatures. See if you can find creatures who eat plankton. They often have feathery parts that catch plankton as it flows past. A good place to spot to see filter feeders is at a marina, where there are lots of poles and docks for the creatures to hang on to.
- If you have a microscope, get a little sea water and take a look through the lens. What do you see? What shapes do you see? Do you see anything moving?
References and Resources
NASA image used per Media Usage Guidelines Nasa Visible Earth
Coccolithophore Image – Alison R. Taylor (University of North Carolina Wilmington Microscopy Facility) used per Creative Commons Usage License
Jellyfish Image – NOAA – used per Creative Commons Used License