You do not need a submarine. Some of the most spectacular bioluminescence on Earth can be seen from a kayak, a boardwalk or a forest trail.
Conditions, seasons, rules and tour availability change. Always check with the local park, tourism board or tour operator before you travel.
Glowing water
Mosquito Bay
Where
Vieques, Puerto Rico
What glows
Dinoflagellates (Pyrodinium bahamense)
Best time
Year-round, on dark nights near the new moon
Often called the brightest bioluminescent bay in the world, and recognized as such by Guinness World Records in 2006. Tours go out by kayak or electric boat; swimming in the bay is not allowed, to protect it.
Laguna Grande and La Parguera
Where
Fajardo and Lajas, Puerto Rico
What glows
Dinoflagellates
Best time
Year-round, darkest nights
Together with Mosquito Bay, these make Puerto Rico home to three of the best-known bioluminescent bays anywhere. Laguna Grande is reached by kayak through a mangrove channel.
Luminous Lagoon
Where
Trelawny, near Falmouth, Jamaica
What glows
Dinoflagellates
Best time
Year-round, after dark
Where a river meets the sea, this lagoon glows blue-green when boats move through it or visitors trail a hand in the water.
Toyama Bay
Where
Toyama Prefecture, Japan
What glows
Firefly squid (Watasenia scintillans)
Best time
Roughly March to June
Each spring, huge numbers of firefly squid rise toward the surface to spawn, lighting the bay in blue. Early-morning sightseeing boats go out to watch, and part of the bay is protected as a Japanese Special Natural Monument.
Beaches of the Maldives
Where
Islands including Vaadhoo, Maldives
What glows
Plankton in the surf
Best time
Unpredictable -- depends on plankton blooms
On the right night, the surf glows blue along the shore, an effect nicknamed the "sea of stars". It depends on plankton blooms, so it is never guaranteed.
Indian River Lagoon
Where
Space Coast, Florida, USA
What glows
Dinoflagellates and comb jellies
Best time
Warm months, on dark nights
Guided night kayak tours paddle through water that sparkles with every stroke. Fish darting under the boat leave glowing trails.
Glowing caves, forests and fields
Waitomo Glowworm Caves
Where
North Island, New Zealand
What glows
Glowworms (Arachnocampa luminosa)
Best time
Year-round
Guided tours finish with a quiet boat ride under a cave ceiling covered in thousands of tiny blue-green lights. Photography is restricted inside to protect the glowworms.
Great Smoky Mountains National Park
Where
Elkmont area, Tennessee, USA
What glows
Synchronous fireflies (Photinus carolinus)
Best time
A couple of weeks between late May and mid June
Thousands of males flash together in waves, then go dark at the same time. The event is so popular that the park uses a lottery for access during the peak viewing period.
Congaree National Park
Where
South Carolina, USA
What glows
Synchronous fireflies (Photuris frontalis)
Best time
Typically mid May to early June
Another US national park with fireflies that flash in rhythm, here in a floodplain forest. Check the park's website for event dates and any reservation system.
Dark, damp forests near you
Where
Many temperate and tropical regions
What glows
Foxfire and glowing mushrooms
Best time
Warm, wet nights; often late summer and autumn
Look for rotting logs and fallen branches on a moonless night after rain. Switch off your light and give your eyes time to adjust before giving up.
Responsible viewing tips
Bioluminescent places are fragile. A few simple habits help keep them glowing for the next visitor.
Go dark. Plan around the new moon, and stay away from street lights and phone screens. Your eyes need about 20 to 30 minutes to fully adjust to the dark.
Skip the flash. Flash photography and bright lights disturb fireflies and glowworms. If you need a light, use a dim red one and point it at the ground.
Stay on the trail. Many fireflies rest and lay eggs in the grass and leaf litter at your feet.
Keep sunscreen and bug spray out of the water. Where swimming is allowed, chemicals on your skin can harm plankton. Where it is not allowed, do not swim.
Choose licensed, low-impact tours. Kayaks and electric boats are kinder to bays than gas motors.
Leave it as you found it. Do not collect fireflies, mushrooms or water samples from protected areas.
