Seventh in a series on Puerto Rico.
Mosquito Bay is located east of Esperanza on the coast of the Caribbean Sea. It is by no means the only bioluminescent bay in the world, which occur in tropical waters when bioluminescent microorganisms become highly concentrated in an area. In 2006, the Guinness Book of World Records declared Mosquito Bay to be the brightest in the world. The guide on our Island Adventures tour told us that few of the world’s “Bio-Bays” have been studied in detail. If so, it is unclear how Guinness was able to make this authoritative declaration.
The bay is vital to the Vieques tourist industry. After all, though Vieques has many wonderful beaches, it is by no means unique among Caribbean islands in this regard. The presence of the Bio-Bay influenced my decision to visit the island and I would suspect it influenced many others as well. The Vieques tourist industry weathered a temporary and not fully understood darkening of the bay in 2014. The experience may also have been better a few years ago when visitors were allowed to swim in the bay- the tour guides advised that authorities cracked down on the practice after a woman was bitten by a shark. Visitors must now stay aboard their kayak or pontoon boat. Various conditions affect viewing quality, most notably the moon. Responsible tour companies will not even run excursions during the time leading up to the full moon. Interestingly, the bay can be visited soon after a full moon because the moon rises later at night during this period. Island Adventures posted a calendar charting the best days to visit the bay in terms of moonlight, although at the time of this writing it hasn’t been updated past December 2014.
A visit to Mosquito Bay is often described as a “magical experience” as quoted on the Island Adventures Biobay Eco-tours website. The Abe’s Snorkeling and Bio-Bay Tours website says: “witness Vieques’ bioluminescent bay shine like an aqua-blue glowing cloud in this once-in-a-lifetime experience. The Bio Bay must be seen to believe! [sic]” We visited Mosquito Bay twice in successive days in March 2015 with good weather and no moonlight. Although the experience at times was impressive at times, our overall impression was one of disappointment that I believe resulted from disingenuous advertising by local tour companies. The companies, if they display photographs at all, display images with glowing blue water. Do a search on Google for “Bio Bay Puerto Rico” and similarly incredible photos appear. Even Pineterest has a page dedicated to incredible bioluminescent bay images, most supposedly from Puerto Rico.
The actual bay is considerably less bright. Forget any notion you might have of a bay glowing bright blue at night. The water only glows for a moment in response to agitation and it’s dim: a white t-shirt glowing under a blacklight is much brighter. A handful of disappointed visitors, after viewing what the bay is actually like, decry the photos they saw used in advertising as “Photoshop”. That’s not exactly fair in the sense that these professional photos are probably accomplished using long exposure times with fast lenses followed by illuminating the human subject with flash- not necessarily computer maniuplation. At the same time, it is a bit disingenuous to use them without disclaimer (which Island Adventures does in its gallery but not main page and which Abe’s doesn’t do at all). Exposures lasting seconds or even minutes in length can record images completely unlike those experienced by human eyes. Leave your camera at your hotel. Even with a few second exposure taken on the pontoon boat using a fairly fast F1.8 50mm lens, my photos captured no glow. I found a post from an amateur entitled BioBay Photos- Capturing the Glow who had a bit more success, but even after long exposures he still needed to enhance the results in Photoshop.
A Visit on the Island Adventures Electric Pontoon Boat
The first night we traveled on the bumpy road to Mosquito Bay on the Island Adventures school bus. According to our guesthouse, Island Adventures has the strongest scientific credentials of the various tour companies on Vieques with naturalists on staff. Unlike our Abe’s guide the following night, the Island Adventures guide went into detail about Pyrodinium bahamense, the dinoflagellate responsible for the Bio-Bay phenomenon. The microorganism is found elsewhere in the Atlantic Ocean, but Mosquito Bay appears to have particularly favorable conditions for it to thrive. Among these factors are said to be salinity, water temperature, the surrounding mangroves, and the narrow mouth of the Bay.
The Island Adventures electric pontoon boat is a quiet and more environmentally friendly alternative to diesel or gasoline powered boats plying the bioluminescent bays elsewhere in Puerto Rico. It is a stable platform more suitable than kayaks for the less physically abled, ambitious photographers, and those anxious about paddling in very low light conditions. The scientific detail of the Island Adventures talk was very high, at least at the beginning, discussing in detail the dinoflagellates and mangroves. The boat is not as satisfying a way of seeing the bioluminescence, unfortunately. The effect is dim and brief and only occurs in response to agitation of the water. In a kayak, visitors have access to the water directly and can cause the agitation by paddling or splashing. On the pontoon boat, the access is a lot less. There’s the wake (which Rachel said looked less like glowing than “sea foam”) and brief zig-zag glows of fish startled by the boat or the crew’s stomping, but that’s it. The crew brings a bucket of water on board so you can splash to create the effect, and you can descend the ladder on the boat enough to splash your legs briefly, but overall the experience is quite disappointing. The only really impressive moment was when they threw the bucket of water back!
The second half of the Island Adventures tour doesn’t even bother with the Bio-Bay: the guide just points out constellations with a powerful laser. Unlike the strong scientific discussion up to that point, this talk was strictly about the mythology behind the constellations. It is true that the Bio-Bay is very dark and suitable for stargazing. Even with some light pollution from residential lights on the hillside north of the bay, the only other places I’ve seen such bright stars were Crater Lake National Park and in western Canada. Still, the tour is advertised as a Bio-Bay, not stargazing excursion.
Mosquito Bay by Kayak
The next night we joined one of Abe’s Bio-Bay tours as part as a longer half day excursion. There were at least fifteen two-person kayaks of visitors who were launched from the shore and told to follow the blinking light attached to the guide. It was a bit of a circus, with novice kayakers weaving back and forth, cutting off and crashing into other kayaks. We were amused to pass a kayak with a couple of Chinese women chanting “left, left, left” in Mandarin. We gathered out in the bay where our guide gave a brief talk, a far less detailed one than on the Island Adventures tour. After two more relocations, our guide released us to explore within a defined area. I noticed there were kayaks on the periphery of the area with no glowsticks, undoubtedly guides positioned to make sure nobody wandered off. At any rate, it was nice to get away from the novices
Either the night was getting even darker, or the area was particularly favorable for bioluminescence, because the glow did get a little brighter. As greater agitation causes greater light, we found that we could get a strong effect by increasing our speed. We amused ourselves by paddling at flank speed. Move fast enough and you begin to get a glowing bow wave, wake, and even glowing eddies following the paddle splashes. Other kayakers laughed as we zoomed by them like a glowing torpedo. I’m even prepared to say the experience was magical. I simply disagree with the tour companies’ misleading advertising, though judging by rave reviews on sites like TripAdvisor, it seems I’m one of the few who found the experience didn’t measure up to the hype. The Bio-Bay is fascinating for what it is and I hope that its reputation leads to continuing development of the local economy.
Selection of Licensed Tour Operators
- Abe’s, $45 cash/$50 credit card, kayak, Esperanza
- Black Beard Sports, $65, kayak, Isabel II (reportedly offers several free pickup locations)
- Island Adventures, $50, electric pontoon boat, Esperanza
Series about Puerto Rico
- Planning a Trip to Puerto Rico
- Old San Juan, Puerto Rico
- El Yunque National Forest, Puerto Rico
- Dinner in Loíza
- The Flight to Vieques Island, Puerto Rico
- Isla de Vieques
- The Bioluminescent Bay on Vieques
- Snorkeling, Skeeters, and Paso Finos on Vieques