Fajardo bio bay (Laguna Grande): 4 Tour Operators Compared

Quick picks

Lowest price Yokahú Kayak Trips $55 per person for Bio Bay Kayaking
Youngest passengers Eco Adventures 5+

Bio bay nights, next 30 days

The glow is easiest to see when the moon is down during tour hours, roughly 7:30 to 10 pm. The next run of dark evenings is Oct 30 to Nov 12. Estimated from the moon's phase and typical rise times, so treat it as a guide and check the forecast for clouds.

Fri Oct 23Bright, 95% of the moon lit
Sat Oct 24Bright, 99% of the moon lit
Sun Oct 25Bright, 100% of the moon lit
Mon Oct 26Bright, 99% of the moon lit
Tue Oct 27Bright, 96% of the moon lit
Wed Oct 28Bright, 91% of the moon lit
Thu Oct 29Some moon, 84% of the moon lit
Fri Oct 30Dark, 76% of the moon lit
Sat Oct 31Dark, 66% of the moon lit
Sun Nov 1Dark, 56% of the moon lit
Mon Nov 2Dark, 45% of the moon lit
Tue Nov 3Dark, 35% of the moon lit
Wed Nov 4Dark, 25% of the moon lit
Thu Nov 5Dark, 16% of the moon lit
Fri Nov 6Dark, 9% of the moon lit
Sat Nov 7Dark, 4% of the moon lit
Sun Nov 8Dark, 1% of the moon lit
Mon Nov 9Dark, 0% of the moon lit
Tue Nov 10Dark, 1% of the moon lit
Wed Nov 11Dark, 5% of the moon lit
Thu Nov 12Dark, 10% of the moon lit
Fri Nov 13Some moon, 18% of the moon lit
Sat Nov 14Some moon, 27% of the moon lit
Sun Nov 15Some moon, 36% of the moon lit
Mon Nov 16Bright, 47% of the moon lit
Tue Nov 17Bright, 57% of the moon lit
Wed Nov 18Bright, 68% of the moon lit
Thu Nov 19Bright, 77% of the moon lit
Fri Nov 20Bright, 85% of the moon lit
Sat Nov 21Bright, 92% of the moon lit

Dark: moon down or nearly new Some moonlight Bright moon

Every option side by side

Operator	What you get	From	Length	Group	Min age	Cancellation	Book
Yokahú Kayak Trips	Bio Bay KayakingIncludes Kayak equipment, Safety briefing, Ecosystem explanation, Snacks and refreshments, Photos posted on Facebook	$55 per person	2 hours		6+		Check dates
Eco Adventures	Night Kayaking and Bioluminescent Bay TourIncludes Kayaking and safety instruction, Bilingual naturalist guide	$63 per person	Approximately 1.5 to 2 hours		5+		Check dates
Island Kayaking Adventure	Bioluminescent Night Kayaking AdventureIncludes Kayak, Life jacket, Eco-interpretive guide with CPR/first aid, Safety instruction	$65 per person	1.5 hours	Minimum 6 guests	6+		Check dates
Kayaking Puerto Rico	Fajardo Bio Bay Kayak TourIncludes Kayak and paddles, Life jacket, Night navigation lights, Safety instruction, Bug repellent, Snacks and water, Eco-interpretive guide	$70 per person	2 hours including 15 minutes of instruction	Minimum 6 guests or tour is rescheduled/cancelled without penalty	6+ (ages 6-13 share a kayak with an adult)	Full refund if cancelled 48+ hours before check-in; operator decides weather cancellations and offers reschedule or refund.	Check dates
Yokahú Kayak Trips	Bio Bay & El Yunque Rainforest Tour	$115 per person	8.5 hours		6+		Check dates
Eco Adventures	Luquillo Beach, Yunque Rainforest, Bio Bay ComboIncludes Bus transportation	$165 per person	10 hours		5+		Check dates

From each operator's own website, checked October 22, 2026. How we compare.

Kayak Village and PR-987 in Las Croabas

Las Croabas, on PR-987 in Fajardo, is the launch area for Laguna Grande. Kayaking Puerto Rico checks guests in at its Kayak Village, PR-987 Km 5, and asks them to arrive 20 minutes early to park before the 15-minute check-in. Eco Adventures meets on the same road in Las Croabas and has free parking. Island Kayaking Adventure lists an address on Carretera Cabezas de San Juan, and Yokahú Kayak Trips gives only a Fajardo postal code.

Kayaks enter the lagoon through a red mangrove channel inside Las Cabezas de San Juan Nature Reserve, according to Kayaking Puerto Rico. Discover Puerto Rico, the island's tourism board, points out that Laguna Grande is technically a lagoon joined to the sea by that narrow channel. Being closest to San Juan makes it the most visited of the island's bio bays, the board says. It estimates the drive at about 1 hour 15 minutes, against Kayaking Puerto Rico's one hour from the metro area.

Las Croabas and the Fajardo coast from above — Photo: Stan Shebs, CC BY-SA 3.0

Pyrodinium bahamense and the August to November peak

Pyrodinium bahamense, a dinoflagellate, is the dominant glowing species in Laguna Grande, according to a 2024 study by Yogani Govender and Mark Jury in Revista de Biología Tropical. Dinoflagellates glow when disturbed, Discover Puerto Rico explains. Kayaking Puerto Rico says sparkles appear with each paddle stroke, and Island Kayaking Adventure says some nights are brighter and others subtle. The tourism board warns that photos rarely capture the glow well.

The study sampled three sites in the lagoon from 2016 to 2021. Densities were low in 2016 and 2017. From 2018 to 2021 the dinoflagellates bloomed often and strongly, and the authors use hurricanes to mark the change, saying storms "rake and refresh" the lagoon. Seasonally, numbers ran low in late winter and higher from August to November. Light winds, high tides and low salinity during seasonal warming appeared to sustain reproduction.

Less moonlight means a brighter glow, according to Kayaking Puerto Rico, and both it and Eco Adventures say brightness cannot be guaranteed. Discover Puerto Rico recommends new-moon nights and says to avoid the full moon. Yokahú Kayak Trips says it has ways to make a moonlit night darker. Eco Adventures lists rainfall alongside moonlight as a factor in visibility. Swell matters as well: in November 2013 scientists linked a drop in the lagoon's glow to a long, heavy swell, El Nuevo Día reported.

Swimming ban, weight limits and seasonal sargassum

Swimming is not permitted in Laguna Grande; Discover Puerto Rico says the ban protects the dinoflagellates, and Kayaking Puerto Rico also prohibits diving. The tourism board's Spanish guide says motorboats should stay out of protected zones, and all four operators here use kayaks. Leave flashlights off and phone screens dark on the water, the board asks. Its English page suggests a cream or balm repellent put on half an hour or more before the tour, while the Spanish guide says to wear no repellent or sunscreen.

Kayaking Puerto Rico takes paddlers from age 6; ages 6 to 13 share a kayak with an adult, and ages 14 to 17 need an adult on the tour. Its limits are 240 lbs per person and 425 lbs per kayak. Eco Adventures starts at age 5 and allows up to 250 lbs per person. Yokahú Kayak Trips does not take pregnant guests, and Kayaking Puerto Rico calls the tour unsuitable for pregnancy, heart conditions, epilepsy, recent surgery, or back, neck, arm or leg problems.

Wind and current can make paddling harder, though the lagoon has no open-water waves, Kayaking Puerto Rico says. It warns that sargassum can drift in at some times of year, and Eco Adventures says the mangroves may smell of sulfur. Wear shoes and clothing you don't mind soaking (flip-flops are fine) and pack a towel and dry clothes. Kayaking Puerto Rico hands out bug repellent and asks for waterproof cameras, preferably on a leash.

Yokahú at $55, Kayaking Puerto Rico at $70

Yokahú Kayak Trips is the lowest at $55 for 2 hours. It says its guides are certified by the American Canoeing Association, posts tour photos on Facebook, and offers private tours and group rates by phone. Eco Adventures charges $63 for 1.5 to 2 hours with bilingual naturalist guides. It uses tandem kayaks only and may pair odd-numbered parties with other guests. Its kayak tour leaves transport to you, but its 10-hour Luquillo Beach, El Yunque and bio bay combo ($165) includes a bus.

Island Kayaking Adventure lists its 1.5-hour tour from $65, though its page description says from $60. It needs at least 6 guests and says its guides hold CPR and first aid certification. Kayaking Puerto Rico costs the most, $70 for 2 hours including 15 minutes of instruction, with check-ins at 5:45 pm and 8 pm from October to January, Monday to Saturday. Below 6 guests it calls ahead to reschedule or cancel without penalty, and it lists three local drivers for rides.

Before you book

Book a round-trip taxi before you go. Kayaking Puerto Rico says rides cannot be arranged on the spot after the tour and lists three local drivers on its tour page.
Pick a night near the new moon, when Discover Puerto Rico says the glow is most intense, and avoid the full moon.
Leave valuables behind. Kayaking Puerto Rico says to bring nothing that cannot get wet, and cameras must be waterproof.
Getting there. Discover Puerto Rico puts the drive from San Juan at about 1 hour 15 minutes on PR-3. Tours run at night in several time slots, and the board suggests staying overnight in Fajardo.

The operators

Yokahú Kayak Trips

from $55 per person

Bio Bay Kayaking and 1 more option

Length: 2 hours
Age: 6+

Guides certified by the American Canoeing Association

Check dates All details

Eco Adventures

from $63 per person

Night Kayaking and Bioluminescent Bay Tour and 1 more option

Length: Approximately 1.5 to 2 hours
Age: 5+
Weight: 250 lbs per person, 425 lbs combined per double kayak

Tandem kayaks; odd-numbered parties may be paired

Check dates All details

Island Kayaking Adventure

from $65 per person

Bioluminescent Night Kayaking Adventure

Length: 1.5 hours
Group: Minimum 6 guests
Age: 6+

Business address on Carr. Cabezas de San Juan, Fajardo

Check dates All details

Kayaking Puerto Rico

from $70 per person

Fajardo Bio Bay Kayak Tour

Length: 2 hours including 15 minutes of instruction
Group: Minimum 6 guests or tour is rescheduled/cancelled without penalty
Age: 6+ (ages 6-13 share a kayak with an adult)
Weight: 240 lbs per person, 425 lbs combined per kayak

Two departures nightly Monday to Saturday; start times shift by season (e.g. 5:45 and 8:00 PM Oct-Jan)

Check dates All details

Head to head

Sources

Prices and policies come from each operator's own pages, read on October 22, 2026. Seasons, rules and local details come from the pages below.