Alligator Reef
Located in the Upper Keys, the Alligator Reef Sanctuary Preservation Area (SPA) is a dive site that spans from NW to SE of Cheeca Rocks. It acts as a bridge between the shallow reefs of the Upper Keys and the deeper reefs of the Middle Keys. This rectangular SPA consists of a small bank reef that offers protection to a beautiful spur-and-groove system, a vibrant reef crest, and a portion of the stunning northeast rubble ridge.
Divers who explore this site will be delighted to encounter a diverse array of marine life. With 186 identified marine fish species, including moray eels, lobsters, groupers, nurse sharks, and turtles, there is always something fascinating to discover beneath the waves. Furthermore, this site is also home to a coral outplanting site, showcasing the importance of conservation efforts for the underwater ecosystem.
Considered a must-see on any dive trip, Alligator Reef SPA is renowned for its abundant fish population. It boasts more fish species than any other dive site in the Keys, with a current count of 189 identified species. A typical dive day at Alligator Reef SPA offers encounters with moray eels, spiny and slipper lobsters, an impressive number of groupers, nurse sharks, and often, various turtle species. As a bonus, divers will have the opportunity to witness the coral outplanting and monitoring project by I.CARE, a conservation initiative supported in part by Key Dives.
With maximum depths reaching 9 meters and visibility extending up to 13 meters, this dive site is suitable for divers of all levels, including beginners, advanced divers, and experts. Snorkelers can also enjoy the beauty of Alligator Reef SPA, making it an accessible underwater paradise for enthusiasts of all types.
For those looking to explore more sites in the area, the USS Alligator Shipwreck is a close location that offers a unique diving experience. Immerse yourself in the underwater wonders of the Alligator Reef SPA and discover the breathtaking diversity of marine life in this captivating dive destination.
Divers who explore this site will be delighted to encounter a diverse array of marine life. With 186 identified marine fish species, including moray eels, lobsters, groupers, nurse sharks, and turtles, there is always something fascinating to discover beneath the waves. Furthermore, this site is also home to a coral outplanting site, showcasing the importance of conservation efforts for the underwater ecosystem.
Considered a must-see on any dive trip, Alligator Reef SPA is renowned for its abundant fish population. It boasts more fish species than any other dive site in the Keys, with a current count of 189 identified species. A typical dive day at Alligator Reef SPA offers encounters with moray eels, spiny and slipper lobsters, an impressive number of groupers, nurse sharks, and often, various turtle species. As a bonus, divers will have the opportunity to witness the coral outplanting and monitoring project by I.CARE, a conservation initiative supported in part by Key Dives.
With maximum depths reaching 9 meters and visibility extending up to 13 meters, this dive site is suitable for divers of all levels, including beginners, advanced divers, and experts. Snorkelers can also enjoy the beauty of Alligator Reef SPA, making it an accessible underwater paradise for enthusiasts of all types.
For those looking to explore more sites in the area, the USS Alligator Shipwreck is a close location that offers a unique diving experience. Immerse yourself in the underwater wonders of the Alligator Reef SPA and discover the breathtaking diversity of marine life in this captivating dive destination.
Diving Conditions Score for Alligator Reef
7.4
GoodGood diving conditions!
The score is based on a calculation of the current weather and sea conditions.
Dive Site Overview for Alligator Reef
Depth
9m
Visibility
13m
Experience Level
beginner
advanced
expert
Weather Conditions for Alligator Reef
Wave Height
0.68m
Wind Speed
22.3 m/s
Water Temp
30.3°C
Visibility
25.3km
Cloud Cover
1%
Wave Period
4.1s
Air Temperature
29.8°C
Precipitation
0 mm
Detailed 7-Day Diving Forecast for Alligator Reef
Alpha
Dive Score Chart for Alligator Reef
Best time to dive: 17:00 with score 7.957352380952382/10. Water conditions: Waves 0.6m, Wind 14.2 m/s.Best night dive time: 21:00 with score 7.456206425702812/10.
Chart showing hourly dive conditions including wave height, wind speed, water temperature, and visibility throughout the day.
Sunrise at Alligator Reef: 06:00
Sunset at Alligator Reef: 18:00
Optimal diving conditions at Alligator Reef are affected by daylight hours. Sunrise occurs at 06:00 and sunset at 18:00, which impacts visibility and water temperature for scuba diving and snorkeling.
Best Overall
17:00Score: 8.0/10
Waves: 0.6m (4.2s), Wind: 14.2 m/s
Best Night
21:00Score: 7.5/10
Waves: 0.58m, Wind: 19 m/s
Seasonal Analysis for Alligator ReefAlpha
Historical patterns and best seasons for diving at Alligator Reef
The dive score combines all factors to rate overall diving conditions throughout the year. Higher scores indicate better diving conditions.
Monthly Dive Score Analysis - Seasonal Diving Conditions
Higher values indicate better diving conditions
Seasonal DiveScore Chart
This chart displays monthly diveScore data throughout the year, showing seasonal patterns. The data is presented as a bar chart with an overlaid line graph.Dive scores range from 1 to 10, with 10 being optimal conditions.
Higher values indicate better diving conditions
Best Season for Alligator Reef
Winter
Avg. Score: 8.8/10
Winter offers the best overall diving conditions with calmer seas and better visibility, despite cooler temperatures.
Best Months for Alligator Reef
February
Score: 8.8
December
Score: 8.8
January
Score: 8.7
Ideal Conditions for Alligator Reef
Water Temp
26.5°C / 79.7°F
September
Visibility
11.5m / 37.7ft
November
Wave Height
2.2m / 7.2ft
November
Wave Period
8.0s
January
Seasonal Insights for Alligator Reef
Alligator Reef shows typical northern hemisphere patterns with July being the warmest month (28.3°C) and January the coldest (17.8°C). The calmest conditions typically occur in November with average wave heights of 2.2m and wave periods of 8.0s. The most comfortable wave conditions are in November with a low wave steepness ratio, creating gentler swells. January offers the longest wave periods (8.0s), creating more comfortable and predictable conditions for boat entries and exits. Ocean currents are slowest in January (0.5m/s) and strongest in January (0.5m/s). February is usually the driest month with 0.0mm of precipitation. For beginners, the best time to visit would be during November to January, when ocean conditions are calmer with long-period waves and currents are typically weaker. Experienced divers might enjoy the challenges and potentially better visibility during the shoulder seasons, with moderate currents that can improve marine life encounters.
Last updated: 1 min. ago - Jun 29, 2026
Note: This dive site is not a verified dive site. Please dive with caution. This dive site might have incorrect information by the community.
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