What Fish You Will See Snorkeling San Juan
San Juan reef sits on the northern edge of the Caribbean, where Atlantic and Caribbean species mix. On a single snorkel session at Escambron or off a catamaran to Icacos cays you can encounter 30 to 50 different fish species, plus rays, turtles and the odd nurse shark sleeping under a ledge.
This guide names the most common species you will see, the rare ones to look for and the ones you should never touch.
Reef fish you will see every time
Sergeant majors (blue and yellow striped, palm sized), blue tangs, yellowtail snapper, parrotfish in three colors (stoplight, queen, princess), French angelfish and grunts. These five are present on every San Juan reef, year round, and account for around half of the fish you photograph.
Sergeant majors will swim right up to your mask and follow you for the whole session. Parrotfish are the ones biting the coral with the loud crunching sound, that is healthy reef maintenance.
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Larger fish to look for
Tarpon (silver, up to 1.5 meters, common in Condado Lagoon at dawn), barracuda (motionless under the surface, stay still and they will move on), green moray eels (in holes, do not put your hand near), nurse sharks (under ledges, harmless if not disturbed) and southern stingrays (sandy bottoms, easy to spot but keep your distance).
None of these are aggressive to snorkelers in San Juan. Almost all bites that happen are from people putting hands inside crevices or grabbing rays. Keep both hands at your sides while floating.
Sea turtles and rays
Green sea turtles are resident in Escambron beach. You will usually see one or two per snorkel session, grazing seagrass between coral heads. Hawksbill turtles are rarer and prefer reef edges. Federal law requires you to stay 10 feet away, never touch and never chase.
Spotted eagle rays cruise the reef in pairs. Southern stingrays rest on the sand. Both are easy to photograph from above without harassment. The yellow stingray, smaller and harder to see, hides in sand under shallow water at Escambron.
Fish you should NOT touch
Fire coral (mustard yellow, often mistaken for coral, painful burn for hours), lionfish (invasive, beautiful, venomous spines), sea urchins (black spiked balls in cracks, the spines break off in skin), Portuguese man o war (blue translucent floats on stormy days, dangerous tentacles).
If you see a lionfish, take a photo and tell your guide. Puerto Rico runs lionfish removal programs because they are destroying reef ecosystems.
Best time of day to see fish
Sunrise (6 to 8 AM) has the most fish activity and the calmest water. Sunset (5 to 6 PM) is second best. Midday (11 AM to 2 PM) the fish are deep in the coral and visibility drops because of glare.
Tuesday to Thursday at Escambron is significantly less crowded than weekends. Local snorkelers know this.
On any San Juan snorkel you will meet 30 plus species in two hours. Bring an underwater camera. Stay 10 feet from turtles. Never touch the reef or the fish. The marine reserve protects everything, and you are a guest.
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